Sagittal stability and implant design affect patient reported outcomes following total knee arthroplasty.

Abstract Aims Joint stability is one of the goals of any joint replacement. The contribution of prosthesis design to sagittal stability in total knee arthroplasty (TKA) has emerged as an area of interest. The purpose of this study was to evaluate the sagittal stability of four prosthesis types and determine the effect on patient reported outcome measures (PROM). Methods A matched-cohort cross-sectional study was performed on 60 patients following TKA at 1-year follow-up. Three surgeons performed 10 medially stabilized (MS) TKA and 10 non-MS TKA. Sagittal stability was assessed by a blinded observer using a KT-1000 arthrometer, Lachman’s test and the anterior drawer test. PROMs (Oxford, KOOS, WOMAC, FJS) and visual analogue scale (VAS) assessed function and satisfaction. Results MS TKA had significantly decreased translation on KT-1000 and improved stability compared to non-MS (p Discussion The MS TKA had significantly greater sagittal stability, improved PROMs and satisfaction compared to non-MS TKA. Independent of prosthesis design, patients with greater sagittal stability demonstrated improved PROMs.