Sixteen studies were included in the review (n=262), including four RCTs (n=105), of which one was double-blinded, eight case series (n=147) and four case studies (n=10). All the RCTs were rated as strong; all other studies, with the exception of one case series which was rated medium, were considered to be weak.
Spasticity/tone (four RCTs, six case series and two case studies):
There was conflicting evidence on the impact of BTX-A on spasticity/tone. Two RCTs showed significantly lower Ashworth scale scores in the intervention group, but two showed no difference between the groups. Four of the case series showed a significant reduction after treatment but two showed no differences.
ROM (three RCTs, six case series, one case study):
Two RCTs and two case series found significant improvements in ROM, while one RCT and four case series showed no significant benefit.
Functional gains of upper limb:
A wide range of functional outcomes were reported by studies with a high level of clinical heterogeneity. Three RCTs showed significant differences in favour of the BTX-A group in functional activities, while five case series reported improvements relative to baseline. One RCT showed no differences between the groups, while three case series showed no significant improvement following BTX-A treatment.
Adverse events:
The only adverse event reported was a weakening of grip strength in one RCT and one case series.