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: Surgery
Kocher Langenbeck approach for emergency acetabular fixation is done in all, EXCEPT: 
Select and explain. 
A. Open fracture, B. Progressive sciatic nerve injury, C. Recurrent dislocation in spite of closed reduction and traction, D. Open irrigation and debridement of the hip joint
B: Progressive sciatic nerve injury
Answer: B: Progressive sciatic nerve injury 
Explanation: Indications for Kocher Langenbeck approach: 1. Open reduction and internal fixation of acetabular fractures Posterior wall Posterior column Transverse posterior wall Posterior column-posterior wall T-type Transverse 2. Open irrigation and debridement of the hip joint 3. Recurrent dislocation in spite of closed reduction and traction Ref: Relevant surgical exposures edited by Bernard F. Morrey, M.D., Matthew C. Morrey, 2008, Page 134.