This document provides an overview of the major joints in the lower extremity, including the hip, knee, ankle, and foot. It describes the tissues, motions, biomechanics, configurations, ligaments, and common pathologies of each joint. The document is authored by Kylie Bauman, Jessie Brown, Sivan Fogel, Mariah Granzella, Michael Kaspin, Kelsey Poos-Benson, Megan Smith, and Allie Stone as part of an arthrology guide for the lower extremity.
This document provides a review of the use of mesenchymal stem cells for the treatment of canine osteoarthritis. It begins with an overview of canine osteoarthritis, including its prevalence, pathophysiology, and current treatment options. Current treatments discussed include NSAIDs, steroidal drugs, and nutraceuticals. The document then reviews the potential of mesenchymal stem cells as a novel treatment for canine osteoarthritis, discussing both autologous and heterologous sources of adipose-derived mesenchymal stem cells. Several studies are summarized that show stem cell therapy can improve signs of osteoarthritis in dogs without significant side effects by aiding cartilage repair and modulating the immune system. The review concludes
Ficha de preparação para o teste de ciências naturaisHelena Ferreira
This document contains a preparation guide for a natural science test with questions about the digestive system. It includes questions about the functions of the digestive system, definitions of digestion and related terms, the components of the digestive tract and associated glands, descriptions of movements in the digestive system, the journey of food through the esophagus and stomach, digestive juices and their roles, and absorption and assimilation of nutrients. Diagrams are included relating to the questions.
The document provides information on various body systems including:
- The cardiovascular system including parts and effects of exercise, drugs, diet and rest
- The respiratory system including parts and effects of exercise, drugs and diet
- The muscular system including muscles, effects of exercise, drugs, rest and diet, and injuries
- The skeletal system including bones, functions, effects of exercise, drugs, rest and diet, injuries, and joints
It also discusses topics like nutrition, weight management, performance enhancing substances, and injury risks.
This document provides an introduction to arthrology, the study of joints. It defines arthrology and discusses the classification and basic structures of joints. Joints are classified based on both their function and structure. Based on structure, joints are categorized as fibrous, cartilaginous, or synovial. Synovial joints are the most common and complex type, allowing for free movement. The document outlines the key components of synovial joints and provides examples of different joint types, including ball and socket, hinge, pivot, saddle, condyloid, and gliding joints.
The document defines joints and their classifications. It discusses the three main classifications of joints: fibrous joints which are immovable, cartilaginous joints which are slightly movable, and synovial joints which are freely movable. It provides examples of different types of synovial joints classified by shape and mobility, including hinge, pivot, ball and socket, and gliding joints.
Cartilage is a flexible connective tissue found in joints between bones. There are three main types of cartilage - hyaline, fibrocartilage, and elastic cartilage. Cartilage provides support, acts as a gliding surface in joints, and serves as a template for bone formation. Joints, also called articulations, are places where bones connect. The three major types of joints are fibrous, cartilaginous, and synovial joints. Synovial joints are the most common and include structures like bones, cartilage, synovial fluid, ligaments, and a joint capsule. There are different types of synovial joints based on their shape and movement capabilities, including hinge, ball-and-socket
The document discusses the classification and types of joints in the human body. It describes three main types of joints - fibrous joints which lack synovial cavities and permit little movement, cartilaginous joints which also lack synovial cavities, and synovial joints which have synovial cavities and are freely movable. It provides examples and characteristics of each joint type and discusses factors that affect their range of motion.
There are 206 bones in the human body that serve several functions including support, protection, mineral storage, movement, and blood cell formation. Bones are made of connective tissue and composed of protoplasm, collagen, blood vessels, and marrow. There are several shapes of bones including long, flat, irregular, and short. Joints are where parts of the skeleton meet and allow varying amounts of mobility. Joints are classified based on their structure and function and can be diarthrosis, amphiarthrosis, or synarthrosis depending on freedom of movement. Synovial joints contain articular cartilage, synovial fluid, articular capsules, ligaments, nerves and blood vessels.
This document provides a review of the use of mesenchymal stem cells for the treatment of canine osteoarthritis. It begins with an overview of canine osteoarthritis, including its prevalence, pathophysiology, and current treatment options. Current treatments discussed include NSAIDs, steroidal drugs, and nutraceuticals. The document then reviews the potential of mesenchymal stem cells as a novel treatment for canine osteoarthritis, discussing both autologous and heterologous sources of adipose-derived mesenchymal stem cells. Several studies are summarized that show stem cell therapy can improve signs of osteoarthritis in dogs without significant side effects by aiding cartilage repair and modulating the immune system. The review concludes
Ficha de preparação para o teste de ciências naturaisHelena Ferreira
This document contains a preparation guide for a natural science test with questions about the digestive system. It includes questions about the functions of the digestive system, definitions of digestion and related terms, the components of the digestive tract and associated glands, descriptions of movements in the digestive system, the journey of food through the esophagus and stomach, digestive juices and their roles, and absorption and assimilation of nutrients. Diagrams are included relating to the questions.
The document provides information on various body systems including:
- The cardiovascular system including parts and effects of exercise, drugs, diet and rest
- The respiratory system including parts and effects of exercise, drugs and diet
- The muscular system including muscles, effects of exercise, drugs, rest and diet, and injuries
- The skeletal system including bones, functions, effects of exercise, drugs, rest and diet, injuries, and joints
It also discusses topics like nutrition, weight management, performance enhancing substances, and injury risks.
This document provides an introduction to arthrology, the study of joints. It defines arthrology and discusses the classification and basic structures of joints. Joints are classified based on both their function and structure. Based on structure, joints are categorized as fibrous, cartilaginous, or synovial. Synovial joints are the most common and complex type, allowing for free movement. The document outlines the key components of synovial joints and provides examples of different joint types, including ball and socket, hinge, pivot, saddle, condyloid, and gliding joints.
The document defines joints and their classifications. It discusses the three main classifications of joints: fibrous joints which are immovable, cartilaginous joints which are slightly movable, and synovial joints which are freely movable. It provides examples of different types of synovial joints classified by shape and mobility, including hinge, pivot, ball and socket, and gliding joints.
Cartilage is a flexible connective tissue found in joints between bones. There are three main types of cartilage - hyaline, fibrocartilage, and elastic cartilage. Cartilage provides support, acts as a gliding surface in joints, and serves as a template for bone formation. Joints, also called articulations, are places where bones connect. The three major types of joints are fibrous, cartilaginous, and synovial joints. Synovial joints are the most common and include structures like bones, cartilage, synovial fluid, ligaments, and a joint capsule. There are different types of synovial joints based on their shape and movement capabilities, including hinge, ball-and-socket
The document discusses the classification and types of joints in the human body. It describes three main types of joints - fibrous joints which lack synovial cavities and permit little movement, cartilaginous joints which also lack synovial cavities, and synovial joints which have synovial cavities and are freely movable. It provides examples and characteristics of each joint type and discusses factors that affect their range of motion.
There are 206 bones in the human body that serve several functions including support, protection, mineral storage, movement, and blood cell formation. Bones are made of connective tissue and composed of protoplasm, collagen, blood vessels, and marrow. There are several shapes of bones including long, flat, irregular, and short. Joints are where parts of the skeleton meet and allow varying amounts of mobility. Joints are classified based on their structure and function and can be diarthrosis, amphiarthrosis, or synarthrosis depending on freedom of movement. Synovial joints contain articular cartilage, synovial fluid, articular capsules, ligaments, nerves and blood vessels.
The document discusses a scientific article comparing the diets, behaviors, and physical traits of spider and howler monkeys. It aims to show that obtaining food was a major factor in primate evolution. Students are asked questions about the differences between the two monkeys, which type humans resemble most, what drove increased brain size in early humans, how a study of chimpanzee digestion supported the idea that early humans ate more fiber, and two strategies monkeys use to cope with nutritional challenges and related adaptations.
This document provides information about cell structures and their functions. It defines key terms like organelles, plasma membrane, cytoplasm, nucleus, ribosomes, endoplasmic reticulum, Golgi bodies, lysosomes, mitochondria, chloroplasts, and vacuoles. For each structure, it describes their shape, components, and main roles within the cell. The document also compares and contrasts the processes of photosynthesis within chloroplasts and respiration within mitochondria.
The document provides an overview of the major structures and processes of the digestive system, including the mouth, esophagus, stomach, small intestine, large intestine, liver, gallbladder and pancreas. It describes the 6 basic processes of digestion and the 4 layers of the GI tract. Key details are provided on teeth, saliva, gastric juices, enzymes, peristalsis, absorption of nutrients, and the roles of the pancreas, liver and bile in digestion. The stages of digestion and absorption in the small and large intestines are summarized.
The document is a biology worksheet that provides definitions and questions about key concepts. It introduces 7 vocabulary words - biosphere, ecosystem, organism, cell, DNA, gene - and asks students to write their definitions and a fact for each. The worksheet then continues with multiple choice and short answer questions about these terms and how they relate to the domains and kingdoms of life.
Human body structure and function worksheetclonardo
This document discusses the structure and function of living organisms from the cellular level up. It explains that cells form tissues, tissues form organs, organs form organ systems, and organ systems work together to maintain homeostasis in the body. The document asks questions about how the structure of tissues like epithelial, connective, and muscle tissue contribute to their functions. It also asks how the structure of organs like the heart, stomach, lungs, and others contribute to their functions. Finally, it lists the 11 organ systems in the human body and instructs students to fill in which organs are part of each system.
Pedagogy has been validated as a science based on the essential elements needed for this criterion, which focus on its system of laws, categories, methods and principles; its social and political connection; and its view of man as the center and end of its epistemological and practical development. Pedagogy constitutes theoretical reflection that is not limited to the practical transmission of knowledge nor does it stop at the important reality of the curriculum and contents, or the competencies related to the educational fact. Pedagogy is located in the space-time of society, in its values and principles, and dares to propose how education should be carried out, under what conditions and why.
This document contains 13 short-answer questions for a sports studies examination covering topics like:
- The importance of warming up before exercise and the stages and physiological responses in a warmup.
- Types of stretches and their sporting benefits.
- The lactic acid energy system and an example of its use in a team game.
- Processes of the Krebs cycle and electron transport chain in aerobic energy production.
- Main functions of carbohydrates, fats, and proteins in an athlete's diet.
- How the body accesses and uses carbohydrate stores for endurance performance.
- Advantages and disadvantages of creatine loading for athletes.
- Phys
Helper T cells recognize antigens displayed on macrophages and activate other immune cells including B cells and T cells. Activated B cells produce antibodies that destroy pathogens, while activated T cells destroy pathogen-infected cells. Memory cells remain after an infection to provide faster protection if the same pathogen is encountered again. Vaccines provide active artificial immunity by exposing the immune system to an inactivated or weakened form of a pathogen. They work by generating memory cells and antibodies that can quickly respond to a real infection.
The discovery of the microscope led to the discovery of cells and the cell theory. Observations showed that all living things are made of one or more cells, which are the basic units of structure and function in living things. Cells are capable of carrying out basic functions of life and new cells are produced from existing cells. Eukaryotic cells have organelles and a nucleus enclosed within membranes, while prokaryotic cells like bacteria lack internal membranes and organelles. Organelles like the nucleus, mitochondria and chloroplasts have specialized functions in animal and plant cells.
This document summarizes evidence from research on various complementary and integrative therapies including massage, aromatherapy, touch therapies like Reiki, and music therapy. It discusses challenges in researching individualized and natural treatments, and presents results from studies showing benefits like reduced pain, anxiety and nausea from therapies like massage, aromatherapy, and music. It also outlines programs that have successfully implemented complementary approaches in hospital settings, improving patient outcomes and reducing costs.
The document provides information about the human nervous system and its regulation of homeostasis. It discusses the similarities and differences between the nervous system and endocrine system. The nervous system uses electrical signals transmitted along neurons, while the endocrine system uses chemical messengers. Both play major roles in homeostasis.
The nervous system has three types of neurons - sensory neurons which receive stimuli near sensory organs, interneurons which transmit signals between sensory and motor neurons, and motor neurons which activate effectors like muscles. Nerves are bundles of neurons that can be motor, sensory, or mixed. Individual neurons have dendrites, an axon, and a cell body. Signals move in one direction via depolarization along the axon.
The
The document is about human locomotion and the body systems that enable it. It discusses the skeletal system, which contains bones that provide structure, anchor muscle action, protect organs, and allow for movement. Cartilage cushions joints and is flexible. The muscular system includes skeletal muscles that appear striated and are used to move bones. Tendons connect muscles to bones, while ligaments connect bones to other bones at joints. Problems that can affect the skeletal system include arthritis, which causes inflammation and pain in joints and usually occurs in older individuals, and tendonitis, which is inflammation of tendons commonly seen in athletes.
This workbook covers three lessons on the major human body systems, including the skeletal, circulatory, respiratory, muscular, digestive, nervous, and renal systems. Students are asked to label diagrams, define key terms, and describe the main functions of each system. The workbook contains information and exercises to help students learn about the structure and purpose of the main parts that make up the human body.
