Genicular Nerve Radiofrequency Ablation for the Treatment of Chronic Knee Pain: Systematic Review with Bayesian Network Meta-Analysis.

The average age of our population is increasing, resulting in a high incidence of chronic degenerative knee pathologies. Several treatment options, including surgical procedures are available to help mitigate these pathologies. However, the percentage of subjects with chronic post-surgical knee pain is still estimated at 16–20%. Neuromodulation techniques such as spinal cord stimulation and dorsal root ganglion stimulation (DRGS) are treatment options for subjects with chronic knee pain. The evidence for peripheral nerve stimulation (PNS) is minimal due to a limited number of neuromodulation systems capable of targeting the distal part of the lower limbs. This study aimed to investigate the safety and efficacy externally powered PNS systems for the treatment of chronic intractable knee pain targeting the saphenous nerve. Patients suffering from chronic intractable post-surgical knee pain received landmark-guided peripheral nerve stimulation of the branches of the saphenous nerve. All implants were performed with an externally powered PNS system to avoid lead migration as a result of cross-joint lead positions tunneling towards an Implantable Pulse Generator to the trunk. Data were collected retrospectively. Subject-reported outcome was measured via numerical rating scale values on a 10-point scale measuring pain intensity at rest and in motion. Additional data were collected for the subjects treated at the Charité location, including quality of life with the SF-36 form, quality of sleep with the Pittsburgh Sleep Quality Index and mood states with the short form of the General Depression Scale. Thirty-three patients received direct to permanent implant, landmark-guided peripheral nerve stimulation of the saphenous nerve branches. Six (18.2%) subjects reported non-sufficient initial benefit from the therapy and were explanted. Two subjects were explanted due to wound infections. The total study population reported included 25 patients. These subjects reported significant improvements related to pain, quality of life, mood quality, and quality of sleep. Additionally, subjects were able to reduce their opioid medication significantly after PNS therapy. Externally powered PNS at the saphenous nerve branches is a straightforward, selective and safe technique for patients with chronic knee pain. The landmark-guided implantation technique is less invasive than classical neuromodulation techniques such as spinal cord or DRGS and complication rates remain low. Short-term results are promising and show considerable reductions in pain scores and opioid intake. Long-term results are pending.

Introduction: Radiofrequency Ablation (RFA) has a long history dating back to 1931, with applications in treating various pain conditions. Given its established efficacy in managing spinal facet joint pain and its emerging popularity in treating arthritic knee pain through Genicular Nerve RFA (GNRFA), it is essential to investigate the effectiveness of traditional RFA in alleviating knee pain due to degenerative Osteoarthritis (OA) in patients with advanced OA who are not candidates for Total Knee Arthroplasty (TKA). Aim: To evaluate the effectiveness of RFA of genicular nerves in reducing chronic knee pain due to degenerative OA. Materials and Methods: This prospective interventional study was conducted at the Department of Orthopaedic Surgery, JSS Medical College, Mysore, Karnataka, India over a period of one year from July 2022 to June 2023. A total of 38 patients with chronic knee pain resulting from degenerative OA underwent RFA of genicular nerves, with assessments conducted at four time points: baseline, one month, three months and six months postprocedure. The evaluations utilised the Numerical Rating Scale (NRS) to measure pain levels, the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) to evaluate functional outcomes, and monitored analgesic usage to track pain management, providing a comprehensive understanding of the treatment’s effectiveness in alleviating chronic knee pain. The Friedman test was used to study the effectiveness of RFA of genicular nerves in reducing knee pain due to degenerative OA, and the pairwise Wilcoxon test with Bonferroni correction was used to compare statistical significance between different pairs. A p-value of <0.05 was considered statistically significant. Results: Substantial reductions were noted in pain levels, both at rest and during movement, as evidenced by significant reductions (p-value <0.001) in NRS scores, alongside improvements in WOMAC scores and decreased analgesic usage at all follow-up assessments compared to baseline (p-value <0.05). Conclusion: The study found that GNRFA significantly reduces pain and improves function in patients with chronic knee OA. This minimally invasive procedure is a safe, effective and costefficient treatment option for OA patients who rely heavily on analgesics, are unsuitable for surgery, or experience persistent pain after Total Knee Replacement (TKR).

