There are three types of joints: synarthrosis (immovable), diarthrosis (movable), and amphiarthrosis (slightly movable). Joints can also be classified structurally as fibrous, cartilaginous, or synovial. Fibrous joints include sutures, syndesmoses, and interosseous membranes. Cartilaginous joints include synchondroses, symphyses, and epiphyseal cartilage. Synovial joints contain articular cartilage, a joint cavity filled with synovial fluid, an articular capsule, and a synovial membrane that secretes fluid. There are six classes of synovial joints distinguished by their motion:

1. 1
Arthrology
2/18/2021
Ashete Adere (MSc in Medical Anatomy)

2. Joints are sites where two skeletal
elements came together
When skeletal elements separated by
a cavity-Synovial joints
When there is no cavity and skeletal
elements separated by connective
tissue-solid joints
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Ashete Adere (MSc in Medical Anatomy)

3. Functional classification of joints
Synarthrosis-immovable joint
Diarthrosis-movable
Amphiarthrosis-slightly movable
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4. Structural classification
 Fibrous joints
 Articulating bones are united by thin layer of
dense irregular connective tissue
 Three types of fibrous joints
 Sutures-immovable-only between bones of
the skull
 Syndesmosis- slightly movable-distal
tibiofibular and gomphosis(dento-alveloral
joint
 Interosseous membrane- slightly movable-
between radius and ulna,tibia and fibula 2/18/2021
Ashete Adere (MSc in Medical Anatomy)

5. 2/18/2021
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6. Cartilaginous joints
 Three types of cartilaginous joints
 Synchondrosis
 Slightly movable
• Connecting material is hyaline cartilage. First rib an manubrium of
the sternum
 Symphysis
 Slightly movable
• End of articulating bones are covered by fibrocartilage
e.g symphysis pubis, intervertebral joint, b/n manubrium and body
of the sternum
 Epiphyseal cartilage
 immovable
• Growth centers during endochondral bone formation
• Immovable type
• E.g Epiphyseal plate that connects diaphysis and epiphysis of
growing bone
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Ashete Adere (MSc in Medical Anatomy)

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8. Synovial joints
 Facing two surfaces of bones are covered
with articular cartilage
 Separated by joint cavity containing
synovial fluid
 Articular capsule-encloses cavity and
contain fluid
 Synovial membrane- secrete fluid that
contains macrophage-remove debris
2/18/2021
Ashete Adere (MSc in Medical Anatomy)

9. 2/18/2021
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10. Classes of synovial joints
 Distinguished by patterns of motion and
shape of articulating surface
1. Ball and socket joints
Multi-axial
Smooth spherical head of one bone
fits into cup like depression of other
E.g shoulder and hip joints
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12. 2.Condyloid joints
Biaxial diarthrosis
Oval convex surface one bone
articulate with elliptical depression of
other
E.g radiocarpal and
metacarpophalangeal joint
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Ashete Adere (MSc in Medical Anatomy)

13. 3.Saddle joint
Each bone surface is saddle shaped
biaxial
Concave on one axis and concave on
perpendicular axis
Trapezio-metacarpal and
sternoclavicular joints
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14. 4.Plane /gliding joint
 Biaxial diarthosis
 Slightly concave/convex surface sliding
across each other
 E.g intercarpal and intertarsal joint, joints
between articular process of vertebra
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Ashete Adere (MSc in Medical Anatomy)

15. 5. Pivot joints
Monoaxial
Bone spins on its longitudinal axis
During pronation and supination
,disclike radial head spins over its axle
Projection of one bone fits into
ringlike ligaments of another
E.g atlantoaxial joint and proximal
radioulnar joint
2/18/2021
Ashete Adere (MSc in Medical Anatomy)

16. 6.Hinge joints
Monoaxial
Able to flex and extend in only one
plane
E.g elbow, knee,and interphalangeal
joints
2/18/2021
Ashete Adere (MSc in Medical Anatomy)