This document contains information about plant reproduction, including the structure and function of flower parts, pollination, fertilization, seed dispersal, and seed germination. It includes diagrams labeling flower parts, tables to fill out, descriptions of wind and insect pollination, and questions about the processes. The goal is for students to learn about how plants reproduce sexually through the production and interaction of male and female gametes within flowers.
This document contains a homework assignment on genetic material for a Living Environment class. It asks the student to define terms related to genetics like asexual reproduction, sexual reproduction, DNA, nucleotides, and double helix. It also asks the student to identify the poles of the DNA ladder model, nucleotide base pairing groups, fill in a diagram of DNA structure, define gene mutations, and answer whether the environment can change an organism's phenotype.
This document contains a homework assignment on genetic material for a Living Environment class. It asks the student to define terms related to genetics like asexual reproduction, sexual reproduction, DNA, nucleotides, and double helix. It also asks the student to identify the poles of the DNA ladder model, nucleotide base pairing groups, fill in a diagram of DNA structure, define gene mutations, and answer whether the environment can change an organism's phenotype.
This document provides an overview of herbs and supplements presented by Dr. Rachel Busse. It discusses the high rate of patient supplement use, potential risks including interactions and lack of regulation. Specific supplements are reviewed for their uses, dosages, and precautions when treating conditions like mood disorders, sleep, menopause, liver health, inflammation, arthritis, and more. Herbal teas and "kitchen medicines" made from common herbs are also outlined. Sources for additional information on supplements are recommended.
The document is a worksheet containing questions about the skeletal, respiratory, and circulatory systems of the human body. It asks students to identify parts of each system, describe their functions, and provide two facts learned about each from a video. The questions cover topics like the bones and joints that make up the skeletal system, the role of muscles in movement, how the lungs and heart work together in the respiratory system, and the components and circulation of blood in the closed transport system of the body. Students are asked to fill in blanks and label diagrams related to each bodily system.
This document contains slides from a presentation on stress reduction. It discusses how stress affects healthcare professionals and patients. It defines stress and identifies its causes such as overwork, role ambiguity, and understaffing. Long-term stress can increase risks of health issues like heart disease, diabetes and mental health problems. The presentation recommends organizational changes, stress management training, and coping strategies like mindfulness, social support and seeking help to reduce workplace stress.
The document discusses a scientific article comparing the diets, behaviors, and physical traits of spider and howler monkeys. It aims to show that obtaining food was a major factor in primate evolution. Students are asked questions about the differences between the two monkeys, which type humans resemble most, what drove increased brain size in early humans, how a study of chimpanzee digestion supported the idea that early humans ate more fiber, and two strategies monkeys use to cope with nutritional challenges and related adaptations.
This document provides information about cell structures and their functions. It defines key terms like organelles, plasma membrane, cytoplasm, nucleus, ribosomes, endoplasmic reticulum, Golgi bodies, lysosomes, mitochondria, chloroplasts, and vacuoles. For each structure, it describes their shape, components, and main roles within the cell. The document also compares and contrasts the processes of photosynthesis within chloroplasts and respiration within mitochondria.
The document provides an overview of the major structures and processes of the digestive system, including the mouth, esophagus, stomach, small intestine, large intestine, liver, gallbladder and pancreas. It describes the 6 basic processes of digestion and the 4 layers of the GI tract. Key details are provided on teeth, saliva, gastric juices, enzymes, peristalsis, absorption of nutrients, and the roles of the pancreas, liver and bile in digestion. The stages of digestion and absorption in the small and large intestines are summarized.
The document is a biology worksheet that provides definitions and questions about key concepts. It introduces 7 vocabulary words - biosphere, ecosystem, organism, cell, DNA, gene - and asks students to write their definitions and a fact for each. The worksheet then continues with multiple choice and short answer questions about these terms and how they relate to the domains and kingdoms of life.
Human body structure and function worksheetclonardo
This document discusses the structure and function of living organisms from the cellular level up. It explains that cells form tissues, tissues form organs, organs form organ systems, and organ systems work together to maintain homeostasis in the body. The document asks questions about how the structure of tissues like epithelial, connective, and muscle tissue contribute to their functions. It also asks how the structure of organs like the heart, stomach, lungs, and others contribute to their functions. Finally, it lists the 11 organ systems in the human body and instructs students to fill in which organs are part of each system.
Pedagogy has been validated as a science based on the essential elements needed for this criterion, which focus on its system of laws, categories, methods and principles; its social and political connection; and its view of man as the center and end of its epistemological and practical development. Pedagogy constitutes theoretical reflection that is not limited to the practical transmission of knowledge nor does it stop at the important reality of the curriculum and contents, or the competencies related to the educational fact. Pedagogy is located in the space-time of society, in its values and principles, and dares to propose how education should be carried out, under what conditions and why.
This document contains 13 short-answer questions for a sports studies examination covering topics like:
- The importance of warming up before exercise and the stages and physiological responses in a warmup.
- Types of stretches and their sporting benefits.
- The lactic acid energy system and an example of its use in a team game.
- Processes of the Krebs cycle and electron transport chain in aerobic energy production.
- Main functions of carbohydrates, fats, and proteins in an athlete's diet.
- How the body accesses and uses carbohydrate stores for endurance performance.
- Advantages and disadvantages of creatine loading for athletes.
- Phys
Helper T cells recognize antigens displayed on macrophages and activate other immune cells including B cells and T cells. Activated B cells produce antibodies that destroy pathogens, while activated T cells destroy pathogen-infected cells. Memory cells remain after an infection to provide faster protection if the same pathogen is encountered again. Vaccines provide active artificial immunity by exposing the immune system to an inactivated or weakened form of a pathogen. They work by generating memory cells and antibodies that can quickly respond to a real infection.
The discovery of the microscope led to the discovery of cells and the cell theory. Observations showed that all living things are made of one or more cells, which are the basic units of structure and function in living things. Cells are capable of carrying out basic functions of life and new cells are produced from existing cells. Eukaryotic cells have organelles and a nucleus enclosed within membranes, while prokaryotic cells like bacteria lack internal membranes and organelles. Organelles like the nucleus, mitochondria and chloroplasts have specialized functions in animal and plant cells.
This document summarizes evidence from research on various complementary and integrative therapies including massage, aromatherapy, touch therapies like Reiki, and music therapy. It discusses challenges in researching individualized and natural treatments, and presents results from studies showing benefits like reduced pain, anxiety and nausea from therapies like massage, aromatherapy, and music. It also outlines programs that have successfully implemented complementary approaches in hospital settings, improving patient outcomes and reducing costs.
The document provides information about the human nervous system and its regulation of homeostasis. It discusses the similarities and differences between the nervous system and endocrine system. The nervous system uses electrical signals transmitted along neurons, while the endocrine system uses chemical messengers. Both play major roles in homeostasis.
The nervous system has three types of neurons - sensory neurons which receive stimuli near sensory organs, interneurons which transmit signals between sensory and motor neurons, and motor neurons which activate effectors like muscles. Nerves are bundles of neurons that can be motor, sensory, or mixed. Individual neurons have dendrites, an axon, and a cell body. Signals move in one direction via depolarization along the axon.
The
The document is about human locomotion and the body systems that enable it. It discusses the skeletal system, which contains bones that provide structure, anchor muscle action, protect organs, and allow for movement. Cartilage cushions joints and is flexible. The muscular system includes skeletal muscles that appear striated and are used to move bones. Tendons connect muscles to bones, while ligaments connect bones to other bones at joints. Problems that can affect the skeletal system include arthritis, which causes inflammation and pain in joints and usually occurs in older individuals, and tendonitis, which is inflammation of tendons commonly seen in athletes.
This workbook covers three lessons on the major human body systems, including the skeletal, circulatory, respiratory, muscular, digestive, nervous, and renal systems. Students are asked to label diagrams, define key terms, and describe the main functions of each system. The workbook contains information and exercises to help students learn about the structure and purpose of the main parts that make up the human body.
This document contains information about plant reproduction, including the structure and function of flower parts, pollination, fertilization, seed dispersal, and seed germination. It includes diagrams labeling flower parts, tables to fill out, descriptions of wind and insect pollination, and questions about the processes. The goal is for students to learn about how plants reproduce sexually through the production and interaction of male and female gametes within flowers.
This document contains a homework assignment on genetic material for a Living Environment class. It asks the student to define terms related to genetics like asexual reproduction, sexual reproduction, DNA, nucleotides, and double helix. It also asks the student to identify the poles of the DNA ladder model, nucleotide base pairing groups, fill in a diagram of DNA structure, define gene mutations, and answer whether the environment can change an organism's phenotype.
This document contains a homework assignment on genetic material for a Living Environment class. It asks the student to define terms related to genetics like asexual reproduction, sexual reproduction, DNA, nucleotides, and double helix. It also asks the student to identify the poles of the DNA ladder model, nucleotide base pairing groups, fill in a diagram of DNA structure, define gene mutations, and answer whether the environment can change an organism's phenotype.
This document provides an overview of herbs and supplements presented by Dr. Rachel Busse. It discusses the high rate of patient supplement use, potential risks including interactions and lack of regulation. Specific supplements are reviewed for their uses, dosages, and precautions when treating conditions like mood disorders, sleep, menopause, liver health, inflammation, arthritis, and more. Herbal teas and "kitchen medicines" made from common herbs are also outlined. Sources for additional information on supplements are recommended.
The document is a worksheet containing questions about the skeletal, respiratory, and circulatory systems of the human body. It asks students to identify parts of each system, describe their functions, and provide two facts learned about each from a video. The questions cover topics like the bones and joints that make up the skeletal system, the role of muscles in movement, how the lungs and heart work together in the respiratory system, and the components and circulation of blood in the closed transport system of the body. Students are asked to fill in blanks and label diagrams related to each bodily system.
This document contains slides from a presentation on stress reduction. It discusses how stress affects healthcare professionals and patients. It defines stress and identifies its causes such as overwork, role ambiguity, and understaffing. Long-term stress can increase risks of health issues like heart disease, diabetes and mental health problems. The presentation recommends organizational changes, stress management training, and coping strategies like mindfulness, social support and seeking help to reduce workplace stress.
Similar to Final le arthrology guide table 25 (20)
PGx Analysis in VarSeq: A User’s PerspectiveGolden Helix
Since our release of the PGx capabilities in VarSeq, we’ve had a few months to gather some insights from various use cases. Some users approach PGx workflows by means of array genotyping or what seems to be a growing trend of adding the star allele calling to the existing NGS pipeline for whole genome data. Luckily, both approaches are supported with the VarSeq software platform. The genotyping method being used will also dictate what the scope of the tertiary analysis will be. For example, are your PGx reports a standalone pipeline or would your lab’s goal be to handle a dual-purpose workflow and report on PGx + Diagnostic findings.
The purpose of this webcast is to:
Discuss and demonstrate the approaches with array and NGS genotyping methods for star allele calling to prep for downstream analysis.
Following genotyping, explore alternative tertiary workflow concepts in VarSeq to handle PGx reporting.
Moreover, we will include insights users will need to consider when validating their PGx workflow for all possible star alleles and options you have for automating your PGx analysis for large number of samples. Please join us for a session dedicated to the application of star allele genotyping and subsequent PGx workflows in our VarSeq software.
TEST BANK For Brunner and Suddarth's Textbook of Medical-Surgical Nursing, 14...Donc Test
TEST BANK For Brunner and Suddarth's Textbook of Medical-Surgical Nursing, 14th Edition (Hinkle, 2017) Verified Chapter's 1 - 73 Complete.pdf
TEST BANK For Brunner and Suddarth's Textbook of Medical-Surgical Nursing, 14th Edition (Hinkle, 2017) Verified Chapter's 1 - 73 Complete.pdf
TEST BANK For Brunner and Suddarth's Textbook of Medical-Surgical Nursing, 14th Edition (Hinkle, 2017) Verified Chapter's 1 - 73 Complete.pdf
Gene therapy can be broadly defined as the transfer of genetic material to cure a disease or at least to improve the clinical status of a patient.
One of the basic concepts of gene therapy is to transform viruses into genetic shuttles, which will deliver the gene of interest into the target cells.
Safe methods have been devised to do this, using several viral and non-viral vectors.
In the future, this technique may allow doctors to treat a disorder by inserting a gene into a patient's cells instead of using drugs or surgery.
The biggest hurdle faced by medical research in gene therapy is the availability of effective gene-carrying vectors that meet all of the following criteria:
Protection of transgene or genetic cargo from degradative action of systemic and endonucleases,
Delivery of genetic material to the target site, i.e., either cell cytoplasm or nucleus,
Low potential of triggering unwanted immune responses or genotoxicity,
Economical and feasible availability for patients .
Viruses are naturally evolved vehicles that efficiently transfer their genes into host cells.
Choice of viral vector is dependent on gene transfer efficiency, capacity to carry foreign genes, toxicity, stability, immune responses towards viral antigens and potential viral recombination.
