The medial epicondyle is a bony protrusion that can be felt on the inside part of the elbow. Part of the upper arm bone, or humerus, it occurs at the bottom of the bone where the humerus meets the ulna at the elbow. It is larger and further back on the bone than its counterpart — the lateral epicondyle. The medial epicondyle provides attachment of the ulnar collateral ligament to the pronator teres muscle, near the back of the elbow. When the ulnar nerve that runs along the back of this bone is hit, it is frequently referred to as hitting the funny bone.
Like many bones in the body, the medial epicondyle may be rarely thought about until it is involved in an injury. Fracture of the medial epicondyle represents the third most common elbow fracture in children, especially those 9 to 14 years old. In children and adolescents, the growth plate between the humerus and the ulna is made of cartilage cells that are softer and more susceptible to trauma than fully formed, mature bone. It is possible in extreme injuries for the growth plate to tear from the connection with the bone, resulting in an avulsion fracture.
Medial epicondylitis, or medial epicondyle apophysitis, is typically a more common and less serious injury in children, especially those involved in throwing sports, such as baseball or softball. Repetitive motions, such as pitching or throwing, may exert too much pressure on the growth plate. Inflammation and irritation in this tender area may make the arm painful and swollen. Painful forearm muscles and pain when trying to bend the wrist downward are common symptoms of medial epicondylitis. This condition is often referred to as Little League elbow.
Overused muscles and repetitive motions in adults may also bring on a bout of medial epicondylitis. A golf swing that places undue pressure on the medial epicondyle area may result in golfer’s elbow. Certain incorrectly executed swimming strokes, especially the backstroke, may lead to swimmer’s elbow. The condition may also be brought on by other repetitive tasks, such as using certain hand tools, computer work, or excessive handshaking — none of which have a snappy nickname. Medial epicondylitis should not be confused with tennis elbow, which is a similar and more common injury that occurs in the lateral epicondyle.
Since medial epicondylitis can be chronic if not attended to, it may be best to seek medical care sooner rather than later. Rest, ice, compression, and elevation may be suggested to alleviate the initial pain. Once the pain has subsided, a program of stretching and strengthening may help avoid future injuries to the medial epicondyle area.