Spinal fusion is among the most commonly performed orthopedic surgeries in the United States, with more than 400,000 patients undergoing the procedure each year. Although most cases are successful, as many as 45 percent of patients experience complications after the operation, often resulting from the bone’s inability to tolerate the hardware surgeons use to support the skeleton. 

The most widely used technology to evaluate patients’ bones before spine fusion surgery is called dual x-ray absorptiometry, or DXA. DXA imaging gives physicians a rough sense of the strength of a person’s bone, but it is not foolproof. In some cases, surgeons find that patients whose DXA scans appear normal have bones that are so weak that the appliances they use during spinal fusion are at risk of failure. 

The HSS researchers hypothesized that a more sensitive measure of bone quality could identify abnormalities in the skeleton that DXA does not detect, and that these defects would be linked to postoperative complications. 

For the new study, the team led by Emily Stein, MD, an endocrinologist and bone specialist, along with spine surgeons Han Jo Kim, MD, Matthew Cunningham MD, PhD, and Frank Schwab, MD, turned to a cutting-edge technique for assessing bone called high-resolution peripheral quantitative computed tomography (HR-pQCT). HR-pQCT can separately measure how much bone is in the outer (cortical) and inner (trabecular) compartments and measure on a microscopic level how the inner trabecular bone network is organized, including the number, thickness and spacing between the parts of that network called trabeculae. These measurements—known broadly as the microarchitecture—may provide a much more robust assessment of skeletal health than DXA, particularly in this population of patients who frequently have changes in the area of the fusion which undermine the utility of DXA. 

“DXA provides a two-dimensional measure of bone density, or the amount of bone present, whereas HR-pQCT provides a true three-dimensional measurement of the bone density,” Dr. Stein said. “This provides additional information about the structural features of bone that can be leading to weakness or fragility.”

The study included 54 men and women scheduled for spinal fusion at HSS between December 2017 and December 2019. Patients underwent conventional DXA scans, as well as HR-pQCT scans of the radius (forearm) and leg bone (tibia).

Of the 54 patients in the study, 14 experienced complications within the first six months of surgery, including broken rods, loosened bone screws, fractures and abnormal bending of the spine. Although the number of people in the study was small, the researchers found that those with abnormalities on HR-pQCT were significantly more likely to experience complications than those without such defects -- abnormalities that were not evident on DXA imaging. These abnormalities involved lower bone mineral density in the trabeculae (the spongy tissue in the center of bones), fewer and thinner trabeculae, as well as thinner cortices.

“We used HR-pQCT to show for the first time that abnormalities in the microscopic structure of bone are directly related to the development of complications after fusion. Our study identified several abnormalities in patients who had complications,” Dr. Stein said.

For the moment, HR-pQCT is a research tool that’s not widely available to surgeons. “I think that it does provide a lot of additional information that we’re not getting from DXA. On DXA, the spine is almost always going to look fine, which can be misleading,” noted Dr. Stein. 

Dr. Stein’s group is expanding their study to include more patients. “Spinal fusion surgeries are so invasive, the potential for complications is high,” she explained. “We want to have the most optimal strategies for lowering complications in our patients, and that begins with understanding who is at risk and why. In our future work with additional patients, we hope to be able to define which features, or group of features of the bone structure is most important in contributing to surgical success. This will help us to devise the most targeted treatment strategies for our patients.”

Dr. Stein's team published their findings in the journal Bone, and made available online first on November 4, 2020.

The HSS Innovation Institute, the commercialization arm of HSS, transforms novel ideas and HSS knowledge within the field of musculoskeletal health into technologies, products and solutions that improve people’s lives. In his new role, Dr. Schwab will advance the institution’s culture of innovation by advancing the bridge between clinician-scientists, industry partners and the Innovation Institute, which has recruited engineers, business analysts, lawyers and industry leaders who are experts in product development, patent protection, licensing, entrepreneurial activities and commercialization.

“The HSS Innovation Institute is how we are harnessing our advanced medical expertise, vast experience with complex care, and our 20 research laboratories, to create even better possibilities for musculoskeletal health worldwide,” said Bryan T. Kelly, MD, Surgeon-in-Chief and Medical Director at HSS. “Dr. Schwab’s leadership will help ensure that we fulfill our responsibility and opportunity to improve the treatment of conditions which affect more than 127 million Americans each year.”

“We are honored to welcome Dr. Schwab to the Innovation Institute team,” said Leonard Achan, RN, MA, ANP, Chief Innovation Officer at HSS. “As a clinician-scientist and an inventor, he understands the importance of building an infrastructure that continues to support our longstanding history of pioneering and commercializing innovations.”

