Quadratus femoris tear as an unusual cause of hip pain: a case report.

To show that quadratus femoris muscle partial or complete tear is an extremely rare if not underdiagnosed cause of hip pain.We present the case of a 75-year-old Caucasian woman with spontaneous non-traumatic quadratus femoris tear.Computed Tomography showed quadratus femoris tear with occult underlying ischiofemoral impingement pathology.Quadratus femoris muscle is a hip external rotator and adductor and is situated along the posterior aspect of the hip joint and its proximity of anatomy with other external rotators leads to diagnostic pitfalls for radiologists. Identification of the exact muscle tear will establish the diagnosis, guide the proper physical therapy and reliably inform the patient what to expect after treatment.