Cryoneurolysis for non-cancer knee pain: A scoping review.

Background and objective: Cryoneurolysis involves percutaneous insertion of a cryoprobe induced to extremely cold temperatures to disrupt peripheral nerve conduction. The primary objective of this scoping review is to summarize and critically appraise the current evidence for the benefits and safety of cryoneurolysis for non-cancer knee pain. The secondary objective is to describe the variations in cryoneurolysis techniques used. Methods: MEDLINE, EMBASE, PubMed, Cochrane Library, and Web of Science were searched from their inception to February 2023 for any primary literature investigating the use of cryoneurolysis for non-cancer-related knee pain. Data was extracted for study characteristics, intervention characteristics, and clinical outcomes. Results: Fourteen studies were identified, including three randomized controlled trials, four retrospective cohort studies, and seven case studies/series. Two studies included knee osteoarthritis patients, three studies included non-specific chronic knee pain patients; and nine studies included pre- or post-total knee arthroplasty patients. Ten studies targeted the infrapatellar branch of the saphenous nerve while the remaining four studies did not report the nerve targeted. Studies consistently demonstrated improvements in pain, function, quality of life, and opioid consumption. Most adverse events were mild and self-limiting. Considerable variations in technique parameters were observed. Conclusions: Cryoneurolysis is a promising intervention to improve outcomes in non-cancer knee pain populations, particularly in mild-to-moderate knee osteoarthritis and pre-total knee arthroplasty populations. However, cryoneurolysis for knee pain remains largely investigational as more high-quality randomized controlled trials are required to further elucidate efficacy as well as optimal nerve selection and technique.