“I am looking forward to partnering with our innovation team, our clinicians, scientists and staff to leverage the work that has been done over the last several years,” said Dr. Schwab. “Trust and value creation are key components to success. My goal is to further develop an environment where innovators trust and understand the value and expertise that the HSS Innovation Institute brings to the table — we are not just a tech transfer department, but an enthusiastic team that will guide them through the patent, regulatory and prototyping processes to become commercially successful.”

Dr. Schwab was a founder of Nemaris, Inc., which developed dedicated spine measurement and surgical planning software used by physicians and researchers across the world and successfully merged with a global industry partner. He was a board member of the Scoliosis Research Society, served on several key committees and has won multiple awards for spine deformity research. Additionally, he is a leader and board member of the International Spine Study Group. Over the course of his career, Dr. Schwab has received multiple grants, published more than 200 original and review articles and given more than 400 presentations at scientific conferences. He remains committed to the education of students, researchers, residents and fellow surgeons, with an absolute focus on providing the very best care to patients.

“Leveraging the knowledge and clinical expertise of our physicians, researchers and engineers has helped HSS create value-based and patient-centered healthcare solutions for more than a century,” said Louis A. Shapiro, HSS President and CEO. “Together, Dr. Schwab and the entire innovation team will provide support to HSS innovators and other physician-scientists who have ideas ready to become impactful contributions to musculoskeletal health.”

Drs. Sandhu and Sama succeed Frank Schwab, MD, who will continue his practice as chief emeritus of HSS Spine. Under Dr. Schwab’s leadership, HSS Spine continued to advance its clinical and academic reputation and bolstered its position as the international leader in complex and minimally invasive spine procedures.

“HSS is world-renowned for its innovative and research-based evaluation and treatment of people with all levels of musculoskeletal disease and injury, including afflictions of the spine,” said Bryan T. Kelly, MD, surgeon-in-chief and medical director at HSS. “We look forward to Drs. Sandhu and Sama’s leadership to continue to elevate our spine program to even higher levels of patient care excellence.”

“HSS has been ranked the # 1 Orthopedic program for 10 consecutive years. Our spine service is a key part of that amazing achievement and is one of the best in the world,” said Louis A. Shapiro, president and CEO at HSS. “The combined leadership and experience of Drs. Sama and Sandhu will take us to the next level.”

Dr. Sandhu focuses on minimally invasive spine surgery, microsurgery, computer-assisted surgery and spinal biologics. Previously chief of the spinal service at UCLA, and a graduate of Northwestern University Feinberg School of Medicine, Dr. Sandhu joined HSS in 1997. He is actively engaged in the research, development and invention of a variety of devices and instruments and holds several patents on the diagnosis and treatment of spinal disorders.

“HSS is unique in that we have a bench-to-bedside approach and are able to directly translate our innovative research into appropriate and customized patient care,” said Dr. Sandhu. “Sometimes this means not doing surgery when you don’t need to. Other times it means ensuring the right kind of procedure. I am looking forward to this new opportunity to build on the strong foundation of our service and continue our mission to provide the highest quality spine care.”

Dr. Sama specializes in the evaluation and surgical management of all traumatic, degenerative and deformity-related conditions of the spine. A member of numerous spine and orthopedic societies, he lectures at scientific conferences internationally. He is also involved in innovative product development, helping to design orthopedic implant devices for spinal surgery. A graduate of the University of Miami, Dr. Sama completed his fellowship at HSS before beginning his practice in 2001.

“I am honored to co-lead our dedicated multidisciplinary team, who are so experienced that complex procedures have become routine,” said Dr. Sama. “Our high volume and incredible team allows us to continue to advance our expertise, leading to optimal patient care and outcomes.”

According to the article, the chemical composition of spinal discs changes and retains less water as people age.

"We all lose some of the water content in the disc, so the discs settle down. And if you think of the whole spinal column, and you think just a few millimeters but across an entire spine, it all adds up, so we get shorter with age," said Dr. Schwab.

"You can't change your genetics. Some people will get shorter faster than others, and some people will be curved forward more than others. It's very hard to change that," Dr. Schwab added.

To help prevent osteoporosis, Dr. Lane recommended taking vitamin D and calcium.

Read the full article at nexttribe.com.

A pain management institution is conducting a clinical trial to evaluate a new spinal cord stimulator. According to the segment, this procedure provides relief by sending electrical waves throughout the spinal cord and blocking pain signals to the brain.

Billups interviewed HSS chief of Spine Service Frank Schwab, MD, who offered his perspective on spinal cord stimulation.

"Many patients come and are considering dorsal column stimulation in lieu of surgery, or in lieu of other treatments. But if there is a clearly diagnosed problem that can be treated or fixed definitively with another procedure, then I think that's probably a better approach."

This segment originally appeared at ny1.com. This aired during the January 3, 2018 broadcast.