Optimizing Innervation in Radial Forearm Phalloplasty: Consider the Posterior Antebrachial Cutaneous Nerve

Summary: One goal of an ideal phallic reconstruction is achieving tactile and erogenous sensation. Traditionally, the most common flap used in phalloplasty has been the radial forearm flap, where the medial and lateral antebrachial cutaneous nerves are coapted to meet this goal. The purpose of this article is to draw attention to the lesser-known posterior antebrachial cutaneous nerve (PABC) as an alternative or additional nerve for coaptation that innervates a majority of the shaft, where sensation is most desired. The presence, anatomical location, and territory of innervation of the antebrachial cutaneous nerves were assessed in a series of 12 consecutive in vivo radial forearm phalloplasties. A literature review was conducted to establish which nerves have traditionally been used for sensory reinnervation of the phallus. The PABC was the first nerve encountered on the radial border of the flap lying on the fascia in the interval between the brachioradialis and extensor carpi radials longus. The posterior and lateral antebrachial cutaneous nerves innervated the phallic shaft, whereas the anterior branch of the medial antebrachial cutaneous nerve innervated the phallic urethra. There were no articles in our review that used PABC for nerve coaptation in radial forearm phalloplasty. The skin innervated by the PABC represents a significant portion of the phallic shaft when using the standard template for radial forearm phalloplasty. Despite this, its use is not described in the literature. The authors introduce the PABC as an alternative or additional nerve for coaptation in radial forearm phalloplasty.