Vertebral reconstruction with cortical allograft: long-term evaluation

Reconstruction of large anterior vertebral column defects is indicated in a number of pathological conditions including tumor, infection, trauma and p ost-traumatic deformity. Several substitutes and techniques are available f or the functional restoration of the vertebral column. Vascularized bone tr ansfers, autografts, allografts or xenografts have been used, as well as me tal or ceramic implants. All of these bear potential advantages and drawbac ks in terms of associated morbidity of graft harvesting, disease transmissi on, mechanical failure, implant incorporation and overall long-term clinica l outcome. In the present paper we report our experience with the use of fr eeze-dried, gamma-irradiated, cortical allograft for the reconstruction of large, anterior segmental defects of the spine, involving at least one vert ebral body with its two adjacent discs. Cortical allografts were used in 67 cases operated for a variety of conditions. No case of disease transmissio n, infection or long-term mechanical graft failure occurred in our entire s eries, with a mean follow-up of 31 months. Fusion and mechanical stability was reliably obtained. Specific advantages include the absence of donor sit e morbidity, the possibilities for exact trimming to the size of the defect , superior mechanical strength as compared to available autograft, and reli able fusion with the host bone with partial bone remodeling, preventing fat igue failure. We conclude that freeze-dried, irradiated cortical allografts are safe and effective for anterior reconstruction of the spine.