Cryoneurolysis before Total Knee Arthroplasty in Patients With Severe Osteoarthritis for Reduction of Postoperative Pain and Opioid Use in a Single-Center Randomized Controlled Trial

Background: We hypothesized that preoperative cryoneurolysis of the superficial genicular nerves in patients with osteoarthritis would decrease postoperative opioid use relative to standard of care (SOC) treatment in patients undergoing total knee arthroplasty (TKA). Methods: Patients received either cryoneurolysis (intent-to-treat [ITT]: n = 62) or SOC (ITT: n = 62). The cryoneurolysis group received cryoneurolysis of the superficial genicular nerves 3-7 days before surgery plus a similar preoperative, intraoperative, and postoperative pain management protocol as the SOC group. The primary end point was cumulative opioid consumption in total daily morphine equivalents from discharge to the 6-week study follow-up assessment. Secondary end points included changes in pain and functional scores. Primary and secondary end points were assessed using ITT and per-protocol (PP) analyses. Results: The primary end point was not met in the ITT analysis (4.8 [cryoneurolysis] vs 6.1 [SOC] mg; P = .0841) but was met in the PP analysis (4.2 vs 5.9 mg; P = .0186) after excluding patients with medication deviations or missing follow-up data. Compared with the SOC group, the cryoneurolysis group had improved functional scores and numerical improvements in pain scores across all follow-up assessments, with significant improvements observed in current pain from baseline to the 72-hour and 2-week follow-up assessments and pain in the past week from baseline to the 12-week follow-up assessment. Conclusion: Findings from the PP analysis suggest that preoperative cryoneurolysis in patients with knee osteoarthritis can reduce opioid consumption and improve functional outcomes after TKA. (C) 2020 The Authors. Published by Elsevier Inc.