[Effects of exogenous basic fibroblast growth factor on in-sheathed tendon healing and adhesion formation]

Abstract

Objective: To explore the effects of exogenous basic fibroblast growth factor (bFGF) on in-sheathed tendon healing and adhesion formation.

Methods: Ninety Leghorn chickens were randomly divided into 3 groups (groups A, B and C), 30 animals for each group, and the right third digitorum longus tendon of the chicken was transected to make defect models. In group A, the tendon was sutured in situ after transection. In group B, the tendon was sutured after 0.6 microl fibrin sealant (FS) was applied at repair site. In group C, the tendon was sutured after 0.6 microl FS mixed with 500 ng bFGF was applied at repair site. At 1, 2, 4 and 8 weeks after operation, the tendons of 6 chickens in each group were harvested for morphological and histological evaluation. Six specimens of each group was obtained for biomechanical test at 8 weeks.

Results: The gross observation showed that the differences of grading of tendon adhesion were not significant between groups A, B, and C 8 weeks after operation (P > 0.05). Histological evaluation showed that there were no significant differences in fibroblast counting and the content of collagen fibers between groups A and B (P > 0.05). The angiogenesis, fibroblast proliferation and collagen production in the sheath, epitendon and parenchyma at repair site in group C occurred earlier and were more than those in groups A and B, showing significant differences (P < 0.05). The biomechanical tests showed that the gliding excursion of the tendon in group A, B and C were 3.44 +/- 0.43, 3.51 +/- 0.56 and 2.84 +/- 0.42 mm respectively; the work of flexion were 14.87 +/- 1.72, 14.08 +/- 1.85 and 20.62 +/- 3.52 Nmm respectively; the ultimate tensile strength of the tendon was 10.34 +/- 1.45, 11.26 +/- 1.83 and 15.02 +/- 2.20 N respectively; showing no significant differences between groups A and B (P > 0.05), but showing significant differences between group C and groups A, B (P < 0.05).

Conclusion: The exogenous bFGF at tendon repair site can facilitate in-sheathed tendon healing, but also increase the tendon adhesion formation.