Figure 1
From: Variations in branching of the posterior cord of brachial plexus in a Kenyan population
Photomacrographs of axillary region showing posterior cord of the brachial plexus and its branches. A: Common trunk giving rise to upper subscapular (US), thoracodorsal (TD) and lower subscapular (LS) nerves from the posterior cord (PC). Axillary nerve (AN) emerges as a separate branch. B: Supraclavicular origin of axillary nerve (AN) from posterior cord (PC). It gives off upper subscapular (US) and lower subscapular (LS) nerves. Thoracodorsal (TD) nerve emerges as a separate branch form the PC. C: Infraclavicular origin of axillary nerve (AN) from posterior cord (PC). It gives off upper subscapular (US) and lower subscapular (LS) nerves. Thoracodorsal (TD) nerve emerges as a separate branch form the PC. D: Axillary nerve (AN) from posterior cord (PC) giving a common trunk that separates into lower subscapular (LS) and thoracodorsal (TD) nerves. Upper subscapular (US) emerges separately from the AN. E: Axillary nerve (AN) giving upper subscapular (US), middle subscapular (MS) and lower subscapular (LS) nerves. Thoracodorsal (TD) nerve emerges separately from the posterior cord (PC). F: Common subscapular (CS) from the posterior cord (PC) that divides into upper subscapular (US) and lower subscapular (LS) nerves. Axillary nerve (AN) and Thoracodorsal (TD) emerge as separate branches from the posterior cord (PC). In this specimen, the PC further gave rise to the medial cutaneous nerve of the arm (Mcna) and medial cutaneous nerve of the forearm (Mcnfa).