Movement Pattern Biofeedback Training Improves Short- and Long-Term Limb Loading Mechanics During Step Descent After Total Knee Arthroplasty: Secondary Analysis of a Randomized Controlled Trial

OBJECTIVE: To evaluate the effects of a 10-week movement pattern biofeedback training intervention (MOVE) on limb-loading mechanics during step descent following primary unilateral TKA, compared to a control group. DESIGN: Exploratory secondary analysis of a randomized controlled trial. METHODS: One hundred thirty-eight participants were assessed preoperatively, 10 weeks, 6 months, and 2 years after TKA. Three-dimensional motion data were collected during performance of a step-down task. Repeated measures analyses of covariance were used to determine between-group differences in lead limb loading rate and trailing limb peak knee extension moment of both the surgical and non-surgical limbs, controlling for baseline function and sex. Multivariate linear regression models were developed to explore factors associated with loading rate of the leading, non-surgical limb at each follow-up timepoint, controlling for sex and intervention group. RESULTS: The MOVE group displayed smaller surgical and non-surgical limb loading rate 10-weeks and 6-months post-TKA respectively, compared to control (p<.05). No between-group differences in peak knee extension moment were observed at any timepoint. Greater 10-week non-surgical limb loading rate was associated with greater preoperative non-surgical limb loading rate and lower surgical trailing limb peak knee extension moment (p<.05). Greater 6-month non-surgical limb loading rate was associated with greater preoperative non-surgical limb loading rate (p<.05). Greater 2-year non-surgical limb loading rate was associated with greater preoperative non-surgical limb loading rate and lower surgical trailing limb peak knee extension moment (p<.05). CONCLUSION: A novel movement pattern biofeedback training intervention reduced contralateral limb loading rates during step descent after TKA. Variability in loading mechanics at long-term follow up was consistently explained by preoperative movement patterns.