Influence of motor imagery training after anterior cruciate ligament reconstruction on kinetic gait parameters

Background: Anterior cruciate ligament reconstruction (ACLR) is a standard surgical procedure to restore knee stability after ACL rupture. It is typically followed by physical therapy over several months. This pilot study evaluates the effect of additional motor imagery training (MIT) on gait parameters after ACLR.Methods: Nine subjects (55% male) with ACLR were randomly split into intervention and control group. Both groups received standard physical therapy, while the intervention group additionally executed a MIT of 15-20 minutes on five days a week for a total of eight weeks. After eight weeks, gait patterns of all subjects were measured. Kinetics were measured with force plates, kinematics with skin markers and infrared cameras. Kinetic and time/space parameters were calculated in post-processing. Left-right symmetry was evaluated with the absolute symmetry index (ASI). In addition, MIT quality was evaluated through a kinaesthetic and visual imagery questionnaire.Results: No significant differences between study groups were found in kinetic gait parameters (p > 0.05). Relevant asymmetries occurred more frequently in the intervention group but were of no statistical significance. Calculated time distance parameters showed no significant differences as well.Discussion: Results suggest that MIT has no valuable effect on kinetic gait parameters. Less frequent occurrences of relevant asymmetries in the control indicate a potential case against the intervention. These preliminary findings correspond with parts of current literature, stating that MIT after ACLR may not significantly support the outcome of rehabilitation. Further research needs to be conducted on MIT after ACLR to predict its effects more accurately.