Incongruity affecting osteochondral repair by mosaicplasty technique in an animal model.

OBJECTIVE

To compare the influence of the different osteochondral incongruity grades on the osteochondral repair by the mosaicplasty technique in a goat model.

METHODS

The acute defects were created in the weight-bearing area of the medial femoral condyle of the goats. Mosaicplasty was done to repair the defects. While implanting the cylindrical osteochondral grafts, different osteochondral sunk, or elevated incongruities were created. The goats were killed 12 weeks after operation to receive gross and histology observation, which was evaluated by the histological grading scale of O'Driscoll et al. The specimens were also taken for transmission electron microscope examination. Two factors analysis of variance and Student-Newman-Kewls test were used to compare the specimen.

RESULTS

Minimal steps, which were less than the thickness of cartilage, possess a capacity for remodeling that can correct initial incongruities while preserving hyaline characteristics. However, the step more than the thickness of cartilage could not be repaired satisfactorily.

CONCLUSIONS

The incongruity could have an influence on the repair by the mosaicplasty technique in a goat model. The limited incongruity could be repaired by a vigorous remodeling process.