The long head of the biceps muscle is vulnerable and receptive to both specific and nonspecific infections. This vulnerability is based on a number of factors.
—The long head of the biceps muscle is inserted into the supraglenoid tuberosity and the glenoid ligament by a long tendon (9 cm.), which glides over the head of the humerus, within the capsule of the joint. It is invested with a synovial sheath, which is an evagination of the capsule, and then slides down the bicipital groove. This bursa is closed at its lower end and is 5 cm. long. Codman1 stated: "To my mind it is more properly called a sheath, but is in fact merely an extension of the joint cavity with which it freely communicates."Constant movement of the tendon in a rather shallow groove and relative instability of the shoulder make it possible for