Percutaneous Management of Osteoarthritis in the Knee: Proceedings from the Society of Interventional Radiology Research Consensus Panel

Efficacy and Safety of Cryoablation Compared with Cooled Radiofrequency Ablation of Genicular Nerves in Advanced Osteoarthritis of the Knee: A Study Protocol of Single-Centric, Assessor-Blinded, Randomized, Parallel-Group, Non-inferiority Study

PURPOSE

In patients with symptomatic osteoarthritis knee (OAK), cryoneurolysis (CRYO) and cooled radiofrequency ablation (C-RFA) are reported to be effective and safe; however, they have not been compared directly. The objective of this study is to compare CRYO and C-RFA of the genicular nerve (GN) in terms of efficacy and safety profile in patients with Kellgren and Lawrence (KL) grade ≥ 3 OAK.

METHODS

This single-centric, assessor-blinded, randomized, parallel-group, non-inferiority study will include 80 patients with KL grade ≥ 3 OAK. The patients with ≥ 50% pain relief on diagnostic block of three GNs will be randomized to one of the two groups, i.e., CRYO (n = 40) or C-RFA (n = 40). The three target GNs for the interventions will include: superior medial, superior lateral, and inferior medial. The primary outcome will be efficacy of CRYO or C-RFA at 2, 12, and 24 weeks post-procedure based on the 11-point Numerical Pain Rating Scale. The secondary outcomes will be functional improvement based on 12-item Oxford Knee Score and safety of both the procedures. The study is registered in the Clinical Trials Registry-India.

CONCLUSION

CRYO and C-RFA provide pain relief and improve functional outcome by preventing transmission of pain signals, though by distinct mechanisms. While C-RFA is an established treatment modality, recent evidence supports CRYO in patients with OAK. This study intends to demonstrate non-inferiority of CRYO against C-RFA, thereby supporting the use of CRYO as an additional treatment modality in patients with KL grade ≥ 3 OAK.

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

PURPOSE

The purpose of this study was to evaluate the safety and efficacy of transient genicular artery embolization (GAE) using an ethiodized oil-based emulsion for the treatment of knee osteoarthritis (KOA).

MATERIALS AND METHODS

This prospective, single-arm, open-label, multicenter, first-in-human cohort trial was registered on ClinicalTrials.gov (NCT04733092). The main inclusion criterion was diagnosis of KOA according to a visual analogue scale (VAS) pain score ≥ 40 mm (score range: 0-100 mm), despite conservative treatment for at least three months. Treatment efficacy was assessed using changes in VAS pain score, Mean Western Ontario & McMaster Universities osteoarthritis (WOMAC) function score (normalized to 100; score ranging from 0 to100) and outcome measures in rheumatoid arthritis clinical trials (OMERACT)-Osteoarthritis Research Society (OARSI) set of responder criteria.

RESULTS

Twenty-two consecutive participants (13 women; mean age, 66 ± 9 [standard deviation (SD)]) were included and underwent GAE. Emulsion consisted in a mixture of ioversol and ethiodized oil (ratio 1:3, respectively) prepared extemporaneously. The rate of serious adverse events attributed to GAE within one month was 5% (1/22), corresponding to reversible worsening of renal function. Immediate technical success rate was 100%. Mean VAS pain score dropped from 74.4 ± 16.5 (SD) mm at baseline to 37.2 ± 26.7 (SD) mm at three months (P < 0.001). Mean WOMAC function score (normalized to 100: score ranging from 0 to 100) decreased from 57.3 ± 17.1 (SD) at baseline to 33.5 ± 25.9 (SD) at three months (P < 0.001). At three months, 16 out of 22 participants (73%) were considered responders according to the OMERACT-OARSI set of responder criteria, including high improvement in either pain or WOMAC function, or improvement in both pain and WOMAC function.

CONCLUSION

GAE using an ethiodized oil-based emulsion is safe and improves pain and function in participants with KOA for at least three months.

Common Design, Data Elements and Core Outcome Measures Reported on Clinical Trials of Genicular Artery Embolization for Knee Osteoarthritis: An Interactive Systematic Review

RATIONALE AND OBJECTIVES

Genicular artery embolization (GAE) is an emerging, potentially effective treatment option in patients with knee osteoarthritis (OA). This study aimed to describe the current state of common design data elements (CDDEs) and core outcome measures (COMs) in recent trials of GAE for knee OA.

MATERIALS AND METHODS

A comprehensive search of seven online databases were searched within the Nested Knowledge AutoLit living review platform, followed by categorization of primary and secondary outcomes. Studies were tagged with the relevant outcomes of interest in each article. Results were synthesized and examined for the CDDEs.

RESULTS

Pain is the most frequent reported outcome, present in 23 of the 24 studies (95.8%). However, there is considerable variability in the description of in the study designs, procedural techniques, embolic materials, time points, and MRI parameters. Greater consistency is observed in eligibility criteria, and adverse events reporting. Although findings thus far have been favorable, current data is still constrained by the heterogeneity of the study design, embolization area nomenclature, limited follow-up, and in many cases, the absence of control group.

