Baylor Scott & White Medical Center at Waxahachie officials showcased on Thursday their latest robotic technology that will improve results for patients undergoing partial knee replacements and total hip replacement surgery.

The robot, named SARA (Surgery Assisted Robotic Arm) by Waxahachie Global High students, joined the hospital in October. The total cost of the robot was $900,000.

Chris York, the Baylor Scott & White Medical Center President, said SARA has added another layer to the healthcare services that the hospital can provide to the community and it is being used on a weekly basis at the hospital.

“We were actually able to purchase this equipment through our donors. We are the first hospital in the Baylor Scott & White system to bring this to market. Dr. Roux is our champion to make this happen and to drive it. He was the passion behind this technology in wanting to bring a superior level of service to orthopedics to Waxahachie and Ellis County,” York said. “We are honored to be the first one in the healthcare system to provide this to our community. We are grateful for Dr. Roux’ leadership around this technology and the fact that he was really engaged in it and being the champion. It is amazing technology that we can bring to the community.”

“The robot is designed to help us with partial knee replacements as well as to fine-tune our good, safe practices for total hip replacement. So partial knee replacement is something that is not new in the orthopedic world. It has actually been present for quite some time,” said Marc Roux, an orthopedic surgeon. “But because of the nature of how a partial knee replacement works with your native knee, they were not performing well. They were failing too soon. They were not lasting long enough. So it was kind of hard to promise patients long-term results.”

Roux said with a partial knee replacement doctors were seeing that high failure rate inside of five years.

“The reason why they failed quite a bit is because if you are off just a little bit angle-wise or position-wise, your negative ligaments are going to fight that mechanical device,” Roux said. “If it fights that mechanic device, what we see is pain. We see limitation of range motion, limitation of activity and patient dissatisfaction. Then, we are going to have to convert it to a total knee.”

Roux said the technology has evolved so much it can now assist doctors. Before committing to a surgery, other options are explored and if surgery is the best option, a CT scan of the patient’s knee is done first.

“That plots that knee and that maps that knee. We then use that data to create a pre-operative plan,” Roux said. “In that pre-operative plan, we fine-tune in the operating room and you are under anesthesia and we have started the procedure. We fine-tune that plan by balancing the knee and balancing the ligaments of the knee. So that way we are putting the implant in a good marriage with the knee.”

During the surgery, SARA’s software allows the doctor to make adjustments as needed. The 3D model of the patient’s knee is displayed on a monitor next to the operating table. The area of bone the doctor is reshaping appears green on the screen. The robot’s program sets up a virtual wall so that the doctor can’t cut bone that does not need to be cut. Sensors are placed on the body, telling the doctor where the implant needs to be to make a perfect fit.

During the operation, the doctor, surgical staff and the robot’s technician work together to make sure that everything goes smoothly. If an issue comes up with the robot, the technician can troubleshoot and resolve the issue.

“The robot helps me execute that plan with a margin of error that is less than a millimeter. The way the robot works unlike other robots is that it is scrubbed in with me. It is a sterilized robotic arm that is manually manipulating. It is keeping me constrained through our plan,” Roux said. “The monitor is used as a tool. So if we go past those parameters, there is a virtual wall. So it will kind of bump and won’t let me push past that wall. If I try to manually override that, then the robot senses that and cuts the motor. It won’t let you cut something that you are not suppose to cut.”

Roux said the robot allows doctors to do minimum invasive procedures reducing soft tissue and bone trauma. The pain is less and the swelling post-op is less, the blood loss is less and the recovery is faster. Procedures with the robot take about an hour to complete for a partial knee replacement.

Roux said a total knee replacement is a much more daunting task.

“The difference between a partial and a total is that we are maintaining all of the ligaments in the knee. It is a little less invasive, and a little easier recovery. It is about the third of the rehab time, a third of the productivity time,” Roux said. “Just the snapshot of the patients that we have done over the last six months includes manual laborers and office-type workers. Those manual labors we have not had one that has been out of work for most of six weeks, where a total knee replacement is three to four months.”

York said the robot works in a similar manner for hip replacements.

“It is the same concept. You’re just taking a different joint. As opposed to the knee, you are looking at the hip. You do imaging studies on the front end,” York said. “You go through the entire anatomy of the patient and make sure that you are creating the best scenario for them post-operatively. Then, literally step-by-step, the robot and the surgeon work in tandem to create that optimal implant. “

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