Westerheide. The custom approach has already garnered positive feed-
back from Dr. Westerheide's patients, and that's what's driving the
change. "If 5% of patients who get knee replacement aren't happy, that's
a very reasonable goal," he says. "We should be able to achieve that."
3. Better alignment
The goal for all the new knee-related technology is to achieve more
precise outcomes, says David Mayman, MD, a hip and knee surgeon at
Hospital for Special Surgery in New York City. "We know the tradition-
al tools we've used over the last 50 years are not all that accurate," he
says. "We've done OK with that technology. But it's 2019. We can do
better."
One solution: Handheld accelerometer- and gyroscope-based instru-
ments that can provide surgeons with alignment guidance, says Dr.
Mayman. The single-use device has inertial sensors that give surgeons
real-time feedback about where to cut into the femur and tibia to proper-
ly place the implant. Surgeons use the palm-sized device to get an exact
reading of the proper angles (flexion, varus/valgus alignment and slope)
in relation to the mechanical axis of the leg. Once they get the desired
readings, surgeons pin their blocks and make their cuts.
At less than $1,000 per instrument, the device doesn't come with the
hefty capital investment that the other options do, says Dr. Mayman.
They also work with any implant, which gives you flexibility.
"If you don't do as many and don't have that level of confidence, this
gives you that level of confidence," says Dr. Mayman. "I set the device
up. These are my numbers. I know they are going to be accurate."
A P R I L 2 0 1 9 • O U T PA T I E N T S U R G E R Y. N E T • 1 5
outpatient total joints," says Ms. Dow. "Patients feel good when
they know what's coming. There are no big surprises, and they
appreciate that." — Matthew Nojiri
