Snapshot A 54-year-old woman presents with right groin and buttock pain. She denies any recent history of trauma or fall on the affected area. Medical history is significant for multiple sclerosis (MS) that required systemic steroids due to a MS exacerbation. On physical exam, there is decreased passive and active range of motion of the hip. Magnetic resonance imaging demonstrates serpiginous peripheral sclerosis with inner granulation tissue. Introduction Clinical definition login to view 2 more bullets Epidemiology Incidence login to view 1 more bullet Demographics login to view 2 more bullets Etiology Pathogenesis login to view 6 more bullets Traumatic login to view 4 more bullets Atraumatic login to view 11 more bullets Presentation Symptoms login to view 7 more bullets Physical exam login to view 3 more bullets Imaging Radiographs login to view 2 more bullets Magnetic resonance imaging (MRI) login to view 4 more bullets Studies Making the diagnosis login to view 1 more bullet Differential Stress fracture Degenerative joint disease Treatment Management approach login to view 2 more bullets Complications Collapse of femoral head in cases of femoral involvement Degenerative joint disease Focal osteoporosis Prognosis Dependent on the extent of the lesion