Genicular artery embolization for the treatment of knee osteoarthritis: A baseline report of a living evidence synthesis

Background: Genicular artery embolization has been recently adopted for the management of secondary pain to inflammatory diseases of the locomotor apparatus and studies assessing its use in the treatment of knee osteoarthritis have been increasing their publication rate in the recent years, hence, it constitutes a suitable target for a living evidence synthesis.Objective: This living evidence synthesis aims to provide a timely, rigorous, and continuously updated summary of the evidence available on the role of genicular artery embolization for the treatment of patients with chronic pain secondary to knee osteoarthritis.Methods.Design: This constitutes the baseline synthesis report of a Living Evidence Synthesis. Based on its conclusions we have activated the evidence monitoring to identify emerging studies that inform on evaluating the effect of genicular artery embolization versus conservative management or drug therapy (no application of genicular artery embolization) in patients with chronic pain secondary to knee osteoarthritis refractory to standard-of-care that have been left unresolved by current evidence and require a living evidence approach.Evidence identification, screening, and selection : The literature search was designed and developed following the Epistemonikos procedures. Results from the search were automatically included in the Epistemonikos “Living Overview of Evidence (L·OVE)” platform. Two reviewers screened all titles and abstracts with the support of automated classifiers that excluded references with a low probability of being relevant. In this baseline report, we included randomized studies and moderate-to-high quality systematic reviews of randomized studies that evaluated the use of genicular artery embolization compared to conservative management or drug therapy (no application of genicular artery embolization) in patients with chronic pain secondary to knee osteoarthritis refractory to standard-of-care treatments. We extracted data and assessed the risk of bias using appropriate instruments. Considered critical or important outcome measures for decision making included knee pain, overall functional improvement, changes in the need for pain medication, health-related quality of life, complications and adverse events. We applied the GRADE approach to assess the certainty of the evidence found for each outcome. We will continuously monitor the evidence by performing daily searches and monthly screening of the retrieved references. Additionally, we will manually search for ongoing studies in the International Clinical Trials Registry Platform trial registries every three months. The evidence monitoring, including decisions to incorporate evidence and to withdraw the question from the living mode will follow the process proposed in our protocol (OSF osf.io/9yjkz).A living, web-based version of this review will be openly available next year. We will resubmit it for publication every time the conclusions change or whenever there are substantial updates.Results: The searches retrieved nine systematic reviews and, subsequently, nine randomized controlled trials to the L·OVE platform. We considered all systematic reviews and seven randomized controlled trials as potentially eligible and reviewed all of them in full text. No moderate-to-high quality systematic reviews that could be included according to the pre-established selection criteria were found. Finally, we located and included two randomized controlled trials that evaluated the use of genicular artery embolization compared to the use of only conservative management or drug therapy in patients with chronic pain secondary to knee osteoarthritis refractory to standard-of-care. The estimates for pain showed inconsistent results, and low to moderate certainty evidence suggest no differences on the effects observed for overall function, health-related quality of life, and changes in the need for pain medication with the use of genicular artery embolization. No serious complications or major adverse events were observed. The GRADE quality of evidence for the main outcomes was moderate to low.Conclusions: Overall, evidence of moderate to low certainty suggests that there is insufficient data to conclude whether or not the genicular artery embolization results in beneficial effects when used for the treatment of knee osteoarthritis, in terms of knee pain, overall function, health-related quality of life, reduction in the need for pain medication, adverse event or complications, compared with the standard-of-care treatment. Larger randomized controlled trials are needed to determine the effects of the use of genicular artery embolization for chronic pain secondary to knee osteoarthritis refractory to standard-of-care treatment.