More than 1 million patients undergo hip and knee replacements annually in the United States, making joint replacement one of the most common surgical procedures.

Ongoing advancements in the field, including robotics, have made these surgeries safer and more effective.

“Robotic technology allows us to be better surgeons,” said Hue Luu, MD, an orthopaedic surgeon at the University of Chicago Medicine, where he and other orthopaedic experts offer the latest tools and approaches to help patients live longer and more active lives.

UChicago Medicine was the first medical center in Chicago — and one of the first academic centers in the region — to adopt robotic-assisted knee and hip replacement surgeries. Today, it performs thousands of procedures every year.

Robotics make joint replacement safer, quicker

Used during surgery and as party of pre-surgery planning, robotic tools allow surgeons to be highly accurate, leading to fewer errors and better outcomes.

“Robotics help us be more precise when positioning the implants, which is very important in orthopaedics,” Luu said. “Because if something is off by as little as three degrees in a knee replacement, for example, those patients are at higher risk for failure of the device in the long-term.”

With hip replacements, it’s imperative that a patient’s leg length isn’t changed incorrectly. Without the precision of robotics, patients are at higher risk for problems like dislocation, wear, or bursitis (inflammation caused by friction in the hip area) that can prompt additional surgeries. 

“We’re working in millimeter increments, so we have to compare to our plans and make decisions during surgery,” Luu said.

Robotic technology is also less invasive, which can reduce recovery times and minimize swelling and pain. Although recovery times can vary, patients are typically up and moving quickly, and they can often begin physical therapy immediately upon returning home.

“A lot of patients now go home the same day after surgery. We encourage them to walk the same day,” said Aravind Athiviraham, MD, an orthopaedic surgeon at UChicago Medicine. “Overall, recovery is a lot quicker than it was in the past. Initial recovery is typically about three months before patients can comfortably do most of the activities they were doing before surgery.”

Cementless knee replacement may have long-term benefits

In a traditional total knee replacement, implants are attached to the bone using a type of cement, which typically allows the joint replacement to last 10 to 20 years.

Today, “cementless” procedures can be a good option for patients who have strong, healthy bones. This newer technology enables ingrowth of bone onto the implant, which may extend the longevity of the device.

Athiviraham is focused on sports medicine and treats a lot of younger, active patients facing pain or injury who want to maintain an active lifestyle for many more decades. These patients are often strong candidates for the cementless procedure, as they have good bone quality.

“The nice thing about cementless total knee replacements is that the replacements get stronger over time, as opposed to being concerned about the durability and strength of the cement-metal interface over time,” Athiviraham said.

Better materials and robotic-assistance are driving success

Thirty years ago, hip replacements typically lasted 10 to 15 years for most patients. Today, surgeons anticipate devices may last 25 to 30 years — and possibly longer.

“The materials are much better now, and using robotics helps us put the components in the best positions possible, which then sets patients up for the best possible scenario,” said Luu. 

UChicago Medicine physicians are committed to treating the whole patient, which means preparing carefully ahead of surgery, ensuring that all of the options for more conservative care have already been explored, and consulting with the patient’s primary care doctor to make sure everyone on their care team is on the same page.

A patient may be referred out to physical therapy ahead of surgery to strengthen the muscles around the joint to make rehabilitation easier.

Overall knee replacements are a highly successful procedure, and Athiviraham estimates that about 95% of his joint replacement patients are satisfied with their surgery results. However, as with any surgery, a small group of patients, usually under 5% may continue to experience pain despite normal radiographs and no sign of infection. A multicenter National Institute of Health (NIH) funded trial, of which University of Chicago is a participant, is currently under way to further elucidate potential risk factors for this.

“In the end, our patients have to be comfortable with the decision: Is this the right time for me, or do I want to wait?” Luu said. “I leave that up to them. Often, they’ve already made that decision by the time they see me, which makes those discussions easier.”