There are a wide variety of vectors used to deliver DNA or oligo nucleotides into mammalian cells, either in vitro or in vivo.
The most common vector system based on retroviruses, adenoviruses, herpes simplex viruses, adeno associated viruses.
Nano-gold for Cancer Therapy chemistry investigatory projectSIVAVINAYAKPK
chemistry investigatory project
The development of nanogold-based cancer therapy could revolutionize oncology by providing a more targeted, less invasive treatment option. This project contributes to the growing body of research aimed at harnessing nanotechnology for medical applications, paving the way for future clinical trials and potential commercial applications.
Cancer remains one of the leading causes of death worldwide, prompting the need for innovative treatment methods. Nanotechnology offers promising new approaches, including the use of gold nanoparticles (nanogold) for targeted cancer therapy. Nanogold particles possess unique physical and chemical properties that make them suitable for drug delivery, imaging, and photothermal therapy.
Travel Clinic Cardiff: Health Advice for International TravelersNX Healthcare
Travel Clinic Cardiff offers comprehensive travel health services, including vaccinations, travel advice, and preventive care for international travelers. Our expert team ensures you are well-prepared and protected for your journey, providing personalized consultations tailored to your destination. Conveniently located in Cardiff, we help you travel with confidence and peace of mind. Visit us: www.nxhealthcare.co.uk
Pictorial and detailed description of patellar instability with sign and symptoms and how to diagnose , what investigations you should go with and how to approach with treatment options . I have presented this slide in my 2nd year junior residency in orthopedics at LLRM medical college Meerut and got good reviews for it
After getting it read you will definitely understand the topic.
Giloy in Ayurveda - Classical Categorization and SynonymsPlanet Ayurveda
Giloy, also known as Guduchi or Amrita in classical Ayurvedic texts, is a revered herb renowned for its myriad health benefits. It is categorized as a Rasayana, meaning it has rejuvenating properties that enhance vitality and longevity. Giloy is celebrated for its ability to boost the immune system, detoxify the body, and promote overall wellness. Its anti-inflammatory, antipyretic, and antioxidant properties make it a staple in managing conditions like fever, diabetes, and stress. The versatility and efficacy of Giloy in supporting health naturally highlight its importance in Ayurveda. At Planet Ayurveda, we provide a comprehensive range of health services and 100% herbal supplements that harness the power of natural ingredients like Giloy. Our products are globally available and affordable, ensuring that everyone can benefit from the ancient wisdom of Ayurveda. If you or your loved ones are dealing with health issues, contact Planet Ayurveda at 01725214040 to book an online video consultation with our professional doctors. Let us help you achieve optimal health and wellness naturally.
5-hydroxytryptamine or 5-HT or Serotonin is a neurotransmitter that serves a range of roles in the human body. It is sometimes referred to as the happy chemical since it promotes overall well-being and happiness.
It is mostly found in the brain, intestines, and blood platelets.
5-HT is utilised to transport messages between nerve cells, is known to be involved in smooth muscle contraction, and adds to overall well-being and pleasure, among other benefits. 5-HT regulates the body's sleep-wake cycles and internal clock by acting as a precursor to melatonin.
It is hypothesised to regulate hunger, emotions, motor, cognitive, and autonomic processes.
Congestive Heart failure is caused by low cardiac output and high sympathetic discharge. Diuretics reduce preload, ACE inhibitors lower afterload, beta blockers reduce sympathetic activity, and digitalis has inotropic effects. Newer medications target vasodilation and myosin activation to improve heart efficiency while lowering energy requirements. Combination therapy, following an assessment of cardiac function and volume status, is the most effective strategy to heart failure care.
Dr. Tan's Balance Method.pdf (From Academy of Oriental Medicine at Austin)GeorgeKieling1
Home
Organization
Academy of Oriental Medicine at Austin
Academy of Oriental Medicine at Austin
Academy of Oriental Medicine at Austin
About AOMA: The Academy of Oriental Medicine at Austin offers a masters-level graduate program in acupuncture and Oriental medicine, preparing its students for careers as skilled, professional practitioners. AOMA is known for its internationally recognized faculty, award-winning student clinical internship program, and herbal medicine program. Since its founding in 1993, AOMA has grown rapidly in size and reputation, drawing students from around the nation and faculty from around the world. AOMA also conducts more than 20,000 patient visits annually in its student and professional clinics. AOMA collaborates with Western healthcare institutions including the Seton Family of Hospitals, and gives back to the community through partnerships with nonprofit organizations and by providing free and reduced price treatments to people who cannot afford them. The Academy of Oriental Medicine at Austin is located at 2700 West Anderson Lane. AOMA also serves patients and retail customers at its south Austin location, 4701 West Gate Blvd. For more information see www.aoma.edu or call 512-492-303434.
Nutritional deficiency Disorder are problems in india.
It is very important to learn about Indian child's nutritional parameters as well the Disease related to alteration in their Nutrition.
This presentation gives information on the pharmacology of Prostaglandins, Thromboxanes and Leukotrienes i.e. Eicosanoids. Eicosanoids are signaling molecules derived from polyunsaturated fatty acids like arachidonic acid. They are involved in complex control over inflammation, immunity, and the central nervous system. Eicosanoids are synthesized through the enzymatic oxidation of fatty acids by cyclooxygenase and lipoxygenase enzymes. They have short half-lives and act locally through autocrine and paracrine signaling.
6. Lower Extremity Arthrology
6
Hip Joint Complex
Introduction
The hip joint complex is the critical link between the lower extremity and the trunk. This system must
absorb and transmit enormous forces while also allowing a large arc of motion. The hip joint complex is made up
of four joints: the femoroacetabular joint, the right and left sacroiliac (SI) joints, and the pubic symphysis.
Typically, the femoroacetabular joint is referred to as the hip joint. This is the ball and socket articulation where
most of our lower extremity range of motion comes from. However; the SI joints and the pubic symphysis create
the stable ring of the pelvis and may affect how the hip can function in open and closed kinetic chain. The pelvis
is made up of two innominates created by the ileum, ischium and pubis, which are connected anteriorly at the
symphysis pubis and posterior at the right and left sacroiliac (SI) joints. The innominate bones fuse together
forming the acetabulum where the head of the femur articulates wit the pelvis. The SI joint is an articulation
between the sacrum of the spinal column and the ileum bones of the pelvis. The pubic symphysis is the
articulation between the two pubic bones of the pelvis. The common hip joint complex has three distinct
functions, it acts as attachment site for various muscles and connective tissues, supports the organs such as the
urinary bladder and intestines, and helps transmit weight from the appendicular to axial skeleton.
Muscles of the Hip Joint Complex
Category Muscle Function Origin Insertion Nerve Blood Supply
Gluteal
Region
Gluteus maximus Hip extensor
External rotator
(H)
Surface of ilium,
sacrum and coccyx
Iliotibial tract and
gluteal tuberosity
of the femur
Inferior
gluteal
(L5, S1,
S2)
Inf. & Sup. Gluteal
Gluteus medius Hip abductor
Internal rotator (H)
Surface of ilium Greater
trochanter
Superior
gluteal
Superior gluteal
Gluteus minimus Hip abductor
Internal rotator (H)
Surface of ilium Greater
trochanter
Superior
gluteal
Superior gluteal
Tensor Fascia
Latae
Med rotation,
flexion of the hip.
Abduction
Outer surface of
ilium
Iliotibial tract Superior
gluteal
Superior gluteal
Pelvic
Region
Gluteus maximus Hip extensor
External rotator
(H)
Surface of ilium,
sacrum and coccyx
Iliotibial tract and
gluteal tuberosity
of femur
Inferior
gluteal
Inf. & Sup. Gluteal
Piriformis External rotator
(H)
Sacrum Greater
trochanter
Sacral
plexus
Inf. & Sup. Gluteal
Superior gemellus External rotator
(H)
Ischial spine Greater
trochanter
Sacral
plexus
Inf. Gluteal
7. Lower Extremity Arthrology Guide 7
Inferior gemellus External rotator
(H)
Ischial tuberosity Greater
trochanter
Sacral
plexus
Inf. Gluteal
Obturator internus External rotator
(H)
Inner surface of
obturator foramen
Greater
trochanter
Sacral
plexus
Inf. Gluteal
Obturator externus External rotator
(H)
Outer surface of
obturator foramen
Greater
trochanter
Obturator Med. circumflex
femoral & Obturator
Anterior
Thigh
Pectineus Hip Flexor
Hip Adductor
Pubic ramus Upper medial
femur
Femoral Med. Circumflex
femoral & Obturator
Sartorius Hip Flexor
Hip Abductor
External rotator
(H)
Knee extensor
Anterior superior
iliac spine
Upper medial
tibia
Femoral Femoral
Rectus femoris Hip Flexor
Hip Extensor
External rotator
(H)
Upper shaft of
femur
Patellar ligament Femoral Lateral circumflex
femoral
Vastus medialis Hip Extensor
External rotator
(H)
Upper shaft of
femur
Patellar ligament Femoral Femoral
Vastus lateralis Hip Extensor
External rotator
(H)
Upper shaft of
femur
Patellar ligament Femoral Lateral circumflex
femoral
Vastus
intermedius
Hip Extensor
External rotator
(H)
Upper shaft of
femur
Patellar ligament Femoral Lateral circumflex
femoral
Category Muscle Function Origin Insertion Nerve Blood Supply
Medial
Thigh
Gracilis Knee Flexor
Hip Adductor
Pubic ramus Upper medial
tibia
Obturator Med circumflex
femoral & obturator
Adductor magnus Hip Adductor
External rotator
(H)
Pubic ramus Posterior surface
of shaft of femur
Obturator Med circumflex
femoral & obturator
Adductor brevis Hip Adductor
External rotator
(H)
Pubic ramus Posterior surface
of shaft of femur
Obturator Med circumflex
femoral & obturator
Adductor Longus Hip Adductor
External rotator
(H)
Pubic ramus Posterior surface
of shaft of femur
Obturator Med circumflex
femoral & obturator
Posterior
Thigh
Semitendinosus Hip Extensor
Knee Flexor
Ischial tuberosity Medial condyle
of tibia
Tibial Perforating br. Of
deep femoral
Semimembranosus Hip Extensor
Knee Flexor
Ischial tuberosity Medial condyle
of tibia
Tibial Perforating br. Of
deep femoral
Long head of
biceps femoris
Hip Extensor
Knee Flexor
External rotator
(H)
Ischial tuberosity Fibular head Tibial Perforating br. Of
deep femoral
Short head of
biceps femoris
Knee Flexor
External rotator
(H)
Lateral shaft of
femur
Fibular head Fibular Perforating br. Of
deep femoral
Hamstring part of
adductor magnus
Hip Extensor Ischial Tuberosity Medial shaft of
femur (adductor
tubercle)
Tibial Perforating br. Of
deep femoral
8. Lower Extremity Arthrology
8
Symphysis Pubis Joint
Overview
The symphysis pubis joint primarily acts as a stabilizer to allow some mobility in the pelvic ring without
compromising stability of the lower extremity and trunk. It is a
synarthrosis fibrocartilaginous joint, joined together by a fibrocartilaginous
disc; called the interpubic disc. The interpubic disc is situated between two
layers of hyaline cartilage that line the medial articular surfaces of the two
pubic bones. The joint is further reinforced by a series of ligaments and
tendinous sheaths that stabilize the symphysis pubis and prevent excessive
separation, compression, shift, or rotation from occurring.
The symphysis pubis helps to disperse force transmitted from the lower extremity up through the pelvic
ring to the axial skeleton during gait and impact activity. It is not commonly injured, but joint laxity during
pregnancy and postpartum can result in pelvic dysfunction and symphysis pubis pain. As it is not a synovial joint,
no joint capsule exists and instead the joint articulates via the interpubic disc. This joint does not act in
physiological kinematics and arthrokinematics beyond a few degrees of shift or rotation are indicative of
dysfunction and may lead to pain. Even so, the symphysis pubis is key to allowing pelvic ring pliability during
childbirth while maintaining a stable structure for large force distribution in everyday activity.
Tissue Layers
• Skin
o Epidermis
o Dermis
o Hypodermis
• Subcutaneous tissue
o Camper’s Fascia
o Scarpa’s Fascia
• Rectus Abdominis Sheath
o External Oblique mm. and aponeurosis
o Internal Oblique mm. and aponeurosis
o Transversus Abdominis mm. and aponeurosis
o Rectus abdominis mm.
o Transversalis Fascia
Figure
1
Interpubic
disc
9. Lower Extremity Arthrology Guide 9
• Tendons
o Adductor Brevis
o Adductor Longus
o Pectineus
o Gracilis
o Adductor magnus
o Quadratus
o Obturator externus
• Neurovasculature
o Obturator aa. and vv.
o Inferior epigastric aa. and vv.
o Pudendal nn.
o Genital branch of genitofemoral nn.
o Iliohypogastric/ilioinguinal nn.
