PROSPECTIVE RANDOMISED MULTI-CENTRIC EVALUATION OF COMPUTER-ASSISTED TKR

Abstract

To prospectively evaluate the accuracy as well as patient outcome of computer-assisted total knee replacement in a multi-centric randomised study.

Two hundred and ninety-five patients in six European centers were randomised between two groups: One hundred and forty-seven in the conventional surgery group and one hundred and forty-eight in the computer assisted surgery. Radiological as well as clinical data (SF-36 and KSS scores) were collected preoperatively as well as six weeks and six months postoperatively. A multilevel mixed-effects linear regression for nested variable with random-effects was used to estimate the effect of the independent variable (type of surgery: conventional surgery vs computer assisted surgery) on each of the dependent variables at six weeks and six months post-operatively.

Mechanical axis was statistically better in the navigation group at six weeks (p=0,01) and six months (p=0,04). Similar results are found for the femoral component at six months (p=0,001). At six months, there were statistically greater improvements in the following SF-36 scales for the computer assisted group: bodily pain (p=0,03), role emotional (p=0,03), mental health (p< 0,001), physical health dimension (p=0,01), mental health dimension (p=0,005) and global SF36 score (p=0,002). While a difference in operating time was noted (p< 10-5), the blood losses where similar for both groups (p=0.8).

Computer assisted surgery improves the accuracy in total knee arthroplasty, especially for the mechanical axis and the femoral component orientation. These improvements result in better quality of life for the patient at six months postoperatively. Level of Evidence: I – High-quality randomised controlled trial with statistically significant difference.