Bilateral high division of the sciatic nerve: incidence and clinical implications in Nigeria.

Abstract

Introduction: The sciatic nerve (L4-S3) comprised of the tibial and common fibular (peroneal) components contained in the same epineural sheath usually leaves the pelvis via the greater sciatic foramen beneath the piriformis muscle. They usually separate in the lower thigh above the popiteal fossa. Variations in this arrangement have been reported. We noted one such variation in our study.
Materials / Methods: The gluteal region and posterior thigh of 26 cadavers were dissected over a two session period (2004/05 and 2005/06) with emphasis on the sciatic nerves and its related structures.
Results: One out of the twenty-six had the sciatic nerve dividing into its two main branches in the pelvis and the common peroneal passing over the piriformis muscle as it enters the posterior thigh.
Conclusion: High division of the sciatic nerve is seen in 3.8% of Nigerians and could predispose to injury during intragluteal injection, may be the cause of piriformis syndrome, sciatica, failed sciatic nerve block in anesthesia and predispose to injury during posterior hip operations.


Keywords: Sciatic nerve, high division, nerve injury, nerve block.

Tropical Journal of Medical Research Vol. 11 (2) 2007: pp. 12-13