This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Pelvis and Hip injuries, Subject name: Orthopaedics
Late complication of Acetabular fracture: 
Select and explain. 
A. Avascular necrosis of head of femur, B. Avascular necrosis of lilac crest, C. Fixed deformity of the hip joint, D. Secondary osteoahritis of hip joint
A: Avascular necrosis of head of femur
Answer: A: Avascular necrosis of head of femur 
Explanation: *Early complication include sciatic nerve injury and iliofemoral venous thrombosis. Among late complication the common problem is development of secondary osteoahritis.other possible problems include Avascular necrosis of femoral head, Heterotopic ossification and joint stiffness. Early complications: 1-Venous Thromboembolism. 2-Neurovascular injury: Sciatic nerve, the lateral femoral cutaneous nerve, Femoral nerve, Superior gluteal bundle and the iliofemoral vessels. 3-Intraaicular hardware. 4-Malreducton. 5-Failure of fixation. 6-Infection. Late complications: 1-Avascular necrosis: femoral or acetabular. 2-Posttraumatic Ahritis. 3-Heterotopic Ossification. 4-Nonunion. Ref: Apley's 9th/e p.840,841