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Residual hip dysplasia: is there a place for hip shelf operation?
1Department of Orthopaedics, Oslo University Hospital, Rikshospitalet, Oslo, Norway.
Purpose:
After modern acetabular osteotomies were introduced, hip shelf operations have become much less commonly used. The aims of this study were to assess the short-term and long-term outcome of a modified Spitzy shelf procedure and to compare the results with those of periacetabular osteotomy (PAO).
Methods:
In all, 44 patients (55 hips) with developmental dysplasia of the hip and residual dysplasia had a modified Spitzy shelf operation. Mean age at surgery was 13.2 years (8 to 22). Indication for surgery was a centre-edge angle < 20° with or without hip pain. Outcome was evaluated using duration of painless period and survival analysis with conversion to total hip arthroplasty (THA) as endpoints.
Results:
Preoperative hip pain was present in 46% of the hips and was more common in patients ≥ 12 years at surgery (p < 0.001). One year postoperatively, 93% of the hips were painless. Analysis of pain in hips with more than ten years follow-up showed a mean postoperative painless period of 20.0 years (0 to 49). In all, 44 hips (80%) had undergone THA at a mean patient age of 50.5 years (37 to 63). Mean survival of the shelf procedure (time from operation to THA) was 39.3 years (21 to 55).
Conclusions:
The Spitzy operation had good short and long-term effects on hip pain and a 30-year survival (no THA) of 72% of the hips. These results compare favourably with those of PAO and indicate that there is still a place for the shelf procedure in older children and young adults.
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