Robotics comes to knee replacement surgery
Orthopedic surgeon Paul Dimond, MD has changed the way he does knee replacements, using a new robotic system called ROSA® Knee System.
After 26 years performing knee replacement surgery using the traditional method of surgical instruments, he recently trained on the ROSA robotic assistant technology and he was sold on its effectiveness.
“I held out for a number of years from using robotics in my surgeries and continued doing instrumented knee replacement surgeries,” said Dr. Dimond, who practices at Falmouth Hospital. “Once I took the ROSA robotic course, I was incredibly impressed and decided to do total knee replacement surgery using ROSA going forward. I have been very happy with the early outcomes of robotic surgery.”
Falmouth orthopedic surgeon Jonathan Sunkin, MD is also trained in the ROSA technology and offers the procedure at Falmouth Hospital.
Just shy of 800,000 total knee replacements are done every year in the United States, according to the American College of Rheumatology. Total knee replacement, also known as total knee arthroplasty, is a surgical procedure to replace surfaces of the knee joint with metal and plastic implants in patients with end-stage joint disease who have a decline in function of their knee, malalignment and often disabling pain.
The Advantages of Robotic Surgery
Total knee replacement surgery is complex and involves taking many measurements of the femur (thigh bone), tibia (shin bone), and angles of the two bones to ensure good placement of the new joint parts. Surgeons also check the rotation of the femur and alignment of the leg, according to Dr. Dimond.
“During traditional knee replacement surgery, two of the instruments I used were a intramedullary guide, which was a rod inserted into the femur that gave me an assessment of the patient’s hip center and alignment of the limb,” he said. “The second instrument was the extramedullary guide, placed outside the tibia. It clasps around the ankle, runs up outside of the tibia and guides the standard tibia cut. These instrument guides would show alignment of the leg so I would know where to cut the bones for placement of the new knee joint.”
With the ROSA robot, there is no need for a CT scan prior to surgery for the planning stage.
“Once I place the tracker pins on the femur and the tibia and get the measurements of the anatomy intraoperatively, an image of the implant with measurements will show up on a screen,” Dr. Dimond said. “I can move the image of the knee in different planes on the screen, so I know in real time that I have all the information I need to know before we start the surgery.”
"ROSA will then give me a complete game plan perfectly tailored to the patient’s leg anatomy with all the measurements I have done.”
The computer screen shows the progress of the measurements he took before he begins surgery and during surgery, including movement measurements for flexion and extension of the leg, and it also validates every measurement taken.
The robotic arm then comes into play with a cutting guide to show the surgeon exactly where to make the cuts in the bone and it shows where to remove more or less tibia and femur bone to get the proper alignment.
“Once the new joint replacement parts are in position, ROSA helps me to assess the ligaments to make sure they are balanced in tension on both sides of the new knee, which is very important in the longevity of the replacement parts, to prevent wear on the new components,” he said.
The Road to Recovery with PersonaIQ
Along with the ROSA robotic system, Dr. Dimond and Dr. Sunkin have begun using another new technology to track the progress of their knee replacement patients. Called the Persona IQ (PIQ), it is a personalized knee replacement device that records information about the patient’s new knee, according to Dr. Dimond.
“The implant measures step speed, range of motion, cadence and how the patient’s recovery is going in their early postoperative period,” he said. Patients can download a mymobility app to their cell phone and upload their physical therapy exercises. Patients can also use the app preoperatively and it will remind them of tasks they need to complete before surgery including exercises, a preop class, when to stop taking their anti-inflammatory medications, as well as providing communication between their surgeon and care team. (Please see a separate story on Persona IQ in this week’s Cape Cod Health News.)
The Future of ROSA
“The next version of ROSA is anticipated to be in November 2025 and will include a feature that remembers every one of the measurements and cuts on every patient,” Dr. Dimond said. “I will be able to go back a year later, for example, and review the preoperative plan and correlate how the patient recovered, and we will be able to track the patient’s recovery. It is all very exciting!”
