St. John’s Riverside Hospital: Increasing Joint Replacement Precision With MAKOplasty

By Thomas Crocker
Monday, April 29, 2019

David Lent, MD, FAAOS, Chief of Orthopedic Surgery at St. John’s Riverside Hospital, explains how he and his colleagues at Westchester Orthopedic Center increase the quality and reduce complications of knee and hip replacement through MAKOplasty, a surgery that uses the robotic arm-assisted technology Mako.

David Lent, MD, FAAOS

Q: What does MAKOplasty entail?

Dr. Lent: First, I make a 3D model of the extremity to be operated on, which allows me to operate on the joint virtually before the surgery itself to ensure the components are appropriately sized and ideally positioned. With conventional instruments, surgeons can only estimate where the components should go. To implement the preoperative plan, instead of using a primitive saw or other instruments to cut the bone, I use the Mako robotic arm, which operates under my guidance. The robotic arm cuts the bone exactly as planned, to the micromillimeter. Mako essentially eliminates the possibility for error because it won’t let the surgeon deviate from the preoperative plan.

Q: Who is a candidate for MAKOplasty?

Dr. Lent: All patients who plan to undergo joint replacement should have a MAKOplasty procedure.

Q: What are the key benefits?

Dr. Lent: To perform a conventional hip or knee replacement, I need to see everything, which necessitates an open approach with a large incision. With MAKOplasty, the robot knows the anatomy without having to dissect as much, so the incision is smaller. That means less blood loss, reduced pain and minimal scarring. Patients enjoy faster rehabilitation and an earlier return to activities.

One of the main problems patients can have with conventional hip replacement is the joint popping out of place. By allowing the surgeon to optimize the size and positioning of the components, the robot diminishes that complication considerably.

The knee is a complex joint that must be replaced with utmost precision. If the alignment of the components is off, patients have significant pain and don’t regain full range of motion. The robot ensures the implants are put in the ideal position 100 percent of the time.

Q: How does Mako facilitate partial knee replacement?

Dr. Lent: Many people have arthritis in only one compartment of the knee. In the old days, we replaced the entire joint. With Mako, we can identify the damaged portion, leave viable cartilage and bone in place, and replace the deteriorated part. That allows patients to keep a lot of their natural cartilage and ligaments, and the length of the incision and amount of dissection are a fraction of what they would be for total knee replacement.

Q: What distinguishes Westchester Orthopedic Center as a destination for MAKOplasty?

Dr. Lent: St. John’s Riverside Hospital was the first in the region to acquire Mako, more than six years ago. I have performed approximately 800 MAKOplasty procedures; collectively, the team of surgeons at Westchester Orthopedic Center has performed more than 1,000. Surgeons from around the world visit our center to observe MAKOplasty, and I travel the country instructing other teams that are establishing programs. MAKOplasty is beginning to be recognized as the premier way of performing joint replacement surgery.

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