Spatiotemporal Gait Analysis and Lower Limb Functioning in Foot Dystonia Treated with Botulinum Toxin.

Foot dystonia (FD) is a disabling condition causing pain, spasm and difficulty in walking. We treated fourteen (14) adult patients experiencing FD with onabotulinum toxin A injection into the dystonic foot muscles. We analyzed the spatiotemporal gait utilizing the GaitRite system pre- and 3 weeks post-botulinum toxin injection along with measuring dystonia by the Fahn⁻Marsden Dystonia Scale (FMDS), pain by the Visual Analog Scale (VAS) and other lower limb functional outcomes such as gait velocity, the Berg Balance Scale (BBS), the Unified Parkinson's Disease Rating Scale⁻Lower Limb Score (UPDRS⁻LL), the Timed Up and Go (TUG) test and the Goal Attainment Scale (GAS). We found that stride length increased significantly in both the affected ( p = 0.02) and unaffected leg ( p = 0.01) after treatment, and the improvement in stride length was roughly the same in each leg. Similar results were found for step length ( p = 0.02) with improvement in the step length differential ( p = 0.01). The improvements in the lower limb functional outcomes were also significant-FMDS, VAS, TUG, and UPDRS⁻LL decreased significantly after treatment (all p < 0.001), and BBS ( p = 0.001), GAS ( p < 0.001) except cadence ( p = 0.37). BT injection improved walking in foot dystonia as evidenced through gait analysis, pain and lower limb functional outcomes. Main study limitations were small sample size and lack of control.