Effect of pentoxifylline on healing of segmental bone defects and angiogenesis.

Objective: The aim of this study was to determine the effect of pentoxifylline (PTX) on angiogenesis and the healing of a critical-sized segmental defect of the radius diaphysis in a rat model, using radiological and histological grading systems.

Methods: The study included 24 female Sprague-Dawley rats (weight: 300±20 g) divided into 4 groups. A critical-sized segmental defect was created in the radius diaphysis in all rats. In Group 1, morcellized iliac crest autografts were used to fill the segmental bone defect. In Group 2, segmental bone defects were filled using morcellized iliac crest autografts, and 25 mg/kg/day PTX was applied intraperitoneally. In Group 3, the segmental bone defects were not filled, and in Group 4 the segmental bone defects were left unfilled, and an intraperitoneal (IP) dose of 25 mg/kg/day PTX was applied. Rats were sacrificed at postoperative Week 8, and defects were evaluated using radiographic, histological and immunohistochemical methods.

Results: There were significant differences between Group 1 and 2 according to radiological evaluation (p=0.003) and quality of union at the defect site (p=0.01). Union quality was higher in Group 4 than Group 3 (p=0.01). Cluster of differentiation 31 (CD31) and vascular endothelial growth factor (VEGF) levels were higher in Group 2 than in Groups 3 and 4.

Conclusion: According to radiological and histological parameters, PTX appears to improve angiogenesis and healing of segmental cortical bone defects of the radius in a rat model.