By Lauren Wanko
Meet Roy, the newest addition to the OR at Robert Wood Johnson University Hospital in Hamilton. It’s a Robotic Arm Assistance used in total hip and partial knee replacement surgeries.
“Technology is a wonderful tool and the robot is really a tool to the surgeon. This allows us to be more accurate, more reproducible,” said Dr. John Schnell.
The patient will first get a CT scan which is uploaded onto the computer. The surgeon then receives a pre-operative plan, which indicates where the implants will best fit the patient. The surgeon reviews the plan and can make any changes if need be.
The image of hip or knee appears on the screen during the surgery. Colored areas indicate what portions of the bone need to be removed for the implant. Once the knee is exposed, the surgeon controls a robotic arm. There’s a burr or drill at the end of the arm that cuts the bone.
“What the burr does, it takes that plan and cuts away bone so the implant can fit on a patient so for example here the on the tibia you can see this is where the computer thinks the implant should go,” said Dr. Arjun Saxena.
If the arm is moved too far to the left or right, or goes too deep, the drill will shut down.
“The computer allows us to make the bone cuts up to sub millimeter accuracy,” Saxena said.
The color on the screen will change in real time as the surgeon cuts away the bone.
“In surgery we never get this full 360 view so this just gives us more info to allow us to give patient the best possible outcome,” said Saxena.
Stryker Orthopaedics, which manufacturers Roy, says there are more than 200 similar systems in hospitals and surgery centers throughout the country. The technology’s been used in more than 50,000 surgeries since 2006. Robert Wood Johnson Hamilton just unveiled it on Friday. Doctors say there’s no increased cost to the patient.
“This is certainly a cost that’s incurred to the hospital. The hope is if you are more accurate, more reproducible, in your joint replacement then you have less complications and overall to the hospital less cost,” Schnell said.
Stryker Orthopaedics says they’re still waiting on final FDA clearances to use the system for total knee replacements. Meantime for those surgeries, Dr. Michael Duch has been using patient specific instrumentation. A CT scan and a computer system are used to create the custom models or block formats.
“That fits over an individual’s bones on the femur and tibia side to make the proper cuts for proper alignment and proper sizing of the prosthesis,” he said.
Dr. Duch has used the custom models in more than 350 surgeries. As for Roy, he’ll start work in the OR by later this month.