Emerging Role of Visual Biofeedback in Rehabilitation Following ACL Reconstruction

Following anterior cruciate ligament reconstruction (ACLR), neuromuscular deficits such as impaired proprioception, altered muscle activation timing, and inter-limb loading asymmetries commonly persist and may increase the risk of ACL reinjury. Visual biofeedback has been widely used to remediate these deficits by providing task-relevant information to reduce high-risk kinematic and kinetic deviations. This narrative review synthesizes clinical applications of visual biofeedback following ACLR across three domains: (1) balance and postural control, (2) quadriceps strength and inter-limb loading symmetry, (3) landing/cutting mechanics related to reinjury risk. Evidence indicates that visual biofeedback improves postural stability and joint position sense, and it can enhance engagement with balance tasks. During weight-bearing exercise, real-time displays of vertical ground reaction force (vGRF) or center of pressure (COP) reduce loading asymmetry and may facilitate quadriceps recruitment in the surgical limb. Visual biofeedback also reduces knee abduction moment and valgus angle, and improves vGRF symmetry during landing or cutting. However, squat-based visual biofeedback does not improve peak knee extension moment symmetry during landing, indicating limited transfer of squat-based visual biofeedback to landing mechanics. These findings show that visual biofeedback can help improve deficits associated with post-ACLR when the feedback variable and training task are aligned with the intended clinical outcome. Future work, including task-specific visual biofeedback protocols that incorporate jump landing and cutting, appears necessary to facilitate correction of inter-limb loading asymmetry during high-demand tasks following ACLR.