The Effect of Subcutaneous Platelet-Rich Plasma Injection on Viability of Auricular Cartilage Grafts

Although cartilage grafts are frequently used for structural integrity and volume restoration, one of the main concerns dealing with cartilage grafting is gradual volume loss and unpredictable viability rates of cartilage grafts. Platelet-rich plasma (PRP) is a well known platelet concentrate reported to enhance cartilage repair and stimulates chondrocyte proliferation and matrix biosynthesis. The purpose of the current study was to investigate the effect of subcutaneous PRP injection on improving the viability of cartilage grafts. Six circular cartilage grafts were obtained from auricular cartilages of 6 New Zealand white rabbits. Cartilage grafts were prepared in 3 forms: block, crushed, and crushed/wrapped with Surgicel (Surgical, Ethicon, Somerville, NJ). Grafts were placed to 6 dorsal subcutaneous pockets and pockets were closed. Autologous PRP was prepared and injected subcutaneously into the pockets of experiment groups. At the end of 8 weeks, cartilage grafts were removed. Cartilage mass reduction rates were measured. Resorption rates of cartilage grafts and formation of fibroelastic and bone tissue were microscopically evaluated. All of the cartilage grafts lost significant weight. Viability scores of block cartilages were higher than crushed cartilages. Although less weight loss rates and higher histopathologic scores were obtained in subcutaneously PRP injected cartilage graft groups, these results were not statistically significant. Although our study gives a new insight about increasing the viability of cartilage grafts, the subcutaneous PRP injection did not result in improving the viability of cartilage grafts in this experimental design.