Elbow Joint:Anatomy,Movement & Muscle involvement
The elbow is a synovial variety of hinge joint, formed within the distal end of the humerus and the proximal ends of the ulna and radius in the forearm. The elbow permits for the flexion and extension of the forearm, as well as rotation of the forearm and wrist.
Articulating Surfaces of the Elbow Joint
Joint Capsule and Bursae of the Elbow Joint
The elbow joint has a capsule enclosing the joint. This joint capsule strengthening the elbow joint. The joint capsule is thickened medially and laterally to form collateral ligaments, which stabilize extending the and flexing motion of the elbow joint.
A bursa is a membranous sac loaded with synovial fluid. It functions to cushion the moving parts of a joint. There are many bursae in the elbow, but a few have clinical significance-
Intratendinous – positioned within the tendon of the triceps brachii.
Subtendinous – within the olecranon and the tendon of the triceps brachii muscle, diminishing friction between the two structures during extension and flexion of the arm.
Subcutaneous – within the olecranon and the overlying connective tissue.
Ligaments of the Elbow Joint
The joint capsule of the elbow is strengthened by ligaments medially and laterally.
The ulnar collateral ligament originates from the medial epicondyle and attaches to the coronoid process and olecranon of the ulna.
The radial collateral ligament is located on the lateral side of the joint, extending from the lateral epicondyle, and blending with the annular ligament of the radius.