Motor endplate-targeted botulinum toxin injections of the gracilis muscle in @entity1 with XXXX .

@entity1 @entity508 @entity2653 @entity306
AIM: Intramuscular botulinum toxin-A (BoNT-A) injections reduce @entity508 by blocking neurotransmission at the motor endplate (MEP). The goal of this study was to assess the reduction in @entity508 achieved by injecting BoNT-A at different sites of the gracilis muscle. METHOD: Thirty-four gracilis muscles, in 27 @entity1 (10 females and 17 males, mean age of 8.6y [SD 2.5y]) with @entity306 (unilateral and bilateral, Gross Motor Function Classification System [GMFCS] levels I-IV), were randomly assigned to one of two groups. In one group BoNT-A was injected proximally (at a site 25% of the distance from the pubic tubercle and the medial epicondyle) and in the other it was injected at the MEP zones (half of the dose was administered at 30% of this distance and half at 60%). Spasticity was assessed before and after BoNT-A injection using simultaneous measurements of surface electromyography (sEMG) and angular velocity during passive muscle stretch applied at different velocities. The primary outcome measure included the velocity-dependent change in average root mean square electromyography (RMS-EMG). Secondary outcome was assessed with the Modified Ashworth Scale (MAS) and @entity2653 ( @entity2653 ). RESULTS: Spasticity decreased more in MEP-targeted muscles than in proximally injected muscles, as demonstrated by a larger reduction in average RMS-EMG values (p=0.04), though this difference was not found with the MAS or @entity2653 . INTERPRETATION: The results suggest that BoNT-A injection of the gracilis at sites with a high concentration of MEPs is effective at reducing @entity508 . These preliminary findings should be confirmed by larger studies. In the case of long muscles, such as the gracilis, the injection site is important.
