Biomechanical and Radiographic Comparison of Demineralized Bone Matrix, and a Coralline Hydroxyapatite in a Rabbit Spinal Fusion Model

The use of bone grafts is an essential component in spinal fusion. Autologous bone has been shown to result in long-term stable arthrodesis between spinal motion segments. However, autograft can be associated with significant morbidity and a limited supply. Alternatives, such as allogeneic demineralized bone matrix (DBM), are a potential source and supplement to autograft bone. The current study compares the ability of a DBM product (BioSet® RT) and a coralline hydroxyapatite (Pro Osteon® 500R), for inducing spinal fusion in a rabbit model. BioSet® RT, alone or in combination with autograft, and Pro Osteon® 500R were implanted in the posterior lateral inter-transverse process region of the rabbit spine. The spines were evaluated at 18 weeks for fusion of the L4—L5 transverse processes using a total of 33 skeletally mature male rabbits; 4 naive animals were also included in the study. Samples were evaluated radiographically, histologically, by palpation, and through mechanical strength testing. Radiographi...