OUTCOME OF CERAMIC-CERAMIC TOTAL HIP ARTHROPLASTY AT TWO TO TEN YEARS IN PATIENTS WITH DEVELOPMENTAL DYSPLASIA OF THE HIP

Abstract

Total hip arthroplasty (THA) in patients with developmental dysplasia of the hip (DDH) has been associated with increased rates of complications and revision. Hip instability and wear-induced osteolysis are among the more common and serious of these problems. The current investigation prospectively assessed the clinical results and the survivorship of patients with DDH treated by alumina ceramic-ceramic THA.

We investigated 164 consecutive hips in 147 patients with DDH. Twenty-five hips (15%) had prior surgery to improve acetabular coverage, 108 hips (66%) were classified as Crowe type I, 21 (13%) as type II, and 10 (6%) as type III. All patients had an uncemented titanium acetabular component with a flush mounted alumina ceramic-ceramic bearing and were treated between 1997 and 2006. The mean age at operation was 48.5 ± 12.2 years (range, 18–75 years). The preoperative Merle d’Aubigné score was 11.3 ± 1.6 (6–15). Ninety-four hips (57%) were replaced with the use of surgical navigation for acetabular component positioning. The mean cup diameter was 51.2 ± 3.9 mm (46–60 mm). Seventy-seven (47%) bearings were 28mm and 87 (53%) bearings were 32mm.

At a mean follow-up of 4.5 ± 2.3 years (2–10 years), the mean Merle d’Aubigné score was 17.5 ± 1.2 (14–18). There were no cases of osteolysis or dislocation. There was one reoperation of an early displaced cup. In addition, there was one calcar crack that was cerclaged, one intraoperative trochanteric fracture also repaired at surgery. No patient complained of squeaking. Ninety-four patients with 100 hips (61%) completed a questionnaire specifically concerning squeaking. None of these patients reported on squeaking either. The 10-year Kaplan Meier survivorship of the implants (revision of any component for any reason) was 99.1% (95% confidence interval 98.0–100%).

Results of ceramic-ceramic THA in young patients with low to middle graded DDH after two to ten year follow-up are promising with no radiographic signs of osteolysis or dislocation.