We report a systematic review and meta-analysis of the peer-reviewed literature focusing on metal sensitivity testing in patients undergoing total joint replacement (TJR). Our purpose was to assess the risk of developing metal hypersensitivity post-operatively and its relationship with outcome and to investigate the advantages of performing hypersensitivity testing.
We undertook a comprehensive search of the citations quoted in PubMed and EMBASE: 22 articles (comprising 3634 patients) met the inclusion criteria. The frequency of positive tests increased after TJR, especially in patients with implant failure or a metal-on-metal coupling. The probability of developing a metal allergy was higher post-operatively (odds ratio (OR) 1.52 (95% confidence interval (CI) 1.06 to 2.31)), and the risk was further increased when failed implants were compared with stable TJRs (OR 2.76 (95% CI 1.14 to 6.70)).
Hypersensitivity testing was not able to discriminate between stable and failed TJRs, as its predictive value was not statistically proven. However, it is generally thought that hypersensitivity testing should be performed in patients with a history of metal allergy and in failed TJRs, especially with metal-on-metal implants and when the cause of the loosening is doubtful.
- Total joint arthroplasty
- Metal hypersensitivity
- Hypersensitivity testing
- Systematic review
The authors thank Dr E. Pignotti for assistance in the statistical management of the data and Ms L. Scioscia for assistance in the editorial management of the manuscript.
No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article.
Supplementary material. Forest plots showing the risk of metal allergy pre- and post-operatively in patients who have undergone joint replacement are available with the electronic version of this article on our website www.bjj.boneandjoint.org.uk
- Received August 12, 2011.
- Accepted April 24, 2012.
- ©2012 British Editorial Society of Bone and Joint Surgery