Botulinum toxin type A for upper limb spasticity after stroke

Abstract

Spasticity is involuntary overactivity of muscles that occurs following upper motor neuron damage to the brain or spinal cord. Upper limb spasticity is common after stroke and can cause deformity, pain and reduced function. Botulinum toxin type A is a neurotoxin produced by the bacterium Clostridium botulinum that blocks the release of acetylcholine from cholinergic neurons. When given by intramuscular injection it causes temporary local paresis and has become an important component of focal spasticity treatment. Randomized controlled trials have shown that botulinum toxin type A can decrease upper limb spasticity and improve the ease of performing basic upper limb functional activities, such as cleaning the hand or dressing a sleeve. This article will review the pharmacology of botulinum toxin type A and its clinical efficacy when used to treat upper limb spasticity after stroke.

Keywords::

• botulinum toxin
• spasticity
• stroke
• upper limb

Financial & competing interests disclosure

The authors are currently undertaking a randomized controlled trial to evaluate the clinical effectiveness and cost–effectiveness of treating upper limb spasticity due to stroke with botulinum toxin type A funded by the National Institute for Health Research, Health Technology Assessment Programme (ISRCTN 78533119)[60]. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.