Patient-reported outcomes and component rotation in total knee replacement: a prospective, observational study in 498 patients.

OBJECTIVES

To assess the relation between component rotation in total knee replacement and clinical outcomes.

DESIGN

Prospective, observational cohort study.

SETTING

Deventer hospital, Deventer, The Netherlands.

PARTICIPANTS

498 adults aged 18 years and older undergoing total knee replacement.

INTERVENTIONS: Participants underwent Persona posterior stabilised total knee replacement. Femoral and tibial component rotation was measured using low-dose CT scans.

MAIN OUTCOME MEASURES: The primary outcome was the change in Oxford Knee Score from baseline to 1 year, analysed in relation to femoral, tibial and combined component rotation.

RESULTS

Binary logistic regression analysis showed no statistically significant association between femoral component rotation (OR=1.04, 95% CI 0.89 to 1.21, p=0.644), tibial component rotation (OR=0.99, 95% CI 0.94 to 1.03, p=0.467), or combined rotation (OR=0.99, 95% CI 0.95 to 1.03, p=0.552), and achievement of the minimal clinically important difference of 5 points for the 48-point Oxford Knee Score.

CONCLUSIONS

This prospective study of 498 patients undergoing total knee replacement did not provide evidence of a relation between the rotational alignment of total knee arthroplasty components and clinical outcomes. These findings do not support routine evaluation of rotational alignment as a basis for revision surgery in patients with persistent pain in the absence of mechanical problems.

TRIAL REGISTRATION NUMBER: Dutch Trial registry ID: 23362.