A Novel Autologous Osteoperiosteal Composite for Osteochondral Regeneration

Background: Osteochondral defects result in persistent knee pain and functional impairment, and remain a clinical challenge to repair effectively. Purpose: To evaluate the efficacy of an autologous inverted subchondral bone-periosteum composite graft for osteochondral reconstruction. Study Design: Controlled laboratory study. Methods: A total of 30 mature New Zealand White rabbits were randomly assigned to 3 groups: microfracture (MF) (n = 10), osteoperiosteal composite graft (OPC) (n = 10), and untreated control (n = 10). A 2 mm–diameter osteochondral defect was created in the control and MF groups and left untreated in the control group. In the MF group, microfracture was then performed by creating four 4 mm–deep perforations in the defect bed using Kirschner wires. A cylindrical osteochondral autograft (2 mm diameter × 4 mm height) was aseptically harvested from the intercondylar fossa using a calibrated coring drill only in the OPC group. Group-specific treatments included defect creation without reparative intervention (control), defect creation followed by subchondral perforation (MF), and inverted autograft implantation with periosteal wrapping (OPC). Animals were euthanized at 6 and 12 weeks postoperatively (n = 5 per group per time point) for gross and histological evaluation. Results: At 6 weeks, fibrocartilaginous tissue partially filled the defects in all groups. By 12 weeks, the OPC group exhibited a significant reduction in defect area compared with the preoperative baseline, with >75% of the defect depth filled, significantly outperforming the control group. Histological analysis confirmed the superior regenerative performance of the OPC group, with scores of 26.20 ± 1.48, compared with 21.80 ± 2.68 in the MF group and 15.60 ± 2.61 in controls (OPC vs MF, P = .0280; OPC vs Control, P <.0001). Conclusion: The osteoperiosteal composite graft promotes osteochondral regeneration by synergistically enhancing progenitor cell recruitment and chondrogenic differentiation. Clinical Relevance: This single-stage procedure offers a biomimetic, surgically practical, cost-effective, and arthroscopically compatible strategy for repairing osteochondral lesions.