Penn State Health Spine Center Performs Spine Surgery With Unmatched Precision Using the Mazor X Stealth Edition Robotic Guidance System

By Thomas Crocker
Thursday, May 7, 2020

The Penn State Health Spine Center at Penn State Health Milton S. Hershey Medical Center is transforming spine surgery in central Pennsylvania with the Mazor X Stealth Edition by Medtronic, a robotic guidance system that allows neurosurgeons to plan and execute open and minimally invasive spine surgeries with unprecedented accuracy, producing a bevy of benefits for patients.

Featuring advanced surgical planning software, a robotic arm that acts like a surgical assistant and intraoperative navigation that ensures faithful execution of the surgeon’s plan for the procedure, the Mazor X Stealth Edition is the latest, most sophisticated manifestation of spine surgery’s evolution toward increased precision, minimal tissue disruption and outcomes that meet or exceed those of nonrobotic procedures. The Penn State Health Spine Center began using the Mazor X Stealth Edition last spring and is the only center between Philadelphia and Pittsburgh with this technology.

“Just as technology is advancing in society, so, too, is it advancing in medicine, and surgical care is keeping pace,” says Michael Sather, MD, FAANS, director of Epilepsy Surgery at Penn State Health Neurosurgery and associate professor of Neurosurgery at Penn State College of Medicine. “The Mazor X Stealth Edition allows us to provide care that maximizes patient safety and surgical efficiency, resulting in less operative time, a lower risk for infection, less anesthesia time and faster recovery. We want to continue to be the leaders in central Pennsylvania by offering the most advanced techniques and treatments for spine conditions, and the Mazor X Stealth Edition is the foremost technology available in terms of robotics and live navigation.”

Penn State Health Spine Center neurosurgeons mostly use the Mazor X Stealth Edition to perform open or minimally invasive surgeries that require placement of spinal instrumentation, such as lumbar and thoracic spinal fusions to treat degenerative disc disease, fractured vertebrae, tumors, scoliosis, spinal stenosis or spondylolisthesis. The neurosurgeons also use this technology to assist with decompressions that do not require instrumentation and with obtaining biopsies of lesions.

The ability to streamline the precise planning of the placement and trajectory of pedicle screws for fusions has important implications for long-term back health.

“The Mazor X Stealth Edition allows me to plan where I will make my incisions so I can minimize their size,” says Tim Reiter, MD, director of Spinal Surgery at Penn State Health Neurosurgery, associate director of the Penn State Health Spine Center and associate professor of Neurosurgery at Penn State College of Medicine. “The less muscle I cut, the better it is for patients. Cutting muscle basically destroys it because it becomes scar tissue. Losing muscle in the spine means losing support, which can lead to back pain because the spine doesn’t have stability from muscle anymore. That can be devastating for patients.”

Creating a Surgical Plan

The key to every operation using the Mazor X Stealth Edition is presurgical planning, which can occur on the day of surgery or several days in advance. After the patient undergoes a CT scan, the image loads into the software, which creates a 3D model of the individual’s spine, allowing the surgeon to tailor the operation to the patient’s unique anatomy.

“For a spinal fusion using the 3D model of the patient’s spine, I can use my computer or the Mazor X Stealth Edition workstation to plan where I want the instrumentation to go, where to make the incisions and which implants to use,” says J. P. Kelleher, MD, assistant professor of Neurosurgery at Penn State College of Medicine. “This ensures that my incisions align according to the instrumentation and the screw heads align to each other, and it allows me to determine how much to bend the rods.”

The Mazor X Stealth Edition moves presurgical planning out of the OR, which makes the surgery more efficient.

“The Mazor X Stealth Edition enables minimally invasive spine surgery by streamlining the process for the surgeon with software-based presurgical planning,” Dr. Sather says. “That decouples some of the planning time from the operation, meaning I can decide where to put the screws and other hardware days or weeks in advance.”

The Mazor X Stealth Edition software allows the surgeon to view the patient’s spine in three planes of imaging — an invaluable capability when planning where to insert and place each screw. Using the 3D model, the surgeon can perform the operation virtually, placing the screws and connecting rods with pinpoint accuracy.

“When implanting instrumentation, we’re dealing with millimeters of accuracy,” Dr. Kelleher says. “Accurate presurgical planning and real-time navigation during the procedure reassures both patient and surgeon and can lead to better outcomes.”

Performing the Procedure

In the OR, the Mazor X Stealth Edition robotic arm attaches to the end of the surgical bed and connects to a mobile workstation with a screen for visualization. The surgeon affixes the robot to the patient, often using a percutaneous pin inserted in the pelvic bone. The robotic arm scans the patient to register where the patient is in space and orient itself.

“We take two X-rays of the patient, and the Mazor X Stealth Edition syncs the patient’s CT scan to those X-rays,” Dr. Reiter says. “That allows the surgeon to toggle between the preoperative CT and the X-rays to confirm that the robot is following the plan.”

The surgeon directs the robotic arm to place each screw according to a predetermined trajectory.

“I don’t have to think about placing the screws. I can just plan where to put them and insert them,” Dr. Reiter says. “In a fusion and decompression, the hard part of the surgery that I want to concentrate on is opening up around the nerve roots, and then I can finish the fusion by putting bone graft down, placing the bars and screw heads, and locking down the screws. What I really want to be thinking about is decompressing and protecting the nerves. With the robot, inserting the screws becomes almost automatic. The robot does those tasks for me.”

StealthStation navigation technology — the new aspect of the Mazor X Stealth Edition — allows the surgeon to track the instrumentation’s every millimeter of movement.

“When I put an instrument in, I’m able to see on the workstation monitor the bony anatomy I’m working on,” Dr. Sather says. “That adds an extra level of confirmation.”

Dr. Reiter agrees.

“I’ve been very pleased with the accuracy of the screw placement,” he says.

How Patients Benefit

The enhanced surgical precision that the Mazor X Stealth Edition affords may be its greatest benefit for patients, but it is far from the only one. This technology significantly reduces radiation exposure for patients, surgeons and OR personnel, as it requires only two X-rays at the beginning of the procedure for the robot to register the system. In nonrobotic spine surgeries, the surgeon may need up to two or three X-rays per screw to check its location, according to Dr. Reiter. Patients have a lower risk of infection, shorter hospital stays and less postoperative pain.

“Our outcomes with the Mazor X Stealth Edition have been great,” Dr. Kelleher says. “The improved pain relief that patients experience and their ability to return to activities sooner benefit everyone. Patients use far fewer narcotics than with an open, nonrobotic procedure, which is especially important in the context of the opioid epidemic. In many cases, over-the-counter medication is enough to help relieve discomfort.”

Dr. Kelleher wants referring physicians to know their patients do not need to leave central Pennsylvania to undergo advanced spine surgery.

“The Penn State Health Spine Center has the best surgical technology on the market,” he says. “We had the community in mind when we acquired the Mazor X Stealth Edition. We want to provide the best resources to treat our patients, and that’s what we have.”

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