Improved outcomes in patients with positive metal sensitivity following revision total knee arthroplasty

Abstract

Background Metal sensitivity as a cause for painful joint replacement has become increasingly prevalent; however, there is a lack of reported clinical outcome data from total knee arthroplasty patients with metal allergies. The purpose of this study was to determine whether patients presenting with a painful total knee arthroplasty with a positive metal sensitivity have improved outcomes following revision to a hypoallergenic implant. Methods A retrospective review was conducted for patients that underwent a revision total knee arthroplasty after metal sensitivity testing over a 3-year period from January 1, 2015, to December 31, 2017. Based on the results of sensitivity testing, patients underwent revision total knee arthroplasty to a hypoallergenic component or a standard component. Following revision, patients returned to the clinic at an interval of 6 weeks, 5 months, and 12 months for functional, pain, and satisfaction assessment. Outcomes were compared within and between sensitivity groups. Results Of the included patients, 78.3% (39/46) were positive for metal sensitivity. The most common metal sensitivity was to nickel (79.5%, 32/39). Both non-reactive and reactive patients significantly improved in range of motion after revision arthroplasty. The reactive group saw a 37.8% decrease in pain at 6 weeks post-revision ( p < 0.001) Whereas, the non-reactive group only saw a moderate, non-significant improvement in pain reduction at 6 weeks post-revision (27.0%; p = 0.29). Frequency of pain experienced did not vary significantly between groups. Maximum metal lymphocyte transformation test (LTT) sensitivity score did not correlate with pain level at the time of revision ( R 2 = 0.02, p = 0.38) or percent improvement after revision ( R 2 = 0.001, p = 0.81). Overall, all patients reported being very satisfied after revision total knee arthroplasty; there was no difference between positive and negative sensitivity groups ( W = 62, p = 0.89). Conclusions Patients presenting with a painful knee arthroplasty and positive metal LTT have improved pain scores, walking function, and range of motion following revision to a hypoallergenic component. This study also provides a treatment algorithm for patients presenting with a painful knee replacement, in order to provide effective and timely diagnosis and management. Electronic supplementary material The online version of this article (10.1186/s13018-019-1228-4) contains supplementary material, which is available to authorized users.

Memory T helper cells identify patients with nickel, cobalt, and chromium metal allergy

“…LPT has been tested with varying success to detect sensitization to implant materials. [23][24][25] We speculate that analysing Th mem hi cells could improve the detection of circulating implantspecific Th cells. However, to further improve implant-reactive cells' detection, valuable knowledge of the chemokine profile of implant metal-reactive cells is still needed.…”

Metal allergy in primary and revision total knee arthroplasty

“…Six case series with 128 patients reported on their findings in patients with painful TKA and metal allergy, infection, and other causes of pain excluded, who underwent rTKA with hypoallergenic components and reported overall improvements in clinical outcomes and patients’ symptoms at short term follow-up. 36 - 41 Interestingly, there were no differences in outcomes between patients with positive or negative patch testing/LTT. 37 Histologically, intraoperative specimens showed fibrosis and lymphocytic infiltration, but no correlation with LTT testing, 38 and thickened synovium with either a predominantly lymphocytic or histiocytic monocellular response was also reported.…”

Osteoimmunology: A Current Update of the Interplay Between Bone and the Immune System

“…For these patients, careful selection of materials used is vital to prevent unnecessary revision procedures. A retrospective study by Zondervan et al in 2019 presented patients with all-around improved testing scores (pain, walking quality, Range of motion) when revised to a hypoallergic component in total knee arthroplasty (229). Some of these patients may have avoided a secondary operation if tested beforehand and treated accordingly.…”