Types of Synovial Joints
Let's explore the fascinating world of synovial joints - the most common and movable joints in our body! There are six main types, each designed perfectly for specific movements and functions.
1. Ball and Socket Joint
- Most mobile of all synovial joints
- Consists of a rounded head of one bone fitting into a cup-like socket of another
- Allows movement in multiple planes (multi-axial)
Found in:
- Hip joint (femur and acetabulum)
- Shoulder joint (humerus and glenoid cavity)
2. Hinge Joint
- Works like a door hinge
- Allows movement in one plane only (uniaxial)
- One bone has a cylindrical projection that fits into a trough-like depression of another bone
Found in:
- Elbow (humerus and ulna)
- Knee (femur and tibia)
- Finger joints
3. Pivot Joint
- One bone rotates around another
- Allows rotational movement only
- Cylindrical surface of one bone articulates with a ring formed by another bone
Found in:
- Atlas and axis vertebrae (allows head rotation)
- Radioulnar joint (allows forearm rotation)
4. Gliding Joint
- Flat or slightly curved surfaces that slide over each other
- Allows sliding movements in multiple directions
- Limited range of motion
Found in:
- Between carpals (wrist bones)
- Between tarsals (ankle bones)
- Vertebral facet joints
5. Saddle Joint
- Resembles two saddles fitting together
- Allows movement in two planes (biaxial)
- Both surfaces are concave in one direction and convex in the other
Found in:
- Carpometacarpal joint of the thumb
6. Condyloid Joint
- Oval-shaped projection of one bone fits into oval-shaped depression of another
- Allows movement in two planes (biaxial)
- Similar to ball and socket but more restricted
Found in:
- Wrist joint (radiocarpal joint)
- Metacarpophalangeal joints (knuckles)
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