• Ligaments
o Superior pubic ligament
o Anterior pubic ligament
o Inferior pubic (arcuate) ligament
o Posterior pubic ligament
o Inguinal Ligament
• Bones
o Pubic Bones
• Interpubic disc
Joint Motion
Joint Motion* Primary Movers Secondary Movers
2mm Shift (inferior/superior) Gravity, ground reaction force through LE
Adductor brevis, longus, gracilis, rectus abdominis,
external oblique aponeurosis
N/A
1° Rotation Same* N/A
*Due to the stability of the pubic symphysis, no muscles act directly on it. Rather, gravity and ground reaction forces indirectly shift and
rotate its approximation as well as conjunct movement of muscles that attach here.
Biomechanics
The two pubic bones have medial hyaline cartilage-covered articulating surfaces. They articulate at
midline as reinforced by many ligaments and fibrocartilage connections. The articulating surfaces contain small
ridges to increase stability and resist shear forces. The interpubic
disc lies in between the joint surfaces providing a binding surface.
The joint is primarily subject to compression forces at its superior
border and tensile forces at its inferior border with everyday
activity of sitting and walking; especially during single limb
stance due to activity of the rectus sheath superiorly and the Figure
2
Muscular
reinforcement
of
pubic
symphysis
10. Lower Extremity Arthrology
10
adductor tendons inferiorly as Figure 2 illustrates. The joint allows up to 2mm of translation in the sagittal plane
and 1° of rotation. The average displacement of the pubic bones in any direction (most prominently during single
limb stance) is 1-2mm higher in women who have bore children compared to both men and nulliparous women.
The joint is strongly reinforced via four ligamentous structures. According to Ibrahim & El-Sherbini in 1961, the
ligaments from strongest to weakest were anterior: inferior: superior; with no data provided on the posterior pubic
ligament. The strength of these ligaments were strongest in men, then nulliparous women, then women who had
children, and weakest in women during their third trimester of pregnancy.
Joint Configuration
According to Becker et al. the most current anatomical and arthrodial evidence reported on the symphysis
pubis is from 1990. In Becker et al.’s 2010 systematic review, they concluded that the articular surfaces of the
pubic bones are slightly convex, oval shaped and running posteroinferiorly in a craniocaudal direction.
Posteriorly the surfaces are parallel but separate anterior and superiorly. The subchondral bone begins rough and
uneven in childhood, but is relatively smooth by 30 years of age. As degenerative changes occur in late adulthood,
the subchondral bone surface roughens again by age 60.
Ligaments of the Symphysis Pubis
Ligament Attachments Function Other constraints
Superior Pubic Ligament Bilateral pubic crests as far laterally as pubic
tubercles, interpubic disc, pectineal ligament,
linea alba
Controversial but most likely
reinforcement of superior
portion of joint
Stability
Inferior Pubic Ligament
(subpubic, arcuate)
Inferior pubic rami bilaterally, interpubic disc Reinforce inferior portion of
joint
Stability
Anterior Pubic Ligament Anterior pereosteum of pubic bones bilaterally.
Interpubic disc
Reinforce anterior symphysis
pubis
Strongest ligament
of symphysis pubis.
Posterior pubic ligament A few thin fibers spanning posterior symphysis
pubis, blending with pubic rami pereosteum and
superior and inferior pubic ligaments.
Reinforce symphysis pubis
joint
Stability
Interpubic Disc
(fibrocartilaginous)
Medial articular surfaces of bilateral pubic bones,
fused with superior, inferior, anterior, posterior
pubic ligaments
Withstand compressive and
tensile stresses
Stability, maintain
pelvic ring integrity
Figure
3
Bony
features
of
symphysis
pubis
11. Lower Extremity Arthrology Guide 11
Common Joint Pathology
Parturition-Induced Pelvic Instability. The symphysis pubis is relatively immobile and so most
pathologies related to its anatomy are due to excessive mobility. The most common pathology of the symphysis
itself is parturition-induced pelvic instability. This is excessive mobility and pain of the symphysis pubis due to
increases in relaxin and progesterone hormones during and after childbirth in women. The symphysis can widen
in women after childbirth 3-7mm and is treated conservatively with a brace to promote compression of the
symphysis, muscular strengthening to increase dynamic stability and modified activity.
Pelvic Fracture. In addition to childbirth, acute trauma can cause mass instability of the symphysis pubis.
An open book pelvic fracture is a fracture to the pelvic ring induced from an anterior to posterior compression
force. This causes the symphysis pubis to separate and open the pelvis up like a book. This fracture is often
accompanied by sacroiliac joint pain and pathology. This is a devastating injury necessitating surgery to repair
arteries and manage blood loss as well as reapproximate the symphysis pubis.
Osteitis Pubis. An additional common pathology of the symphysis pubis is osteitis pubis. This is
inflammation of the symphysis pubis due to a variety of irritants. The most common causes of osteitis pubis are
high level of athletic activity disrupting adductor tendon attachments to the pubis, childbirth disruption of the
joint, or secondary effects of urologic or gynecologic surgery.
Sacroiliac Joint
Overview
Sacroiliac (SI) joint is the articulation between the ilium and the sacrum. This joint is designed for
stability and transfer of either light loads or heavy loads. These loads are
transferred through vertebral column, lower extremities, and the ground.
The SI joint is made up of the articulation of the sacrum with the
ilium on each side. The articular surfaces are ear shaped, containing
irregular ridges and depressions. The concave sacral surface is
Figure
4
Sacroiliac
bony
structure
12. Lower Extremity Arthrology
12
covered with thick hyaline cartilage and the convex iliac surface is lined with thin fibrocartilage. The joint
is comprised of strong and dense ligamentous structures that contribute to the SI joint being one of the
most stable joints in the body. Numerous muscles also attach to the SI joint that assist in stabilizing the
joint.
The SI joint configuration undergoes changes during aging that are related to dysfunction. In
adolescence the SI joint is mostly synovial with smooth articular surfaces. This smooth surface of the joint
in early childhood permits gliding motions in all directions. Through puberty and entering adulthood, the joint
characteristics change. The joint becomes part syndesmosis and part synovial. The articular surfaces also
change from smooth to more rough and irregular between puberty and adulthood. The irregular and rough
surface changes happen on both the articular surfaces and the subchondral bone. The joint also becomes
less mobile through the aging process. The ligaments that cover the joint become more fibrotic and less
elastic. The hyaline cartilage that covers the concave sacral surface thins and may cause adhesions to occur
between the sacrum and the ilium. Due to these changes, motion (primarily rotation) becomes minimal and
the joint becomes more mature and stable.
Anatomical features of the joint also differ with gender. The female sacrum is shorter, wider, and
more posteriorly curved than the male sacrum to provide more room for the passage of the newborn through the
birth canal during childbirth. The male sacrum is long, narrow, straighter, and has a more pronounced sacral
promontory. These differences are due to greater imposed forces on the joint in males compared to females
according to Vleeming et al. The sacroiliac ligaments in women are more elastic than men’s, allowing the
mobility necessary for childbirth.
Neurovasculature. Blood supply to the joint is derived from iliolumbar, superior gluteal, and lateral
sacral arteries. The sacroiliac joint is also well innervated. According to Forst SL; histological analysis of the
sacroiliac joint has verified the presence of nerve fibers within the joint capsule and adjoining ligaments. It has
been variously described that the sacroiliac joint receives its innervations from the ventral rami of L4 and L5, the
superior gluteal nerve, and the dorsal rami of L5, S1, and S2.
13. Lower Extremity Arthrology Guide 13
Tissue Layers
• Integumentary
o Epidermis
o Dermis
o Hypodermis
• Superficial fascia
o Subcutaneous tissue
o Stored fat
o Loose connective tissue
o Neurovasculature
• Muscles/Fascia
o Thoracolumbar fascia
§ Posterior layer
§ Lateral raphe
§ Middle layer
§ Anterior Layer
o Erector Spinae
§ Iliocostalis
§ Longissimus
o Gluteus maximus
o Gluteus medius
o Gluteus minimus
o Piriformis
o Iliacus
o Psoas Major
• Ligaments
• Joint articular surfaces
Joint Motions
Joint Motion* Associated Muscles
Stability Biceps femoris, Gluteus maximus, Latissimus dorsi, Iliacus, Piriformis Erector spinae, Lumbar multifidi, Rectus
abdominis, Internal abdominal obliques, Transversus abdominis
Nutation Biceps femoris, Erector spinae, Rectus abdominis
Counternutation Rectus femoris, Tensor fascia latae, Adductor longus, Pectineus
* It should be noted that movement at the SI joint occurs secondarily due to movement of the innominate bones. No muscle directly acts on
the SI joint.
Biomechanics
The articular surface of the ilium is convex and the articular surface of the sacrum is slightly concave.
The SI joint permits a small amount of motion that varies among individuals. The smooth SI joint surfaces in
early childhood permit gliding motions in all directions, which is typical of a synovial plane joint. However, after
puberty, the joint surfaces change their configuration and motion in the adult is restricted to a few millimeters.
Due to the congruency of the joint, movement is described as the concave sacrum moving on the convex ilium.
14. Lower Extremity Arthrology
14
When the movement does occur at the ilium, the movement that describes the movement at the sacrum is
described as nutation and counternutation.
These motions occur around its mediolateral
axis at the level of S2 and are limited to the
near sagittal plane. Nutation occurs as the
sacrum moves anteriorly and inferiorly while
the coccyx moves posteriorly relative to the ilium.
Nutation occurs with a posterior iliac tilt. Counternutation is simply the opposite and occurs when the sacrum
moves posteriorly and superiorly while the coccyx moves anteriorly relative to the ilium. Counternutation occurs
with anterior pelvic tilt. Ilium-on-sacral rotation, sacral-on ilium rotation, or complimentary motion of both can
accomplish nutation and counternutation. These motions help transfer the forces between the axial skeleton and
lower extremities.
During gait, the SI joint is very important as it is the location for force transmission from the trunk to the
ground and from the ground to the trunk. In order for the forces to be transferred efficiently the joint has to be
stable. Stability of the joint comes from strong, fibrous ligaments, the irregular articular surfaces of the ilium and
sacrum, and muscular stabilizers. Stability of the SIJs is extremely important because these joints must support a
large portion of the body weight. In normal erect posture, the weight of head, arms, and trunk (HAT) is
transmitted through the fifth lumbar vertebra and lumbosacral disk to the first sacral segment. The joint must
support significantly more than the weight of the body if an individual is lifting or carrying weighted objects
As noted earlier the SI joint is very stable joint with minimal movement. The movement that does occur
at the joint is very important for stress relief during walking, running, and during childbirth in women. During
walking, the pelvis rotates from side to side as the lower extremity changes from a position of flexion to
extension. In normal gait with typical speed, the heel of advancing lower limb strikes the ground as the toes of the
opposite limb are still in contact with the support. It is this point in gait that the ligaments and muscles at the hips
create oppositely directed torsions on the right and left iliac crests. Torsions are most notable in sagittal and
Figure
5
Nutation
and
Counternutation
of
SI
joint
15. Lower Extremity Arthrology Guide 15
horizontal plane. If the SI joint was a solid and continues structure, the SI joint would not be able to dissipate
damaging stress and the pelvic ring would be damaged with everyday activity.
Gravity is the first line of stability for the SI joint. In an upright position the bodies center of mass is just
anterior to S2, which is the midpoint between an imaginary line connecting the two SI joints The downward force
of gravity that is a result from the body weight passing through the vertebra forces the trunk downwards on the
sacrum while the joint transfers weight from the lower extremity to the spine. This creates a nutation moment
about the joint. At the same time, ground reaction forces act on the femoral head, causing an upward directed
compression force through the acetabulum. This forces the ilium to rotate posteriorly. The nutation moment
created by gravity and the ground reaction force causing the ilium to rotate posteriorly creates a locking
mechanism. This locking mechanism relies primarily on gravity and congruity of the joint surfaces rather than the
extra-articular structures such as ligaments and muscles.
Ligaments also provide stability to the joint as the ligaments
of the sacrum are some of the strongest and toughest ligaments in the
body that are difficult to tear, stretch, and mobilize. The primary
stabilizing ligaments of the SI joint are the interosseous sacroiliac,
anterior sacroiliac, iliolumbar, and posterior sacroiliac ligaments as
illustrated in Figure 6 and 7. The secondary ligaments that stabilize
the sacrum are the sacrotuberous and sacrospinous ligaments.
The interosseous sacroiliac ligament strongly and rigidly
binds the sacrum with the ilium. The major function of the
interosseous sacroiliac ligament is to prevent abduction or distraction
of the sacroiliac joint. It is also the interosseous sacroiliac ligaments
that are responsible for transferring the weight from the axial
skeleton to the appendicular skeleton. The anterior sacroiliac
Figure
7
Ligaments
of
Posterior
Sacrum
Figure
6
Ligaments
of
Anterior
Sacrum
16. Lower Extremity Arthrology
16
ligaments are thin anterior parts of the fibrous capsule of the synovial part of the joint. Iliolumbar ligaments blend
in with the anterior sacrospinous ligaments and radiate from transverse processes of L5 vertebra to the ilia.
