David Chandler, MD, an orthopedic spine specialist at Gulf Breeze, Fla.-based Andrews Institute for Orthopaedics & Sports Medicine, reviewed the last 30 years of spine surgery innovation, offering insights into an array of advancing technologies in an interview for Andrews' Institute.
Note: Transcript was edited for style.
Dr. David Chandler: Thirty years ago, we had limited instrumentation to correct and stabilize spinal deformities and instabilities. Around that time, we began using pedicle screws, which are screws placed into a column of bone connecting the back of the spine to the front. There was some initial controversy about the procedure, but pedicle screws provided superior fixation and correction in situations that could not be managed by previously available instrumentation. Subsequently, we also discovered the adverse effects of rigid fixation in a spinal fusion with accelerated degeneration and instability at adjacent spinal levels. Unfortunately, over the past 30 years, [while] there has been a concerted effort in advancing instrumentation with increased utilization [there's been] little improvement in patient outcomes.
In response to the appreciation of this accelerated spinal degeneration next to spinal fusions, there was interest in developing motion-preserving technologies. One of these new technologies is total disc replacement, which was designed to address back pain resulting from painful disc degeneration. There are narrow criteria for TDR, but the procedure has improved long-term outcomes and diminished adjacent segment degeneration compared to patients undergoing fusion for the same problem.
Kyphoplasty is another procedure introduced to address painful compression fractures for which we had no effective treatments to expedite pain relief and improve the course of the disease. During the 1990s, physicians in France began pressurized injections of bone cement into a fractured spine bone. A refinement of this procedure in the U.S. added the placement of balloons into the broken bone. This addition allowed for correction of the deformity and created a cavity for injection of thicker bone cement at lower pressure. The improved injection technique provided better control of cement flow and less unwanted cement leakage. This procedure is still controversial, as are so many things in the treatment of spinal conditions.
Another exciting area of development is performing nerve cauterization in the center of the vertebra for patients with back pain. A pilot study several years ago in Europe evaluated a procedure to burn nerves in the center of the bone to help to decrease the back pain. Recent approval recently allows for application in the U.S.
Spine surgery is better at relieving limb pain from nerve compression than it is for relieving neck and back pain. Research continues to explore new interventions with different techniques, medications and therapies.
Research in device development continues, but over time, there is probably going to be an evolution away from the focus on the use of instrumentation to [increased use of] biologic interventions. Currently, [surgeons use biologics including] platelet-rich plasma and, now, stem cells [in spinal fusion procedures]. Biologics development and utilization is an area of ongoing research. Currently, there is a broad application of biologics with several practitioners making promises on which they can't deliver, and which are not supported by sound, rigorous science.
Finally, we have improved the way physicians and patients interact to select a treatment that is appropriate for the patient; one must always consider the natural history of the disease and weigh the risks of proposed interventions. Shared decision-making and patient engagement have also advanced over the last 30 years; now, there is more sharing of knowledge to help the patient understand and assist them in making the decision that is best for them.
Andrews Institute has a video series featuring its clinicians talking about an array of orthopedic and spine-related topics. View the series here.