Purpose: Alterations in bone-healing ability after intraoperative radiotherapy were investigated in relation to different doses and postradiotherapy intervals in an experimental model.
Methods and materials: Bilateral osteotomy of the fibulae of 56 rabbits was carried out either immediately, 13 weeks or 39 weeks after unilateral intraoperative radiotherapy with 10-MV X ray using one of three doses, 25, 50, or 100 Gy. The healing of the fibulae was evaluated radiographically and histologically 13 weeks after the osteotomy.
Results: Bone-healing ability was irreversibly reduced in all irradiated fibulae and these damages occurred in a dose-dependent manner. The severity of the damage also tended to increase with the time interval between irradiation and osteotomy. This interval-related aggravation was characterized by augmented bone loss at the osteotomy ends and atrophy of the neighboring areas.
Conclusion: These results serve as useful information concerning the surgical intervention of irradiated bone during and after intraoperative radiotherapy, and also after conventional radiotherapy.