Unusual communications of the brachial plexus

The knowledge of innervation of pectoral muscles is important to surgeons performing breast surgeries, axillary lymph node dissection, harvesting pectoralis major/minor for flaps, and during neurotization procedures where the pectoral nerves are particularly at risk. The present case describes the innervation of the pectoral muscles solely by a nerve trunk arising from the ansa pectoralis (AP) - the loop of medial and lateral pectoral nerves. Interestingly, there was also a communication between the AP and roots forming the median nerve. It is imperative for the operating surgeons to be aware of these rare variations in order to prevent denervation and subsequent atrophy of the pectoral musculature.