Effects of Botulinum Neurotoxin Type A (BoNT/A) Free of Complexing Proteins in the Spastic Equinovarus Foot

Effects of Botulinum Neurotoxin Type A (BoNT/A) Free of Complexing Proteins in the Spastic Equinovarus Foot

Effects of Repeated Use of Botulinum Neurotoxin Type A (BoNT/A) Free of Complexing Proteins in the Spastic Equinovarus Foot in Stroke Patients: A Randomized Clinical Trial

Clinical randomized clinical trial to assess the effectiveness on walking speed of repeated use of botulinum neurotoxin type A (BoNT/A)in the post-stroke spastic equinovarus foot in three successive infiltrations at 6-month intervals, checking if the sustainability of the effect is greater in incobotulinumtoxin A (Xeomin®) than in onabotulinumtoxinA (Botox®).

Spasticity is present in 38% of patients at six months after stroke. Equinovarus foot, with or without claw toes and striatal foot, is especially common. There is a weak to moderate evidence in favor of the use of botulinum neurotoxin type A (BoNT/A) in the equinovarus foot, stiff-knee and in other patterns that may interfere with gait ability. Specifically, BoNT/A increases walking speed in stroke patients with spastic equinovarus foot. Repeated use of BoNT/A may lead to the appearance of neutralizing antibodies, so its effect may decrease over successive infiltrations. Among the differential characteristics of incobotulinumtoxinA (Xeomin®) there is a reduced inactivated botulinum neurotoxin content and the lack of complexing proteins, which would diminish antigenicity and not suppose a decrease of the effect before successive infiltrations. The objective of this project is to determine the effect on walking speed of repeated use of BoNT/A in post-stroke spinal equinovarus foot in three consecutive injections at 6-month intervals and to investigate whether the sustainability of the effect is greater in incobotulinumtoxinA (Xeomin®) than in onabotulinumtoxinA (Botox®). All patients will receive 200-300 units of BoNT/A (Xeomin ® or Botox ®) that will be distributed according to the individual clinical pattern of spastic equinovarus foot.

Three consecutive injections of 200-300 units of IncobotulinumtoxinA (Xeomin ®) under ultrasound guidance. The IncobotulinumtoxinA will be distributed according to the individual clinical pattern of spasticity: plantar flexor muscles (triceps sural: gastrocnemius and soleus), tibialis posterior, flexor digitorum longus.

ree consecutive injections of 200-300 units of OnabotulinumtoxinA (Botox ®) under ultrasound guidance. The BoNT/A will be distributed according to the individual clinical pattern of spasticity: plantar flexor muscles (triceps sural: gastrocnemius and soleus), tibialis posterior, flexor digitorum longus.

Step time (Temporal gait parameter) is expressed in seconds and assessed with instrumented gait analysis

Step length (Spatial gait parameter) is expressed in meters and assessed with instrumented gait analysis

Inclusion Criteria: First-ever Ischemic or haemorrhagic stroke Time since stroke onset: >6months Hemiparesis with equinovarus foot No previous BoNT/A Exclusion Criteria: Non-ambulant patients Medical contraindications for BoNT/A use that appear in the product information sheet

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