Synovial joint
Synovial joint found between bones by synovial cavity (joint cavity) containing synovial fluid.
Free movable
End of bones covered by smooth hyaline cartilage, lubricated by thick fluid called synovial fluid and joint is enclosed by flexible articular capsule.
Synovial joints
1. Shoulder (Glenohumeral) joint ; ball and socket synovial joint
2. Wrist joint; condylar Joint
3. Radioulnar joint
4. Hip joint/ coxal joint; ball and socket
5. Elbow joint; Hinge joint
6. Knee (tibiofemoral) joint
7. Ankle joint ; Hinge joint
Structure of synovial joints
1. Synovial cavity or joint cavity
Contains pad of fat.
2. Articular cartilage (shock absorbers)
3. Articular capsule
a. Fibrous capsule (movement of joint)
b. Synovial membrane; combined with articular cartilage
(surround synovial cavity, secrete lubricating synovial fluid into cavity that lubricates it.
4. Synovial fluid
Contain phagocytic cells.
Hyaluronic acid
Secreted by synovial membrane fills synovial cavity (lubricating)
5. Articular disc or fibrocartilaginous discs
Shock absorbers
Prevent clashing between bones.
Fit surface of bones together.
Maintain stability of joint.
Types of Synovial Joint
According to shape of adjoining articular surface;
1. Plain/ Gliding
2. Hinge
3. Pivot
4. Condylar ellipsoidal
5. Saddle
6. Ball and socket
1. Plain/ Gliding
Multiaxial joint.
Form between two bones in which articular, or free, surfaces of the bones are flat, enabling bones slide over each other.
For example; intervertebral disc, intercarpal joint
2. Hinge
Uniaxial joint
Bone joint in which articular surfaces are molded to each other in such manner as to permit motion only in one place.
For example; Elbow, knee
3. Pivot
Trochoid
Uniaxial joint
Rotary joint
Bone joint in which articular surface of bone, freely movable. That allow only rotary movement around single axis.
(Composed of rounded or pointed surface of one bone and ring formed by another one.
For example; top of neck (atlas and axis bone)
4. Condylar ellipsoidal
Biaxial joint
Condylar joint is when oval shaped condyle of one bone fits into an elliptical cavity of another one.
For example; wrist joint (radiocarpal joint)
Metacarpophalangeal joints
5. Saddle
Biaxial joint
For example; Carpometa carpal joint at base of thumb.
For example; sterno clavicular joint of chest.
Providing more flexibility than hinge or gliding joint.
6. Ball and socket
Multiaxial joint
Wide range of motion
Joint one rounded surface of (ball) that fits into depression or socket in another bone.
For example; Hip joint, shoulder joint
Movement of Synovial joint.
1. Gliding
2. Angular
3. Circulation
4. Special
1. Gliding
Nearly flat bone surfaces ide or glide over each other.
For example; intercarpal joint
Intervertebral discs
2. Angular
Movement produce when angle between bones of a joint change.
1. Flexion
2. Extension
3. Hyper extension
4. Abduction
5. Adduction
6. Dorsiflexion
7. Plantar flexion
3. Circulation
Rotation around axis joint.
1. Circumduction distal and of bones moves in circular motion which proximal end remains stable, achieved by successive flexion, abduction, extension and adduction.
2. Rotation
1. Internal (medial) rotation
Rotates towards midline of body.
2. External (lateral) rotation
Rotates away form midline of body.
3. Pronation
4. Supination
4. Special
1. Inversion
2. Eversion
3. Protraction
4. Retraction
5. Depression
6. Depression
7. Elevation
8. Lateral excursion
9. Apposition
10. Reposition
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