Anatomical variations in the level of bifurcation of the sciatic nerve in Ethiopia

Background : The sciatic nerve, the largest nerve in the body is derived from the sacral plexus. It is composed of tibial and common fibular nerves; the division of this nerve varies; it may occur within the pelvis, gluteal region, upper, mid and lower part of thigh. Injury of the nerve may lead to loss of sensation in posterior thigh, whole leg and foot. The anatomical variations of the level at which the sciatic nerve divides is considered important by clinicians during neuromuscular diagnosis and treatments of the lower limb. Objective : To determine the level of sciatic nerve bifurcation and its side symmetry. Materials and Methods : Observational based descriptive study was conducted to determine the variation of sciatic nerve level of bifurcation on 25 human preserved cadavers. The data were analyzed manually using numbers, frequencies and percentages. Results : The findings of this study states that in 4 limbs (8%), the nerve divided in the pelvis region; in 2 limbs (4%), in the gluteal region; in 12 limbs (24%), at upper, middle and lower part of the posterior. The highest incidence of division occurs in 32 limbs (64%) in the popliteal fossa; in addition 8 (32%) of the 25 cadavers were asymmetrical between right and left sides. Conclusion : The findings of this study revealed that the majority of sciatic nerve divisions occur in the popliteal fossa while some divided into other regions such as pelvis, gluteal and thigh regions. Key words : Bifurcation, common peroneal nerve, ethiopia, sciatic nerve, symmetry, tibial nerve