[Experimental studies of autograft with cancellous bone in the diaphysis of long bone (author's transl)].

The acceptance of fresh autologous cancellous bone in a wedge-shaped diaphysial cortical defect was examined in 2 groups of 5 dogs microangiographically and histologically 1,2,3,4 and 6 weeks after transplantation. The main recanalisation takes place after one week from the medullary canal, two weeks later periosteal vessels are connected and finally three weeks later the tender vessels of the Haversian canal system within the cortex are being integrated. Histologically, after one week active formation of fibrous bone can be seen adjacent to numerous capillaries originating within the medullary canal. Simultaneously, considerable degradation of transplanted trabeculae by mono- or polynuclear osteoclasts takes place. Formation of new bone occurs according to newly built capillaries. After 4 weeks, transplanted trabeculae can be found only sparsely, the new fibrous bone is being remodelled into lamellar bone. After 6 weeks, the entire fibrous bone has been transformed into lamellar bone and is calcified. A trajectorial orientation of the Haversian system according to that of the host cortical bone can be recognized vaguely.