Effects of botulinum toxin and functional electrical stimulation in individuals with spasticity: a systematic review

Background/Aims Botulinum toxin is a globally recognised method for managing spasticity in people with cerebral palsy, stroke and spinal cord injury. Despite its efficacy, enhancing functionality in these conditions requires complementary therapeutic strategies. Functional electrical stimulation is widely used to support mobility by providing targeted electrical stimulation during functional motor tasks. The aim of this systematic review was to investigate the impact of combining Botulinum toxin A and functional electrical stimulation on functionality in individuals with spasticity. Methods The search, spanning from inception to July 2023, was conducted across PubMed, ScienceDirect, Scopus, and the Cochrane Library. The Downs and Black Checklist was used to assess the methodological quality of the studies. Results The search yielded seven articles out of 605 studies. The included studies exhibited heterogeneity in intervention parameters and, on average, demonstrated fair methodological quality. Conclusions The synthesis indicates that applying functional electrical stimulation after Botulinum Toxin A seems to improve functionality and muscle tone control in upper and lower limbs for conditions such as cerebral palsy, stroke and spinal cord injury. However, uncertainties persist regarding optimal intervention parameters, including the time interval between interventions and treatment frequency and volume. Implications for practice The findings of this review suggest that functional electrical stimulation, when used as an adjuvant therapy to BoNT-A, is effective in achieving clinical rehabilitation goals. These goals include reducing muscle tone in adults, improving gait spatiotemporal parameters in both children and adults, and enhancing manual dexterity in daily activities in adults.