Becker's Spine Review

8 SPINE What could smart implants look like in spine? By Carly Behm I n the joint replacement space, Zimmer Biomet's "smart" knee implant takes the technology to a new level with the ability to track patient movement and recovery. Five spine surgeons discuss if that type of technology could eventually thrive in spine surgery. Editor's note: Responses were lightly edited for clarity and length. Question: How might "smart" implant technology, such as that used with Zimmer Biomet's PersonaIQ, be applicable in spine surgery? Brian Gantwerker, MD. e Craniospinal Center of Los Angeles: ere has been talk of smart implants for the last decade and a half or so. e Zimmer Biomet product PersonalQ analyzes gait metrics in knee implants. Active feedback implants are already being used. Spinal cord stimulators come fairly close to such technology. In future, spine surgery analyses of stresses and movement analysis within the implants themselves would provide tremendous feedback for study analysis and implant design. e obvious other side of this is personal privacy. People should not expect these devices to be immune from interrogation by other, non care-team actors, and also to have their data likely shared in large databases. Even with outputs, there are no guarantees that their personal information is safe. While the unquenchable thirst companies have for data is always there, patients need to realize what they are getting into if they have that technology in their bodies.e serious questions about confidentiality must be brought up before we start putting these things in patients. It seems more and more, we are becoming the society in "Blade Runner." Brian Fiani, DO. Mendelson Kornblum Orthopedic & Spine Specialists (West Bloomfield, Mich.): "Smart" implant technology, which uses sensor technology, could revolutionize the way we think about spine implant technology, specifically spinal interbody devices. If a company can incorporate personalized spinal biomechanics with customized fit for patients, then there would be a foreseeable shi towards its usage. e key to its function is kinematic data metrics and other physiological parameter measurement tools for patient monitoring and treatment post-surgery. Surgeon satisfaction would likely increase due to knowing the size/shape and fit of the implant preoperatively, and the implant could potentially help patient biomechanics with kinematic data postoperatively. eoretically the new implants could lessen postoperative pain and create higher patient satisfaction. I am optimistic about this technology, but it will take about five to 10 years to fully develop. Jeffrey Gum, MD. Norton Leatherman Spine (Louisville, Ky.): is technology without a doubt will be a very integral part of the future of spine care. is rationale can best be explained within a few different contexts. First, let's consider these under the value context. Spine care, especially surgery, is very expensive. is threatens a large target on spine surgery and emphasizes the need to demonstrate value, which is a ratio between cost/outcome. Smart implants have the potential to reduce costs associated with unnecessary diagnostic studies and postoperative visits. Information such as stress/strain on the instrumentation can be useful for fusion assessment, temperature changes could provide information with regards to infection, functional data has the potential to even help with diagnosis. We all know it has been a long time since we have made a big breakthrough with regards to diagnostics within the spine world. Lastly, we have come a long way with regards to outcome assessment. Decades ago, the outcome was assessed by the treating surgeon — either great or very great. We then progressed to patient perspective and are very beneficial but have inherent flaws such as subjectivity in the interpretation of the questions, response fatigue with numerous questionnaires, and confounding/co-existing pathology that is not spine related. In my opinion, our next step in outcome assessment is objective functional assessment such as distance walked, gait feedback, pace of mobilization, etc. All of these have the potential to reduce waste and unnecessary cost while improving outcome, which in turn improves the value equation from both perspectives. Vladimir Sinkov, MD. Sinkov Spine (Las Vegas): My idea of "smart" implants in spine surgery would be some kind of microscopic pressure sensors, chemical sensors, and accelerometers with wireless connectivity and a small and long-lasting power source that could be fitted inside an interbody spacer, pedicle screw, or a disc replacement device to provide data on mechanical loads, inflammatory or infection markers, and motion. is could help the surgeon to analyze when the fusion becomes solid, if there is evidence of micromotion and potential failed fusion, if there is evidence of focal inflammation or infection, or how well the disc replacement device is moving. e technological challenge would be to fit all of that technology inside the implant in a manner that is durable, safe to the patient, and does not interfere with the main mechanical function of that implant. at would be quite a significant challenge and will likely significantly increase the cost of such implants. e final challenge would be to demonstrate if the clinical benefits of having this real-time data justify the increased costs. Christian Zimmerman, MD. St. Alphonsus Medical Group and SAHS Neuroscience Institute (Boise, Idaho): "Personalized" and tailored care plans are the touchstone of spinal care delivery, which parallels joint replacement surgery and its continuum. Yet the same issues surrounding cost containment, failure rates and the mitigating circumstances involved in that care delivery remain; Post operative pain, both acute and chronic, pseudoarthrosis rates and adjacent level failure. As we do applaud the newest innovations surrounding joint replacement surgery from the standpoint of potential postoperative management issues, the strong case of economics in this environment inhibits many smart implants/new innovations from getting a foothold. e idea of capturing gait metrics and range of motion data assisting the more difficult patient during rehabilitation and forward conditioning is laudable. I find this intriguing from a recovery standpoint, as instructional adjustments throughout care delivery is warranted, especially in any instrumented setting. Obvious complexities of spinal motion, progressive disease patterns and vectorial wear must be considered in implementing a like product for the spine. n "While the unquenchable thirst companies have for data is always there, patients need to realize what they are getting into if they have that technology in their bodies.e serious questions about confidentiality must be brought up before we start putting these things in patients." — Brian Gantwerker, MD

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