High Failure Rate of a Decellularized Osteochondral Allograft for the Treatment of Cartilage Lesions.

Background: Widespread adoption of fresh allograft transplantation remains limited, predominantly by supply issues. To overcome these limitations, a preshaped, cylindrical sterilized and decellularized osteochondral allograft (SDOCA) implant was recently introduced as a clinical treatment option.

Purpose: To evaluate functional outcomes and graft survivorship among patients treated with the SDOCA implant for knee cartilage injuries.

Study Design: Case series; Level of evidence, 4.

Methods: An institutional review board-approved database was used to identify a series of patients with prospectively collected data who had been treated with the SDOCA implant. The surgeries were performed at 2 centers by 2 surgeons. Patient-reported outcomes, magnetic resonance imaging (MRI), and the number and type of reoperations were assessed. Failure was defined as structural damage of the graft diagnosed by arthroscopy or MRI, and any reoperation resulting in removal of the allograft. Patients were evaluated pre- and postoperatively using the Knee injury and Osteoarthritis Outcome Score (KOOS) and Marx Sports Activity Scale. MRI was assessed preoperatively and postoperatively.

Results: There were 32 patients with a mean age (±SD) of 35.1 ± 10.6 years; 59% were male. Twenty-three (72%) knees had previous surgery. The mean defect area (±SD) was 2.9 ± 2.0 cm(2), and the mean allograft size was 13.18 ± 2.3 mm (6 grafts ≤9 mm and 59 grafts ≥11 mm). The median number of allografts per knee was 2 (range, 1-5 grafts). Twenty-three of the 32 knees (72%) were considered failures by the definition detailed above. Of these, 14 knees (43%) had further surgery after the index procedure. Implant survivorship was 19.6% at 2 years. The mean follow-up duration was 1.29 years (range, 0.11-2.8 years). KOOS pain, activities of daily living (ADL), sports and recreation (sport/rec), and knee-related quality of life improved significantly from the preoperative visit to latest follow-up. Age was significantly predictive of failure, with a hazard ratio of 1.68 per 1 SD older (95% CI, 1.05-2.68; P = .030). The MOCART (magnetic resonance observation of cartilage repair tissue) feature effusion was the only score to correlate with KOOS (symptoms, pain, ADL, sport/rec).

Conclusion: The SDOCA implant demonstrated a 72% failure rate within the first 2 years of implantation at these 2 institutions.