epicondyle

An epicondyle is a bony prominence located above a condyle on a long bone, serving as an attachment site for ligaments and muscles. In the upper limb, the humerus has medial and lateral epicondyles near the elbow. The medial epicondyle lies on the inner side of the distal humerus and serves as the origin for the common flexor tendon, contributing to wrist and finger flexion. The lateral epicondyle lies on the outer side and is the origin for the extensor muscles that extend the wrist and fingers. The ulnar nerve runs in close opposition to the medial epicondyle, behind it in the cubital tunnel.

Clinical relevance includes injuries and overuse at these sites. Epicondylitis denotes painful overuse of the epicondyle area: lateral epicondylitis, commonly known as tennis elbow, affects the extensor tendon origin; medial epicondylitis, or golfer’s elbow, involves the flexor tendon origin. Fractures or avulsions of the epicondyle can occur, particularly in children with elbow injuries, and injuries to the nearby ulnar nerve can produce sensory and motor symptoms.

Diagnosis typically relies on history and localized tenderness over the epicondyle, with resisted muscle testing and imaging as needed to exclude fracture or other pathology. Treatment emphasizes activity modification, pain management, physical therapy, and gradual return to function; most cases improve with conservative management, while surgery is reserved for severe or refractory instances. Similar bony projections known as epicondyles exist on other bones, such as the distal femur, where medial and lateral epicondyles provide attachment points for ligaments and muscles.