Harvest Technique Does Affect the Quality of Osteochondral Grafts: Histologic Evaluation Comparing Commercial Standards versus Scalpel Blade Technique

Abstract

Objective While the percentage of viable cells is a major determinant of graft performance during osteochondral allograft (OCA) transplantation, the baseline chondrocyte viability at the periphery of osteochondral plugs is defined at the time of harvest. In this laboratory study, we aimed to determine the optimal technique for OCA plug harvest by evaluating commercial standard techniques compared to sharp blade harvest technique. Design Osteochondral explants were harvested from bovine and human samples using 3 different techniques: (1) standard OATS manual punch device (Osteochondral Autograft Transplant System OATS; Arthrex, Naples, FL), (2) powered trephine device, and (3) fresh scalpel blade. Chondrocyte viability and the dead area at the periphery of the tissue were evaluated by LIVE/DEAD staining. Safranin-O and fast-green were performed for structural evaluation. Results For both bovine and human samples, the dead area at the periphery of the explant was significantly smaller after scalpel blade preparation compared to harvest with OATS ( P < 0.001) and powered trephine devices ( P < 0.001). In addition, while powered device had a smaller remaining dead area compared to the OATS device ( P < 0.001), there was significantly greater tissue loss and peripheral contour change for plugs harvested with the powered trephine device. Conclusion Our study demonstrated that OCA plugs harvested with OATS and powered device lead to a significant mechanical injury at the periphery of the explants compared to a scalpel. We propose that the optimal technique for OCA harvest utilizes a combined approach incorporating a scalpel blade/circular scalpel to prepare the chondral surface and a powered trephine to prepare the osseous surface.