The axillopectoral muscle [Langer’s arm arch (LAA)], is described as a supernumerary musculo-tendino-fascial structure, which connects at least two muscles that make up the walls of the axillary fossa. This anatomical variant is found in around 7% and 15% of the population, usually unilaterally, on the right side and in females. Kaplan described a nervous communication between the dorsal and the terminal superficial branches of the ulnar nerve, both sensory, with an incidence of the 2% to 4%.
A case report is presented of an anatomical preparation, in which Langer’s arm arch and Kaplan anastomosis coexisted on both sides. A review of literature of LAA and Kaplan’s anastomosis is also presented. The knowledge of these anatomical variations is important as they are involved in a wide variety of vascular, nervous and functional disorders of the upper limb.