Quadratus Femoris

Description

Centered on the deep posterior hip, the quadratus femoris spans from the lateral border of the ischial tuberosity to the intertrochanteric crest of the proximal femur (quadrate tubercle region), forming a thick, rectangular band oriented nearly horizontal in anatomical position. Superior to it lies the superior gemellus closely apposed to the obturator internus tendon as it turns laterally toward the greater trochanter, while inferior and anteromedial fibers transition toward adductor magnus along the posterior thigh compartment. The femoral head sits within the acetabulum, and the posterior pelvis frames the field, including the sacrum and adjacent lower lumbar vertebrae. Dense muscle. Clear landmarks. Quadratus femoris is a primary external rotator of the hip and a practical landmark when teaching the layered arrangement of the short lateral rotators beneath gluteus maximus. This relationship matters in posterior hip approaches and in understanding why quadratus femoris can be strained in athletes with forced hip internal rotation and adduction, producing deep buttock pain that can mimic piriformis syndrome. Its close proximity to the medial circumflex femoral artery and the posterior hip capsule makes the muscle a useful orientation point when discussing vascular supply to the femoral head and the potential implications of surgical dissection or trauma around the intertrochanteric crest. Anatomy faculty can drop this plate directly into a pelvic anatomy lab guide to contrast quadratus femoris with the gemelli and obturator internus in a single teaching view, and orthopedic authors can pair it with a posterior total hip arthroplasty chapter to anchor discussion of short external rotator repair. Sports medicine and radiology teams may also use it to contextualize MRI findings of quadratus femoris edema in ischiofemoral impingement between the lesser trochanter and ischium. Anatomical accuracy verified by SciePro's Medical Advisory Board.