Gait analysis and other functional parameters in foot dystonia following botulinum toxin A injection

Abstract

Foot dystonia (FD) is a movement disorder characterised by sustained or intermittent muscle contractions causing abnormal, often repetitive movements resulting in pain, spasm and difficulty in walking. The most effective treatment for FD is botulinum toxin injection. The spatiotemporal gait analysis in Gait Rite is well validated and may help clinicians to record the outcomes more objectively. In this paper, we discuss the spatiotemporal gait parameters in FD pre- and post-botulinum toxin injection along with other lower limb functional outcomes. Fourteen (14) adult patients with FD were assessed in the multidisciplinary spasticity clinic pre-and post-injection of botulinum toxin. We conducted gait analysis in the Gait rite system besides recording Fan Marsden Dystonia Scale (FMDS), Visual Analog Scale (VAS) of pain, Berg Balance Score (BBS), Unified Parkinson's Disease Rating Scale - Lower Limb Score (UPDRSLL), Timed Up and Go (TUG) test and the Goal Attainment Scale (GAS). We used the random effects panel data estimators in Stata to examine the difference from before the intervention to after to assess whether there was significant change in gait parameters. In all models the test for the time effect was adjusted for age, sex, and side (left or right). We found that stride length increased significantly in both the affected ( P = 0.021) and unaffected leg (0.010) after treatment, and that the improvement in stride length was roughly the same in each leg. Similar results were found for step length ( P = 0.021) with improvement in the step length differential ( P = 0.016). The improvement in the lower limb functional outcomes were also significant (FMDS, P < 0.001, VAS, P < 0.001, TUG, P < 0.001, BBG, P = 0.001, UPDRSLL, P < 0.001, GAS, P < 0.001, GV, P = 028) except Cadence, P = 0.367. BT is effective in improving walking in foot dystonia as evidenced through gait analysis and improved lower limb functional outcomes.