Definition: A Hill-Sachs lesion is an injury that causes damage to the head of the humerus (arm bone). A Hill-Sachs lesion is a complication of a shoulder dislocation. When the shoulder dislocates, the smooth cartilage surface of the humerus hits against the rim of the scapula (glenoid).
The Hill-Sachs injury is caused when the humeral head is impinged against the glenoid of the shoulder joint. The Hill-Sachs lesion can usually be seen on a normal shoulder x-ray.