Posterior sacroiliac ligaments connect the PSIS with the lateral crests of the third and fourth segments of the
sacrum and are very strong and tough. The short band of the posterior sacroiliac ligament also provides stability
against all movements. Due to the posterior sacroiliac and interosseous sacroiliac ligaments running obliquely
upward and outward from the sacrum, the axial weight pushing downward on the sacrum forces the ilia medially.
This causes the sacrum to be compressed between the ilia and locks the irregular but congruent surfaces of the
sacroiliac joints together. Iliolumbar ligaments act as accessory ligaments and assist in this mechanism.
Sacrotuberous and sacrospinous ligaments offer secondary support posteriorly. They do not actually cross the
joint, but they indirectly assist stabilization by resisting nutation.
Stability is adequate for activities that involve relatively low static loading such as sitting and standing.
For larger more dynamic loading, the SI joint is reinforced by ligaments and muscles. Nutation torque stretches
many of the connective tissues at the SI joint. Increased tension in these ligaments further compresses the surface
of the SI joint and thereby adds to their transarticular stability.
In addition to ligaments, several hip and trunk muscles reinforce and stabilize the sacroiliac joints. Such
muscles are erector spinae, lumbar multifidi, rectus abdominis, obliques abdominis internus and externus,
transversus abdominis, gluteus maximus, latissimus dorsi, iliacus and piriformis. These muscles stabilize the SI
joint by (1) generating active compressive forces against the articular surfaces, (2) increasing magnitude of
nutation torque and subsequently engaging the active locking mechanism, and (3) pulling on connective tissues
that reinforce the joints. As an example, let's consider erector spinae and bicep femoris. Erector spinae muscle
will rotate the sacrum anteriorly and biceps femoris will rotate the ileum posteriorly and thus both of these actions
create nutation. It is then safe to assume that anterior tilt of the pelvis will create counternutation. The muscles
that create anterior tilt at the pelvis could create counternutation at the sacrum. Some of these muscles include
iliopsoas, rectus femoris, tensor fascia latae, adductor longus, and pectineus.
17. Lower Extremity Arthrology Guide 17
Mechanical stability of the SI joint is provided by thoracolumbar fascia. Thoracolumbar fascia consists of
three different layers that surround the posterior muscles of the lower back. Those layers are anterior, middle, and
posterior. The anterior and middle layers are anchored medially to the transverse processes of the lumbar
vertebrae and inferiorly to the iliac crest. The posterior layer covers the posterior surface of the erector spinae and
latissimus dorsi muscle. The posterior layer attaches to the spinous processes of lumbar vertebrae, the sacrum, and
the ilium, adding stability to the SI joint. Posterior layer stability to the joint is provided by erector spinae muscle
creating a nutation torque by rotating the sacrum anteriorly and thus locking the joint and stabilizing it. Medial
and posterior layers of thoracolumbar fascia fuse at their lateral margins and thus blend with internal oblique and
transversus abdominis musculature. The internal oblique and transversus abdominis muscles compress the ilia
toward the sacrum, increasing joint stability. Stability is further enhanced by the superficial attachments of
latissimus dorsi and gluteus maximus to thoracolumbar fascia resulting in an increased compression of the SI
joint. The iliacus and piriformis muscles provide secondary stability at the SIJ articulation by attaching directly to
the capsule or margins of the SI joint.
Pregnancy plays a large role in SI joint biomechanics in women. The release of relaxin during pregnancy
decreases the intrinsic strength and rigidity of collagen. The action of relaxin is responsible for the softening of
the ligaments supporting the SI joint and the symphysis pubis. This causes the joint to become more mobile, less
stable and increase the size of pelvic outlet during childbirth. There is less resistance to these hormonal-induced
changes due to the smoother articular surfaces of the SI joints of women being pregnant.
Joint Configuration
The SI joint is the articulation between the auricular surface of the sacrum and the ilium. SI joint is
formed within sacral segments S1, S2 and S3. As mentioned previously the articular surface of the ilium is
convex and faces anteriorly and inferiorly. The articulating surface of the sacrum is concave and faces more
posterior and inferiorly compared to the ilium. The articulating surfaces on the sacrum are C-shaped and are
located on the sides of the fused sacral vertebrae lateral to the sacral foramina. The SI joint consists of an anterior
synovial joint and a posterior syndesmosis. The articular surfaces of this synovial joint have irregular but
18. Lower Extremity Arthrology
18
congruent elevations and depressions that interlock. The articulating surface of the sacrum is covered by hyaline
cartilage. The ilium-articulating surface is covered by fibrocartilage. The overall mean thickness of the sacral
cartilage is greater than that of the iliac cartilage.
Ligaments of the Sacroiliac
Ligaments Attachments Function Associated
Constraints
Anterior
Sacroiliac
3rd sacral segment to the lateral side of the
pre-auricular sulcus
Primary source of stability;
reinforce the anterior side of the SI
joint
Nutation
Iliolumbar Tip and anteroinferior
aspect of the transverse process of
L5 to (1) the posterior margin of the iliac fossa and
(2) to the iliac crest anterior to the sacroiliac joint
Primary source of stability;
reinforce the
anterior side of the SI joint;
stabilizes L5 on the ilium
Nutation
Interosseous
Sacroiliac
Deep portion: superior and inferior bands from
depressions posterior
to the sacral auricular surface to those on the iliac
tuberosity
Superficial: sheet connecting the poster superior
margin posterior to the sacral
auricular surface to the corresponding margins of the
iliac tuberosity
Forms part of the sacroiliac
articulation (syndesmosis): binds
the sacrum to the ilium; Primary
source of stability
Stability in all
motions
Posterior
sacroiliac (short
and long)
Short: posterior- lateral side of the sacrum to the
ilium, near the iliac tuberosity and the PSIS
Long: 3rd and 4th sacral segments to PSIS
Primary source of stability;
reinforce the
posterior side of the SI joint
Short: all pelvic and
sacral movement
Long:
Counternutation
Sacrotuberous Posterior superior iliac spine (PSIS), lateral sacrum,
and coccyx, attaching to the ischial tuberosity
Secondary source of stability Nutation
Sacrospinous Lateral margin of caudal end of sacrum and coccyx,
attaching to the ischial spine
Secondary source of stability Nutation
Common Joint Pathology
Osteoarthritis. As with most other joints in the body, the SI joints have a cartilage layer covering the
bone. When this cartilage is damaged or worn away osteoarthritis may occur. This could cause severe pain and
discomfort for the patient. As the condition progresses at the SI joint, the joint cleft narrows and osteophytes may
form within the ligaments. These osteophytes could ossify the ligaments and fuse the sacrum to the ilium and
cause complete immobilization of the SI joint.
Parturition-Induced SIJ Pain. Laxity of the sacroiliac joint could also cause symptomology. Women
are more likely to experience this than men because of childbearing. During childbirth, release of relaxin and
progesterone cause more mobility and an increase in synovial fluid. Hypermobility and ligament laxity could
cause increased risk of injury such as dislocation and pelvic girdle pain postpartum.
19. Lower Extremity Arthrology Guide 19
Ankylosing spondylitis. Ankylosing spondylitis is an inflammatory condition of the joints, especially in
the spinal column. Inflammation within joints can lead to severe pain and discomfort. In very severe cases the
inflammation can induce fibrosis and cause the bones to fuse, resulting in massive restrictions to mobility. Typical
patient complaints are persistent low back pain and stiffness that is worse in the morning and night, but improves
with activity. Patients often complain of unilateral or alternating buttock pain. Also, patients tend to complain of
pain during the second half of sleep only. Differential diagnosis for ankylosing spondylitis include stress fracture,
muscle spasm, lumbar disk herniation, osteoarthritis, gout, cancer, infection, and rheumatoid arthritis. The disease
most commonly presents in young males, ages 15-30 years old.
Femoroacetabular Joint
Overview
The femoroacetabular (FA) joint, more commonly known as the hip joint is a ball and socket joint and is
created with an articulation between the femoral head and the socket of the
acetabulum on the pelvis with three degrees of freedom. Three bones of the pelvis;
the ischium, ilium, and pubis form the acetabulum. The femur is the longest and
strongest bone in the body. The femoral head projects medially and slightly
anteriorly for an articulation with the acetabulum. The femoral head is secured
within the acetabulum by an extensive set of connective tissues and muscles. Thick
layers of articular cartilage, muscle, and cancellous bone in the proximal femur help reduce the large forces that
cross the joint. The hip is required to operate in both open and close kinetic chain and so stability is very
important at this joint. The stability to the joint mostly comes from the joint configuration as well as the
ligamentous design. Muscles also contribute to joint stability as the joint must
withstand high loads during activity such as running, jumping, and walking.
Neurovasculature. The femoroacetabular joint receives its blood supply
from the artery to the head of the femur, but the primary blood supply to the joint
Figure
8
Femoroacetabular
Joint
Surfaces
Figure
9
Bones
of
Acetabulum
20. Lower Extremity Arthrology
20
comes from the medial and lateral circumflex femoral arteries, which come off the deep femoral artery. The joint
is also highly innervated as the sacral and lumbar plexus are close in proximity to it and provide numerous
innervating branches. The joint gets innervations from femoral nerve (anteriorly), obturator nerve (inferiorly),
nerve to quadratus femoris (posterior), and the superior gluteal nerve (superior).
Tissue Layers
• Integumentary
o Epidermis
o Dermis
o Hypodermis
• Subcutaneous tissue
o Fascia lata
o Subcutaneous adipose tissue
• Muscle
o Anterior compartment
§ Pectineus
§ Iliopsoas
§ Rectus femoris
§ Sartorius
o Medial compartment
§ Adductor longus
§ Adductor brevis
§ Adductor magnus
§ Gracilis
§ Obturator externus
o Posterior compartment
§ Semitendinosus
§ Semimembranosus
§ Biceps femoris (long head)
o Gluteal region
§ Gluteus maximus
§ Gluteus medius
§ Gluteus minimus
§ Tensor fasciae latae
§ Piriformis
§ Obturator internus
§ Superior gemellus
§ Inferior gemellus
§ Quadratus femoris
• Ligaments and joint capsule
• Joint articular surfaces and deep ligaments
21. Lower Extremity Arthrology Guide 21
Joint Motions
Biomechanics
Since the hip is a ball and socket joint, it is capable of a variety of motions in different planes. The
femoral head is convex and the acetabular socket is concave. The hip joint is capable of working in both open
chain and closed chain positions. In open chain, the femur tends to move on the pelvis in order to create motion.
Since the femur is moving on the pelvis, the convex is moving on the concave, the roll and glide of the femoral
head are in opposite directions. The hip has 120 degrees of flexion in the sagittal plane when the femur spins
around the mediolateral axis. In the frontal plane of open chain movement, the hip has about 40 degrees of
abduction and 25 degrees beyond the neutral line of adduction around the anteroposterior axis. The femur will roll
superior and glide inferior for abduction
and will roll inferior and glide superior for
adduction. In the sagittal plane, the hip also
has 20 degrees of extension with the femur
spinning around the mediolateral axis.
Finally, in the transverse plane, the femur
Joint
Motion
Primary Movers Secondary Movers
Flexion Iliopsoas, Sartorius, Tensor fasciae latae, Rectus
femoris, Adductor longus, Pectineus
Adductor brevis, Gracilis, Gluteus minimus (anterior fibers)
Extension Gluteus maximus, Biceps femoris (long head),
Semitendinosus, Semimembranosus, Adductor magnus
(posterior head)
Gluteus medius (posterior fibers), Adductor magnus (anterior
head)
Abduction Gluteus medius, Gluteus minimus, Tensor fasciae latae Piriformis, Sartorius
Adduction Pectineus, Adductor longus, Gracilis, Adductor brevis,
Adductor magnus
Biceps femoris (long head), Gluteus maximus (lower fibers),
Quadratus femoris
Internal
rotation
NA Gluteus minimus (anterior fibers), Gluteus medius (anterior
fibers), Tensor fasciae latae, Adductor longus, Adductor
brevis, Pectineus
External
rotation
Gluteus maximus, Piriformis, Obturator internus,
Superior gemellus, Inferior gemellus, Quadratus
femoris
Gluteus medius (posterior fibers), Gluteus minimus (posterior
fibers), Obturator externus, Sartorius, Biceps femoris (long
head)
Figure
10
Muscle
Actions
at
Sacroiliac
Joint
22. Lower Extremity Arthrology
22
can rotate internally about 35 degrees and externally about 45 degrees around the long axis of the femur. During
external rotation, the femoral head rolls posteriorly and glides anteriorly and during internal rotation the femoral
head rolls anterior and glides posterior. In closed chain, the arthrokinematics flip as the roll and glide of the
acetabulum on the femur are in the same direction because the concave surface is moving on the convex surface.
