Periarticular Injection for Pain Control After Surgical Treatment of Knee Periprosthetic Joint Infection

Periprosthetic joint infection (PJI) is a serious complication after total knee arthroplasty, and treatment often requires extensive surgery. Intraoperative periarticular injection (PAI) of local anesthetic is commonly used during primary total knee arthroplasty to improve postoperative pain control, but it is not typically used for infection-related procedures due to fears of spreading infection. This study evaluated the safety and efficacy of the use of PAI in the treatment of knee PJI.

We performed a retrospective review of 309 patients who underwent surgical treatment of knee PJI between 2015 and 2023. Intraoperative PAI was administered to 121 patients, whereas 188 did not receive PAI and served as controls. Postoperative pain scores and opioid consumption (morphine milligram equivalents [MMEs]) were recorded at 24, 48, and 72 hours, and reinfection rates were assessed at one year postsurgery.

There were no significant differences in reinfection rates at 12 months (5.0% with PAI versus 8.0% without, P = 0.30). The PAI group reported decreased pain scores compared to the non-PAI group at the 24-hour (5.53 versus 5.71, P < 0.001) and 48-hour marks (5.35 versus 5.64, P = 0.042). Patients who received PAI also required significantly less average MMEs in the first 24 hours after surgery compared to the non-PAI group (90.2 versus 130.4 MME, P = 0.0036).

Intraoperative PAI during surgical treatment for knee PJI reduced early postoperative opioid requirements and patient-reported pain levels without increasing the risk of reinfection. These findings support the safe use of PAI as an adjunct to optimize postoperative pain control and reduce opioid exposure in this high-risk population.