Exit Pattern of Sciatic Nerve: A Cadaveric Study of Nigerians

We carried out a study on the exit pattern of the Sciatic nerve in a sample of Nigerian cadavers. Two hundred and eighty two (282) gluteal regions from one hundred and forty one (141) cadavers were dissected using the protocols designed in Cunningham's dissection manual (15th Edition) and Finley's Interactive Cadaveric Dissection Guide. There were no significant differences in the exit pattern of the Sciatic nerve between the left and right gluteal regions. However the nerve showed significant variations in exit pattern between cadavers. In two hundred and sixty five limbs (94%), the Sciatic nerve emerged as a single trunk at the inferior border of the Piriformis muscle. While in one (1) limb (0.4%), it emerged divided at the inferior border of Piriformis muscle. Patterns were found to be symmetrical in most cadavers, while it was asymmetrical from one gluteal region to the other in other cadavers. Findings from this study will be relevant in many areas of medical and surgical practice including Orthopaedics, Neurology, physical therapy, Anaesthetics and pain management. Data from this study will also assist as baseline for further research on the clinical anatomy of the Sciatic nerve in Nigeria.

Key Words: Sciatic nerve, Cadavers, Exit pattern, Gluteal region