Bone morphogenetic protein in complex cervical spine surgery: A safe biologic adjunct?

The advent of recombinant DNA technology has substantially increased the intra-operative utilization of biologic augmentation in spine surgery over the past several years after the Food and Drug Administration approval of the bone morphogenetic protein(BMP) class of molecules for indications in the lumbar spine. Much less is known about the potential benefits and risks of the "off-label" use of BMP in the cervical spine. The history and relevant literature pertaining to the use of the "off-label" implantation of the BMP class of molecules in the anterior or posterior cervical spine are reviewed and discussed. Early prospective studies of BMP-2 implantation in anterior cervical spine constructs showed encouraging results. Later retrospective studies reported potentially "life threatening complications" resulting in a 2007 public health advisory by the FDA. Limited data regarding BMP-7 in anterior cervical surgery was available with one group reporting a 2.4% early(< 30 d) complication rate(brachialgia and dysphagia). BMP use in the decompressed posterior cervical spine may result in neurologic or wound compromise according to several retrospective reports, however, controlled use has been reported to increase fusion rates in select complex and pediatric patients. There were no cases of de novo neoplasia related to BMP implantation in the cervical spine. BMP-2 use in anterior cervical spine surgery has been associated with a high early complication rate. Definitive recommendations for BMP-7 use in anterior cervical spine surgery cannot be made with current clinical data. According to limited reports, select complex patients who are considered "high risk" for pseudoarthrosis undergoing posterior cervical or occipitocervical arthrodesis or children with congenital or traumatic conditions may be candidates for "off-label" use of BMP in the context of appropriate informed decision making. At the present time, there are no highlevel clinical studies on the outcomes and complication rates of BMP implantation in the cervical spine.

Background,techniques,applications,current trends,and future directions of minimally invasive endoscopic spine surgery:A review of literature

Across many of the surgical specialties,the use of minimally invasive techniques that utilize indirect visualization has been increasingly replacing traditional techniques which utilize direct visualization.Arthroscopic surgery of the appendicular skeleton has evolved dramatically and become an integral part of musculoskeletal surgery over the last several decades,allowing surgeons to achieve similar or better outcomes,while reducing cost and recovery time.However,to date,the axial skeleton,with its close proximity to critical neural and vascular structures,has not adopted endoscopic techniques at as rapid of a rate.Over the past decade,increased patient demand for less invasive spine surgery combined with surgeon desire to meet these demands has driven significant evolution and innovation in endoscopic spine surgery.In addition,there has been an enormous advancement in technologies that assist in navigation and automation that help surgeons circumvent limitations of direct visualization inherent to less invasive techniques.There are currently a multitude of endoscopic techniques and approaches that can be utilized in the treatment of spine disorders,many of which are evolving rapidly.Here we present a review of the field of endoscopic spine surgery,including the background,techniques,applications,current trends,and future directions,to help providers gain a better understanding of this growing modality in spine surgery.