Anatomical Variations of the Sciatic Nerve Exit from the Pelvis and Its Relationship with the Piriformis Muscle: A Cadaveric Study

Abstract

Background: The sciatic nerve (SN) is the widest nerve of the human body that exits the pelvis through the greater sciatic foramen, usually below the piriformis muscle (PM), and descends between the greater trochanter of the femur and ischial tuberosity of the pelvis to the knee. The aim of this paper is to examine and identify the SN variations in relation to the PM, its prevalence, pattern, and course. Methods: A prospective-descriptive cross-sectional study was carried out to determine the frequency of anatomical variations in the exit of the SN in relation with the PM in 20 anatomical bodies (corpses) of both genders, in equal numbers. Results: The dissection of 40 SNs in corpses of both sexes in equal numbers showed that the SN exited inferior to the PM in 37 lower limbs (92.5%); between the fascicles of the PM and inferior to the PM in two lower limbs (5%); and in one thigh, between the fascicles of the PM and superior to the PM (2.5%). Our study reported that the SN divides in its terminal branches more commonly in the proximal part of the popliteal fossa in 55% of cases, in the gluteal region in 35% of cases, and in the middle third of the thigh in 10% of cases. Conclusions: Anatomical variations of the SN in relation to the PM are challenging for the diagnostic and therapeutic procedure in many clinical and surgical cases. Rapid recognition of the SN changes makes surgical approaches more accurate and effective. Our study confirmed that the SN exits the pelvis most commonly below the PM, although some anatomical variations may occur.

On the balance beam: facing the challenges of neurosurgical education in the third millennium

“…[ 25 ] In addition, incorporating interprofessional education into the training curriculum can enhance trainees’ understanding of team dynamics and improve patient care. [ 9 , 18 , 26 ]…”

“…[25] In addition, incorporating interprofessional education into the training curriculum can enhance trainees' understanding of team dynamics and improve patient care. [9,18,26] e transition from trainee to independent practitioner represents a critical phase in a neurosurgeon's career. It signifies a shift in responsibility, demanding a deeper understanding of the real-world implications of neurosurgical care.…”

Enhancing microsurgical skills in neurosurgery residents of low-income countries: A comprehensive guide

“…The resident’s job consists of brain extraction during the autopsy, fixation process, vessel repletion, macro, and microscopic study, meticulously caring for the specimen in each phase, and the cutting and final inclusions of lamellae are done by the pathological anatomy service. [ 10 , 38 ] In this document, each of the processes of the brain specimen is detailed and recorded in a specific and meticulous way; however, it is not part of the present work and leaves the objectives of this, so only mention of it is made. Even if it does not take long for residents to understand the altruism of body donors and the educational contributions they have made to their education and career preparation, it is important to instill in residents a deep respect for the incredible gift of learning that donors have given to science.…”

Assessment in location of sciatic nerve between the ischial tuberosity and the greater trochanter of the femur: A cadaveric study

“…Sciatic nerve (SN) is the widest and longest peripheral nerve in human body, it originates from sacral plexus in pelvic cavity and penetrates the greater sciatic foramen to emerge in gluteal region, and then it continues down the posterior compartment of the thigh [ 1 ]. The course of SN in gluteal region is clinically practical for many medical procedures such as SN block [ 2 ].…”

“…We initially considered that racial and geographic differences were contributions to the different location descriptions for adult. However, we find many figures in publications from many countries involving living human bodies and cadavers from different races show SN is closer to IT than to GT [ [1] , [2] , [3] , [4] , [5] , [6] , [7] , [8] , [9] , [10] , [11] , [12] , [13] , [14] ]. Based on the teaching experience in human anatomy, we realize the selected landmark is another cause we should take seriously, because different landmarks get different location descriptions.…”