Columbus® computer navigated total knee arthroplasty: Gap balancing versus measured resection

The aim of this study was to compare the medium term functional outcome and patient satisfaction of gap balanced (GB) with measured resection (MR) total knee arthroplasty (TKA) using computer navigation.

A cohort of 144 consecutive computer navigated TKA were retrospectively identified from an arthroplasty database. Functional assessment using the Oxford Knee Score (OKS) and patient satisfaction were obtained from 113 patients at a mean follow-up of 5.4 (range four to seven) years. There were 44 patients in the GB group and 69 patients in the MR group.

The mean OKS for the GB group was 36.9 (SD 9.2) and for the MR was 33.6 (SD 9.8), with a difference of 3.3 (95% CI 0.3 to 6.3) points, which was statistically significant (p = 0.01). Linear regression analysis confirmed the independent effect of surgical technique when adjusting for confounding factors and surgeon, with the GB group achieving a greater post-operative OKS (R² = 0.39, 3.0 points, 95% CI 1.2 to 4.8, p = 0.001). There was a greater rate of patient satisfaction in the GB group (88.6%, n = 39/44) compared to the MR group (81.1%, n = 56/69), but this was not statistically significant (odds ratio 1.8, 95% CI 0.6 to 5.5, p = 0.31).

Computer navigated Columbus® TKA using a GB technique results in a statistically significantly greater functional outcome but no significant difference in patient satisfaction in the medium term compared to patients undergoing a MR technique.