[The axillo-pectoral muscle and Karl Langer: an anatomical variation and a rather unknown great anatomist].

Langer's axillo-pectoral muscle is a musculotendinous structure, that is transversally situated in the axilla. It is an anatomic anomaly rather unknown, but important for the surgeon. The anatomic description of this structure, the clinical signs and the surgical implications are reported. Finally, the biography of Langer, who gave his name to the anomaly, is outlined.