[Quadratus femoris muscle tear].

BACKGROUND: Quadratus femoris tear is an uncommon injury that usually cause hip pain, it incidence is unknown. The patient can suffer of posterior gluteal pain or groin pain or both, which makes accurate diagnosis difficult, because the differential diagnosis of hip pain is broad.

CLINICAL CASE: A 65 years old male, with gluteal and groin pain presented during tennis; evaluated by neurologist with lumbosacral magnetic resonance imaging (MRI) (normal) and referred to physical therapy, a pelvic MRI was required, finding an unsuspected quadratus femoris tear.

CONCLUSION: MRI with its superior soft-tissue resolution and multiplanar capability is an excellent adjunct to physical examination because it shows the anatomic location of the abnormality, aiding the clinician to make unsuspected diagnoses.