HSS: Navigation, Robotics Don’t Increase PJI After THA

Given that using computer navigation or robotic assistance during primary total hip arthroplasty (THA) adds operative time and requires more surgical equipment and personnel, what is its impact on periprosthetic joint infection (PJI) after primary THA?

That is the question a team from Hospital for Special Surgery (HSS) in New York asked, leading to their study: “Robotics and Navigation Do Not Affect the Risk of Periprosthetic Joint Infection Following Primary Total Hip Arthroplasty: A Propensity Score-Matched Cohort Analysis,” appears in the April 3, 2024 edition of The Journal of Bone and Joint Surgery.

Co-author Alberto Carli, M.D. told OTW, “We conducted this study in response to the increasing popularity of utilizing robotic assistance for total hip and total knee replacement procedures. Although robotic assistance has been heralded as helping orthopedic surgeons achieve much more precise implant position when performing hip and knee replacement surgeries, the procedure itself takes more time and a large robotic tower with an attached arm must enter the sterile field.”

“The arm itself actually enters the surgical wound at times as well,” added Dr. Carli. “This then led to the question of whether utilizing robotic assistance leads to increased risk of periprosthetic joint infection (PJI), a rare but devastating complication that can occur after replacement surgery. We therefore undertook this carefully designed retrospective analysis to answer this question.”

The team looked at 12,726 patients who had undergone primary THA at their institution between 2018 and 2021, stratifying patients by technique (conventional THA, computer-navigated THA, or robotic-assisted THA and matching them 1:1.

In the THA versus robotic-assisted THA analysis there were 4,006 patients (2,003 in each group). In the THA versus computer-navigated THA group there were 5,288 patients (2,644 in each group).

Computer-navigated-THA and robotic-assisted-THA were associated with longer operative times compared with conventional THA by 3 and 11 minutes, respectively. The rates of PJI after conventional THA (0.2% to 0.4%) were similar to those after computer-navigated THA (0.4%) and robotic-assisted-THA (0.4%).

“We found that, fortunately, use of robotic assistance was not associated with an increased risk of PJI in our matched patient cohorts,” stated Dr. Carli to OTW. “This is despite all finding that robotic procedures do take significantly longer than procedures with conventional instrumentation. We were not surprised our year-over-year institutional infection rates have barely changed over the last five to six years (despite the increasing use of robotics), but I will say that we were relieved!”

“Although our study involved thousands of patients, given the inherently low infection rates that we achieve after hip and knee replacement, we are still statistically underpowered to detect smaller differences in infection rates. That is perhaps the greatest limitation in our paper. This is despite our institution performing the highest volume of hip and knee replacements in North America. Our future efforts will likely involve repeating such an analysis in several years once we have a larger case volume in order to increase our statistical power.”