Does botulinum neurotoxin-A intramuscular injection induce local muscular weakness in adult-onset neurological patients with focal muscle spasticity? A systematic review.

Abstract

Botulinum neurotoxin-A (BoNT-A) injections are commonly used and effective for the treatment of focal spasticity. However, the impact on strength is widely unknown. This study aimed to investigate the effect of BoNT-A injections on focal muscle strength in adult-onset neurological conditions. Overall, the impact of BoNT-A on muscle strength was inconclusive. The impact of BoNT-A injections on muscle strength, when examining long-term outcomes greater than 3 months remains unclear. Many of the clinical strength measures used have limited capacity to detect change. High-quality evidence is required to examine the impact of BoNT-A injections on muscle strength directly. Further investigations may determine the impact BoNT-A injections has on muscle strength, and the impact on function.