The pelvis may also move in all three planes around all three axes, although the motions have different
names, and there is a smaller range available. In the frontal plane in closed chain, the pelvis can abduct away from
the femur about 30 degrees and adduct toward the femur about 20 degrees from neutral around the anteroposterior
axis. In closed chain, a superior roll and glide creates abduction, while an inferior roll and glide creates adduction.
In the sagittal plane, the pelvis is capable of anteriorly tilting 30 degrees, and posteriorly tilting 15 degrees by
spinning around the mediolateral axis. Finally, in the horizontal plane, the pelvis can internally and externally
rotate about 15 degrees in each direction, with a total arc of 30 degrees of motion around the transverse axis.
During internal rotation, the acetabulum must anteriorly roll and glide. The opposite is true to create external
rotation
The FA joint has very complex biomechanics. Motion that occurs at the hip joint occurs either in open
chain or in closed chain. In open chain the femur moves on the acetabulum, but in closed chain the acetabulum
moves on the femur. Let's take hip flexion for example, we can take our thigh into flexion while keeping the
pelvis stable, this constitutes as open chain. Closed chain hip flexion would occur when the trunk moves into
flexion while keeping the lower limb stable. When considering movement done on a stable pelvis, we must
consider lumbopelvic rhythm due to the close relationship between the hip and the lumbar spine. The movement
that occurs is in the sagittal plane and is considered to be either ipsidirectional lumbopelvic rhythm or
contradirectional rhythm. Ipsidirectional lumbopelvic rhythm describes a movement in which the lumbar spine
and pelvis rotate in the same direction amplifying overall trunk motion. An example of this motion would be
reaching down to pick something from the ground. Contradirectional rhythm describes a movement in which the
lumbar spine and pelvis rotate in opposite direction. This type of movement is important as it allows for
separation of the pelvis and lumbar spine during activities where the head and neck need to maintain neutral
23. Lower Extremity Arthrology Guide 23
position. Other motions that occur in closed chain are anterior and posterior pelvic movements. Pelvic tilting is
defined based on the position of the anterior superior iliac spine (ASIS) of the pelvis. When the ASIS moves
anterior and inferior, it is considered an anterior pelvic tilt and results in hip flexion. When the ASIS moves
posterior and superior, it is considered a posterior pelvic tilt and results in hip extension.
Since the hip is a ball and socket joint there is three degrees of freedom and thus mobility will be
influenced by muscular activation. We will first discuss hip flexion of the joint. Iliopsoas, sartorius, tensor fascia
latae, rectus femoris, adductor longus, and pectineus are all considered to be primary hip flexors in an open chain
position. The main hip flexor muscles out of these would have to be iliopsoas due to its large size, line of pull,
and cross-sectional area. The iliopsoas tendon averts posteriorly to its distal attachment. In full hip extension, this
increases the tendon's angle of insertion creating an optimal line of pull. The secondary hip flexors (adductor
brevis, gracilis, and the anterior fibers of gluteus minimus) do not have direct lines of pull into hip flexion, but
they can produce some force in that direction. Additionally, any muscle that is considered a hip flexor in the open
chain position can also produce an anterior pelvic tilt in closed chain. An anterior pelvic tilt is also achieved by
force coupling that occurs between the hip flexors and back extensors on a fixed femur.
In the open chain position, gluteus maximus, the hamstrings (biceps femoris (long head), semitendinosus,
and semimembranosus), and the posterior head of the adductor magnus are considered to be primary hip
extensors. Gluteus maximus is considered to be the primary hip extensor due to its large cross sectional area, line
of pull, and moment arm. Adductor magnus (posterior part) is also considered to be a primary mover due to its
large moment arm. It is at 70 degrees at hip flexion and beyond that most adductors (exception to pectineus) are
capable of assisting with hip extension. The hamstring group is also primary mover due to the line of pull and
large moment arm. All three of those muscles are considered to be the primary movers for hip extension. The
posterior fibers of the gluteus medius and the anterior head of the adductor magnus are secondary movers into hip
extension. Neither one of these muscles has a great line of pull into extension from the anatomical position.
Additionally, the posterior fibers of gluteus medius do not have as much cross sectional area as the other hip
extensor muscles. Similar to the hip flexors, the hip extensors in open chain are all capable of producing a
24. Lower Extremity Arthrology
24
posterior pelvic tilt in closed chain. A force couple between the abdominal muscles and the hip extensors creates
this motion. Additionally, the hip extensors are responsible for eccentrically controlling a forward lean of the
body. The primary extensor muscle group that is responsible for this is the hamstrings. As the body leans forward
the displacement of body weight moves farther in front of the hips requiring a greater activation from the
hamstrings. This is because the moment arm of the gluteus maximus is decreased as the hip flexes, but the
moment arm of the hamstrings is increased.
The primary movers into hip adduction are pectineus, adductor longus, gracilis, adductor brevis, and
adductor magnus. The adductors also are able to work in all three planes; not just the frontal plane. This largely
has to do with their distal attachment not being located precisely in midline. The biceps femoris (long head),
gluteus maximus (lower fibers), and quadratus femoris are all considered to be secondary movers into adduction
because some of their fibers have a line of pull in this direction so they can produce some amount of force into
adduction. Adductors also assist in internal rotation of the hip joint.
The primary hip abductors are the gluteus medius, gluteus minimus, and tensor fasciae latae. The
secondary abductors of the hip joint are considered to be the piriformis and sartorius. Gluteus medius is
considered the main hip abductor. The distal attachment of gluteus medius causes it to have the largest moment
arm of all the other abductors. Gluteus medius also has the largest cross sectional area out of all the other
abductors making it the primary mover in abduction. Gluteus minimus occupies 20% of the total abductor
moment. Tensor fasciae latae occupies 11% of total abductor moment. The hip abductors also contribute to hip
internal rotation. The abductor torque produced by the hip abductor muscles is essential to the control of the
frontal plane pelvic-on-femoral kinematics during walking. During the
stance phase the hip is stabilized over the relative fixed femur by the hip
abductors. The hip abductors also play a crucial role during the single-limb
support phase of gait. Without adequate torque on the stance limb, the
pelvis and the trunk may drop toward the side of the swinging limb. The
Figure
11
Trendelenburg
Sign
25. Lower Extremity Arthrology Guide 25
observation of a contralateral hip drop during gait is known as a Trendelenburg gait pattern, and is due to lack of
strength or control of the abductor muscles.
External rotation of the hip is done by gluteus maximus, piriformis, obturator internus, superior gemellus,
inferior gemellus, and quadratus femoris. Gluteus maximus has the largest cross-sectional area and so is
considered the primary external rotator of the hip. The others have fairly small cross-sectional areas but have a
direct line of pull and they provide stability to the posterior aspect of the joint. The gluteus medius (posterior
fibers), gluteus minimus (posterior fibers), obturator externus, sartorius, and biceps femoris (long head) are all
secondary movers into external rotation, due to their indirect lines of pull. Hip external rotators are most
functional during closed chain movements such as cutting, pivoting, and changing direction very rapidly. The
external rotators can also function in open chain movements. Open chain external rotation of the hip will rotate
the foot so the toes point more laterally and the heel is more medial.
The last motion produced by the hip is internal rotation. There are no primary internal rotators of the hip.
This is due to the need of muscles to be oriented in a horizontal plane of motion during standing and that does not
occur. There are many secondary hip internal rotators, though. Secondary movers are gluteus minimus (anterior
fibers), gluteus medius (anterior fibers), tensor fasciae latae, adductor longus, adductor brevis, and pectineus. As
the hip moves from 0 degrees to 90 degrees of flexion, the line of pull and moment arm of many of these muscles
becomes more optimally oriented to create internal rotation at the hip. As the hip moves into 90 degrees of
flexion, some external rotators change their action and assist with internal rotation.
Joint Configuration
During weight bearing the hip must translate immense loads; its closed kinetic chain kinematics help it
provide stability. To promote congruency and stability the acetabular socket of the hip joint is fairly deep. The
acetabular labrum also helps promote stability as it deepens the socket of the joint by an additional 30%. The
labrum also forms a seal around the joint to maintain negative intra-articular pressure and thus create suction that
prevents distraction of the joint. The seal also holds the synovial fluid within the joint and enhances the
26. Lower Extremity Arthrology
26
lubrication of the joint and its ability to dissipate load. The acetabulum and the femoral head also have thick
layers of articular cartilage to prevent wear and tear of the joint surfaces.
The bony anatomy of the hip is somewhat variable and may affect how the
joint can function. Two measurements of the femur are considered: the angle of
inclination and femoral torsion. The angle of inclination occurs in the frontal plane
between an axis through the femoral head and neck and the longitudinal axis of the
femoral shaft. At birth, the angle of inclination is about 140 to 150 degrees. Due to loading across the femoral
neck, the angle reduces to 125 degrees near adulthood. When the angle of inclination varies greatly from typical,
it is referred to either as coxa vara or coxa valga. When the angle is less than 125 degrees it is described as coxa
vara and can lead to genu valgum at the knee. An angle greater than 125 degrees is considered to be coxa valga
and can lead to genu varum at the knee. These varying conditions of the angle of inclination are illustrated in
Figure 12. Femoral torsion occurs in the transverse plane between an axis through the femoral head and neck and
an axis through the distal femoral condyles. At birth, the healthy infant is born with about 40 degrees of femoral
torsion. By age 16 this angle decreases due to bone growth, muscular activity, and weight bearing. Typically, the
femoral head sits 15 degrees anterior to the mediolateral axis, running through the femoral condyles. This is
known as normal anteversion. Any rotation greater than 15 degrees
anterior to the mediolateral axis is described as excessive
anteversion, and is associated with in toeing at the foot.
Conversely, an femoral torsion less than 15 degrees is described as
retroversion and is associated with toe-out at the foot.
Measurements at the acetabulum should also be noted. There are
two commonly used measurements to describe the extent to which the acetabulum covers and secures the femoral
head: center-edge angle and acetabular anteversion angle. The center-edge angle describes the position of the
acetabulum and the amount of coverage it provides over the femoral head. A normal center-edge angle is
approximately 35 degrees. Any significant decrease in this angle will decrease the coverage of the femoral head,
Figure
13
Angle
of
Inclination
Figure
12
Femoral
Torsion
27. Lower Extremity Arthrology Guide 27
and therefore predispose the hip to dislocations. The acetabular anteversion angle measures the extent to which
the acetabulum projects anteriorly in relation to the pelvis. Normally, acetabular anteversion is about 20 degrees.
When a hip demonstrates excessive acetabular anteversion, the anterior portion of the femoral head is exposed.
When the angle is severe, the hip is more prone to dislocation and labral lesions. The open packed position of the
hip joint is in 30 degrees of flexion, 30 degrees of abduction, and slight external rotation. The closed packed
position is with the hip in full extension, combined with slight external rotation and abduction.
The hip also has a variety of ligaments that attach to restrain certain movements and help keep the joint
stable. The primary ligaments of the joint are iliofemoral, pubofemoral, and ischiofemoral ligaments. All three of
these ligaments blend with the joint capsule and are taut in extension. Out of the three, the iliofemoral ligament is
the strongest. In standing posture, the femoral head moves anteriorly and pushes against the iliofemoral ligament.
Iliofemoral ligament is also taut in external rotation. The pubofemoral ligament is taut in hip abduction and
external rotation. The ischiofemoral ligament is the opposite, and is taut in hip adduction and internal rotation.
Knowledge of these ligaments is useful therapeutically during attempts to stretch the entirely of the hip capsule.
With full hip extension, combined with slight internal rotation and abduction, twists most of the ligaments into
their taut position and so this is called closed packed position. The opposite of this position would be to the open
packed position of the hip joint is in 30 degrees of flexion, 30 degrees of abduction, and slight external rotation.
The ligamentum teres and transverse acetabular ligament also stabilize the hip. The ligamentum teres runs from
the head of the femur directly to the acetabular fossa, which helps to maintain the alignment of the femoral head
in the fossa. The transverse acetabular ligament completes the acetabular ring, reinforcing the inferior aspect of
the joint.
Ligaments of the Femoral Acetabular
Ligaments Attachments Function Associated constraints of the joint
Iliofemoral Anterior inferior iliac spine,
intertrochanteric line of the femur
Reinforces the joint capsule Limits extension of the femur
Ischiofemoral Ischium posterior to the acetabulum,
greater trochanter, iliofemoral
ligament
Reinforces the joint Assists iliofemoral ligament in limiting
extension of the femur
Pubofemoral Iliopubic eminence,
superior pubic ramus, fibrous joint
capsule
Reinforces the joint capsule Limits abduction of the femur
28. Lower Extremity Arthrology
28
Ligamentum
teres
Fovea of the femoral head,
acetabular notch
Attaches the femoral head to
the acetabular fossa
Prevents distraction/dislocation of the femoral
head from the acetabulum
Transverse
acetabular
Margins of the acetabular notch Completes the inferior part of
the acetabulum
Resists caudal translation of the femoral head
Common Joint Pathology
Femoroacetabular impingement (FAI). In FAI, bone spurs develop around the femoral head and/or
along the acetabulum. The bone overgrowth causes the hipbones to hit against each other rather than to move
smoothly. Over time, this can result in the tearing of the labrum and breakdown of articular cartilage
(osteoarthritis). There are three types of FAI: pincer, cam, and
combined impingement. Pincer type of impingement occurs because
extra bone extends out over the normal rim of the acetabulum. The
labrum can be crushed under the prominent rim of the acetabulum.
