1. KKU_Biomech_M1_L2
Musculoskeletal system
Lesson (2)
Dr / Shimaa Essa
Lecturer of physical therapy , faculty of community,
King Khalid university

2. Upon successful completion of this lesson you
would be able to:
1- Define joint.
2- Identify functions of Joints.
3- Distinguish between different Classifications
of joints.
4- Identify degrees of freedom for different
joints in human body.

3. • Joint is the meeting of two bones or more in the
skeletal
System.
• Or, it is the connection (or articulation) in the skeleton
between any of its rigid component parts, whether
bones or cartilages.
Arthrology:
• 1- Arthr: means joint or articulation.
• 2- Ology: means the science which deal with.
• Arthrology is the branch of anatomy concerned
with the joints. SO......... Arthrology is the
science of studying joints.

4. What are joints?
A joint, or articulation, is the place where two bones come
together.
How are joints classified?
1- Functional Classification
*focuses on the amount of movement allowed.
Immovable, slightly movable, freely movable.
2- Structural Classification
*focuses on the material that binds the joint together.
a) Fibrous joints-- Immovable
b) Cartilaginous joints-- slightly movable
c) Synovial joints-- freely movable

6.  Fibrous= (Synarthrosis) & (Synostoses) Immovable:
connect bones, no movement. (skull and pelvis).
 Cartilaginous= (Amphiarthrosis) slightly movable,
bones are attached by cartilage, a little movement
(spine or rib’s cartilage).
 Synovial= (Diarthrosis) freely movable, much more
movement than cartilaginous joints. Cavities
between bones are filled with synovial fluid. This
fluid helps lubricate and protect the bones.

7. What are fibrous joints?
• Collagen fibers join
bones
– No joint cavity; made
of fibrous CT
– Usually synarthrotic
• Types
– Sutures: skull (become
bone in middle age)
– Gomphoses: teeth
(periodontal ligament
holds tooth in place)
– Syndesmoses: short
ligaments bind two
bones
• Radius and ulna;
tibia and fibula

8. What are bony joints?
• Synostoses
• Two bones, once separate, now fused
– Frontal bone, Epiphyseal line

9. What are cartilagenous joints?
• Cartilage binds two bones
– No joint cavity
– Usually amphiarthrotic
• Types
– Synchrondroses:
hyaline cartilage
joins
 Epiphyseal plate,
costal cartilage (to
sternum)
– Symphyses:
fibrocartilage joins
 Pubic symphysis,
intervertebral joints

10. What are synovial joints?
o Has joint cavity
between two bones
o Synovial fluid fills
the space
o Always diarthrotic
e.g. Shoulder, knee,
elbow, hip

11. What are the components s of a synovial joint?
• Basic features
1) Joint (articular)
cavity: contains
slippery fluid
- Articular capsule and
cartilage bind cavity
2) Two capsule layers
o Outer fibrous CT capsule,
continuous w/periosteum
o Inner synovial membrane:
CT which secretes fluid

12. What are the components s of a synovial joint?
3) Meniscus: is a pad of
cartilage
- Continuous with synovial
membrane: Shock
absorber
4) Tendon: is a dense,
regular Connective
Tissue
- Attaches muscle to bone
5) Ligament: is a dense,
regular Connective
Tissue
- Attaches bone to bone

13. What types of synovial joints are there?
• Classified as mono-, bi- and multiaxial joints

14. What types of synovial joints based on shape are
there?
flat or slightly curved articular
surface
– Carpals

15. What types of synovial joints based on shape are
there?
most moveable type
– Shoulder and Hip joints (multiaxial)

16. What types of synovial joints based on shape are
there?
Uniaxial (flexion & extension)
– Elbow, knee, finger/toe

17. What types of synovial joints based on shape are
there?
Monoaxial (Rotation)
- Atlas-axis (say no); radioulnar

18. What types of synovial joints based on shape are
there?
concave/convex
surfaces
– Biaxial; only one joint at the
base of thumb
(1st Carpometacarpal joint)

19. What types of synovial joints based on shape are
there?
rounded articular
surface (modified ball & socet),
Biaxial.
– Metacarpophalangeal joints (base of
fingers)

20. What types of synovial joints based on shape are
there?
is an ovoid shaped joint allows (flexion,
extension; abduction, adduction) movement and is
biaxial.
 The Radiocarpal articulation (wrist joint)

21. What types of synovial joints based on shape are
there?
composed of two types of
joints, multiaxial.
 Tempromandibular joint ( Hing + Gliding), it makes (flexion.
extension, protrusion, retrusion, and side way movements)

22. Types of synovial joints based on shape
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

23. Types of synovial joints based on shape
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

24. Summary of
Joint Classes

25. Structural Characteristics Types Mobility
Bones united by 1.Suture 1.Immobile
collagen fibers 2.Syndesmosis (synarthrosis)
3.gomphosis 2.Slightly moveable
(amphiarthrosis)
3.Immobile
Bone ends united 1.Synchondrosi 1.Immobile
by cartilage s (hyaline) 2.Slightly moveable
2.Symphysis
(fibrocartliage)
Bone ends covered 1.Gliding/ Plane Freely moveable
with articular 2.Hinge (diarthrosis) which
cartilage and 3.Pivot depends on joint
enclosed within a 4.Condyloid design
capsule lined with 5.Saddle
a synovial 6.Ball and
membrane socket
7.Ellipsoid
8.Compound