Abstract
This paper highlights the fact that full length labral tears are a cause of instability in posterior fracture-dislocations of the hip.
From July 1994 to March 2001, 133 consecutive posterior fracture-dislocations of the hip were surgically treated. On admission, all patients were initially subjected to closed reduction, and in some cases skeletal or skin traction was applied. Pelvic radiographs were taken to confirm relocation, and CT done to look for intra-articular bone fragments. Intra-operative findings and surgical technique were recorded.
Redislocation occurred in eight patients, whose surgical notes were reviewed to determine the cause. Despite 9 kg of skeletal traction, one patients’s hip redislocated the day after closed reduction. In the other seven, redislocation occurred postoperatively. The time to redislocation varied from one day to 16 weeks, and because redislocation was sometimes painless, not all patients reported it immediately.
Two patients, whose radiographs showed very small fragments at the superior-posterior position, would normally have been treated conservatively. On one, surgery was performed because the fragment was lodged at the weight-bearing area of the joint. The hip of the other redislocated on skeletal traction the day after closed reduction. At surgery, it was noted that both patients had extensive soft tissue stripping and full length tears of the labrum. The other six patients had clear posterior wall fractures requiring surgical reconstruction. The fragments were often attached to the capsule but were too small to fix with screws, so buttress plating was used alone.
Full-length labral tears in posterior dislocations of the hip cause instability, and failure to address this adequately at surgery may result in redislocation.
The abstracts were prepared by Professor M. B. E. Sweet. Correspondence should be addressed to him at The Department of Orthopaedic Surgery, Medical School, University of Witwatersrand, 7 York Road, Parktown, Johannesburg, 2193 South Africa