Spine fusion is a tool used in the treatment of spine trauma, tumors, and degenerative disorders. Poor outcomes related to failure of fusion, however, have directed the interests of practitioners and scientists to spinal biologics that may impact fusion at the cellular level. These biologics are used to achieve successful arthrodesis in the treatment of symptomatic deformity or instability. Historically, autologous bone grafting, including iliac crest bong graft harvesting, had represented the gold standard in spinal arthrodesis. However, due to concerns over potential harvest site complications, supply limitations, and associated morbidity, surgeons have turned to other bone graft options known for their osteogenic, osteoinductive, and/or osteoconductive properties. Current bone graft selection includes autograft, allograft, demineralized bone matrix, ceramics, mesenchymal stem cells, and recombinant human bone morphogenetic protein. Each pose their respective advantages and disadvantages and are the focus of ongoing research investigating the safety and efficacy of their use in the setting of spinal fusion. Rh-BMP2 has been plagued by issues of widespread off-label use, controversial indications, and a wide range of adverse effects. The risks associated with high concentrations of exogenous growth factors have led to investigational efforts into nanotechnology and its application in spinal arthrodesis through the binding of endogenous growth factors. Bone graft selection remains critical to successful fusion and favorable patient outcomes, and orthopaedic surgeons must be educated on the utility and limitations of various biologics in the setting of spine arthrodesis.
Department of Orthopaedic Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL
Wellington Hsu is a paid consultant for AONA, Bioventus, Globus Medical, Lifenet, Medtronic Sofamor Danek, Pioneer, Stryker, and Synthes. He is a board or committee member for the American Academy of Orthopaedic Surgeons, the Cervical Spine Research Society, the Lumbar Spine Research Society, and the North American Spine Society. He is on the editorial board of the Journal of Spinal Disorders and Techniques. The other authors have no conflict of interest to declare.
Reprints: Wellington K. Hsu, MD, Department of Orthopaedic Surgery, Feinberg School of Medicine, Northwestern University, 676 N. St. Clair St., #1350, Chicago, IL 60611 (e-mail: wkhsu@yahoo.com).
Received March 23, 2015
Accepted April 13, 2015