This document provides an overview of muscles and joints in the human body. It discusses the basic parts and types of muscles, including skeletal, cardiac and smooth muscles. It also describes the different components of muscles like origin, fleshy belly, and tendon. Additionally, it covers the classification and types of joints, including fibrous, cartilaginous and synovial joints. Specifically, it details the seven types of synovial joints like hinge, pivot, ball and socket joints. The document aims to introduce students to the key structures and functions of muscles and joints in the musculoskeletal system.

1. Introduction to Medical
Terminologies
Lecture # 2
PREPARED BY
MUHAMMAD SALMAN BUTT
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2. Lecture: 2
o Basic functions of Muscles
oWhat are the different types of muscles.
oWhat are the different parts of muscles.
oWhat are the different components attached with muscles.
oWhat are fascia and its types.
oWhat are joints and its different types present in the human body
oWhat are the structure of various types of joints presents in human body.
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3. Chapter 4: The Muscle
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4. Introduction to Muscles
oThe scientific study of muscles is known as myology.
oThe word muscle is derived from Latin word “Mus”
meaning mouse. Most of muscles of humans resemble a
mouse in their external appearance, the tail of the
mouse representing the tendon of the muscle.
oThe bones, muscles, and joints together form an
integrated system called the musculoskeletal system.
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5. Parts of a skeletal muscles
oOrigin: It is the proximal attachment, which usually remains
fixed during contraction of the muscles.
oFleshy Belly: A muscle may be completely or partly fleshy
throughout its entire length. It consists of skeletal muscle cells.
oTendon: It is the rounded fibrous end of a skeletal muscle.
oAponeurosis: It is a fibrous and membranous part of a muscle
by which it is attached to distant parts, e.g. Bicipital aponeurosis
of biceps brachii muscle.
oInsertion: It is the distal moveable end of a skeletal muscle
which moves during contraction.
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6. Types of Muscular Tissues
Depending upon the microscopic structure of muscle cells, the muscles are classified into three
types
1- Striated or Skeletal muscles: Most skeletal muscle tissue is attached to bones and moves
parts of the skeleton. It is striated; that is, striations, or alternating light and dark protein bands,
are visible under a microscope.
2- Cardiac Muscles: Found only in the heart, forms the bulk of the heart wall. The heart pumps
blood through blood vessels to all parts of the body. Like skeletal muscle tissue, cardiac muscle
tissue is striated. However, unlike skeletal muscle tissue, it is involuntary.
3- Smooth Muscles: Smooth muscle tissue is located in the walls of hollow internal structures,
such as blood vessels, airways, the stomach, and the intestines. It participates in internal
processes such as digestion and the regulation of blood pressure. Smooth muscle is nonstriated
(lacks striations) and involuntary (not under conscious control).
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Summary of the Principal Features of Muscular Tissue
CHARACTERISTICS SKELETAL MUSCLE CARDIAC MUSCLE SMOOTH MUSCLE
Cell Appearance and Features
Long cylindrical fiber with
many peripherally located
nuclei; striated; unbranched
Branched cylindrical fiber,
usually with one centrally
located nucleus intercalated
discs join neighboring fibers;
striated
Fiber is thickest in the middle
tapered at each end, has one
centrally located nucleus; not
striated
Location
Primarily attached to bones
by tendons
Heart
Walls of hollow viscera,
airways, blood vessels, iris and
ciliary body of the eye,
arrector pili of hair follicles
Fiber Diameter Very large (10–100 m)* Large (10–20 m) Small (3–8 m)
Fiber Length Very large (100 m–30 cm) Small (50–100 m) Intermediate (30–200 m)
Speed of Contraction Fast Moderate Slow
Nervous Control Voluntary Involuntary Involuntary

