Supracondylar process of the humerus Supracondylar process of the humerus The supracondylar process of the humerus (also known as an "avian spur") is a bony projection on the anteromedial aspect of the upper arm bone (humerus), about 5 cm above the medial epicondyle. It is directed downward, forward and medially pointing to the medial epicondyle. It is an anatomical variation which occurs in about one percent of all people. A fibrous band, Struthers ligament, may connect this process to the medial epicondyle. Supracondylar processes are usually asymptomatic, but may be palpable as a mass on the upper arm. They are most commonly found as an
Ossification of humerus head of the bone, and during the second year the center for the greater tubercle, and during the fifth that for the lesser tubercle, make their appearance. By the sixth year the centers for the head and tubercles have joined, so as to form a single large epiphysis, which fuses with the body about the twentieth year. The lower end of the humerus is ossified as follows. At the end of the second year ossification begins in the capitulum, and extends medialward, to form the chief part of the articular end of the bone; the center for the medial part