Changes in Gait Kinematics with Continuous Intrathecal Baclofen Infusion for Spasticity After Acquired Brain Injury: A Comparison of Implanted and Non-Implanted Cohorts

Abstract

Background

Although several studies have examined gait changes associated with continuous intrathecal baclofen (CITB) infusion for spasticity in ambulatory patients with acquired brain injury (ABI), none has included a control group.

Objective

To assess long-term changes in gait kinematics associated with CITB infusion for post-ABI spasticity.

Methods

Forty-three consecutive ABI patients underwent gait evaluations during an ITB bolus trial, with follow-up gait data available in 17 pump recipients (re-evaluated 24 ± 17 months after implantation, dose range 95–590 µg/day) and 8 non-recipients (re-evaluated 30 ± 19 months after screening). Temporospatial gait parameters and lower extremity joint range of motion (ROM) were analyzed.

Results

Changes in temporospatial gait parameters from baseline to follow-up did not differ significantly between pump recipients and non-recipients. Likewise, there were no significant between-group differences in changes in ROM over time except for a 7.5° increase in more-affected (MA) knee ROM during swing in pump recipients, compared with a 2.4° decrease in non-recipients (ANOVA group×time interaction, P = 0.027). Secondary analyses showed that baseline average Ashworth score in the MA leg correlated significantly with changes in MA stance time and less-affected initial double support time (r ≥ |0.56|, P ≤ 0.029) in pump recipients only.

Conclusions

The modest improvements in gait kinematics in pump recipients appeared to have limited clinical significance, considering no concurrent improvements in average gait speed and the study limitations. The overall results suggest that gait speed may be useful for goal setting, but it should not be considered the sole measure of CITB efficacy.