Genicular artery embolization for knee osteoarthritis: Results of the LipioJoint-1 trial

Transarterial Embolization for Musculoskeletal Pain Management: AJR Expert Panel Narrative Review

Musculoskeletal embolization has emerged in recent years as a treatment for chronic joint pain, as the inflammatory cascade responsible for such pain has become better understood. Studies have demonstrated a complex interplay between joint inflammation and synovial hypervascularity that causes growth of new unmyelinated nerve fibers responsible for pain. Embolization targets joint hypervascularity, to disrupt the inflammatory cycle and provide pain relief. The standard treatment algorithm for chronic joint pain is well-established and entails escalating therapeutic options that include exercise, self-management programs, analgesic medications, intra-articular injections, and finally surgical replacement or release. Genicular artery embolization (GAE), targeting abnormal vasculature around the knee joint, is the most heavily studied musucloskeletal embolization procedure, reflecting the high worldwide prevalence and increasing incidence of knee osteoarthritis. GAE is now supported by multiple prospective studies, including randomized control trials comparing GAE versus sham treatment. Embolization has also extended outside of the knee joint to include the shoulder (treatment of adhesive capsulitis or secondary stiff shoulder), elbow (medial/lateral epicondylitis), hip (osteoarthritis, great trochanteric pain syndrome), and ankle (plantar fasciitis). This AJR Expert Panel Narrative Review discusses the current status of transarterial embolization for musculoskeletal pain management, focusing on treatment of knee osteoarthritis and chronic shoulder pain.

Imaging in France: 2024 Update

Radiology in France has made major advances in recent years through innovations in research and clinical practice. French institutions have developed innovative imaging techniques and artificial intelligence applications in the field of diagnostic imaging and interventional radiology. These include, but are not limited to, a more precise diagnosis of cancer and other diseases, research in dual-energy and photon-counting computed tomography, new applications of artificial intelligence, and advanced treatments in the field of interventional radiology. This article aims to explore the major research initiatives and technological advances that are shaping the landscape of radiology in France. By highlighting key contributions in diagnostic imaging, artificial intelligence, and interventional radiology, we provide a comprehensive overview of how these innovations are improving patient outcomes, enhancing diagnostic accuracy, and expanding the possibilities for minimally invasive therapies. As the field continues to evolve, France's position at the forefront of radiological research ensures that these innovations will play a central role in addressing current healthcare challenges and improving patient care on a global scale.

Genicular Artery Embolization for Treatment of Symptomatic Knee Osteoarthritis-2-Year Outcomes from a Prospective IDE Trial

PURPOSE

To report the 24-month outcomes and subgroup analysis evaluating the safety and effectiveness of the genicular artery embolization (GAE) for the treatment of symptomatic knee osteoarthritis (OA).

MATERIALS AND METHODS

Forty participants with symptomatic moderate-to-severe knee OA from a single-center, single-arm, prospective investigational device exemption trial of GAE were included in this study. Abnormal genicular artery neovascularity was identified at the subject's focal knee pain with digital subtraction angiography and cone-beam computed tomography (CT). Embolization was performed with 100-μm microspheres. The primary end point was treatment effectiveness as measured by sustained improvement in OA symptoms at 24 months, quantified using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Treatment success was defined as ≥50% decrease in WOMAC relative to baseline. Clinical outcomes were assessed with mean age of 66.0 years (SD ± 8.1) and body mass index of 30.1 kg/m2 (SD ± 6.2).

RESULTS

Of the 40 patients, 2 (5.0%) were lost to follow-up. Overall, 18 of 38 (47.4%) patients demonstrated ≥50% reduction in WOMAC at 24 months. In the subset of patients with initial clinical success at 12 months, 18 of 25 (72.0%) reported sustained clinical success at 24 months. Seven of 25 (28.0%) patients had symptom recurrence between 12 and 24 months and were determined to be clinical failures. All treatment-related adverse events occurred within 12 months after GAE, without additional events after 12 months.

CONCLUSIONS

GAE is effective in achieving sustained symptom relief related to moderate-to-severe knee OA for up to 24 months with an acceptable safety profile.

Minimally Invasive Therapies for Knee Osteoarthritis

Knee osteoarthritis (KOA) is a musculoskeletal disorder characterized by articular cartilage degeneration and chronic inflammation, affecting one in five people over 40 years old. The purpose of this study was to provide an overview of traditional and novel minimally invasive treatment options and role of artificial intelligence (AI) to streamline the diagnostic process of KOA. This literature review provides insights into the mechanisms of action, efficacy, complications, technical approaches, and recommendations to intra-articular injections (corticosteroids, hyaluronic acid, and plate rich plasma), genicular artery embolization (GAE), and genicular nerve ablation (GNA). Overall, there is mixed evidence to support the efficacy of the intra-articular injections that were covered in this study with varying degrees of supported recommendations through formal medical societies. While GAE and GNA are more novel therapeutic options, preliminary evidence supports their efficacy as a potential minimally invasive therapy for patients with moderate to severe KOA. Furthermore, there is evidentiary support for the use of AI to assist clinicians in the diagnosis and potential selection of treatment options for patients with KOA. In conclusion, there are many exciting advancements within the diagnostic and treatment space of KOA.

Lipiodol Versus Imipenem/Cilastatin in Genicular Artery Embolization: A Retrospective Study on Safety and Clinical Success

PURPOSE

This study aims to evaluate the safety and effectiveness of genicular artery embolization (GAE) using lipiodol in comparison to imipenem/cilastatin (IPM-CS).

