This document provides an overview of the musculoskeletal system, including approaches to studying anatomy, muscle tissue, the skeletal system, joints, and types of synovial joints. It discusses regional, surface, and systemic anatomy approaches. The musculoskeletal system consists of muscle tissue and the muscular system, as well as bone and cartilage that make up the skeletal system. There are three types of muscle tissue and various bone markings and formations are described. Finally, the document outlines the main types of joints and synovial joints based on shape.

1. OJORA K .A
OVERVIEW OF THE
MUSCULOSKELETAL SYSTEM

2. APPROACHES TO STUDYING
ANATOMY
2
 Regional anatomy (topographical anatomy) is the
method of studying the body’s structure by focusing
attention on a specific part consisting of the head, neck,
and trunk (subdivided into thorax, abdomen, back, and
pelvis/perineum), and paired upper limbs and lower
limbs.
 Surface anatomy is an essential part of the study of
regional anatomy.
 It provides knowledge of what lies under the skin and
what structures are perceptible to touch (palpable) in
the living body at rest and in action.

3. Systemic Anatomy
3
 Systemic anatomy is the study of the body’s organ systems
that work together to carry out complex functions.
 The basic systems and the field of study or treatment of each
are:
 The integumentary system (dermatology)
 The skeletal system (osteology)
 The articular system (arthrology)
 The muscular system (myology)
 The nervous system (neurology)
 The circulatory system (angiology)
 The alimentary or digestive system (gastroenterology)
 The respiratory system (pulmonology)
 The genital (reproductive) system (gynecology for females;
andrology for males)
 The endocrine system (endocrinology)

4. Clinical Anatomy
4
 Clinical (applied) anatomy emphasizes aspects of bodily
structure and function important in the practice of
medicine, dentistry, and the allied health sciences.
 It incorporates the regional and systemic approaches to
studying anatomy and stresses clinical application.
 Clinical anatomy often involves inverting or reversing
the thought process typically followed when studying
regional or systemic anatomy.
 For example, instead of thinking, “The action of this
muscle is to . . . ,” clinical anatomy asks, “How would the
absence of this muscle’s activity be manifest?”
 Instead of noting, “The . . . nerve provides innervation to
this area of skin,” clinical anatomy asks, “Numbness in
this area indicates a lesion of which nerve?

5. Musculoskeletal System

6. Introduction
 The Musculoskeletal
system is made up of
two different systems.
 It is important to know
how each system
works.

7. MUSCLE TISSUE AND THE MUSCULAR
SYSTEM
 The muscular system consists of all the muscles of the
body.
 Types of Muscle (Muscle Tissue)
 Muscle cells, often called muscle fibers because they are
long and narrow when relaxed, are specialized contractile
cells.
 Three types of muscle are described based on distinct
characteristics relating to:
 Whether it is normally willfully controlled (voluntary vs.
involuntary).
 Whether it appears striped or unstriped when viewed
under a microscope (striated vs. smooth or unstriated).
 Whether it is located in the body wall (soma) and limbs or
makes up the hollow organs (viscera) of the body cavities

8. Three Types of Muscles
1. Skeletal striated muscle is voluntary somatic muscle that
makes up the gross skeletal muscles.
2. Cardiac striated muscle is involuntary visceral muscle that
forms most of the walls of the heart and adjacent parts of
the great vessels, such as the aorta, and pumps blood.
3. Smooth muscle (unstriated muscle) is involuntary visceral
muscle that forms part of the walls of most vessels and
hollow organs (viscera), moving substances through them
peristaltic contractions.

9. Naming of Muscles
 Muscles may be described or classified according to their
shape, for which a muscle may also be named:
 Flat muscles have parallel fibers often with an
aponeurosis— for example, the external oblique (broad
flat muscle). The sartorius is a narrow flat muscle with
parallel fibers.
 Pennate muscles are feather-like (L. pennatus, feather)
in the arrangement of their fascicles, and may be
unipennate, bipennate, or multi-pennate—for example,
the extensor digitorum longus (unipennate), the rectus
femoris (bipennate), and deltoid (multi-pennate).
 Fusiform muscles are spindle shaped with a round,
thick belly (or bellies) and tapered ends—for example,
biceps brachii.

11. Naming of Muscles
 Quadrate muscles have four equal sides (L. quadratus,
square)—for example, the rectus abdominis, between its
tendinous intersections.
 Circular or sphincteral muscles surround a body
opening or orifice, constricting it when contracted—for
example, orbicularis oculi (closes the eyelids).
 Multi-headed or multi-bellied muscles have more than
one head of attachment or more than one contractile
belly, respectively.

12. Skeletal System
 Its 206 bones form a
rigid framework to
which the softer tissues
and organs of the body
are attached.
 Vital organs are
protected by the
skeletal system.
 They also function to
move, support, produce
red and white blood
cells and store
minerals.

13. The parts of the skeleton
 The human skeleton is
divided into two
distinct parts:
 Axial
 Appendicular

14. Axial Skeleton
 The axial skeleton consists of the bones of the
head (cranium or skull), neck (hyoid bone and
cervical vertebrae), and trunk (ribs, sternum,
vertebrae, and sacrum).

