Becker's Spine Review

12 SPINE SURGEONS The Next 5 Years in the Spinal Fusion Arena By Anuja Vaidya Question: What are some trends we will see in spinal fu- sions over the next five years? Vladimir Sinkov, MD. Spine Surgeon at New Hampshire Orthopaedic Center (Nashua): More fusions will be done in a minimally invasive fashion and on an outpatient basis. Robotic tech- nology will make the procedures more accurate and streamlined. Mo- tion-preservation technology, such as disc and facet replacement de- vices, will also be used more frequently. As the population ages, their spines will age as well. is will lead to more need for spine surgeries overall. Scott Kutz, MD. Neurosurgeon at Texas Back Institute (Pla- no): A higher percentage of spinal fusions will be performed using minimally invasive techniques over the next five years. is will re- duce operative blood loss and time for recovery from spinal fusion surgery. is will allow for a higher percentage of patients to be treat- ed in ambulatory surgery centers. Greater use of intraoperative navigation and robotics technologies will be utilized to accomplish spinal fusions. is will allow for greater accuracy of instrumentation placement and greater safety with less radiation exposure to the patient and the surgeon and/or staff. Pre- operative plans will allow for design of patient-specific implants and instrumentation prior to surgery. I foresee greater usage of alternate materials that will enhance the bio- chemical interactions at the implant/bone interface to improve fusion rates and accelerate time to fusion. Greater usage of 3-D printed cus- tomizable implants will occur which will allow implant size, shape and modulus of elasticity to be much more patient-specific. Ram Mudiyam, MD. Spine Surgeon at Hoag Orthopedic Institute (Irvine, Calif.): Since the first description of spinal fusion using autogenous bone by Albee (tibial struts) and Hibbs (spinous processes) in 1911, there have been tremendous advances made in the art and science of spinal fusion techniques. Although autogenous bone gra (iliac crest, local bone) remains the "gold standard," limited supply, donor site morbidity, variable bone quality and host factors have led to an explosion in research and devel- opment of alternatives to autogenous bone. is is especially relevant in long segment spinal fusions (spinal deformity) and revision cases. ese have ranged from synthetic gra extenders (ceramic, bioglass, tricalcium phosphate), a variety of donor bone products (cortical, cancellous, structural allogras, demineralized bone matrix, stem cell based technologies) to bone morphogenetic protein. At the present time, there is a paucity of relevant clinical data demonstrat- ing the efficacy of one synthetic or DBM product over another. While BMP does enhance the rate of fusion, there have been safety concerns with its use in the cervical spine and around exposed neural elements. Over the next five years, there will be an increasing emphasis on stan- dardization of the plethora of bone gra products currently available based on high level evidence of efficacy in the clinical setting. Basic science research will continue to be focused on improved stem cell technology, host bone optimization (teriparatide) and alternative, and perhaps safer, forms of BMP. Advances in implant design such as na- no-surface technology and 3-D printing may help create a favorable environment for gra incorporation. Finally, "fusionless" spine surgery using growth modulation such ver- tebral body stapling in skeletally immature idiopathic scoliosis has shown early promising results in select cases. Payam Farjoodi, MD. Spine Surgeon at Center for Spine Health at Orange Coast Memorial Medical Center (Foun- tain Valley, Calif.): ere will be technical advancements in spinal fusion surgery; however, I think the biggest shis will come in how surgeons approach spinal fusion. Just as we have learned to focus on pelvic parameters in order to improve patient outcomes, new research will help us better classify surgical candidates and more appropriately determine the type and extent of spinal fusions for these patients. Plas T. James, MD. Spine Surgeon at Atlanta Spine Insti- tute: I think for spinal surgery there's technology coming along like navigated spine surgery, using interoperative CAT scans and more. ere's even a process where you can use overhead light to navigate instrumentation placement. As long as you can make it safer, that's the key to the future of spinal surgery. Brian R. Gantwerker, MD. Founder of the Craniospinal Center of Los Angeles: Overall, there will be more deformity work being done from an inpatient standpoint. In terms of one-and two-level fusions, the overall level will decrease. ere are always studies being published questioning the use of this technique in sin- gle-level settings without instability or subluxation. e data, be it good or junk, will be there. One of my favorite cranial neurosurgeons who I had the honor of working with a little, Dr. Robert Spetzler, would always ask "what's the denominator?" In other words, we should always be dubious of studies where the attrition rate is high or the number of patients being followed more than three months suffer from "the dwindles." In order to support the use of fusion in short segment stenosis and other widely accepted indications, we have to question the studies and look at them critically. at being said, we also have to be honest with ourselves, and not ignore good data just because we don't like what it shows. Kern Singh, MD. Co-Director of Minimally Invasive Spine Institute at Midwest Orthopaedics at Rush (Chi- cago): Spinal fusions have become common treatment methods for different spinal disorders. More recently, degenerative disc dis- ease and stenosis have been treated under the umbrella of spinal fusion. The improvements caused by these procedures can lead to significant improvements in regular activities that can be per- formed after treatment. The number of spinal fusions performed will certainly increase along with the number of indicated patients in the growing elderly population. However, spinal fusion is not al- ways preferred over disc replacement because of the diminishment in patients' mobility. Considering this advantage, disc replacement could become more prominent in upcoming years if it is proven to have lower risks of adjacent segment disease. n

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