Eur J Anat, 20 (4): 365-369 (2016)

Anatomical variation of sciatic nerve: a case report of high division and unusual anastomosis with the posterior femoral cutaneous nerve

Lucas A.S. Pires¹, Carlos A.A. Chagas¹, Rodrigo M.P. Fernandes^1,2, Celso R.C.M. Silva³, Max A. Cavalcante³, Márcio A. Babinski^1,3

¹Morphology Department, Biomedical Institute, Fluminense Federal University, Niterói, Rio de Janeiro, Brazil, ²Medical Sciences Post-Graduation, Fluminense Federal University, Niterói, Rio de Janeiro, Brazil, ³Traumatology and Orthopedic Service of the Salgado Filho Hospital, Rio de Janeiro, Brazil

ABSTRACT The posterior femoral cutaneous nerve is a sensitive nerve that rises from S1-S3, usually giving off cutaneous branches for the gluteal region, perineum, the posterior region of the thigh and leg. The sciatic nerve is the largest nerve in the human body, rising from L4-S3, and divides into the tibial and common fibular nerves, innervating the muscles from the posterior compartment of the thigh. Anastomosis between the sciatic nerve and the posterior femoral cutaneous nerve is rare. During dissection of the right gluteal region on a male cadaver fixed with 10% formalin, we observed an anastomosis between both nerves, while the common fibular nerve perforated the piriformis muscle, dividing it in two muscle slips. Both nerves trajectories  were within the regular pattern after this communication. Our aims were to describe this unusual case of anastomosis and perform a literature review on the variations of the sciatic nerve, while also discussing their clinical significance.

Keywords: Anatomic variation, Nervous anastomosis, Sciatic nerve, Posterior femoral cutaneous nerve, Piriformis muscle