This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Orthopaedics
Late complication ofAcetabular fracture -a) Avascular necrosis of head of femurb) Avascular necrosis of lilac crestc) Fixed deformity of the hip jointd) Secondary osteoarthritis of hip joint 
Select and explain. 
A. b, B. c, C. ac, D. ad
D: ad
Answer: D: ad 
Explanation: Early complications include sciatic nerve injury and iliofemoral venous thrombosis.
Among late complications, the common problem is development of secondary osteoarthritis. Other possible problems include avascular necrosis (osteonecrosis) of femoral head, Heterotopic ossification and joint stiffness.