Biomechanical mechanisms of early gait training on knee cartilage degeneration after anterior cruciate ligament reconstruction: a study protocol.

OBJECTIVE

The primary objective of this study is to investigate the effects and biomechanical mechanisms of early gait retraining (GRT) on knee cartilage degeneration following anterior cruciate ligament reconstruction (ACLR).

METHODS

This study is a single-blind, parallel-group randomized controlled trial. A total of 60 participants scheduled for primary unilateral ACLR will be recruited and randomly allocated to either the experimental group (conventional rehabilitation plus gait retraining) or the control group (conventional rehabilitation only). Gait retraining will commence at 3 weeks post-surgery, lasting for 6 weeks with a frequency of 2-3 sessions per week, each lasting 15-20 min. Data will be collected at baseline (pre-intervention) and at 3 months, 6 months, 1 year, and 2 years postoperatively. Assessment will include three-dimensional gait analysis, surface electromyography (sEMG), isokinetic muscle strength testing, functional magnetic resonance imaging (fMRI), Y-balance test, single-leg hop test, the International Knee Documentation Committee (IKDC) subjective knee evaluation form, Lysholm knee score, and Tegner activity scale. The primary outcome measure is the peak knee flexion moment during walking. Secondary outcomes include cartilage T1ρ/T2 values, muscle activation patterns, and subjective functional scores. A repeated-measures analysis of variance (ANOVA) will be used to evaluate the intervention effects on the outcome measures.

RESULTS

Not applicable.

CONCLUSION

Early gait retraining using a lower-body positive pressure (anti-gravity) treadmill after ACLR is hypothesized to significantly improve postoperative gait biomechanics. Furthermore, early GRT may optimize standard rehabilitation protocols, potentially preventing or delaying cartilage degeneration. This approach holds clinical significance for restoring normal gait and preventing secondary injuries in individuals with sports-related injuries.

CLINICAL TRIAL REGISTRATION: https:register.clinicaltrials.gov, identifier NCT06368544.