Hemiparetic gait and changes in functional performance due to OnabotulinumtoxinA injection to lower limb muscles

• Measurement of temporal spatial gait parameters helps assess function in hemiparetic patients.
• Dynamic EMG is valuable in the selection of muscles in hemiparetic gait.
• Gait parameters showed significant increase in walking velocity and cadence after OnabotA injection to ankle muscles.
• Average of 320 (±107) units of OnabotA injection to selected ankle muscles enhances functional ambulation in hemiparetic gait.

ObjectiveTo review gait alterations and evaluate the effects of OnabotulinumtoxinA on spatiotemporal walking parameters of patients with hemiparetic gait.DesignRetrospective pre- and post-intervention analysis.SettingGait analysis laboratory in a tertiary level rehabilitation hospital.Participants42 patients with hemiparesis. 19 males and 23 females, age 18–78 years were included.InterventionSpatiotemporal parameters collected before and within 4–10 weeks after OnabotA injection to the ankle muscles. Data was recorded at self-selected velocity on a 12 m instrumented walkway. The most common muscles injected were medial and lateral gastrocnemius, soleus and tibialis posterior. Average total OnabotulinumtoxinA dose was 320 ± 107 units.Main outcomeSpatiotemporal parameters of walking assessed before (T0) and within 4–10 weeks post injection (T1). Paired t-test was used to compare pre- and post-intervention data. A sequential Holm–Bonferroni procedure was used to adjust for multiple comparisons and minimize the risk of type I error. Statistical significance was set at p < 0.05.ResultsStatistically significant increases were seen for walking velocity (20%) (T0 = 0.40 ± 0.26 m/s and T1 = 0.48 ± 0.29 m/s; p = 0.006), and increased cadence (T0 = 63.48 ± 23.93 steps/min, and T1 = 70.88 ± 23.65 steps/min; p = 0.006) following OnabotulinumtoxinA injections.ConclusionThis study demonstrates that injection of OnabotulinumtoxinA 320 units to ankle muscles selected with the aid of dynamic electromyography can significantly increase gait velocity and enhance functional ambulation in adults with hemiparesis due to upper motor neuron syndrome.