8. Group Action of Muscles
The skeletal muscles are classified into following subgroups depending upon their simple role
during movements at a joint.
1. Prime movers (Agonists): These are those muscles which are constantly active in the
initiation and maintenance of a particular movement. E.g. Biceps is a prime mover of elbow
joint during flexion.
2. Antagonists: These are those muscles which undergo relaxation when the prime mover start
contracting; then they remain silent and finally again contract in order to restrict the range of
mobility. E.g. Triceps brachii is an antagonist during flexion at the elbow.
3. Fixators: stabilizing the origin of the prime mover so that the prime mover can act more
efficiently.
4. Synergists: Most movements also involve muscles called synergists which help the prime
mover function more efficiently by reducing unnecessary movement.
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9. Functions of Muscle
1. They take part in locomotion (movement) .
2. They maintain the posture and stability.
3. They conserve the internal heat of the body.
4. Sorrow and grief is expressed by contraction of muscle of face.
5. Storing and moving substances with the body e.g. Temporary storage of the food in the
stomach or urine in the urinary bladder.
Sphincters: Storage is accomplished by sustained contractions of ring like bands of
smooth muscle called sphincter.
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10. Chapter 05 Structures related to the muscles
A- Fascia: These are fibro-areolar membranous sheets of variable thickness and strength
found in all regions of the body investing the softer and more delicate structures.
Types of fascia: 1- Superficial fascia 2- Deep Fascia
1- Superficial Fascia: It is a membranous sheet consisting of fibro-areolar tissue the meshes
of which are filled with fatty or adipose tissue.
2- Deep Fascia: It is a dense elastic membrane forming covering for the muscles and in some
cases affording for them blind surfaces for attachments. It is devoid of fat cells and is usually
tough and inelastic.
B- Synovial Bursae: These are sac like structures lined by synovial membrane and contain
synovial fluid. They develop at those places where friction is liable to occur during sliding of
tendon.
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11. Characteristics Used to Name Skeletal Muscles
NAME MEANING EXAMPLE
Direction: Orientation of muscle fibers relative to the body’s midline
Rectus Parallel to midline Rectus abdominis
Transverse Perpendicular to midline Transverse abdominis
Oblique Diagonal to midline External oblique
Size: Relative size of the muscle
Maximus Largest Gluteus maximus
Minimus Smallest Gluteus minimus
Longus Longest Adductor longus
Latissimus Widest Latissimus dorsi
Longissimus Longest Longissimus muscles
Magnus Large Adductor magnus
Major Larger Pectoralis major
Minor Smaller Pectoralis minor
Vastus Great Vastus lateralis
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NAME MEANING EXAMPLE
Action: Principal action of the muscle
Flexor Decreases joint angle Flexor carpi radialis
Extensor Increases joint angle Extensor carpi ulnaris
Abductor Moves bone away from midline Abductor pollicis longus
Adductor Moves bone closer to midline Adductor longus
Levator Produces superior movement Levator scapulae
Depressor Produces inferior movement Depressor labii inferioris
Supinator Turns palm anteriorly Supinator
Pronator Turns palm posteriorly Pronator teres
Sphincter Decreases size of opening External anal sphincter
Tensor Makes a body part rigid Tensor fasciae latae
Number of Origins: Number of tendons of origin
Biceps Two origins Biceps brachii
Triceps Three origins Triceps brachii
Quadriceps Four origins Quadriceps femoris

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14. Lecture Link
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Important link
Hear the illustration http://edugen.wileyplus.com/edugen/lti/main.uni

15. Chapter 06: The joints
Joints: A joint (also called an articulation) is a
point of contact between bones, between
cartilage and bones, or between teeth and
bones. When we say one bone articulates with
another bone, we mean that the two bones
form a joint.
Arthrology: is the scientific study of joints
Kinesiology: The study of motion of the
human body is called kinesiology
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Knee Joint

