ANATOMICAL VARIATION IN MID THIGH BIFURCATION OF SCIATIC NERVE AND ITS CLINICAL SIGNIFICANCE

INTRODUCTION : Sciatic Nerve (SN) is the nerve of the posterior compartment of thigh formed in the pelvis from the ventral rami of the L4 to S3 spinal nerves. It leaves the pelvis via the greater sciatic foramen below piriformis and divides into Common Peroneal Nerve (CPN) and Tibial Nerve (TN) at the level of the upper angle of the popliteal fossa. Higher division of the sciatic nerve is the most common variation where the Tibial nerve  and Common peroneal nerve divide at various level from pelvis to the back of thigh. AIMS AND OBJECTIVES: To study the variation in division of sciatic nerve at different levels in the back of thigh . It has clinical and surgical implications.  METHODOLOGY: This study was conducted in Department of Anatomy of Osmania medical college , koti, Hyderabad .During routine undergraduate dissection of total 22 human cadavers properly embalbed and formalin fixed. 20 males and 2 females cadavers (i.e.,0n 44 lower limbs) were dissected during the study .The cadavers with visible trauma or prior surgeries were excluded from Routine study .During the dissection of posterior compartment of thigh, sciatic nerve was identified and carefully dissected. At first, origin was confirmed and then,it was traced down. The variation was identified , noted and photographed. The results were analysed and compared with previous study. RESULTS:  Mid thigh level bifurcation of sciatic nerve was identified in right lower limb of one cadaver . The percentage of higher level of bifurcation among 44 cadavers is 2.5%. CONCLUSION: Sciatic nerve is the main nerve of the lower limb. Considering its variation in bifurcation at different levels is essential for Surgeons, during above and below knee amputations. Orthopaedicians ,in giving limb prosthesis,  Anesthesiologists, while giving nerve blocks. Plastic surgeons Anatomist and researchers.