Osteochondral Graft Size Is Significantly Associated With Increased Force and Decreased Chondrocyte Viability

Background:Insertion force has been shown to significantly reduce chondrocyte viability during osteochondral allograft transplantation. How graft size influences the required insertion force and chondrocyte viability has yet to be determined.Hypothesis/Purpose:The purpose was to characterize how graft size influences insertion force requirements and chondrocyte viability during osteochondral transplantation. The hypothesis was that larger grafts would require greater force and reduce chondrocyte viability.Study Design:Controlled laboratory study.Methods:Four graft sizes—15 × 5 mm, 15 × 10 mm, 25 × 5 mm, and 25 × 10 mm (diameter × depth)—were harvested from 13 thawed fresh-frozen human cadaveric distal femurs. Average, maximum, and cumulative force and number of impacts were recorded for 44 grafts by a surgical mallet embedded with a calibrated force sensor. In a separate experiment, fresh osteochondral tissues were subjected to mechanical loading. To capture a range of clinically important forces, categor...