Cryoneurolysis for Patients Undergoing Total Knee Arthroplasty

Key Messages

What Is the Issue?

• Knee replacement surgery (knee arthroplasty) is a common surgery in Canada primarily used to treat knee osteoarthritis, which causes pain, swelling, and reduced mobility. Although total knee arthroplasty (TKA) is effective, many people who undergo the procedure experience substantial postoperative pain. Effective pain control is important for helping patients move and leave the hospital sooner, improving patient outcomes. Current best practices emphasize multimodal pain management strategies while limiting opioid use.
• Cryoneurolysis uses extreme cold (approximately −70°C) to temporarily damage and disrupt targeted nerve function to reduce pain for weeks or months and is of interest for pain management after TKA. However, its clinical effectiveness and cost-effectiveness compared to those of other pain management strategies for TKA are uncertain. This Rapid Review was requested by policy decision-makers.

What Did We Do?

• To inform decisions regarding the use of cryoneurolysis for pain management after TKA, we conducted a rapid review to summarize evidence comparing the clinical effectiveness and cost-effectiveness of cryoneurolysis to those of other pain management interventions not involving cryoneurolysis for people undergoing TKA.
• We searched key resources, including journal citation databases, and conducted a focused internet search for relevant evidence published since 2020.

What Did We Find?

• We identified 3 systematic reviews and 1 companion report to a cohort study. No cost-effectiveness studies were identified.
• All studies were conducted in the US and mostly included older adults (mean age 65 years or older) undergoing primary unilateral TKA. Study sizes ranged from 16 to 356 participants with follow-up ranging from 3 weeks to 12 months. Two cryoneurolysis devices were compared with sham cryoneurolysis or standard care, but the specific nerves targeted, timing, treatment protocols, and standard of care varied across studies.
• Overall, studies suggest that cryoneurolysis may modestly reduce early postoperative pain (up to 2 weeks post-TKA), opioid use, and hospital length of stay. However, not all statistically significant differences were large enough to be considered clinically meaningful, and results were inconsistent at most time points. There were no consistent associations observed between cryoneurolysis and physical function or sleep disturbance. Serious adverse events were rare, and larger studies are needed to better understand the risks. The evidence base has limitations, including risk of bias, inconsistent outcomes and results, and uncertain relevance to the context in Canada.

What Does This Mean?

• Cryoneurolysis may be associated with modest benefits in early postoperative pain, opioid use, and hospital stay without clear increases in serious adverse events compared to control interventions in the included studies. Limitations in the evidence reduce confidence in these findings, and additional research is needed.
• Decision-makers could consider differences in participant populations, surgical procedures, standards of care, and potential equity and implementation issues when deciding how applicable this evidence is to their context.