Deep axillary arch muscle; a rare muscular variation

Axillary or Langer's arch muscle is one of the rare anatomical variations in the axillary region. It is a muscular band running from latissimus dorsi to pectoralis major, biceps brachii or coracoid process and it can be deep or superficial. In its course it is closely related to the nerves and vessels of the axillary region. The evolution of this muscle states that it is a remnant of panniculus carnosus, which is an extensive subcutaneous sheet of muscle. In clinical practice it is seen associated with costoclavicular compression syndrome, neurovascular entrapment, thoracic outlet syndrome and it leads to confusion in routine axillary clearance in breast cancer. The anatomical knowledge of this variation is of great use for surgeons, clinicians and radiologists in interpreting axillary mass. We report an anomalous axillary arch muscle, its morphology and clinical significance had been reviewed.