The reduction of extraneural scarring with buccal mucosa graft wrapping around the sciatic nerve: An experimental study in a rat model

Abstract

Background: The postoperative development of epineural and extraneural scar tissue adversely affects peripheral nerve surgery outcomes. Although several surgical methods, pharmacological agents, and chemical materials have been used to prevent epineural scar formation in both clinical and experimental models, the results are still unsatisfactory. The purpose of this study was to investigate the efficacy of buccal mucosa graft (BMG) wrapping on epineural scarring in an adult rat model. Methods: Bilateral sciatic nerves were carefully exposed in 24 adult Sprague-Dawley rats, and a circumferential segment of epineurium (0.5 cm) was excised from both nerves. The epineurectomised left nerve segment was wrapped with a BMG (experimental side), while the right nerve segment did not receive any surgical procedure other than the epineurectomy, and served as the control side. To perform gross and histopathological examinations, 12 randomly selected rats were euthanised at 4 weeks postoperatively, and the remaining rats were euthanised at 8 weeks. Results: The left sciatic nerve that was wrapped with a BMG following epineurectomy showed significantly less nerve adhesion at 8 weeks (p = .018), and less epineural scar tissue at both 4 (p = .014) and 8 weeks (p = . 025). Inflammation of the BMG-wrapped nerves was increased at 4 weeks (p = .029), but not at 8 weeks. Conclusion: BMG wrapping decreases postoperative adhesion and scar tissue formation of epineurectomised healthy nerves, despite the presence of increased inflammation in the early postoperative period.