Abstract
The study reviews 24 patients with 27 total hip arthroplasties in which an acetabular reinforcement ring with hook was used for primary total hip arthroplasty (THA) due to underlying hip dysplasia.
There were 19 female and 5 male patients with a mean age of 50.6 years (31 to 70) at the time of surgery. A bulk autograft for acetabular reconstruction was used in four cases with Crowe Type III and IV dysplasia. In eight cases cancellous bone alone was used to fill the gap between the reinforcement ring and the acetabulum. All patients had a polyethylene cup cemented into the ring and 22 cases had a straight Müller CDH stem cemented into the shaft.
Mean follow-up was 10.7 years (range: 8.1 to 12.7). No clinical or radiographic signs of loosening of the reinforcement ring were found in 24 (88.9 %) of the 27 THAs. Two revisions (7.4%) were performed for aseptic loosening and one acetabular component had radiographic signs of loosening. The Merle D`Aubigné score had increased from 7 to 15 points.
The acetabular reinforcement ring continues to have favourable results in this specific patient group and may also prevent graft resorption and cup migration.
The abstracts were prepared by David P. Davlin. Correspondence should be addressed to him at the Orthopedic Clinic Bulovka, Budínova 2, 18081 Prague 8, Czech Republic.