Evaluating motor end-plate-targeted injections of botulinum toxin type A in a canine model.

Tarsal joint forces were measured in dogs over 70 days following botulinum toxin type A (BTX-A) injections. Three dogs were injected at motor end-plates located by electromyography (EMG), while 3 dogs were similarly injected, but without EMG guidance. Extension forces were significantly (P < 0.05) smaller in limbs injected at motor end-plates than in corresponding limbs on days 14 and 35. There were no significant differences at other times. Using these techniques, EMG end-plate targeting potentiates effects of BTX-A.