Clinical and radiological results of a stemmed medial pivot revision implant in aseptic total knee revision arthroplasty

Abstract

Background: Constraint choice in revision total knee arthroplasty depends on the stability of the collateral ligaments and on the severity of bone loss, but the least degree of constraint necessary is recommended. The purpose of this retrospective matched-paired study was to compare clinical results, radiographic outcome and the survival of a stemmed medial pivot revision implant in aseptic revision TKA vs. medial pivot implant in primary TKA. Methods: Records were reviewed for 69 cases of aseptic revision TKA using Advance® Medial Pivot Stemmed Revision Knee system between 2002 and 2016. These patients were then matched in a 1:2 ratio control group of patients who received a primary TKA with Advance® Medial Pivot system. American Knee Society Score and Visual Analogue Scale pain score were recorded. Alignment, loosening, and incidence of radiolucent lines were evaluated on X-rays. Implant survival was assessed by Kaplan-Meier survival analysis. Results: The primary TKA group had significant superior AKSS clinical and functional score at baseline (52.3 and 68.2 points, respectively) and at last follow up (84.6 and 68.6 points) compared with the revision TKA group (47.9 and 40.9 points; 78.4 and 59.9 points; P b 0.05). No significant difference was observed in the mean change from baseline to last follow up of AKSS score between the two groups (P N 0.05). Radiographical outcome and implant survival were similar in the two groups (P N 0.05). Conclusion: The authors support the use of this revision system in knees with collateral ligaments competence and mild-to-moderate bone defect.