Langer's axillary arch

Case Discussion

During a visit for breast cancer screening, a right axilla concavity significant loss was observed. The woman was asymptomatic, in particular, she had no history of vascular or neurologic disorders of the right arm (i.e. periodic axillary vein thrombosis or complaints of sensory and motor dysfunction).

Ultrasounds of the right axilla show an isoechoic muscular structure 10 mm in diameter, extending from the lateral edge of the latissimus dorsi to the tendon of insertion of the pectoralis major. The diagnosis is that of Langer's axillary arch (LAA). The contralateral axilla clinically and scanned by ultrasound was normal.

This is the first described case of Langer's axillary arch (LAA) detected by clinical observation and ultrasound.

Langer's axillary arch (LAA) is an anomalous muscular variant that extends from the lateral edge of the latissimus dorsi across the axillary vessels and the distal brachial plexus into the tendon of insertion of the pectoralis major or to the coracoid process.

In the literature, it is described as axillary or axillopectoral arch or muscle and has its name – Langer’s arch or muscle – after the Austrian anatomist who first described this anatomical variant in the 19th century.

This arch, which is the main anatomic variation in the axilla, is present in ~7% of the general population (range 0.25% to 27%).

LAA is usually discovered during routine axillary surgery in patients with breast cancer or during autopsy, more rarely by CT or MRI due to symptoms of vascular or neurologic disorders of the arm.