A muscle haematoma of the quadriceps femoris muscle, marked by severe and prolonged pain. It is caused by direct trauma and is a common injury in contact sports, such as American Football. In its mild form, it is often called a ‘dead leg’. This mild condition usually resolves itself within a week. In its severe form, a charley horse can cause much internal swelling and is sometimes linked with the development of calcium and bone in the muscle (see myositis ossificans). The term has also been used for similar hamstring injuries.
Subjects: Sports and Exercise Medicine.