Botulinum Toxin Type A for Preventing Facial Trauma and Hypertrophic Scars: A Meta-Analysis and Trial Sequential Analysis.

OBJECTIVE

To evaluate the effectiveness and safety of local injection of botulinum toxin type A in preventing hypertrophic scars after facial trauma and surgery using meta-analysis and sequential experimental analysis methods.

METHOD: Computer retrieval of randomized controlled trials on the prevention of facial scars with botulinum toxin type A from PubMed, EMbase, the Cochrane Library, CNKI, China Biomedical Literature Service System, Wanfang Database, and VIP Chinese Science and Technology Journal Full text Database up to February 2025.

RESULT: Twelve randomized controlled clinical trials were included, with a total of 644 patients; Type A botulinum toxin injection is superior to the control group in improving patient satisfaction [RR = 6.89; 95% CI (3.20, 14.85); p < 0.0001], Vancouver Scale score [RR = -1.40; 95% CI (-2.73, 0.08); p < 0.0001], visual analog score [RR = 1.41; 95% CI (0.26, 2.56); p = 0.02], scar width [RR = -0.14; 95% CI (-0.17, -0.10); p < 0.0001], and the difference is significant; The incidence of adverse events [RR = 0.38; 95% CI (0.18, 0.84); p = 0.02] and recurrence rate [RR = 0.17; 95% CI (0.04, 0.81); p < 0.03] were lower than those in the control group, and no serious adverse reactions occurred; Sensitivity analysis showed that the results were relatively robust, sequential analysis of the experiment showed that the benefits were conclusive, and Begg's and Egger's tests showed no publication bias.

CONCLUSION

Type A botulinum toxin injection has a certain therapeutic effect on hypertrophic scars without significant side effects. However, the accuracy and stability of its therapeutic effect still require more high-quality research verification.