Abstract
Introduction: While an increasing number of authors have reported on the long-term results of primary alumina total hip arthroplasty (THA) [1], strategies for revising a ceramic-on-ceramic THA are debated in the literature. According to some authors [2], the reimplantation of a ceramic head on a well-fixed femoral stem is inadvisable, as it may lead to a fracture of the newly implanted head. The aim of the present study was to evaluate the incidence of this specific issue, and to report on the clinical and radiological results of the revised hips.
Methods: Between January 1977 and December 2005, 138 consecutive alumina-alumina revision hip arthroplasties were performed in 127 patients. There were 79 women (62.2%) and 48 men (37.8%), with an average age of 67 years (range, 32–91 years). Among these, an isolated acetabular revision was performed in 108 cases. The reason for revision was aseptic loosening of the acetabular component in 98 hips, pain in 7, fracture of an alumina liner in 2, and recurrent dislocation in 1. The revised socket was a cemented alumina in 56 hips, a threaded screw-in titanium with an alumina core in 34, a pressfit titanium with an alumina core in 11, and bulk alumina in 7. Acetabular bone stock losses were classified according to the AAOS system. Most of the hips had a contained type II defect (86%). In all cases, the femoral stem was left in place and the acetabular component alone was revised. At the time of revision surgery, an aluminaalumina combination was implanted in 27 hips, an aluminapolyethylene combination in 56, a metal-poly-ethylene combination in 15, and a zirconia-polyethylene in 10. Overall, a ceramic head was reimplanted on a used femoral taper in 59 cases. Acetabular reconstruction with allografts supported with the Kerboull acetabular reinforcement device was performed in 31% of the hips.
Results: The mean follow-up period was 78 ± 37 months. Thirteen patients (15 hips) died a mean 37 months after surgery. Sixteen patients were lost to follow-up. Postoperatively, five hips had a recurrent dislocation, 2 a deep infection, 9 a trochanteric nonunion (21,3%), 6 a transient nerve palsy. 18 hips required a re-revision surgery, 12 of which for aseptic loosening of the acetabular component. Among the 59 ceramic heads implanted on a well-fixed stem, no fracture of the head occurred at a mean 81 months follow-up. Of the original 108 hips, 77 were available for clinical evaluation and 75 for radiological evaluation at least 2 years after surgery. The mean Merle d’Aubigné score increased from 10.1 ± 2.1 to 16.7 ± 1.1 at the latest follow-up (p< 0.001). Forty-five hips were graded excellent or very good (60%), 26 good (34,6%), 3 fair (4%), and 1 poor (1.3%). When revision for aseptic loosening was considered as a failure, the overall survival rate at 8 years was 96.3 ± 1.8%.
Discussion & Conclusions: In the present study, aseptic loosening of the acetabular component was the main reason for revision surgery. Osteolysis around ceramic implants was moderate and was related to the migration of the socket. Among the ceramic heads implanted on a used titanium trunnion, no fracture was observed. This approach is possible, in so far as careful inspection does not show any major imperfection of the morse taper [3]. As for other bearing surfaces, the management of aseptic loosening of al-al prostheses is based on the amount of osteolysis around the loosened socket.
Correspondence should be addressed to Diane Przepiorski at ISTA, PO Box 6564, Auburn, CA 95604, USA. Phone: +1 916-454-9884; Fax: +1 916-454-9882; E-mail: ista@pacbell.net
References:
1 Hannouche D, Hamadouche M, Nizard R, Bizot P, Meunier A, Sedel L. Clin Orthop (2005) 430: 62–71. Google Scholar
2 Pulliam IT, Trousdale RT. (1997) J Bone Joint Surg Am79 (1): 118–21. Google Scholar
3 Willmann G. Clin Orthop, (2000) 379: 22–8. Google Scholar
