DOI: 10.36347/sjams.2019.v07i05.047

Pages: 1925-1932

Background: The Sciatic nerve is the widest nerve of the body. It consists of two components, namely: the tibia and the common peroneal components derived from the ventral rami of L4 to S3 spinal nerves of the lumbosacral plexus. It exits the pelvis through the greater sciatic foramen below the Piriformis muscle and descends between the greater trochanter of the femur and ischial tuberosity of the pelvis to the knee. Higher division of the sciatic nerve is the most common variation where the TN and CPN may leave the pelvis through different routes which may lead to various clinical manifestations Likewise, their adequate knowledge will help in increasing surgical precision and decreasing morbidity. Material and methods: The study is a descriptive cross-sectional study conducted at the department of anatomy of several medical faculties in Sudan from May 2016 to June 2017. In which 50 male cadaver (100 lower extremities) age ranges from 50 to 70 years were dissected to level the bifurcation. Result: In the 100 explored sciatic nerves we get fife types of bifurcation; Inside the pelvis, High up in the gluteal region & upper third of the back of the thigh , The middle of the back of the thigh, The lower of the back of the thigh & At Popleteal fossa with the last one been the most frequently reported variant. One variant is the nerve exit the pelvis as two roots united at the gluteal region to divide again at the poplteal fossa. Discussion: According to the literature, the anatomical variant described in 50 cadavers is considered relatively not rare. Conclusion: The most frequent reported nerve is that nerve exiting the pelvis as sciatic nerve 79 %(78 – 80 %), passing anterior to piriformis 92% (90 – 94%),posterior to; superior gemelli 92%, obturator internus, inferior gemilli, quadrates femoris 100%.In the 20% of nerves (10 cadaver) with pelvic division the tibial component is keeping the anterior relation to piriformis in all cases & in both side, while the c