Cadavaric Study of Variations in Divisions of Sciatic Nerve

Abstract

Introduction: Sciatica is the pain caused by a compression or irritation of the Sciatic Nerve (SN) and the symptoms include nerve pain, numbness, tingling, and weakness. The clinical values are unilateral or bilateral higher break of SN that result in compression of nerve that leads to piriformis syndrome. This pressure on nerve results in paralysis of the supplied muscles and sensory disturbances. Aim: To observe the variations in the site of divisions of SN and relation to the piriformis muscle. Materials and Methods: This cross-sectional study was carried out after taking ethical approval from Institutional Ethical Committee (IEC) of present institute during year 2015 with duration of one and half year at Anatomy Department of GMERS Medical College, Gandhinagar in about 30 properly embalmed cadavers (total 60 lower limb/extremities) during routine dissection. Results: Total of 60 gluteal regions were examined for the variation in the course and division of the SN. Among them in 51 lower limbs (85%) the SN had a normal course after its exit below the piriformis and divided into tibial nerve and common peroneal nerve at the superior angle of popliteal fossa, while in nine lower limbs (15%) there were higher division site of SN observed. Conclusion: During posterior hip operations, this high division develops in sciatica, nerve injury during deep intramuscular injections, piriformis syndrome, failed sciatic nerve block in anesthesia and injury. Lower limb surgeries and in the interpretation of sciatic neuropathy can be complicated by variation in division of SN.

Keywords

• common peroneal nerve
• piriformis muscle
• tibial nerve