Effectiveness of repeated injections of botulinum toxin A on gait and fatigue in adults with spastic paraparesis secondary to multiple sclerosis.

Background: Multiple sclerosis (MS) is the most common neurologic disease in young adults. Spasticity is one of its most disabling symptoms, with botulinum toxin A type A (BoNT-A) being one of the treatments of choice for this symptom.

Objective: We assessed the response to abobotulinumtoxinA in improving walking ability and fatigue in patients with spastic paraparesis caused by MS.

Methods: We performed a real-world, multicenter, prospective, open-label low-intervention trial in 84 patients with MS and spastic paraparesis of the lower limbs infiltrated with abobotulinumtoxinA (LINITOX study). The response of spasticity, walking ability and fatigue is analyzed in 4 cycles of ultrasound-guided injection in the lower limbs.

Results: The patients improved their walking ability by an average of 11.34% meters measured with 6-Minute Walk Test (6MWT), and decreased the percentage of fatigue by 6.86% (4.66 percentage points less), in the 12-Item Multiple Sclerosis Walking Scale (MSWS-12) 4 weeks after abobotulinumtoxinA injection, both values are statistically significant. This improvement seems to persist over time, throughout the cycles.

Conclusion: We found improved walking ability and less fatigue in patients with MS-related spastic paresis of the lower limbs after injection of abobotulinumtoxinA.