Background: Autologous osteochondral transplantation restores a cartilage defect with a cylindrical unit of bone and articular cartilage. Previous studies have described poor graft integration at the chondral interface and degeneration of the cartilage. This has prompted the investigation of adjuncts to address these concerns, including platelet-rich plasma (PRP), which has the potential to improve chondral interface integration and decrease cartilage degeneration. The purpose of this study was to evaluate the effect of PRP on autologous osteochondral transplantation in a rabbit model.
Methods: Bilateral osteochondral defects (2.7 mm in diameter and 5 mm in depth) were created on the femoral condyles of twelve New Zealand White rabbits. Osteochondral grafts were harvested from the ipsilateral femoral condyle and, after randomization, were treated with either PRP or saline solution before implantation into the defect site. The rabbits were killed at three, six, or twelve weeks postoperatively. The osteochondral graft was assessed using the International Cartilage Repair Society (ICRS) macroscopic and modified ICRS histological scoring systems.
Results: Macroscopic assessment revealed no significant difference between the two groups (mean and standard deviation, 11.2 ± 0.9 for the PRP-treated group versus 10.3 ± 0.9 for the control group; p = 0.09). The mean modified ICRS histological score was significantly higher overall and at each time point for the PRP-treated osteochondral transplants compared with the controls (overall mean, 18.2 ± 2.7 versus 13.5 ± 3.3; p = 0.002). Assessing graft integration specifically, the mean score for the PRP-treated group was significantly higher than that for the control group (2.5 ± 0.9 versus 1.6 ± 0.7; p = 0.004). No adverse events occurred as a result of the surgical procedure or PRP.
Conclusions: PRP may improve the integration of an osteochondral graft at the cartilage interface and decrease graft degeneration in an in vivo animal model.
Clinical Relevance: The use of PRP as a biological adjunct to autologous osteochondral transplantation has the clinical potential to enhance graft integration, decrease cartilage degeneration, and improve clinical outcomes of autologous osteochondral transplantation.
1Hospital for Special Surgery, 523 East 72nd Street, Suite 507, New York, NY 10021. E-mail address for N.A. Smyth: SmythN@hss.edu