A Resveratrol-Loaded Scaffold Enhances Tendon Healing: Histological and Biomechanical Analysis in a Rat Achilles Tendon Repair Model

Aim: This study aims to evaluate the effects of Dermalix® (Dx), a resveratrol-loaded, bioabsorbable scaffold composed of collagen, laminin, and hyaluronic acid, on tendon healing and peritendinous adhesion formation following primary Achilles tendon repair in a rat model. Materials and Methods: A total of 28 female Wistar Albino rats underwent bilateral Achilles tendon injury and repair using the modified Kessler technique. The right legs were treated with local Dx application over the repair site, while the left legs served as untreated controls. Animals were randomly allocated into four groups (n = 7/group) based on the evaluation time points: 3rd and 6th weeks, for histological and biomechanical assessments, respectively. Macroscopic adhesion scoring, histological quantification (including counts of fibroblasts, fibrocytes, and vessels), and biomechanical testing (maximum load to failure and elongation before rupture) were performed. Statistical comparisons were conducted using t-test, Mann-Whitney U, chi-square, ANOVA, or Friedman test where appropriate. Results: Dx application significantly reduced macroscopic adhesion grades at both 3 and 6 weeks (p<0.01). Histological analyses revealed significantly lower fibroblast and fibrocyte counts in Dx-treated groups (p < 0.05), accompanied by more organised collagen alignment. Biomechanically, rupture force was significantly higher in Dx groups at both time points (p<0.001 and p=0.029), while no significant difference was found in elongation distance. The scaffold was macroscopically resorbed by week 3, without eliciting a foreign body reaction or systemic side effects. Conclusion: The local application of Dermalix significantly enhanced tendon healing and reduced peritendinous adhesions without compromising biomechanical strength. Its bioabsorbable composition and local antioxidant properties make Dx a promising adjuvant candidate in tendon repair strategies, particularly in cases with high adhesion risk.