CT-free Knee Replacements



A First in Texas with Robotic–assisted Platform

Over the years, knee arthroplasty has advanced beyond the limited world of cutting jigs, guides, and drills with the introduction of imaging, custom implants, and new robotic technology. Now a robotic–assisted knee surgery platform eliminates the need for a preoperative CT scan and combines intraoperative planning software with robotics for increased precision and accuracy during device implantation.

Partial knee replacements have been done with the system for several years, according to Raul A. Marquez, MD, an orthopedic surgeon at Cornerstone Regional Hospital in Edinburg. But recently the platform has been adapted for total knee replacements. One notable advantage of the system to patients is avoiding unnecessary imaging. Another possible benefit is improved accuracy and precision for the surgeon, which could mean better patient outcomes*.


How Does It Work?

The NAVIO Surgical SystemTM consists of a unique hand-held robotic bone-shaping device and a so-called “CT-free” navigation software platform. “When doing knee replacements, CT scans are usually required before surgery,” Marquez said. “Using this new system, we can digitally collect patient-specific data to build a 3-D model of a patient’s knee during the actual procedure.” The NAVIO intraoperative planning software maps the bone surface to get a 3-D representation of the bone structure. Advanced planning software allows the surgeon to virtually position the implant before it is actually implanted, creating a customized solution for each patient.


Technology that Fits

Robotic assistance comes from the handheld tool, and computer navigation tracks the position of the hand piece relative to the bone surface. The surgeon uses the tool to remove diseased bone, making way for the implant.

“The human eye cannot detect a 3- or 4-degree difference, but this tool can,” Marquez said of the tool’s accuracy. “Patients are more comfortable when we use this because they know their implant is custom measured just for them, which greatly reduces the chance of improper fit.”


Both Partial and Full Knee Replacements

Marquez has been using the system on unicompartmental knee arthroplasty (partial knee replacements) since 2014. The device received FDA marketing clearance for total knee arthroplasty in July 2016 and Marquez did his first full knee replacement in June 2017. It was the first total knee replacement performed in Texas without the need for a CT scan. “This system allows me to easily convert a partial knee replacement to a full knee replacement, depending on the patient’s needs,” Marquez added. Converting from a partial to a full knee replacement is not as involved with the new platform compared to traditional knee arthroplasty, he said.


mchine1Faster Recovery Time

Both partial and full knee replacement surgeries are done using a minimally invasive technique. Marquez said that the incision to insert the implant is smaller than traditional knee surgery. “Recovery can take one-third less time because there is less soft tissue dissection and patients can get up the same day and walk,” he said, adding that patients are usually out of the hospital after two days with no need for inpatient rehabilitation. “Patients go directly to outpatient physical therapy for four to six weeks.”




Get More Information

If you are a potential candidate for partial or total knee replacement surgery, you owe it to yourself to learn about your options. For more information about robotic knee replacement surgery at Cornerstone Regional Hospital, please call (956) 618-4444 or visit cornerstoneregional.com/robotic. Marquez offers free seminars on robotic total knee replacement surgery. See the events page on the website for upcoming seminar dates and times.




*Individual results may vary. There are risks associated with any surgical procedure. Talk with your doctor about these risks to find out if robotic surgery is right for you.


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