Patients that are enrolled in this study will receive an osteochondral allograft from tissue that has been stored in the MOPS instead of the currently standard preservation system (culture media at 4 degrees Celsius). This will be the only difference in the surgical procedure between enrolled patients and non-study patients. Enrolled patients will undergo their grafting procedure as they normally would if they were not enrolled in this study. They will also receive the same care as non-study patients.