Clinical Orthopaedics and Related Research®

, Volume 471, Issue 9, pp 2954–2961

High Prevalence of Adverse Reactions to Metal Debris in Small-headed ASR™ Hips

  • Aleksi Reito
  • Timo Puolakka
  • Petra Elo
  • Jorma Pajamäki
  • Antti Eskelinen
Clinical Research

DOI: 10.1007/s11999-013-3023-6

Cite this article as:
Reito, A., Puolakka, T., Elo, P. et al. Clin Orthop Relat Res (2013) 471: 2954. doi:10.1007/s11999-013-3023-6

Abstract

Background

There has been increasing concern of metal-on-metal (MOM) hip replacements regarding adverse reactions to metal debris. Information regarding prevalence and risk factors for these adverse reactions is scarce.

Questions/purposes

The primary purposes of our study were to determine (1) the prevalence of adverse reactions to metal debris among patients who received small-headed (< 50 mm) Articular Surface Replacement (ASR™) prostheses in hip resurfacing procedures or the ASR™ XL prostheses during THAs at our institution, and (2) the risk factors for adverse reactions to metal debris and if they are different in hip resurfacing replacements compared with THAs?

Methods

Small-headed ASR™ prostheses were used in 482 operations (424 patients) at our institution. After the recall of ASR™ prostheses, we established a systematic screening program to find patients with adverse reactions to metal debris. At a mean of 4.9 years (range, 0.2–8.1 years) postoperatively, 379 patients (435 hips) attended a screening program, which consisted of clinical evaluation, whole blood cobalt and chromium measurements, and cross-sectional imaging.

Results

At followup, 162 hips (34%) have been revised. The majority (85%) were revised owing to causes related to adverse reactions to metal debris. The 7-year survivorship was 51% for the ASR™ hip replacement cohort and 38% for the ASR™ XL THA cohort, respectively. Reduced cup coverage was an independent risk factor for adverse reactions to metal debris in both cohorts. High preoperative ROM, use of the Corail® stem, and female gender were associated with an increased risk of adverse reactions to metal debris only in patients undergoing THA.

Conclusions

Adverse reactions to metal debris are common with small-headed ASR™ prostheses. Risk factors for these adverse reactions differ between hip resurfacing procedures and THAs. Our results suggest a more complicated failure mechanism in THAs than in hip resurfacing procedures.

Level of Evidence

Level IV, diagnostic study. See Guidelines for Authors for a complete description of levels of evidence.

Copyright information

© The Association of Bone and Joint Surgeons® 2013

Authors and Affiliations

  • Aleksi Reito
    • 1
  • Timo Puolakka
    • 1
  • Petra Elo
    • 1
  • Jorma Pajamäki
    • 1
  • Antti Eskelinen
    • 1
  1. 1.Coxa Hospital for Joint ReplacementTampereFinland