The lateral femoral cutaneous nerve canal.

OBJECTIVE Meralgia paresthetica causes dysesthesias and burning in the anterolateral thigh. Surgical treatment includes nerve transection or decompression. Finding the nerve in surgery is very challenging. The author conducted a cadaveric study to better understand the variations in the anatomy of the lateral femoral cutaneous nerve (LFCN). METHODS Twenty embalmed cadavers were used for this study. The author studied the LFCN's relationship to different fascial planes, and the distance from the anterior superior iliac spine (ASIS). RESULTS A complete fascial canal was found to surround the nerve completely in all specimens. The canal starts at the inguinal ligament proximally and follows the nerve beyond its terminal branches. The nerve could be anywhere from 6.5 cm medial to the ASIS to 6 cm lateral to the ASIS. In the latter case, the nerve may lodge in a groove in the iliac crest. Other anatomical variations found were the LFCN arising from the femoral nerve, and a duplicated nerve. A thick nerve was found in 1 case in which it was riding over the ASIS. CONCLUSIONS The variability in the course of the LFCN can create difficulty in surgical exposure. The newly defined LFCN canal renders exposure even more challenging. This calls for high-resolution pre- or intraoperative imaging for better localization of the nerve.