North American Spine Society, Oct. 14-17
The annual meeting of the North American Spine Society was held from October 14 to 17 in Chicago and attracted approximately 5,000 participants from around the world, including orthopedic surgery, neurosurgery, neurology, radiology, and anesthesiology specialists, as well as researchers, physical therapy specialists, and other spine care professionals. The conference featured presentations focusing on the latest advances in medical and surgical spine care.
In one study, David Bumpass, M.D., of Washington University in St. Louis, and colleagues found that patients who underwent multi-level posterior cervical fusions (three or more cervical levels) that stopped distally at C7 had similar clinical and radiographic outcomes to patients whose fusions extended across the cervicothoracic junction to the upper thoracic spine. The investigators found no differences in re-operation rates for revision surgery, and no differences in complications. Patients whose fusions stopped at C7 experienced less intraoperative blood loss.
"The key conclusion is that there does not appear to be dramatic differences in outcomes between these two groups of cervical fusion patients, at short-to-midterm outcomes (minimum follow-up was one year and mean follow-up was three years)," Bumpass said. "Based on the findings of this initial retrospective study, we are initiating a prospective study to provide high-level evidence-based guidelines for selection of the distal level for these long cervical fusions."
In another study, Dageng Huang, M.D., of Honghui Hospital at the Xi'an Jiaotong University Health Science Center in China, and colleagues compared the effectiveness of allograft and autograft in atlantoaxial fusion and assessed the feasibility of using allograft for atlantoaxial fusion by computed tomography (CT) imaging and dynamic radiographs.
The investigators found that allograft was not reliable for posterior atlantoaxial fusion in an onlay fashion, even with the rigid internal fixation of modern construct. They also found that autograft is still the gold standard for atlantoaxial fusion despite its donor site morbidity and the fact that the assessment of fusion based on lack of movement on dynamic radiographs is not reliable.
"Confirmation of fusion should be based on the presence of bridging bone on CT imaging," Huang said. "We suggest not using allograft for fusion when you do atlantoaxial posterior fusion without decortication of C1-2 joints."
During an additional presentation, Adam Jakus, Ph.D., of the Simpson Querrey Institute for BioNanotechnology at Northwestern University in Chicago, provided insight into two new approaches to the design and fabrication of three-dimensional (3D)-printable materials that can be utilized to create new biologic materials for tissue engineering and regenerative medicine, including 3D-Painting and PEGX Bioprinting. Jakus provided a cursory overview of several of the new biologic materials produced using these two new 3D-printable material design approaches.
"For the 3D-Painting side of things, I presented two promising new 3D-printable biomaterials/biologics: The osteogenic Hyperelastic 'Bone,' so named because it is highly elastic in nature despite being comprised of 90 weight percent bioceramic, and the electrically conductive and highly neurogenically bioactive 3D-Printed Graphene," Jakus said. "For the PEGX Bioprinting side of things, I briefly demonstrated that this new process can be used to make more than 100 3D-printable natural, synthetic, and natural-synthetic hybrid bioinks that can be 3D-printed with or without encapsulated cells."
Overall, the presentation demonstrated that it is possible to take comprehensive approaches to the design of 3D-printable biomaterials.
"By understanding the nature of '3D-printability,' it is possible to rapidly engineer a wide variety of biologic inks and resulting 3D-printed biomaterials for both hard (bone and dental) and soft (every other tissue and organ) tissue engineering and regenerative medicine applications," Jakus said. "We believe that these new 3D-Painting and PEGX Bioprinting technologies will have significant and far-reaching clinical impacts for hard and soft, simple and complex, tissue and organ repair, regeneration, and replacement. Not only are they proving to be highly efficacious in terms of biological function, but the fact that they result in surgically friendly (easy to handle and manipulate) materials that can be rapidly produced makes their clinical implementation in the coming years realistic."