Posterior Full Body View of the Piriformis Muscle

Description

Posterior surface anatomy frames the deep piriformis as it spans from the anterior surface of the sacrum to the superior border of the greater trochanter, running laterally and slightly inferiorly beneath gluteus maximus. The muscle crosses the posterior aspect of the hip joint, lying anterior (deep) to the gluteal musculature and posterior to the pelvic viscera, with its fibers oriented nearly horizontal in the upper buttock. Along its inferior border, the course of the sciatic nerve is classically adjacent as it exits the greater sciatic foramen. Piriformis is a practical landmark because it subdivides the greater sciatic foramen into suprapiriform and infrapiriform compartments, guiding where the superior and inferior gluteal neurovascular bundles emerge. That relationship drives both symptom patterns and procedural planning: deep gluteal pain syndromes, including piriformis-related sciatic nerve irritation, can mimic lumbar radiculopathy, and variant nerve anatomy (common fibular division piercing the muscle) changes risk during injections and posterior hip work. For posterior approaches to the hip, its position relative to the short external rotators and the sciatic nerve is the safety story. Use this asset in gross anatomy and kinesiology teaching to orient learners to the posterior pelvis and buttock, and in pain medicine or sports medicine materials explaining deep gluteal syndrome and image guided piriformis injection targeting. It also fits orthopedic and radiology publications discussing posterior hip surgical corridors, sciatic nerve course, and differential diagnosis of buttock pain. Anatomical accuracy verified by SciePro's Medical Advisory Board.