MATERIALS AND METHODS

This retrospective study screened patients who underwent GAE between January 2022 and February 2023 for inclusion. Clinical outcomes were assessed at 1, 3, and 6 months post-procedure using the Visual Analog Scale (VAS) for pain and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) for pain, stiffness, functional capacity, and total scores. Technical and clinical success rates, complications, and patient-reported outcomes were assessed.

RESULTS

A total of 42 patients were included in the study, with 13 patients treated with lipiodol and 29 with IPM-CS for GAE. Transient skin discoloration was noted in 23.1% of lipiodol patients and 31% of the IPM-CS group (p = 0.722). One patient (7.6%) in the lipiodol group developed knee edema and erythema due to drug-induced vasculitis (p = 0.309). Clinical success rates in the lipiodol group were 76.9% at 1 month, consistent at 3 months, and 69.2% at 6 months. For the IPM-CS group, success rates were 89.7, 86.2, and 75.9%, respectively, with no significant differences (p = 0.353, p = 0.657, p = 0.713). The median percentage change in WOMAC stiffness scores for the lipiodol group at 1, 3, and 6 months post-GAE were - 25%, - 16.7%, and - 16.7%, respectively, while the IPM-CS group showed decreases of - 40%, - 50%, and - 50%. Significant differences were found between the groups at all time points (p = 0.017, p = 0.009, and p = 0.002, respectively).

CONCLUSION

Lipiodol shows comparable clinical success to IPM-CS in GAE.

Society of Interventional Radiology Research Reporting Standards for Genicular Artery Embolization

Genicular artery embolization (GAE) is an emerging, minimally invasive therapy to address the global burden of knee osteoarthritis (OA) and the unmet needs for medically refractory disease. Although total knee arthroplasty has been a standard intervention for severe cases, GAE is developing into a promising alternative, particularly for patients ineligible for or unwilling to undergo surgery. GAE targets the inflammatory cascade underlying OA pathophysiology by arresting neoangiogenesis and preventing pathological neoinnervation, offering potential pain relief. Although early studies have established safety and short-term effectiveness, ensuing studies are needed to validate long-term safety, durability, and comparative effectiveness and to optimize patient selection, embolic agent selection, and administration techniques. Standardized reporting guidelines are therefore essential to enhance transparency and reproducibility across clinical trials, facilitating data aggregation and comparison. This Society of Interventional Radiology (SIR)-endorsed reporting standards consensus document provides a framework to harmonize future research efforts and to improve the interpretation of outcomes.

Transarterial Embolization of Geniculate Arteries Reduces Pain and Improves Physical Function in Knee Osteoarthritis-A Prospective Cohort Study

Knee osteoarthritis (OA) affects millions worldwide, leading to pain and reduced quality of life. Conventional treatments often fail to provide adequate relief, necessitating new therapeutic approaches. This study evaluated the efficacy and safety of genicular artery embolization (GAE) using permanent microspheres in patients with mild-to-moderate knee OA. In this prospective, single-center study, 17 participants underwent GAE. KOOS (Knee injury and Osteoarthritis Outcome Score), WOMAC (The Western Ontario and McMaster Universities Arthritis Index), and IPAQ (International Physical Activity Questionnaire) scores, along with physical performance tests, medication use, and dual-energy X-ray absorptiometry (DEXA) scans, were assessed at baseline and at multiple follow-up points over six months. The primary endpoint, VAS at six months, showed significant improvement (median reduction from 66 mm to 40 mm, p = 0.0004). All pain and function scores, as well as physical performance tests, improved significantly. No clinically relevant changes in medication use or DEXA parameters were observed after six months. Only minor, self-limiting adverse events occurred. This study indicates that GAE is a promising minimally invasive treatment for knee OA, providing significant pain relief and functional improvement. However, further long-term, randomized trials are needed to confirm these findings and establish optimal patient selection criteria.

Genicular Artery Embolization: A New Tool for the Management of Refractory Osteoarthritis-Related Knee Pain

Osteoarthritis (OA) of the knee is a prevalent cause of chronic pain and disability, particularly affecting women. While traditionally attributed to chronic wear and tear, recent evidence highlights multifactorial pathogenesis involving low-grade inflammation and neoangiogenesis. Current therapeutic options include physical therapy, pharmacotherapy, and total knee arthroplasty (TKA). However, a subset of patients remain symptomatic despite conservative measures, necessitating the development of minimally invasive interventions. Genicular artery embolization (GAE) emerges as a promising option, targeting neovascularization and inflammatory processes in OA. This paper reviews the pathophysiological basis, patient selection criteria, procedural details, and outcomes of GAE. Notably, GAE demonstrates efficacy in relieving knee pain and improving function in patients refractory to conventional therapy. While further research is warranted to elucidate its long-term outcomes and compare it with existing modalities, GAE represents a novel approach in the management of symptomatic knee OA, potentially delaying or obviating the need for surgical intervention. Here, we synthesize the relevant literature, technical details of the procedure, and future perspectives. Moreover, the success of GAE prompts the exploration of transarterial embolization in other musculoskeletal conditions, underscoring the evolving role of interventional radiology in personalized pain management strategies.

Genicular Artery Embolization: Embolic Material and Imaging Review

Osteoarthritis (OA) of the knee is a degenerative condition impacting numerous individuals globally. Genicular artery embolization (GAE) has emerged as an effective minimally invasive therapy for managing medically refractory OA-related pain in patients who are not eligible for surgery. This intervention works by disrupting the inflammatory and neoangiogenic pathways that contribute to pain. The efficacy of GAE has been demonstrated in various clinical trials, yielding promising results. This review aims to explore recent advancements in the embolic materials used during GAE, examining their properties and potential benefits. Additionally, it will describe the use of pre-, intra-, and postprocedural imaging-particularly magnetic resonance imaging and other modalities-to optimize GAE outcomes.