SubcapitalNeck of Femur Fracture in a Case of Osteonecrosis of Femoral Head – Rare Presentation

INTRODUCTION: Osteonecrosis of femoral head is a common debilitating condition affecting young males most commonly. It is endpoint of a series of events leading to disturbance in the blood supply of femoral head. Rarely, these cases present with acute pain following trivial trauma due to pathological fracture in the neck of femur. We present a rare case of pathological subcapital neck of femur fracture in a case of osteonecrosis of femoral head. These cases should not be confused with post-traumatic neck of femur fracture. CASE REPORT: A 28-year-old male student presented with history of acute pain in right hip and inability to walk after a squatting event. He was diagnosed to have osteonecrosis of bilateral femoral head 1 year back, for which he denied further treatment. On clinical examination, right hip examination was painful with flexion, adduction, and external rotation deformity. Radiological examination revealed fracture at subcapital region in neck of right femur with osteonecrosis of femoral head. After discussing treatment options with the patient, we performed total hip arthroplasty (THA). Harris hip scores improved from 17.1 to 83.5. CONCLUSION: The presentation of osteonecrosis of femoral head with pathological fractures is rare. Furthermore, it is not included in the commonly used classifications. Osteosynthesis of pathological fracture of neck of femur with osteonecrosis of femoral head rarely has good results.THAcan be a good option in these cases with good functional results.