Osteochondral Allograft Transplantation

Overview

Osteochondral allograft transplantation, or OCA, replaces a damaged section of cartilage together with the bone beneath it, using a single, size-matched piece of donor bone and cartilage. Dr. Raffo uses OCA when a defect involves the subchondral bone itself — from osteochondritis dissecans, prior failed surgery, or a large traumatic lesion — damage cartilage-only techniques cannot fix.

How Dr. Raffo Performs This Procedure

The recipient site is prepared arthroscopically or through a small arthrotomy to define the size and depth of the defect precisely. A donor allograft — cadaveric bone and cartilage matched to the patient's anatomy — is then shaped to fit and press-fit into the prepared socket, restoring both the bony architecture and the joint surface in a single procedure. Unlike MACI, there is no separate biopsy stage; OCA is single-stage from the patient's perspective, though the graft itself has already gone through donor screening and preparation before it reaches the operating room (FDA — MACI, for comparison of two-stage structure).

Who Is This For?

OCA is best suited to larger lesions and lesions with meaningful bone involvement. In the literature, mean lesion size for OCA runs around 5.05 cm² and has been reported as large as 25 cm² in osteochondritis dissecans populations (Wang X, OJSM 2023; Sadr et al. 2016). It is a strong option for patients with OCD, prior failed cartilage surgery, or defects where the bone stock itself needs to be restored, not just resurfaced. OCA is not the first choice for a smaller, purely chondral defect without bone loss — a two-stage cell therapy or, if the arthritis grade fits, a single-stage scaffold may be more appropriate for that patient, and it is not indicated in a knee with diffuse arthritis rather than a focal, bone-involving lesion.

Recovery & Rehabilitation

OCA requires a more protected recovery than a cartilage-only procedure because the graft includes bone that must incorporate into the patient's own skeleton, not just soft tissue that must heal.

• 0–6 weeks: Protected, limited weight-bearing to allow the bony portion of the graft to begin incorporating.
• 6–12 weeks: Progressive weight-bearing as incorporation advances, guided by follow-up imaging.
• 3–6 months: Return to low-impact conditioning for most patients.
• 11 months (mean): Athletes return to sport at a mean of 11.1 months, with a reported range of 6 to 26 months (Touhey et al. 2025).