Late dislocations after total hip arthroplasty: Is the bearing a factor?

• Published in: The Journal of arthroplasty Vol. 32; no. 9; pp. 2852 - 2856
• Main Authors: Shah, Siddharth M., MS (Orth), Walter, William L., FRACS (Orth), PhD, Tai, Stephen, FRCS (Tr & Orth), Lorimer, Michelle, BSc (Maths & Comp Sc), deSteiger, Richard, FRACS (Orth)
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.09.2017
• Subjects: Arthroplasty, Replacement, Hip - adverse effects; bearing surface; Biocompatible Materials; ceramic-on-ceramic; Ceramics; cross-linked polyethylene; Hip Dislocation - etiology; Hip Prosthesis - adverse effects; Humans; late dislocation; Male; Metals; Orthopedics; Polyethylene; Prosthesis Design - adverse effects; Prosthesis Failure; Registries; Reoperation; total hip arthroplasty; XLPE; metal-on-cross linked polyethylene; MoXLPE; CPR; osteoarthritis; metal-on-polyethylene; MoM; HR; hazards ratio; THA; metal-on-metal; MoP; OA; cross- linked polyethylene; ARMD; Australian Orthopaedic Association National Joint Replacement Registry; ceramic-on-cross linked polyethylene; cross linked polyethylene; late dislocation; adverse reaction to metal debris; CI; bearing surface; CoXLPE; total hip arthroplasty; AOANJRR; CoC; ceramic-on-ceramic; confidence interval; cumulative percentage revision; cross-linked polyethylene
• ISSN: 0883-5403; 1532-8406
• DOI: 10.1016/j.arth.2017.04.037

Abstract Background Dislocation is a leading cause of revision after primary total hip arthroplasty (THA). While more common in the first few years post procedure, dislocation can occur at any time. This study investigated the difference in late dislocation in ceramic on ceramic bearings compared to metal on polyethylene and ceramic on polyethylene bearings in THA. Methods Data was used from the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) and the cumulative percent revision (CPR) for dislocation was estimated using the Kaplan-Meier method for the different bearing surfaces. There were 192,275 THA included in the study with 101,915 metal on cross linked polyethylene (MoXLPE), 30,256 ceramic on cross linked polyethylene (CoXLPE), and 60,104 ceramic on ceramic (CoC). Results The CPR for dislocation at 13 years for MoXLPE, CoXLPE and CoC groups was 1.2 (95% CI 1.1- 1.3), 1.0 (95% CI 0.7- 1.4) and 0.9 (95% CI 0.8-1.1) respectively. There was an increased risk of revision for dislocation for MoXLPE compared to CoXLPE and CoC. When stratified for head size there was no difference in the risk of revision for dislocation between MoXLPE, CoXLPE and CoC in the 28mm and 32mm head sizes. With head sizes 36mm, MoXLPE had a higher rate of dislocation compared to other materials. Conclusion Bearing surface has little impact on revision for dislocation.