Increased inflammatory response is associated with less favorable functional results 5 years after total knee arthroplasty.

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.

• Authors: Jörg Lützner, Franziska Beyer, Cornelia Lützner, Peter Thomas, Burkhard Summer
• Journal: Knee surgery, sports traumatology, arthroscopy : official journal of the ESSKA (Knee Surg Sports Traumatol Arthrosc) Vol. 31 Issue 4 Pg. 1316-1322 (Apr 2023) ISSN: 1433-7347 [Electronic] Germany
• PMID: 35147719 (Publication Type: Randomized Controlled Trial, Journal Article)
• Copyright: © 2022. The Author(s).

Chemical References

• Interleukin-8
• Cytokines

Topics

• Humans
• Arthroplasty, Replacement, Knee (adverse effects, methods)
• Quality of Life
• Interleukin-8
• Knee Prosthesis (adverse effects)
• Knee Joint (surgery)
• Osteoarthritis, Knee
• Hypersensitivity (etiology)
• Cytokines
• Treatment Outcome
• Patient Reported Outcome Measures