Chahla J, Sweet MC, Okoroha KR, Nwachukwu BU, Hinckel B, Farr J, Yanke AB, Bugbee WD, Cole BJ. Osteochondral Allograft Transplantation in the Patellofemoral Joint: A Systematic Review. Am J Sports Med. 2019 10; 47(12):3009-3018.