Add-on benefits of botulinum toxin type A in combination or sequential therapies for scar management: a systematic...

Botulinum toxin type A (BoNT-A) has been increasingly incorporated into multimodal scar management strategies as an adjunctive treatment. However, the additive benefits of BoNT-A when used in combination or sequential therapeutic approaches remain unclear due to limited and heterogeneous evidence.

A systematic review and meta-analysis of randomized controlled trials was conducted in accordance with the PRISMA guidelines. PubMed, Embase, and the Cochrane Library were searched to identify studies evaluating BoNT-A as an add-on intervention in combination or sequential scar management strategies. Eligible studies compared BoNT-A plus standard scar management with control interventions alone. Primary outcomes included validated scar assessment scores, namely the Vancouver Scar Scale (VSS) and the Stony Brook Scar Evaluation Scale (SBSES). Pooled analyses were performed using mean differences (MDs) with 95% confidence intervals (CIs).

Six randomized controlled trials (RCTs) were included. The pooled analysis suggested that BoNT-A add-on therapy significantly improved scar appearance, with a Mean Difference (MD) of -1.80 for the VSS score and 1.46 for the SBSES score. However, this represents low-certainty evidence.

Current low-certainty evidence suggests that BoNT-A may provide a potential adjunctive benefit for improving scar appearance, particularly in mitigating local mechanical tension. However, because these pooled estimates reflect a composite of heterogeneous treatment paradigms, the findings are suggestive rather than confirmatory and strictly exploratory. Clinical application should remain cautious and individualized, pending further high-quality, standardized RCTs.

https://www.crd.york.ac.uk/PROSPERO/view/CRD420261354679, PROSPERO CRD420261354679.