16. Classification of Joints
The structural classification of joints is based on two criteria:
i. The presence or absence of a space between the articulating bones, called a synovial cavity.
ii. The type of connective tissue that holds the bones together.
Structurally, joints are classified as one of the following types:
1. Fibrous Joint: There is no synovial cavity and the bones are held together by dense irregular
connective tissue that is rich in collagen fibers.
2. Cartilaginous joints: There is no synovial cavity and the bones are held together by cartilage.
3. Synovial joints: The bones forming the joint have a synovial cavity and are united by the
dense irregular connective tissue of an articular capsule, and often by accessory ligaments.
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17. Functional Classification of Joints
The functional classification of joints relates to the degree of movement they permit.
Functionally, joints are classified as one of the following types:
1. Synarthrosis: An immovable joint. The plural is synarthroses.
2. Amphiarthrosis: A slightly movable joint. The plural is amphiarthroses.
3. Diarthrosis: A freely movable joint. The plural is diarthroses. All diarthroses are synovial
joints. They have a variety of shapes and permit several different types of movements.
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18. Types of Fibrous Joints
Fibrous joints permit little or no movement. The three types of fibrous joints are
(1) sutures, (2) syndesmoses, and (3) interosseous membranes.
1- Suture: is a fibrous joint composed of a thin layer of dense irregular connective tissue. Sutures
unite the bones of the skull. An example is the coronal suture between the frontal and parietal bones.
2- Syndesmosis: is a fibrous joint in which there is a greater distance between the articulating
surfaces and more dense irregular connective tissue than in a suture. The dense irregular connective
tissue is typically arranged as a bundle (ligament) and the joint permits limited movement. One
example of a syndesmosis is the distal tibiofibular joint, where the anterior tibiofibular ligament
connects the tibia and fibula.
3- Interosseous membranes: a substantial sheet of dense irregular connective tissue that binds
neighboring long bones and permits slight movement (amphiarthrosis). There are two principal
interosseous membrane joints in the human body. One occurs between the radius and ulna in the
forearm and the other occurs between the tibia and fibula in the leg
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19. Types of Cartilaginous Joints
Like a fibrous joint, a cartilaginous joint allows
little or no movement. There are two types of
cartilaginous joints;
1- Synchondrosis is a cartilaginous joint in which
the connecting material is hyaline cartilage. An
example of a synchondrosis is the epiphyseal
(growth) plate that connects the epiphysis and
diaphysis of an elongating bone.
2- Symphysis: is a cartilaginous joint in which
the ends of the articulating bones are covered
with hyaline cartilage, but the bones are
connected by a broad, flat disc of fibrocartilage.
The pubic symphysis between the anterior
surfaces of the hip bones is one example of a
symphysis.
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20. Characteristics of Synovial Joints
Synovial joints have certain characteristics that distinguish them from other joints. The unique
characteristic of a synovial joint is the presence of a space called a synovial ( joint) cavity between the
articulating bones. Synovial joints have the following characteristics;
1. The bony articular surface are covered by articular cartilage and not attached to each other.
2. The bony articular surfaces are connected with each other by tubular fibrous capsule (Articular
capsule).
3. The fibrous capsule is lined by mesothelial membrane called synovial membrane. This membrane
does not cover the articular cartilage covering the articular bony ends.
4. Between the articular bones a specific joint cavity is present which is lined by synovial membrane.
The joint cavity is filled with fluid secreted by synovial membrane.
5. The joint capsule in strengthened by the presence of accessory ligament.
6. The joint cavity may be divided partially or completely by an articular disc composed of white fibro
cartilage.
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Knee Joint

22. Types of synovial joint
According to the structural classification the synovial joint can be divided into 7 varieties
1. Plane joints: These are formed by the opposition of fairly flat articular surfaces e.g. Intermetatarsal joint
2. Hinge Joints: They roughly resemble the hinge of a door where the articulating surface are so molded
that they restrict the to and fro movement to one plane. The sides of the joint are typically provided
with strong collateral ligaments, e.g. Elbow joint, Interphalangeal joints.
3. Pivot Joint: These are uni axial joints. They are composed of pivot surrounded by an osteoligamentous
ring. Movement is restricted to a rotation around a longitudinal axis passing through the centre of the
pivot. E.g. Atlanto Axial Joint.
4. Condylar or condyloid Joints: Here two condyles are received into two concave cavities. It allows
principal movement occurring in one plane. E.g. Knee joint.
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5. Ellipsoid Joint: These are biaxial joints formed by reception of an oval convex surface into an elliptical
concavity. E.g. Radiocarpal joint.
6. Saddle Joint: These are biaxial joint which are formed by reception of cancavo convex opposing
surfaces. E.g. Ankle joint.
7. Ball and socket joint: They are poly axial joint and are formed by reception of globular head into a
cup like concavity or socket. E.g. Shoulder and Hip Joint.

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