II Reconstruction of Articular Surface Using an Autogenous Osteochondral Fragment Preserved Loose in the Joint Cavity: An experimental study

Fixation of an osteochondral fragment preserved as a loose body in the joint cavity to the condylar bed was studied in an experiment carried out in rabbits. An osteochondral fragment was detached from the medial femoral condyle and left loose in the joint cavity. In a second operation 7 days later the fragment was secured to its bed using a bone transplant for fixation. The observation time varied from 7 to 208 days, and the bone specimens were studied macroscopically, by histology, tetracycline labelling, and microradiography.It results that an osteochondral fragment retains its viability in the joint cavity and can be replaced to its bed with excellent or acceptable results in 84% of the cases.Fixation with a bone transplant affords a good stability, and the bone transplant itself participates in the healing process. Healing of the osteochondral fragment develops similarly as in cases where the osteochondral fragment was immediately fixed. Minimal degenerative changes developed, and the cleavage in the articular surface was filled with hyaline and fibrous cartilage. These results seem to support our view that, in certain clinical cases, loose osteochondral bodies can be used in joint surface reconstruction.