THE FATE OF FRESH AND PRESERVED, NONCRUSHED AND CRUSHED AUTOGENOUS CARTILAGE IN THE RABBIT MODEL

This study was conducted to investigate volume retention and chondrocy te survival rate in autogenous fresh noncrushed, fresh crushed, preser ved noncrushed, and preserved crushed cartilage grafts in rabbits. Dur ing the first phase of this investigation, cartilage was harvested fro m the right ear of 20 New Zealand white rabbits, then preserved. Four months later during the second phase, two 6-mm discs of previously har vested and preserved cartilage, one crushed and one noncrushed, were a pplied to the right ear. At the same time, two 6-mm discs of fresh car tilage graft were harvested from the left ear and then placed at a hig her level on the same side, one crushed and one noncrushed. Three mont hs after implantation, the rabbits were sacrificed and the grafts were evaluated. The preserved noncrushed cartilage retained 91.34% of the volume (SD = 2.46). Although most of the chondrocytes were nonviable, vascular ingrowth occurred with a significant repopulation of chondroc ytes peripherally, in association with vascular endothelial ingrowth. The preserved crushed cartilage retained 74.19% of the volume (SD = 3. 06). Most of the original chondrocytes were lost, but vascular ingrowt h did occur and some osteoid formation occurred on the crushed cartila ges. All chondrocytes on the fresh noncrushed cartilage grafts were vi able and the grafts retained 94.54% of the volume (SD = 2.46). Crushed fresh cartilage retained 69.73% of its volume and the amount of viabl e chondrocytes ranged from 70% to 90% in the specimens evaluated (SD = 5.15). Although there is no question that noncrushed cartilage is sup erior, crushed cartilage can be used with a fair degree of predictabil ity to attain the aesthetic goal. However, overcorrection is necessary to achieve optimal final results.