The capitulum of the humerus is an eminence in the human arm that is a smooth, rounded protuberance at the lateral portion of the humerus’ articular surface. It is pressed up against the depression at the head of the radius, and is located only on the lower front area of the bone. The capitulum of the humerus should not be confused with the trochlea, which is a pointed protuberance that is adjacent to the capitulum.