1. Introduction
Botulinum toxin type A (BoNT-A) represents the gold standard therapy for focal spasticity and related disorders also in acquired brain injury including stroke. Since 1989, the effectiveness of BoNT-A in reducing poststroke spasticity showed reversibility and low prevalence of complications [1], obtaining the approval of U.S. Food and Drug Administration for upper limb spasticity after stroke in 2010. In the following years, many studies have been published demonstrating its safety and effectiveness [2,3]. However, the role of BoNT-A in the management of poststroke spasticity has been modified, changing from muscle chemodenervation (nerve block) to become an useful tool for improving limb posture, applying splint, consenting hygiene, standing, and walking in patients with spastic equino-varus foot deformities with also improvement joint range of motion and muscle extensibility or reduction of spasticity-related pain.
The correct evaluation of the patient to be injected is necessary to increase the efficacy of BoNT-A considering that there is a high response for improving passive function, but controversy also exists about the improvement in motor function relative to the improvement of spasticity. There are proposals on dosages, injection techniques, patient selection, and outcome measures, but a consensus about the employment of adjunctive therapies after the BoNT-A injection, considered necessary to increase the effect on spasticity reduction, has not been reached, considering the time to start, the duration of adjunctive therapies, and the type of rehabilitation procedures [4]. So, at present, the injection sites, the choice of muscles, the dosage, the dilution, and the rehabilitation programs after BoNT-A treatment are often identified by injector’s decision-making without specialized training.
BoNT-A has clearly been recommended as first-line treatment for focal spasticity by several European consensus statements and the American Academy of Neurology [4,5] and current guidelines suggested the employment of a dose up to 600 units (U) of onabotulinumtoxinA (Botox®, Allergan, Inc., Irvine, CA, USA) and incobotulinumtoxinA (Xeomin®, Merz Pharmaceuticals GmbH, Frankfurt, Germany) or up to 1500 U of abobotulinumtoxinA (Dysport®, Ipsen, Slough, UK/Galderma, Paris, France) per injection session to treat spasticity after stroke [5]. However, in recent years, higher doses have been used, especially in case of upper and lower limb severe spasticity considering the low prevalence of complications and the reversibility of the BoNT-A [6,7]. The possibility to employ high doses is strictly related to the precision of the injection. A correct muscle identification with instrumental guide (i.e. electrical stimulation or ultrasonography) may reduce the spread of the toxins to the nearby tissues and the risk of adverse effects.
TBI Rehabilitation 