A Variant of the Sciatic Nerve and its Clinical Implications

Abstract

Variants of gluteal neural anatomy are important to consider, especially during surgical approaches to the hip. During the routine dissection of the gluteal region, a variant of the sciatic nerve was found where the nerve left the pelvis fully split into its tibial and common fibular components. Intrapelvically and extrapelvically, there was no splitting of the two components by the piriformis muscle. Distally, the two parts of the nerve were draped over the medial and lateral edges of the ischial tuberosity. To avoid iatrogenic injury to the sciatic nerve during invasive or surgical approaches to this region, all possible anatomical variations, such as the one presented herein, should be appreciated by the clinician.

Keywords: anatomy; gluteal region; iatrogenic; nerve injury; posterior thigh; surgery.

Figure 1. Variant right sciatic nerve.

Note the sciatic nerve is united just inferior to the piriformis muscle. However, distal to this location, the nerve is split around the ischial tuberosity with the tibial nerve being located lateral to the ischial tuberosity. Distal to this, the two components travel more closely together but remain ununited.