The axillary arch muscle (Langer′s muscle): Clinical importance

This was a cadaveric study aimed at studying the incidence of axillary arch muscle and the extent of its different attachments, and discussing its clinical importance. Totally, 30 upper limbs were meticulously dissected to locate the axillary arch. Wherever found, the arch was dissected from its origin to insertion and its nerve supply and blood supply was noted. The dimensions of the arch were measured. Its relations to the structures in axilla were studied in detail. Any additional related variations were investigated. The axillary arch was present in one right upper limb i.e., an incidence of 3.33%. The muscle extended from the lateral border of latissimus dorsi muscle across the axillary vessels and nerves lying superficial to the coracobrachialis, short and long heads of biceps brachii muscles, finally dividing into multiple slips of insertions into fascia covering the deep surface of pectoralis major muscle, fascia covering the biceps brachii muscle, and some slips extending into the capsule of shoulder joint. Across the middle of the axillary arch, a tendinous intersection was observed. The muscle was supplied by a branch of the thoraco-dorsal nerve. The presence of the axillary arch must always be kept in mind due to the possibility of such a muscular arch causing axillary vein entrapment, lymphatic compression, and shoulder instability by neurovascular compression, impeding the access to axillary lymph nodes during breast cancer surgeries and in latissimus dorsi transplants. It may also restrict abduction at shoulder joint