15. Appendicular Skeleton
 The appendicular skeleton is composed of bones that
anchor the appendages to the axial skeleton.
 The Upper Extremities
 The Lower Extremities
 The Shoulder Girdle
 The Pelvic Girdle--(the sacrum and coccyx are
considered part of the vertebral column)

16. The Axial Skeleton
Slide
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Figure 5.6

17. Cartilage and Bones
 The skeleton is composed of cartilages and bones.
 Cartilage is a resilient, semirigid form of connective
tissue that forms parts of the skeleton where more
flexibility is required—for example, where the costal
cartilages attach the ribs to the Sternum and also , the
articulating surfaces of bones participating in joints.

18.  Bone, a living tissue, is a highly specialized, hard form
of connective tissue that makes up most of the
skeleton.
 Bones of the adult skeleton provide:
1. support for the body and its vital cavities; it is the chief
supporting tissue of the body.
2. protection for vital structures (e.g., the heart).
3. the mechanical basis for movement (leverage).
4. storage for salts (e.g., calcium).
5. a continuous supply of new blood cells (produced by
the marrow in the medullary cavity of many bones).

19. CLASSIFICATION OF BONES
 Bones are classified according to their shape.
 Long bones are tubular (e.g., the humerus in the arm).
 Short bones are cuboidal and are found only in the tarsus
(ankle) and carpus (wrist).
 Flat bones usually serve protective functions (e.g., the flat
bones of the cranium protect the brain).
 Irregular bones have various shapes other than long, short, or
flat (e.g., bones of the face).
 Sesamoid bones (e.g., the patella or knee cap) develop in
certain tendons and are found where tendons cross the ends
of long bones in the limbs; they protect the tendons from
excessive wear and often change the angle of the tendons as
they pass to their attachments.

20. Bone Markings and Formations
 Bone markings appear wherever tendons, ligaments,
and fascias are attached or where arteries lie adjacent to
or enter bones.
 Some of the various markings and features of bones are
:
 Capitulum: small, round, articular head (e.g., the
capitulum of the humerus).
 Condyle: rounded, knuckle-like articular area, often
occurring in pairs (e.g., the lateral and medial femoral
condyles).
 Crest: ridge of bone (e.g., the iliac crest).
 Epicondyle: eminence superior to a condyle (e.g., the
lateral epicondyle of the humerus).
 Facet: smooth flat area, usually covered with cartilage,
where a bone articulates with another bone (e.g., the

21. Bone Markings and Formations
 Fossa: hollow or depressed area (e.g., the infraspinous
fossa of the scapula).
 Groove: elongated depression or furrow (e.g., the radial
groove of the humerus).
 Head (L. caput): large, round articular end (e.g., the head
of the humerus).
 Line: linear elevation (e.g., the soleal line of the tibia).
 Malleolus: rounded process (e.g., the lateral malleolus of
the fibula).
 Notch: indentation at the edge of a bone (e.g., the
greater sciatic notch).
 Protuberance: projection of bone (e.g., the external
occipital protuberance).

22. Bone Markings and Formations
 Spinous process: projecting spine-like part (e.g., the
spinous process of a vertebra).
 Trochanter: large blunt elevation (e.g., the greater
trochanter of the femur).
 Trochlea: spool-like articular process or process that acts
as a pulley (e.g., the trochlea of the humerus).
 Tubercle: small raised eminence (e.g., the greater
tubercle of the humerus).
 Tuberosity: large rounded elevation (e.g., the ischial
tuberosity).

23. VASCULATURE AND INNERVATION OF
BONES
 Bones are richly supplied with blood vessels.
 Most apparent are the nutrient arteries (one or more
per bone) that arise as independent branches of
adjacent arteries outside the periosteum and pass
obliquely through the compact bone of the shaft of a
long bone via nutrient foramina.
 Veins accompany arteries through the nutrient foramina.
 Nerves accompany blood vessels supplying bones.

24. Joints
A joint, or articulation, is the place where two
bones come together.
 Fibrous- Immovable:connect bones, no movement.
(skull and pelvis).
 Cartilaginous- slightly movable, bones are
attached by cartilage, a little movement (spine or
ribs).
 Synovial- freely movable, much more movement
than cartilaginous joints. Cavities between bones
are filled with synovial fluid. This fluid helps
lubricate and protect the bones.

25. The Synovial Joint
Slide 5.51
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Figure 5.28

26. Types of Synovial Joints Based on
Shape
Slide
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Figure 5.29a–c

27. Types of Synovial Joints Based on
Shape
Slide
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Figure 5.29d–f

28. Types of Joints
Hinge- A hinge joint allows extension and
retraction of an appendage. (Elbow, Knee)

29. Ball and Socket- A ball and socket joint allows
for radial movement in almost any direction. They
are found in the hips and shoulders. (Hip,
Shoulder)

30. Gliding- In a gliding or plane joint bones slide past
each other. Mid-carpal and mid-tarsal joints are
gliding joints. (Hands, Feet)

31. Saddle- This type of joint occurs when the
touching surfaces of two bones have both
concave and convex regions with the shapes
of the two bones complementing one other
and allowing a wide range of movement.
(Thumb)

32. 32
THE END