Repair of experimental autologous grafts of cortical bone.

Fresh autologous segmental grafts of fibula, four centimeters long, were obtained from thirteen adult dogs. Holes were drilled in each before replantation. The amount of repair was determined after intervals of from four to twenty-four weeks. Torsional stress testing showed that the six drill holes 500 micrometers in diameter confined within an expanse of two centimeters did not mechanically weaken the transplants at the time of surgery. The drill holes were rapidly filled with cancellous bone which matured to cortical bone within twelve weeks. Microradiography and tetracycline labeling of drilled and non-drilled grafts demonstrated similar biological reparative patterns.