The effects of cryopreserved human amniotic membrane on fracture healing: Animal study.

Objective: The aim of this study was to investigate the effects of human amniotic membrane (HAM) on fracture healing in an animal model.

Methods: Standard tibial diaphysial fractures were created in twenty-eight Wistar-Albino rats and treated with intramedullary Kirschner wire (K-wire) and HAM (HAM (+) group) or K-wire only (HAM (-) group). Fracture healing was evaluated by histological analysis, radiologic X-ray views and callus diameter measurements at 3rd and 6th weeks postoperatively.

Results: Fracture healing was histologically better in the HAM (+) group and the difference was statistically significant at both 3rd and 6th weeks postoperatively (p < 0.05). The highest histologic scores and entire woven bone formation (Huo Stage 8-9) were obtained at 6th weeks postoperatively in the HAM (+) group. Histological examination also revealed predominant fibrous tissue and partial cartilage formation (Huo Stage 2) at the postoperative 3rd week in the HAM (-) group. Equal amounts of woven bone and cartilage formation (Huo Stage 6-7) were observed at 3rd weeks postoperatively in the HAM (+) group and at 6th weeks postoperatively in the HAM (-) group. The callus diameters were greater in the HAM (+) group and the difference was statistically significant (p < 0.05) at 3rd and 6th weeks postoperatively. Although there was only a statistically significant difference (p < 0.05) at the postoperative 3rd week, radiological scores tended to be higher in the HAM (+) group at both the 3rd and 6th weeks postoperatively.

Conclusion: HAM is a cheap and easily accessible alternative biological material. HAM may be used to support surgical treatment of fractures, particularly where bone healing is expected to last longer.