Types
There are six types of synovial joints. Some are relatively immobile, but are more stable. Others have multiple degrees of freedom, but at the expense of greater risk of injury. In ascending order of mobility, they are:
| Name | Example | Description |
|---|---|---|
| Gliding joints (or planar joints) | carpals of the wrist, acromioclavicular joint | These joints allow only gliding or sliding movements |
| Hinge joints | elbow (between the humerus and the ulna) | These joints act as a door hinge does, allowing flexion and extension in just one plane |
| Pivot joints | atlanto-axial joint, proximal radioulnar joint, and distal radioulnar joint | One bone rotates about another |
| Condyloid joints (or ellipsoidal joints) | wrist joint (radiocarpal joint) temporomandibular joint | A condyloid joint is where two bones fit together with an odd shape (e.g. an ellipse), and one bone is concave, the other convex; some classifications make a distinction between condyloid and ellipsoid joints; these joints allow flexion, extension, abduction, and adduction movements (circumduction). |
| Saddle joints | Carpometacarpal or trapeziometacarpal joint of thumb (between the metacarpal and carpal - trapezium), sternoclavicular joint | Saddle joints, which resemble a saddle, permit the same movements as the condyloid joints |
| Ball and socket joints
"universal Joint" |
shoulder (glenohumeral) and hip joints | These allow for all movements except gliding |
| Compound joints / modified hinge joints | knee joint | condylar joint (condyles of femur join with condyles of tibia) and saddle joint (lower end of femur joins with patella) |
Read more about this topic: Synovial Joint
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