Treatment of refractory anterior knee pain using botulinum toxin type A (Dysport) injection to the distal vastus lateralis muscle: a randomised placebo controlled crossover trial

Imbalance in quadriceps muscle activation may give rise to anterior knee pain. 24 patients suffering from this aetiology of anterior knee pain were randomized to determine the effect of a botulinum toxin type A (BoNT-A) injection on pain management of this condition and improving quadriceps muscle balance. Results after 12 weeks indicated that BoNT-A-injected patients experienced more significant reductions in anterior knee-specific pain and functional knee pain, and had a better balance between the vastus lateralis and vastus medialis portions of the quadriceps muscle.