Surgical anatomy of the lateral femoral cutaneous nerve in the groin region

The lateral femoral cutaneous nerve (LFCN) is a sensitive collateral branch of the lumbar plexus that innervates the anterolateral region of the thigh. Its compression at the level of the groin originates a particular syndrome called meralgia paresthetica. Treatment of this neuropathy may involve sectioning or freeing of the nerve, both of which require an appropriate knowledge of its anatomy. Sixty-four groin regions of formaldehydefixed adult cadavers were dissected, recording the relationships of the LFCN to the anterior superior iliac spine (ASIS). The LFCN was identified in all cases; in one case, it originated as a collateral branch of the femoral nerve. The horizontal distance from the ASIS to the LFCN varied from 0 to 45 mm (mean 10.8 mm). 85.9% of LFCN were located at a distance of 20 mm or less from the ASIS. The vertical distance ranged from 0 to 47 mm, with a mean of 17 mm. We did not find significant differences between the distances upon attempting to correlate them with the individual’s height or interiliac distance. The relationship between the LFCN and the ASIS is variable. In most cases, the LFCN is found within a distance of 20 mm or less from the ASIS in both the lateral and cephalocaudal directions, although it may be located as far as 4 cm or more from it. In addition to this, the LFCN may enter the groin region already divided into more than one branch, or may also course through the inguinal ligament.