Jörg Lützner1, Franziska Beyer2, Cornelia Lützner2, Peter Thomas3, Burkhard Summer3. 1. University Center of Orthopaedic, Trauma and Plastic Surgery, University Hospital, TU Dresden, Fetscherst. 74, 01307, Dresden, Germany. Joerg.Luetzner@ukdd.de. 2. University Center of Orthopaedic, Trauma and Plastic Surgery, University Hospital, TU Dresden, Fetscherst. 74, 01307, Dresden, Germany. 3. Department of Dermatology und Allergology, Ludwig-Maximilias-University, Frauenlobstraße 9-11, 80337, Munich, Germany.
Abstract
PURPOSE: Allergy against implant materials is discussed controversially and still not fully understood. Despite these controversies, a relevant number of patients receive hypoallergenic knee implants. The aim of this study was to compare a new coating system with the standard implant in total knee arthroplasty (TKA). Additionally, the influence of proinflammatory cytokines on patient-reported outcome measures (PROMs) was investigated. METHODS: 120 patients without known metal allergy and without previous metal implants were included. The patients were randomized to receive a coated or standard TKA of the same knee system. 105 patients completed the 5 year follow-up. Patient-reported outcome measures (PROMs) including knee function (Oxford Knee Score, OKS), quality of life (SF36) and UCLA activity scale were assessed. Additionally, several cytokines with a possible role in implant allergy were measured in patient`s serum (IL-1beta, IL-5, IL-6, IL-8, IL-10, IP-10, IFN γ, TNF α). Group comparison was performed using Mann-Whitney U test for continuous values and chi-square test for categorical values. RESULTS: There were no differences in PROMs between both groups at any follow-up. The majority of patients demonstrated no elevation of the measured blood cytokines. The blood cytokine pattern after 5 years demonstrated no differences between study groups. There was a significant association between elevated IL-8 values and worse results in the overall OKS (p = 0.041), the OKS function component (p = 0.004), the UCLA activity scale (p = 0.007) and the physical component of SF36 (p = 0.001). CONCLUSION: There were no problems with the new coating during mid-term follow-up and no differences in PROMs between coated and standard TKA. Patients with an increased inflammatory response demonstrated worse functional results, regardless of the implant. LEVEL OF EVIDENCE: I. CLINICAL TRIAL REGISTRATION: The study protocol was registered in the US National Institutes of Health's database ( http://www.clinicaltrials.gov ) registry under NCT00862511.
PURPOSE: Allergy against implant materials is discussed controversially and still not fully understood. Despite these controversies, a relevant number of patients receive hypoallergenic knee implants. The aim of this study was to compare a new coating system with the standard implant in total knee arthroplasty (TKA). Additionally, the influence of proinflammatory cytokines on patient-reported outcome measures (PROMs) was investigated. METHODS: 120 patients without known metal allergy and without previous metal implants were included. The patients were randomized to receive a coated or standard TKA of the same knee system. 105 patients completed the 5 year follow-up. Patient-reported outcome measures (PROMs) including knee function (Oxford Knee Score, OKS), quality of life (SF36) and UCLA activity scale were assessed. Additionally, several cytokines with a possible role in implant allergy were measured in patient`s serum (IL-1beta, IL-5, IL-6, IL-8, IL-10, IP-10, IFN γ, TNF α). Group comparison was performed using Mann-Whitney U test for continuous values and chi-square test for categorical values. RESULTS: There were no differences in PROMs between both groups at any follow-up. The majority of patients demonstrated no elevation of the measured blood cytokines. The blood cytokine pattern after 5 years demonstrated no differences between study groups. There was a significant association between elevated IL-8 values and worse results in the overall OKS (p = 0.041), the OKS function component (p = 0.004), the UCLA activity scale (p = 0.007) and the physical component of SF36 (p = 0.001). CONCLUSION: There were no problems with the new coating during mid-term follow-up and no differences in PROMs between coated and standard TKA. Patients with an increased inflammatory response demonstrated worse functional results, regardless of the implant. LEVEL OF EVIDENCE: I. CLINICAL TRIAL REGISTRATION: The study protocol was registered in the US National Institutes of Health's database ( http://www.clinicaltrials.gov ) registry under NCT00862511.
Authors: Maria Herbster; Joachim Döring; Jiri Nohava; Christoph H Lohmann; Thorsten Halle; Jessica Bertrand Journal: J Mech Behav Biomed Mater Date: 2020-08-18
Authors: Mathias C Galetz; Ernst W Fleischmann; Christian H Konrad; Adelheid Schuetz; Uwe Glatzel Journal: J Biomed Mater Res B Appl Biomater Date: 2010-04 Impact factor: 3.368