A pilot study to investigate the combined use of Botulinum toxin type-a and ankle foot orthosis for the treatment of spastic foot in chronic hemiplegic patients.

BACKGROUND

Botulinum toxin is commonly used to treat spastic equinus foot. This treatment seems to improve gait in hemiplegic patients when used alone or combined with an ankle-foot orthosis. However, the nature and effects of this improvement have until now rarely been studied. The aim of this study was to quantify the impact of a Botulinum toxin injection in the triceps surae of hemiplegic patients with equinus foot, used either alone or in combination with an ankle-foot orthosis, on the kinematics and dynamics of the paretic lower limb, and to determine the advantage of combining an ankle-foot orthosis with this pharmacological treatment.

METHODS

Patients were assessed using gait analysis to measure spatio-temporal, kinematic and dynamic parameters of the gait cycle before Botulinum toxin injection and then 3 and 6weeks after injection. Eight chronic hemiplegics following central nervous system lesion were included.

FINDINGS

Botulinum toxin injection led to an increase in velocity, peak ankle dorsiflexion during stance phase, and peak knee flexion during swing phase. It also resulted in an increased peak plantarflexion moment. Use of ankle-foot orthosis led to a specific increase in peak ankle dorsiflexion during swing phase and also increased peak plantarflexion moment.

INTERPRETATION

The results indicate that combined Botulinum toxin injection of the triceps surae and wearing an ankle-foot orthosis is more effective than the use of Botulinum toxin only. Use of an ankle-foot orthosis increases ankle dorsiflexion during the swing phase and does not reduce the benefits gained by the use of Botulinum toxin in stance phase.