Pincer type is more common in females. In cam impingement the
femoral head is not round and cannot rotate smoothly inside the
acetabulum. A bump forms on the edge of the femoral head that grinds the cartilage inside the acetabulum. Cam
impingement is more common in males. Combined impingement occurs when both pincer and cam types are
present, which is common. Impingement is most typically felt in hip flexion, adduction and external rotation.
People with FAI usually have pain in the groin area, although the pain may be lateral to the groin. Patients may
complain of a dull ache or sharp stabbing pain with turning, twisting, and squatting.
Labral tears. FAI, trauma or arthritis can all result in labral tears. Planting the leg on the ground and
twisting usually is a cause of traumatic tears. Major trauma such as motor vehicle accidents can also tear the
labrum. As people develop arthritis; they can also develop labral tears. Patients usually complain of clicking, pain,
feeling of giving out, symptoms get worse with prolonged walking, standing, sitting.
Osteoarthritis. In osteoarthritis, the cartilage in the hip joint gradually
wears away over time. As the cartilage wears away, it becomes frayed and rough
and the protective joint space between the bones decreases. This can result in bone
Figure
14
Hip
FAI
Figure
15
Hip
Osteoarthritis
29. Lower Extremity Arthrology Guide 29
rubbing on bone. To make up for the lost cartilage, the damaged bones may start to grow outward and form bone
spurs (osteophytes). Osteoarthritis develops slowly and the pain worsens over time and is most common in people
over the age of 50, though younger people are affected by it also. The most common symptom of hip
osteoarthritis is pain around the hip joint. Usually pain has a slow onset, but it may have a sudden onset. Pain and
stiffness may be worse in the morning or after sitting for a long period of time. Over time, painful symptoms may
occur more frequently including during rest or at night. Patients with OA can also present with limited range of
motion especially into internal rotation and flexion.
Hip fractures. Fractures are a very serious and common issue in the United States. The most common
mechanisms of injury for hip fractures are falls and collisions. The older population is more affected by this and
unfortunately the incidence may continue to rise due to the increased life expectancy. The patient with a hip
fracture will have pain over the outer upper thigh or in the groin. There will be significant discomfort with any
attempt to flex or rotate the hip. Fractures are usually treated with surgery. The type of surgery used to treat a hip
fracture is primarily based on the bones and soft tissues affected or on the level of the fracture. Approximately
40% of those with a hip fracture are able to perform their daily functioning needs however; about half will
continue to use an assisted device for walking.
30. Lower Extremity Arthrology
30
Knee Joint Complex
Introduction
The knee joint is formed by articulations between the patella, femur and tibia (Figure 16). The knee is the
largest joint and the most frequently injured joint in the body.
The tibiofemoral portion of the knee joint is a hinge type
synovial joint. It is the most complex diarthrosis of the body.
The knee primary motions include flexion and extension with
some external and internal rotation. The knee is overall
mechanically referred to as a weak joint. The stability and
strength of this joint is fully dependent on the strength of the
muscles and tendons surrounding joint entirety, as well as the
ligaments connecting the tibia and the femur.
The knee has up to 14 bursae of various sizes in and around the knee joint complex. Bursae help provide
an extra amount of friction control for the joint to move fluidly. Bursae around the patella include the prepatellar
bursa, the superficial and deep infrapatellar bursae, and the suprapatellar bursa. Bursae of the complex that are not
in close anatomical proximity to the patella include the pes anserine bursa, the iliotibial bursa, the tibial and
fibular collateral ligament bursae and the gastrocnemius-semimembranosus bursa. These fluid filled sacs cushion
the joint and reduce friction between muscles, bones, tendons and ligaments.
The knee is important biomechanically during walking. In the stance phase, the knee is slightly flexed.
This allows shock absorption, energy conservation, and transmission of forces to the lower limb. In swing phase,
the knee is flexed in order to shorten the functional length of the lower limb, which helps the foot clear the
ground. Gait has functional requirements of both stability and mobility for the knee to allow proper energy-
efficient and safe propulsion over ground.
Figure
16
Knee
Joint
Articulations
31. Lower Extremity Arthrology Guide 31
Muscles of the Knee Joint Complex
Muscles Proximal attachment Distal attachment Action Segmental
Innervation
Peripheral
innervation
Sartorius anterior superior iliac
spine
medial aspect of the proximal
tibia
flexes and assists internal
rotation of the knee
(L2-3 [4]) Femoral nerve
Rectus
femoris
anterior inferior iliac spine
and groove superior to the
acetabulum
the base of the patella extends knee (L2-3-4) Femoral nerve
Vastus
intermedius
anterior aspect of the
proximal 2/3rds of the
femoral shaft
lateral border of the patella
actions- extends knee
Extends knee (L2-3-4) Femoral nerve
Vastus
lateralis
Intertrochanteric line,
greater trochanter, gluteal
tuberosity and linea aspera
Base and lateral border of the
patella
Extends knee (L2-3-4) Femoral nerve
Vastus
medialis
Intertrochanteric line,
spiral line, linea aspera
and medial supracondylar
line
Base and medial border of the
patella
Extends knee (L2-3-4) Femoral nerve
Tensor
fasciae latae
ASIS & external lip iliac
crest
iliotibial tract assists in maintaining
knee extension
(L4-5-S1) Superior
gluteal nerve
Gracilis body of the pubis &
inferior pubic ramus
medial surface of tibia, distal
to condyle, proximal
to insertion of semitendinosus,
lateral to insertion of sartorius
flexes & medially rotates
the knee
(L2-3-4) Obturator
nerve
Biceps
femoris
ischial tuberosity &
sacrotuberous lig. (long
head) ; lateral lip of linea
aspera & lateral
supracondylar line (short
head)
lateral side of fibular head Both heads: Flex knee
Long Head: Extends hip
Long head:
(L5-S1-2-3)
Short head:
(L5-S1-2)
Long head:
tibial branch of
sciatic nerve
Short head:
Fibular branch
of sciatic nerve
Semimembr
anosus
Posterior aspect of the
medial tibial condyle
posterior aspect of the medial
tibial condyle
Ischial tuberosity (L4-5-S1-2) Tibial division
of the sciatic
Semitendin
osus
ischial tuberosity proximal, medial tibia flexes & medially rotates
knee
(L4-5-S1-2) Tibial division
of the sciatic
Gastrocnem
ius
posterior aspect of the
condyles and joint capsule
Posterior calcaneal surface flexes knee (S1-2) Tibial nerve
Popliteus lateral femoral condyle
and oblique popliteal
ligament
Soleal line of the tibia In NWB, IR of tibia and
knee flexion; in WB
insertion is fixed:
ER of femur and knee
flexion; unlocks the knee
from extension into early
flexion
(L4-5-S1) Tibial nerve
Articularis
Genu
Distal anterior shaft of
femur
Proximal portion of synovial
membrane of knee joint
Pulls articular capsule
proximally
(L2-3-4) Femoral
32. Lower Extremity Arthrology
32
Tibiofemoral Joint
Overview
The tibiofemoral joint is formed by the condyles of the femur and the tibial plateau. The joint is a
modified hinge joint with two degrees of freedom. The primary motion is flexion and extension in the sagittal
plane. Some internal and external rotation can occur with slight flexion of the knee. The quadriceps femoris is
considered to be the most important muscle for stabilization of the tibiofemoral joint. The knee is considered
most stable in a fully extended position. This is the position where the femur’s contact on the tibia, is most
congruent and the ligaments associated with the tibiofemoral joint are the most taut. In this position, many of the
tendons surrounding the joint act as supporting structures as well.
Neurovasculature. There are 10 vessels that come together to form the periarticular genicular
anastomoses around the knee to supply blood to the knee joint. These 10 vessels include: genicular branches of
the femoral, popliteal, and anterior and posterior recurrent branches of the anterior tibial recurrent and circumflex
fibular arteries. Other supporting features of the tibiofemoral joint including the joint capsule, the cruciate
ligaments, the outer portions of the menisci, and the synovial membrane are supplied by the middle genicular
branches of the popliteal artery. The tibiofemoral is innervated by all the nerves supplying the muscles that cross
the knee joint. Branches from the femoral nerve innervate the anterior aspect of the knee. The tibial nerve supplies
the posterior aspect, and the common fibular nerve innervates the lateral aspect. Articular branches from both the
obturator and saphenous nerves supply the medial aspect of the knee.
Tissue Layers
• Skin
o Epidermis
o Dermis
o Hypodermis
• Superficial fascia (fascia lata)
o Subcutaneous tissue
• Deep fascia
• Muscles and tendons
o Quadriceps femoris
§ Rectus femoris
§ Vastus lateralis
§ Vastus medialis
§ Vastus intermediate
33. Lower Extremity Arthrology Guide 33
o Hamstrings
§ Biceps femoris
§ Semimembranosus
§ Semitendinosus
o Gracilis
o Sartorius
o Gastrocnemius
o Popliteus
o Iliotibial band
• Vascular supply
o Popliteal artery
o Descending genicular
o Anterior tibial recurrent artery
o Posterior tibial recurrent artery
o Circumflex fibular artery
o Inferior medial genicular artery
o Inferior lateral genicular artery
o Middle genicular artery
o Superior medial genicular artery
o Superior lateral genicular artery
• Innervation
o Obturator
o Femoral
o Tibial
o Common fibular
o Saphenous
o Nerve to the popliteus
o Nerve to gastrocnemius
• Ligaments
o Medial collateral ligament
o Lateral collateral ligament
o Oblique popliteal ligament
o Arcuate popliteal ligament
o Coronary ligament
o Transverse ligament of the knee
o Meniscofemoral ligament
• Fibrous joint capsule
o Synovial membrane
o Ligaments
§ Anterior cruciate ligament
§ Posterior cruciate ligament
o Menisci
§ Medial menisci
§ Lateral menisci
o Bursa
§ Prepatellar bursa
§ Suprapatellar bursa
§ Superficial infrapatellar bursa
§ Deep infrapatellar bursa
§ Semimembranosus bursa
§ Pes anserine bursa
34. Lower Extremity Arthrology
34
o Plicae
§ Suprapatellar plica
§ Infrapatellar plica
§ Medial plica
o Fat pads
§ Infrapatellar fad pad
o Synovial fluid
o Articular cartilage
Joint Motions
Motion Primary Movers Secondary Movers Degrees Possible
Knee
flexion
Hamstrings (semitendinosus, semimembranosus,
long head of the biceps); short head of the biceps
Gracilis, sartorius,
gastrocnemius, popliteus
135 degrees
Knee
extension
Quadriceps femoris Weakly: tensor of fascia
lata
0 degrees, hyperextension may be
available up to 10-15 degrees
Knee
external
rotation
Biceps femoris when the knee is in a flexed
position
NA 40 degrees; may be difficult to
establish neutral rotation
Knee
internal
rotation
Semitendinosus and semimembranosus when knee
is flexed; popliteus when non-weight bearing and
with the knee extended
Gracilis, sartorius 30 degrees; may be difficult to
establish neutral rotation
Biomechanics and Joint Configuration
The tibiofemoral joint primary motions are flexion and extension; which occur about the mediolateral axis
of rotation. The range of motion of the knee is 130 to 150 degrees of knee flexion and 5 to 10 degrees of knee
extension beyond neutral position. External and internal rotation of the knee occurs about a longitudinal axis of
rotation. These rotations increase with knee flexion. At 90 degrees of knee flexion, the knee can rotate internally
about 30 degrees and externally at about 45 degrees. Beyond 90 degrees of flexion, rotation decreases due to
limitations by soft tissues.
An important concept, which helps with the stability of the knee, is the screw home mechanism. During
the last portion of active range of motion into extension a rotation between the tibia and the femur occurs. This
rotation produces the screw home mechanism, or “locking” of the knee. The rotation happens during the last 30
degrees of knee extension. Anterior tibial glide persists on the tibia's medial condyle because its articular surface
is longer in that dimension than the lateral condyle. Prolonged anterior glide on the medial side produces external
35. Lower Extremity Arthrology Guide 35
tibial rotation. There are three factors that affect the rotation mechanism; the shape of the medial femoral condyle,
the passive tension of the anterior cruciate ligament, and the lateral pull of the quadriceps muscle. This rotation is
not under voluntary control. This helps the knee’s stability for standing upright. The screw-home mechanism
decreases the work of the quadriceps femoris muscle. The muscle can relax once the knee joint is fully extended.
