Bone Grafting Using Manually Contoured Femoral Head and Neck Allograft Successfully Fills Femoral and Tibial Tunnel Osteolytic Defects in 2-Stage Revision Anterior Cruciate Ligament Reconstruction: A Computed Tomography-Guided Analysis.

PURPOSE: To use computed tomography (CT) to quantify the percent filling of tibial and femoral tunnel osteolytic defects using a manually contoured femoral head and neck allograft prior to definitive revision anterior cruciate ligament reconstruction.

METHODS: Patients under 50 years were included if they underwent bone grafting of tibial and/or femoral tunnels with femoral head and neck allograft during 2-stage revision anterior cruciate ligament reconstruction between 2019 and 2024. Patients must have obtained a CT scan at a minimum of 3 months after bone grafting. Percent filling was calculated on axial CT as the ratio of the cross-sectional area of the graft to the reamed tunnel and to the total osteolytic defect. Percent filling was measured through the full tunnel depth and 15 mm from the intra-articular aperture. A cost-minimization analysis was performed comparing femoral head and neck allografts with prefabricated allograft bone dowels.

RESULTS: Twenty tibias and 15 femurs underwent bone grafting. Postoperative CT was obtained at an average of 123.0 ± 14.3 days (range: 109-169 days). Percent filling of tibial tunnels was 92.0% (reamed tunnel, full depth), 92.3% (reamed tunnel, 15 mm depth), 80.4% (entire defect, full depth), and 81.8% (entire defect, 15 mm depth). Percent filling of femoral tunnels was 77.9% (reamed tunnel, full depth), 82.0% (reamed tunnel, 15 mm depth), 68.1% (entire defect, full depth), and 71.3% (entire defect, 15 mm depth). Intraclass correlation coefficients for graft and tunnel measurements were 0.9897 and 0.9804, respectively. In 14 patients who underwent tibial and femoral tunnel bone grafting, paired analyses showed greater percent filling in tibial tunnels (P < .05). There were no postoperative complications. Femoral head and neck allografts were associated with lower costs compared with prefabricated dowels.

CONCLUSIONS: Manually contoured femoral head and neck allografts adequately fill osteolytic defects in tibial and femoral tunnels prior to definitive second-stage revision anterior cruciate ligament reconstruction.

LEVEL OF EVIDENCE: Level IV, retrospective case series.