CONCLUSION

To enhance the potential for future meta-analyses and robust, evidence-based evaluations of GAE as a treatment for knee OA, further research is required to address the identified shortcomings. By establishing more standardized protocols, the efficacy and safety of GAE can be more accurately assessed and understood.

Genicular Artery Embolization for Treatment of Knee Osteoarthritis: Interim Analysis of a Prospective Pilot Trial Including Effect on Serum Osteoarthritis-Associated Biomarkers

PURPOSE

To characterize the safety, efficacy, and potential role of genicular artery embolization (GAE) as a disease-modifying treatment for symptomatic knee osteoarthritis (OA).

MATERIALS AND METHODS

This is an interim analysis of a prospective, single-arm clinical trial of patients with symptomatic knee OA who failed conservative therapy for greater than 3 months. Sixteen patients who underwent GAE using 250-μm microspheres and had at least 1 month of follow-up were included. Six patients completed the 12-month follow-up, and 10 patients remain enrolled. Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) was evaluated at baseline and at 1, 3, and 12 months. Serum and plasma samples were collected for biomarker analysis. The primary end point was the percentage of patients who achieved the minimal clinically important difference (MCID) for WOMAC pain score at 12 months. Baseline and follow-up outcomes were analyzed using the Wilcoxon matched-pairs signed-rank test.

RESULTS

Technical success of the procedure was 100%, with no major adverse events. The MCID was achieved in 5 of the 6 (83%) patients at 12 months. The mean WOMAC pain score decreased from 8.6 ± 2.7 at baseline to 4.9 ± 2.7 (P = .001), 4.4 ± 2.8 (P < .001), and 4.7 ± 2.7 (P = .094) at 1, 3, and 12 months, respectively. There was a statistically significant decrease in nerve growth factor (NGF) levels at 12 months. The remaining 8 biomarkers showed no significant change at 12 months.

CONCLUSIONS

GAE is a safe and efficacious treatment for symptomatic knee OA. Decreased NGF levels after GAE may contribute to pain reduction and slowing of cartilage degeneration.

Musculoskeletal Embolotherapy

Painful articular musculoskeletal (MSK) conditions are common, debilitating and sometimes difficult to treat. Transcatheter embolisation may offer an alternative way to manage the pain associated with these conditions, but the field is still in its infancy. To date, the most commonly studied indication is knee osteoarthritis, but the technique has been trailed in multiple other tissue beds, including for adhesive capsulitis and tendinopathies. Whilst early results appear promising, the existing studies are mostly open-labelled and non-randomised; there is a need for high-quality evidence to robustly assess the procedures efficacy. In this review, we set out to evaluate the current evidence underlying the pathophysiology and mechanism of action of embolisation; discuss the technical aspects of the procedure including embolic selection, and appraise the published clinical outcomes and adverse effects. Finally, we discuss the future directions and research priorities in this rapidly developing field.

Awareness of interventional radiology and image guided musculoskeletal interventions among orthopaedic surgeons, rheumatologists, and physiatrists: A multi-site analysis

PURPOSE

Evaluate physicians who treat musculoskeletal (MSK) disorders in their knowledge of image-guided MSK interventions, and identify areas that could benefit from education.

MATERIALS AND METHODS

A 17-question survey was distributed to orthopaedic surgeons, physiatrists, and rheumatologists in the 14-hospital health system. It inquired about demographics, practice environment, awareness of interventional radiology (IR) and MSK radiology (MSKR) training, referral patterns, and knowledge of image-guided MSK interventions.

RESULTS

In total, 59 of 303 physicians completed the survey (41% orthopaedists, 35% physiatrists, and 24% rheumatologists). Most (93%) were attendings and 41% were female. A minority of survey respondents (17%) recognized the designation of IR as a distinct specialty of medicine per the American Board of Medical Specialties, in contrast to MSKR, which is not designated as a distinct specialty. When queried about IR procedures not under investigation, 24% selected genicular artery embolization and 31% selected embolization for adhesive capsulitis. Barriers to referral were as follows: 21% of specialists performed the procedure, 17% listed electronic medical record challenges, 14% reported scheduling difficulty, 13% reported no barriers, 11% reported difficulty consulting, 11% referred to another specialty, 10% did not have enough knowledge of image guided procedures, and 3% reported the procedure is not performed by IR or MSKR.

CONCLUSIONS

Survey data reveal a knowledge gap among surveyed physicians regarding IR as a specialty as well as areas of IR research in MSK disorders. Findings suggest areas where referring physicians can be educated and identify barriers to referral.

