Most people know someone who’s had a knee replacement. Around 800,000 are performed annually in the US, and that number is increasing rapidly. In 2014, only around 1% of knee replacements were performed with the aid of a robot. Now, it’s nearly 50%. This number will likely continue to increase.
Believe it or not, the first robotic surgery actually took place all the way back in 1985 using the PUMA 560 robotic arm. In orthopaedic surgery, the ROBODOC arm was used to assist with a hip replacement in 1992. While these marked the beginning of the trend, robotic assisted surgery didn’t become widely adopted until the 2000s. The da Vinci system, released in 1999, has become a mainstay in general surgery for numerous procedures.
In orthopaedics, robotic systems like Stryker’s Mako, Zimmer’s ROSA, Smith and Nephew’s CORI and Depuy’s VELYS, have exploded in popularity over the last decade. They all work differently but share the common purpose of allowing optimal implant positioning. Total knee replacement has been plagued by significantly lower satisfaction rates compared to total hip replacement. While up to 95% of patients are satisfied with their total hips, only around 80% are ultimately “satisfied” with their total knees.
The root cause of this discrepancy is not totally clear but thought to be related to the complex biomechanics of the knee joint. The hip functions as a ball-and-socket joint with significant inherent stability. The knee has a more complex biomechanical configuration and functions as a medially based, rotating hinge joint. This has proven much harder to replicate, and patients often complain that it feels unnatural. The ultimate goal of robotic assisted total knee replacement is to allow surgeons to be more accurate and precise in attempting to reconstruct this complicated mechanism. The end goal remains to provide durable pain relief and function for patients.
Over the next decades, we will see large advancements in surgical robotics and the addition of augmented reality in the OR. Massive amounts of data are being collected that hopefully will allow researchers to pinpoint the keys for successful knee replacement surgery and greatly improve that satisfaction rate in the future.
