Title: Supracondylar Process

Imaging Findings:
Figure Bony process (arrows) protruding obliquely from the distal third of the anteromedial humerus oriented toward the elbow joint.

Figure The associated ligament of Struthers extending from the distal bony process to the medial epicondyle forms a supracondylar foramen through which the median nerve and brachial artery (or one of its branches) travel (1 ).

Clinical:
Found in 0.6%-2.7% of the population, most common in Europeans. Usually asymptomatic, though may present as a mass. Occasionally, it may produce median nerve compression and claudication of the brachial artery, especially when the elbow is held in pronation and extension (2). Can come to attention upon palpation or during posttraumatic assessment for injuries.

Etiology:
Embryologic vestigial remnant of climbing animals and seen in many reptiles, most marsupials, cats, lemurs and American monkeys (3). Usually found 5-7 cm above the medial epicondyle.

References:
1. Smith RV, Fisher RG: Struthers ligament: source of median nerve compression above elbow: Case report. J Neurosurg 1973; 38:778.
2. Ivins KG: Supracondylar process syndrome: a case report. J Hand Surg 1996; 2: 279-281.
3. Parkinson C: The supracondylar process. Radiology 1954; 62: 556-558.