To unlock the extended knee, the joint internally rotates first. The popliteal muscle rotates the femur externally or
rotates the tibia internally to initiate flexion from a fully extended starting position.
The distal femoral condyles create a convex surface and the proximal tibial plateau creates concave
surface. The tibial condyles slide posteriorly on the femoral condyles during flexion, and slide anteriorly during
extension. In unloaded movement, open chain, the concave surface will glide in the same direction of the rotation.
In loaded movement, closed chain, the convex surface will glide in the opposite direction of the rotation.
The medial meniscus has an oval shape (Figure 17) and it
attaches to the deep layer of the medial collateral ligament and
capsule. The lateral meniscus has circular shape and it attaches only
to adjacent capsule. The quadriceps and semimembranosus attach to
both menisci and the popliteus attaches only to the lateral meniscus.
These muscles help to stabilize the menisci.
Neurovasculature supply of the menisci is greatest at the
external borders, while the internal border has no blood and nerve supply. The menisci are designed to absorb
shock, therefore, they reduce the compressive stress across the joint. During walking the compressive forces at the
joint reach 2.5-3x the body weight and increase to 4x the body weight with stair climbing. The menisci help to
reduce the pressure on the articular cartilage by increasing the contact area, which protects the knee joint. In
addition, it also increases stability of the knee by deepening the tibial plateaus, decreasing friction by 20%, and
increasing contact area by 70%. Increasing the contact area helps to disperse force over a greater surface area, and
decrease the total force experienced by any one point in the joint. The menisci serve a vital role in maintaining the
integrity and functionality of the tibiofemoral joint.
Figure
17
Tibial
Plateau
Anatomy
36. Lower Extremity Arthrology
36
The ligaments that surround the knee are
important in stabilizing the knee. The cruciate
ligaments also guide the knee in natural
arthrokinematics by creating tension, and contribute to
the proprioception of the knee. The anterior cruciate
ligament (ACL) runs from posterior femur to anterior
side of the tibia (Figure 18). Its tension changes as the
knee flexes and extends. The anteromedial bundle is taut in
flexion and the posterolateral bundle is taut in extension. It is mainly taut as the knee reaches to full extension.
The posterior cruciate ligament (PCL) runs from the posterior intercondylar area of the tibia to the lateral side of
the medial femoral condyle (Figure 18). Most fibers of this ligament become taught with increasing knee flexion.
Tension peaks between 90 and 120 degrees of knee flexion. The primary role of the collateral ligaments is to limit
excessive motion of the knee in the frontal plane. The ligaments also play a role in
providing resistance to extreme external and internal rotation of the knee. The
medial collateral ligament (MCL) is a flat, broad ligament (Figure 19). It had two
layers, superficial and deep, the run from the femur to the tibia and the medial
meniscus. The superficial fibers blend with the medial patellar retinaculum fibers.
The deep fibers attach to the posterior-medial joint capsule, medial meniscus, and
tendon of the semimembranosus muscle.
The MCL resists valgus force. Since the
deeper fibers are shorter, they are more commonly injured than the
superficial fibers during excessive valgus trauma. The lateral collateral
ligament (LCL) is a round ligament that runs from the lateral epicondyle
of the femur and the head of the fibula (Figure 20). The LCL does not
attach to the lateral meniscus. It resists varus force.
Figure
18
Ligamentous
Contribution
to
Knee
Figure
19
Medial
Collateral
Ligaments
Figure
20
Lateral
Collateral
Ligament
37. Lower Extremity Arthrology Guide 37
The knee has a crucial role during gait. During heel contact, the knee is in 5 degrees of flexion and it
continues to flex to 15 or 20 degrees during loading response. The quadriceps eccentrically control this flexion.
This helps with weight acceptance as the weight of the body shifts to the lower extremity. After slight flexion, the
knee extends until heel off. The knee then begins to flex again to 35 degrees during toe off. By mid swing knee
flexion reaches a maximum knee flexion of 60 degrees. This knee flexion is to shorten the length of the lower
limb and assist toe clearance. In mid and terminal swing the knee extends again. During gait, the knee requires
range of motion from full knee extension to 60 degrees of knee flexion. Gait impairments are noted when a lack
of knee range is available. A lack of knee flexion and extension will impair toe clearance and functional length.
Ligaments of the Tibiofemoral
Ligament Proximal attachment Distal attachment Function
Anterior cruciate ligament
(ACL)
posterior femur anterior side of the tibia Resist extension
Resist extremes of varus, valgus,
and axial rotation
Posterior cruciate ligament
(PCL)
anteroinferior femur posterior side of the tibia Resist knee flexion
Resist extremes of varus, valgus,
and axial rotation
Lateral collateral Ligament
(LCL)
Femur Fibula resist varus resist knee extension
resist extremes of axial rotation
Medial collateral ligament
(MCL)
Femur
*Two layers (deep and superficial)
Tibia and the medial meniscus Resist valgus
Resist knee extension
Resists extremes of axial rotation
Oblique popliteal ligament Tendon of the Semimembranosus Posterior lateral condyle of the
femur
Stabilizes the posterior aspect of
the knee joint
Limits external rotation of the
tibia
Transverse ligament of the
knee
Anterior edge of menisci crosses anterior intercondylar
area
holds menisci together during
knee movement
Coronary ligament of the
knee
Inferior edges of the medial lateral menisci to the joint
capsule of the knee
limiting rotation of the knee
stabilizes medial and lateral
menisci
Arcuate popliteal ligament Posterior fibular head posterior surface of the knee reinforces posterior lateral joint
capsule
Meniscofemoral ligament:
1. Anterior
2. Posterior
Posterior horn of the lateral meniscus
Extends from the posterior horn of
lateral meniscus
Distal edge of the femoral
PCL
Medial femoral condyle
Stabilizes the lateral meniscus
38. Lower Extremity Arthrology
38
Common Joint Pathology
Knee Fracture. With injury to the knee, it is important to rule out a suspected fracture. There are two
prediction rules for use in determining the need for a radiograph of the knee; the Ottawa Knee Rules, and the
Pittsburgh Knee Rules.
Ottawa Knee Rules
• age 55 or older
• isolated tenderness of the patella
• tenderness over the fibular head
• inability to flex knee >90 degrees
• inability to weight bear immediately, or in the emergency room for 4 steps
Pittsburgh Knee Rules
• Blunt trauma or fall as the mechanism of injury as well as either of the following:
• older than 50 years or younger than 12 years
• inability to walk 4 weight bearing steps in the emergency department
Medial Collateral Ligament Injuries (MCL). The most common mechanism of injury to MCL is a force to
the lateral aspect of the knee, creating a valgus force and placing strain on the MCL. This ligament may also be
injured by a rotational stress at the knee. In order to test for this injury, a valgus stress test can be completed in
both full extension and in 25-30 degrees of knee flexion. If there is laxity in the full extension position, this
indicates a possible sprain of the MCL, the cruciate ligaments, or the medial capsule. If there is laxity in 25-30
degrees of flexion, this indicates an MCL sprain specifically. Most injuries to the MCL can be managed non-
operatively with bracing due to the good blood supply to the MCL.
Lateral Collateral Ligament Injuries (LCL). This ligamentous injury is much less common than injury
to the MCL. The most common mechanism of injury is a force to the medial aspect of the knee, creating a varus
force and placing strain on the LCL. This injury is rarely isolated and may also cause injury to the cruciate
ligaments and knee joint capsule. In order to test for this injury, a varus stress test can be completed in both full
extension and in 25-30 degrees of knee flexion. If there is laxity in knee full extension, it may indicate damage to
39. Lower Extremity Arthrology Guide 39
the LCL, cruciate ligaments, or lateral capsule. If there is laxity of 25-30 degrees of knee flexion, it indicates
specifically an LCL sprain. Apley’s distraction test and the dial test are other tests that can also be completed.
With this injury, it is important to rule out fibular nerve injury due to the close location of the fibular nerve. The
LCL does not have a good blood supply and may need surgical repair.
Anterior Cruciate Ligament Injuries (ACL). Most injuries to the ACL are non-contact rotational forces
to the knee or the knee being put into a position of hyperextension. This may be an isolated injury or other
structures such as the joint capsule, the menisci, or the MCL may also be injured. With injury to the ACL, the
patient may state there was a “pop” or state “my knee gave out”. This injury is often accompanied by immediate
onset of swelling in the knee and is often treated surgically depending on the level of performance of the patient.
An injury to the ACL is more common in women than men due to specific anatomical differences. In order to test
for injury to the ACL, and anterior drawer test and Lachman’s test can be completed in order to look for excess
anterior displacement of the tibia on the femur. A pivot shift test is also used to determine if there is injury to the
ACL. For post-surgical rehabilitation, open chain knee extension is contraindicated.
Posterior Cruciate Ligament Injuries (PCL). The PCL is one of the strongest ligaments in the body.
The most common mechanism of injury to the PCL is hitting the dashboard in a motor vehicle accident or falling
on a bent knee, placing a posterior force on the tibia. This ligament can also be damaged as the result of a
rotational force or hyperextension. Special tests used in order to test for injury to this joint include, posterior
drawer test and the sag sign, looking for posterior displacement of the tibia on the femur. Depending on the
severity of the injury, injury to the PCL may be treated surgically or nonsurgically. For post-surgical
rehabilitation, open chain knee flexion is contraindicated.
Medial and Lateral Meniscus Injuries. The outer ⅓ of the menisci is the only area of the menisci that
has a good blood supply and a good potential to heal without surgery. The middle ⅓ of the menisci may have
healing potential and the inner ⅓ of the menisci has no blood supply and will not heal, requiring surgical
management. The most common mechanism of injury to the menisci is a forced rotation while flexing or
extending the knee. Forced tibia external rotation usually results in injury to the medial meniscus, and forced
tibial internal rotation usually results in injury to the lateral meniscus. With a meniscal injury, the patient may
40. Lower Extremity Arthrology
40
complain of a “locking” feeling in the knee and a slower onset of swelling. Four clinical features suggestive of a
meniscal injury include: joint line tenderness, mild to moderate effusion that occurs over 1-2 days, positive
McMurray’s, Apley’s, Thessaly’s test, or functional squat, and quadriceps atrophy over the first week or two
following the injury.
Patellofemoral Joint
Overview
The patellofemoral joint is between the articular side of the patella and the intercondylar groove of the
femur. This joint is arthrodial (plane), non-axial, multiplanar. The movement of the joint is dictated by the
trochlear groove. The patellofemoral joint slides superiorly when the knee extends and inferiorly when the knee
flexes. A slight amount of medial and lateral deviation, as well as tilting, takes place during normal movement.
The joint is stabilized by the forces produced by the quadriceps muscle, the fit of the joint surfaces, and passive
restraint from the surrounding retinacular fibers and capsule.
The patella is the largest sesamoid bone in the body. The patella is attached to the tibial tuberosity by the
patellar tendon and is buried within the quadriceps tendon superiorly. Two facets exist on the posterior articular
surface of the patella (Figure 21). The lateral facet is larger and slightly concave and it moves along the lateral
condyle of the femur. The medial facet has different variations. It moves along the medial condyle of the femur.
Most patellae also have an odd facet, which is a
second vertical ridge between the medial border
that separates the medial facet from an extreme
medial edge. An important stabilizer of the
patella is the vastus medialis obliquus muscle,
which helps with the patella alignment.
Neurovasculature. The circulatory blood supply to the patella is made up of branches of six main
arteries: the descending genicular, the superior medial and lateral genicular, the inferior medial and lateral
genicular, and the anterior genicular. These branches anastomose, forming the prepatellar arterial network and,
Figure
21
Patellar
Anatomy
41. Lower Extremity Arthrology Guide 41
with the transverse infrapatellar artery, form the extraosseous patellar supply. Other smaller arteries originating
from the popliteal and quadriceps arteries supply the patella entering at the base and the lateral sides. The
infrapatellar branch of the saphenous nerve innervates the anterior aspect of the knee, which is a sensory nerve.
Tissue Layers
• Skin
o Epidermis
o Dermis
o Hypodermis
• Superficial fascia- fascia lata
o Subcutaneous tissue
• Deep fascia
• Muscles and tendons
o Quadriceps tendon
• Arterial supply
o Descending genicular artery
o superior medial genicular artery
o lateral genicular artery
o Inferior medial genicular artery
o Anterior genicular artery
o Popliteal artery
• Innervation
o Saphenous nerve
o Posterior tibial nerve
o Obturator nerve
o Femoral nerve
• Ligaments
o Patellar ligament
• Fibrous joint capsule
o Synovial membrane
o Ligaments
§ Medial patellofemoral ligament
§ Lateral patellofemoral ligament
§ Medial patellar retinaculum
§ Lateral patellar retinaculum
§ Iliotibial tract
o Bursa
§ prepatellar bursa
§ suprapatellar bursa
§ superficial infrapatellar bursa
§ deep infrapatellar bursa
o Plicae
§ suprapatellar plica
§ infrapatellar plica
§ medial plica
o Fat pads