Therapy effects of testosterone on the recovery of bone defects

Androgens have proliferative effects on osteoblasts and increase fracture healing by systemic and local stimulation of bone formation. The aim of the present study was to evaluate if the systemic stimulation by androgens leads to increased bone-defect healing. 1.5-mm trepanation defects were created in the femoral diaphysis of 30 Sprague-Dawley rats. 10 animals were used as untreated controls and 10 animals per group were treated by intramuscular injection of 1 or 10 mg dihydrotestosterone two days prior to surgery. After 14 days the samples were explanted and examined by macroscopy, histology and histomorphometry. All animals were included into the study and were analysed. Clinical observation showed no complications. Macroscopic examination and histology showed no significant differences. All defects were filled with trabecular bone in direct contact to the surrounding bone. Histomorphometry showed a significantly decreased bone content in the controls in comparison to both therapy groups, while the therapy groups showed no significant differences between each other. The stimulation of healing of bone defects with androgens leads to a significantly higher bone content inside the defects. In clinical application, androgens may be a possibility to increase bone formation, especially in elderly patients. Furthermore, it may be possible to shorten postoperative rehabilitation because of the effects of androgens on muscles.