Dual Innervation in Anterolateral Thigh (ALT) Phalloplasty: Consider the Femoral Perforating Nerves

Abstract

Background: Sensation following anterolateral thigh (ALT) phalloplasty is traditionally viewed as inferior to sensation following radial forearm phalloplasty, potentially due to fewer nerve coaptations performed. Neural anatomy of the ALT is well described, with branches of the femoral nerve innervating the medial flap. The purpose of this article is to draw attention to these nerves as a potential source of additional coaptation in ALT phalloplasty allowing for dual flap innervation. Methods: A PRISMA literature review was conducted to assess nerve coaptations used in ALT phalloplasty. Anatomic location and territory of the nerves of the thigh in ALT phalloplasty cases are reviewed. Results: Seventeen articles discuss ALT phalloplasty innervation, and 16 mention the use of only one nerve coaptation with the lateral femoral cutaneous nerve. In our experience performing ALT phalloplasty, perforating branch(es) of the femoral nerve are the first nerve(s) encountered on the medial border of the ALT flap lying on the fascia over the sartorius. With a flap design where the urethra is based laterally, the femoral perforating nerves can innervate a significant portion of the phallic shaft (medial flap), where sensation is most desired. Conclusions: It is common practice to perform only one nerve coaptation in ALT phalloplasty with the lateral femoral cutaneous nerve. However, perforating branches of the femoral nerve consistently innervate medial skin of the ALT. The authors propose that the femoral perforating nerves, when present, can be used as additional nerves for coaptation in ALT phalloplasty to allow for dual innervation.