Limited evidence examining visual feedback in rehabilitation for generalised knee pain: a scoping review and call for further research

Chronic knee pain is a common source of disability, affecting approximately 20%–40% of adults. Conservative management, particularly physical therapy, is the gold standard for treating generalised knee pain (GKP) and patellofemoral pain (PFP). Current clinical practice guidelines (CPGs) recommend interventions that improve strength and neuromuscular control to treat PFP, but evidence examining visual feedback (VF) is lacking. This scoping review aims to evaluate the impact of VF during closed kinetic chain exercises on pain and biomechanics in individuals with GKP or PFP. A comprehensive search was conducted across six databases for clinical trials published between 2009 and 2024. Eligible studies included adults aged 18–65 years with GKP or PFP, using visual or augmented feedback during closed chain exercises. Outcomes for pain and biomechanical changes were extracted and presented in narrative form. VF was found to reduce joint forces during squatting in subjects with PFP. Changes in joint angles while squatting with VF were inconsistent across two studies. Motor control combined with strengthening showed no clinical improvements except a small decrease in trunk lean. VF showed significant changes in muscle activation for the vastus lateralis and vastus medialis muscles. The limited and inconsistent evidence prevents clear conclusions. Current evidence for VF does suggest changes in joint angles, forces, muscle activity and function. However, more rigorous studies are needed to guide clinical use and confirm the effects of VF when managing knee pain.