Genicular Artery Embolization for Knee Osteoarthritis: A Comprehensive Review

» Genicular artery embolization (GAE) is a promising treatment option for patients with knee osteoarthritis who are unresponsive to nonsurgical treatments and not yet candidates for surgery.» Current evidence supports the effectiveness of GAE in reducing pain and synovitis, with few reported major adverse events.» The cost-effectiveness and long-term results of GAE compared with other treatment options require further investigation.» Limitations of existing studies include small sample sizes, single-center trials, and lack of comparison between embolic agents and other treatments.» Future research should focus on larger, multicenter trials with longer follow-up periods and head-to-head comparisons with alternative treatment modalities to establish the role of GAE in the management of knee osteoarthritis.

Genicular Artery Embolization as a Treatment for Osteoarthritis Related Knee Pain: A Systematic Review and Meta-analysis

OBJECTIVE

Genicular artery embolization (GAE) is a minimally invasive therapy for symptomatic osteoarthritis (OA) in patients with knee pain refractory to conservative management. The purpose of this study was to evaluate evidence on the effectiveness of GAE for OA related knee pain as part of a systematic review and meta-analysis.

MATERIALS AND METHODS

Using Embase, PubMed, and Web of Science, a systematic review was performed to identify studies evaluating treatment of knee OA with GAE. The primary outcome measure was change in pain scale score at 6 months. A Hedge's g was computed as a measure of effect size, selecting Visual Analog Scale (VAS) first if available and Knee Injury and Osteoarthritis Outcome Score and Western Ontario and McMaster Universities Osteoarthritis Index if VAS was not available.

RESULTS

After screening titles, abstracts, and the full text, 10 studies met inclusion criteria. A total of 351 treated knees were included. Patients who underwent GAE demonstrated declines in VAS pain scores at 1 month {- 34 points [95% CI (- 43.8, - 24.6)], 3 months {- 30 points [95% CI (- 41.7, - 19.2)], 6 months {- 41 points [95% CI (- 54.0, - 27.2)], and 12 months {- 37 points [95% CI (- 55.0, - 18.1)]. Hedges' g from baseline to 1, 3, 6, and 12 months, was {- 1.3 [95% CI (- 1.6, - 0.97)]}, {- 1.2 [95% CI (- 1.54, - 0.84)]}, {- 1.4 [95% CI (- 2.1, - 0.8)]}, and {- 1.25 [95% CI (- 2.0, - 0.6)]}, respectively.

CONCLUSION

GAE provides durable reductions in pain scores for patients suffering with mild, moderate, and severe OA.

Genicular Artery Embolization for Primary Knee Osteoarthritis

Genicular artery embolization (GAE) is a novel treatment for knee osteoarthritis (OA) with increasing interest and utilization worldwide. The genicular arteries are selectively embolized using microspheres with subsequent cessation of abnormal synovial hyperemia, a process believed to arrest the inflammatory changes and pain associated with OA. Current data indicate that GAE offers sustained, 6-month improvement in Western Ontario and McMaster Universities Osteoarthritis index (WOMAC) and visual analog scale scores in 80 to 85% of patients with mild to moderate OA. As GAE gains traction, future studies are needed to establish its safety and efficacy relative to placebo and other standard-of-care therapies while also characterizing populations for which it is most effective.

Intraarticular STP Radiofrequency for Painful Osteoarthritis in the Knee: A Retrospective Single Center Analysis

OBJECTIVE

Osteoarthritis (OA) is the most common cause of chronic knee pain, often a debilitating condition that can cause a significant reduction in functional capacity. Radiofrequency is a form of neuromodulation that modulates pain signal transmission and has become progressively more common as a treatment for knee pain. This retrospective study aims to evaluate the efficacy of intraarticular radiofrequency in patients with chronic knee OA pain.

MATERIALS AND METHODS

In this retrospective study, we included 129 patients undergoing intraarticular pulsed radiofrequency using the Poisson curve for energy distribution (Sluijter-Teixeira Poisson radiofrequency) (STP) from March 2018 to November 2019. Knee osteoarthritis severity was assessed prior to the procedure using the Lequesne Index, classifying patients into six groups based on level of severity. Pain intensity was assessed through a 10-cm visual analog scale (VAS), and level of patient satisfaction was assessed through a questionnaire.

RESULTS

In the sample, pain reduction as measured by VAS compared to baseline prior to the procedure was statistically significant immediately following the procedure, at 30 days and at 90 days (p<0.001); this difference was less significant at 180 days (p<0.005). Efficacy in patients with moderate to severe disability was considerably greater than in patients with very severe to extremely severe disability. 57.36% reported that they were very satisfied, 29.46% satisfied, 9.3% neither satisfied nor dissatisfied, 2.33% dissatisfied, and 1.55% very dissatisfied.

CONCLUSION

Our results suggest that STP radiofrequency may be a safe and effective procedure for knee OA, able to significantly reduce VAS scores at 1 month and 3 months compared to baseline. Based on our results, a key factor to consider when treating knee OA with STP radiofrequency is that it is more effective among patients with a lower level of disability. Due to the retrospective observational study design, prospective longitudinal investigation is required to further support the recommendation of STP radiofrequency for knee OA.