The effect of delayed internal fixation on healing of the osteotomized dog radius

Delay in surgical intervention has been reported to enhance the process of fracture healing. Quantitative observations or experimental osteotomies were made to investigate the mechanical for such enhancement. Eight mongrel dogs with bilateral radial osteotomies were prepared with immediate plate fixation on the right side, and with delayed fixation two weeks later on the left side. The response to delayed fixation was measured radiographically, mechanically, and by measurement of new bone formation using a quantitative tetracycline incorporation method. A clearly discernible stimulation of new bone formation occurred early in the osteotomy healing process. Delayed fixation has a transient stimulatory effect on the healing process of bone.