A cadaveric study about the localization of sciatic nerve separation point in Thais: Implications for nerve block.

ABSTRACT

Objectives: The aim of this study was to evaluate the distance of the separation point of sciatic nerve in popliteal fossa and its relation to the length of femur in Thai cadavers. Method: One hundred and six Thai cadavers which composed of 105 right legs and 106 left legs were examined in this study. After dissection of the popliteal fossa, the distance of the separation point of the sciatic nerve above the level of both femoral epicondyles was measured in 84 right legs and 89 left legs of 66 male and 40 female cadavers. In addition the length of femur, which was the distance from posterior edge of the greater trochanter to the most prominent point of lateral epicondyles, was recorded. Results: In the specimen of this study, the sciatic nerves separated at a mean distance of 8.72 + 4.35 cm and 7.32 + 3.03 cm above the level of both femoral epicondyles in male and female cadavers with the highly variation range from 2.1 to 30.7 cm. The mean distances of the right and left legs in male cadavers were 8.49 + 4.39 and 8.90 + 4.32 cm respectively, being longer than in female cadavers (7.32 + 3.67 and 7.28 + 2.30 cm respectively) There were no significant differences in both the distance of the separation point and the length of femur by sex or side. Conclusion: The distances of the separation point of the sciatic nerve above the level of both epicondyles in Thai cadavers were highly variable and not related with the length of the femur.