A rare case of bilateral high division of sciatic nerve (of different types) with unilateral divided piriformis and unusual high origin of genicular branch of common fibular nerve

Yusuf Saleem KHAN K, Tasneem K

Abstract

We report a very rare case of two different types of high divisions of sciatic nerve (SN) on either side of a 33-year-old female cadaver with unilateral divided piriformis muscle. Here SN of either side divided into tibial and common fibular nerves within pelvis and entered into gluteal region. On the right side both divisions passed below piriformis, but on the left side the common fibular nerve passed between two divisions of divided piriformis, while tibial nerve passed below the inferior piriformis. What is rare is not high division of SN, but to find two different types of high divisions of SN on either side of same cadaver with unilateral bifid piriformis as found here. To our knowledge, there is no literature describing this kind of variation. Also seen was an unusual finding of unilateral high origin of genicular branch of left common fibular nerve. This combination of variations makes this case the most interesting and unique of its kind.