Comparison of the effects of recombinant human epidermal growth factor (rhEGF) and alendronate sodium on tibial fracture healing in rats: an experimental study

Abstract

Purpose: The objective of this study is to compare the effects of recombinant human epidermal growth factor (rhEGF) on bone healing with those of alendronate, a bisphosphonate widely used in practice. Materials and Methods: An iatrogenic fracture was created in the tibial shaft of 24 Sprague-Dawley rats with osteotome and fixed with an intramedullary Kirschner wire (K-wire). After surgery, Group 1 was given 0.2 mg/kg/day of oral alendronate sodium on postoperative Day 1 to 28, Group 2 received a single dose of 0.5 mg/kg of intraosseous rhEGF on postoperative Days 1 and 14, and Group 3 was followed for a total of four weeks with oral saline. At the end of Week 4, the animals were euthanized and the lower extremities were removed by stripping the soft tissues without damaging the callus. Tissue samples of groups were prepared and and stained with hematoxylin-eosin. After staining, histological scoring was performed to evaluate the degree of union. Results: Alendronate sodium group demonstrated a mean histological score of 6.95± 1.28. The rhEGF group had a lower mean score of 4.85±1.66. The placebo group exhibited the least progress in bone healing with a mean score of 4.10±1.68. The histological score was significantly higher in the alendronate sodium group compared to both the rhEGF and placebo groups. There was also a statistically significant difference between the rhEGF and placebo groups in terms of scores. Conclusion: Alendronate sodium enhanced fracture healing processes in rats. The role of rhEGF in bone healing requires further exploration. As the understanding of bisphosphonates and growth factors in bone healing evolves, the strategies for optimizing patient care in orthopedic settings are expected to be developed.