There is disclosed a defect sizer tool for selection of an appropriately sized pre-
cut core for a cryopreserved osteochondral allograft (COCA)
transplantation procedure. In an embodiment, the tool includes an elongated connector that provides a
handle portion. A ring measurement guide at one end, with a given
diameter, and alignable with a
cartilage defect to provide an estimated measurement of a
diameter. There is disclosed an instrument kit with a pin, a pin guide, and a
reamer configured to slidingly receive the pin, blades at one end, and a rotational drive connector at the other end. In an embodiment, a method for a COCA
transplantation procedure includes providing an instrument kit, using the pin guide to place the pin in the
subchondral bone, and operating the
reamer to
score surrounding
cartilage prior to the
reamer bit portion reaming the
subchondral bone to the desired depth. Other embodiments are also disclosed.