Autologous resurfacing.

Background: There is a discrepancy between the interest in joint-reconstructions and the current knowledge about the healing-processes involved. Major reconstructions are performed with osteosynthesized allografts and fresh allografts for cartilage.

Objectives: The main question to be answered is: what do we know about metaphyseal and epiphyseal cancellous bone healing, contact healing of the subchondral bone and its influence on cartilage healing? Can we achieve healing of all four compartments in contact?

Purpose: The purpose is to systematically investigate through animal testing the healing processes of metaphyseal and epiphyseal bone, including the subchondral bone and the healing of cartilage of press-fit-inserted grafts, considering nondemineralized high-resolution histology.

Material And Methods: Primary cancellous-bone healing of osteosynthesized hemi-osteotomies was studied in 13 canine tibial heads, the contact healing was investigated in 7 dogs and 18 giant-rabbits comparing contact-healing of press-fit-inserted autologs cylindrical grafts with empty defects applying the wet-grinding diamond-technology. Bench-experiments on the epiphyseal bones of swine including pullout-tests of cylindrical grafts formed the basis for validation of that press-fit diamond technology.

Results: Primary metaphyseal and epiphyseal contact healing, including hyaline cartilage, was found in all compartments of the meta-and epiphysis in the precisely performed experiments. The press-fit principle, which employs cylindrical grafts and diamond instrumentation featuring a difference of 15/100 mm between graft and recipient bed, achieved high loads between 73.48 and 178.95 N (mean value 118.16 and standard deviation 32.79) in the pullout tests.

Conclusion: Autologous press-fit grafting with alignment of the bony baseplate using wet-grinding precision has attained promising histo-morphological results.