Comparison of Two Botox Injection Techniques to Improve Gait

According to our hypothesis, the use of HD-EMG shall allow an accurate localization of the innervations zones of the muscles, offering a better complement to the methodology applied so far to define the botulinum neurotoxin (BoNT) injection site. To achieve that goal, a randomized clinical trial comparing the effectiveness of two guiding methods to define the BoNT injection site in the gastrocnemius muscles will be conducted. One arm will be guided with ultrasonography + localized IZ using anatomical references; while the second arm with ultrasonography + in vivo location of the IZ through HD-EMG. The effectiveness will be evaluated by changes in functional tests and in biomechanical parameters of the gait assessed with a three-dimensional motion analysis system. These outcomes will be measured at baseline (T0), at three (T3w) and six weeks (T6w), post BoNT injection. The differences between sessions will be evaluated as measurements of effectiveness. We expect that greater effectiveness will be found in the group that receives the injection of BoNT, guided by the in vivo location of the IZ.