Genicular nerve radiofrequency ablation (RFA) for the treatment of chronic knee pain has traditionally targeted the superomedial, superolateral, and inferomedial genicular nerves. However, recent cadaveric studies of knee neuroanatomy demonstrate varied locations of these specific nerves as well as additional articular nerves. This work suggests that traditional genicular nerve RFA lesion locations may be inadequate. 1) To describe a novel protocol utilizing a three-tined RFA electrode to target the superomedial (SMGN), superolateral (SLGN), and inferomedial genicular nerves (IMGN), as well as the terminal articular branches of the nerves to the vastus medialis (NVM), intermedius (NVI), and lateralis (NVL). 2) To assess the ability of this technique to reduce chronic knee pain. Case series of consecutive patients with six or more months of refractory knee pain who underwent genicular nerve RFA according to the novel protocol described. Seven discrete RFA lesions were placed to target the SMGN, NVM, NVI, NVL, SLGN, and IGMN. Eleven patients underwent RFA, nine with knee osteoarthritis and two postarthroplasty. At one month, 91% (95% CI = 59-100%), 82% (95% CI = 48-98%), and 9% (95% CI = 2-41%), of patients reported ≥50%, ≥80%, and 100% improvement in knee pain on the numeric rating scale, respectively. These results were sustained at six months. There were no complications. These preliminary data suggest the feasibility and possible effectiveness of genicular nerve RFA using the described novel protocol including a three-tined electrode. Larger-scale studies with comparative groups are warranted.

Chronic knee pain is the second most common cause of chronic pain in the United States. Occasionally, patients become refractory to conventional treatments such as intraarticular cortisone injections and viscosupplementation. Patients who have exhausted these therapies or have a contraindication to the therapies may be candidates for diagnostic genicular nerve block and if successful, subsequent radiofrequency ablation (RFA). For patients who have undergone image-guided genicular nerve radiofrequency ablation with fluoroscopic or ultrasound guidance without success, an endoscopic approach can be used as an alternative modality with success. With direct visualization of the genicular nerves, the likelihood of success with an endoscopic approach increases as some patients can have varying anatomy of the genicular nerves for which cannot always be detected with fluoroscopy or ultrasound. The purpose of this study is to demonstrate the utilization of a direct endoscopic approach for genicular nerve RFA for patients with chronic knee pain that have failed to improve after image-guided genicular RFA with fluoroscopic or ultrasound guidance. Two patients who had underwent successful diagnostic genicular nerve blocks were assessed for pre-procedure and post-procedure visual analog scale (VAS) scores following endoscopic genicular nerve RFA after failure of the conventional image guided approach at 6 and 12 months. Both patients reported greater than 80% reduction in VAS score and improvement in function at 6 and 12 months Limitations of the current study is a limited number of patients, and lack of the use of a formal functional scale to demonstrate improvement. Ultimately, the conclusion was drawn that an endoscopically-guided genicular nerve RFA can be utilized successfully due to direct visualization of the genicular nerves when conventional approaches with Fluoroscopic/ultrasound guidance has failed to achieve analgesia and functional improvement. Key words: Genicular nerve block, endoscopic, radiofrequency ablation. knee pain, chronic osteoarthritis, genicular neuritis, genicular neuralgia, total knee arthroplasty, arthritis

ObjectiveTo assess long‐term outcomes of cooled radiofrequency ablation (CRFA) of genicular nerves for chronic knee pain due to osteoarthritis (OA).MethodsA prospective, observational extension of a randomized, controlled trial was conducted on adults randomized to CRFA. Subjects were part of a 12‐month clinical trial comparing CRFA of genicular nerves to a single hyaluronic injection for treatment of chronic OA knee pain, who then agreed to visits at 18‐ and 24‐months post CRFA and had not undergone another knee procedure since. The subjects were evaluated for pain using the Numeric Rating Scale (NRS) function using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), subjective benefit using the Global Perceived Effect (GPE) scale, quality of life using the EuroQol‐5‐Dimensions‐5 Level (EQ‐5D‐5L) questionnaire, and safety.ResultsOf 57 subjects eligible, 36 enrolled; 32 completed the 18‐month visit with a mean NRS score of 2.4 and 22 (69%) reporting ≥50% reduction in pain from baseline (primary endpoint); 27 completed the 24‐month visit, with a mean NRS of 3.4 and 17 (63%) reporting ≥50% pain relief. Functional and quality of life improvements persisted similarly, with mean changes from baseline of 53.5% and 34.9% in WOMAC total scores, and 24.8% and 10.7% in EQ‐5D‐5L Index scores, at 18‐ and 24‐months, respectively. There were no identified safety concerns in this patient cohort.ConclusionIn this subset of subjects, CRFA of genicular nerves provided durable pain relief, improved function, and improved quality of life extending to 24 months post procedure, with no significant safety concerns.

Background: Osteoarthritis (OA) is one of the most common chronic type of arthritis affecting the adult population. Symptomatic knee OA affects 6% of the adult population and occurs in 10% of adult of 65 years and older. Radiofrequency ablation (RFA) has been used for the variety of chronic pain when conservative therapies failed. Genicular nerve RFA is a treatment modality for OA knee patients, especially when surgery is contraindicated due to advanced medical problems or when the patient is not willing to undergo surgery.Methods: This retrospective observational study was conducted in the Pain Management Section, Department of Anaesthesiology, Aga Khan University Hospital, Karachi. We included all patients who underwent diagnostic genicular nerve block for chronic knee pain between 1 June 2017 and 30 December 2018. Patients who underwent radiofrequency ablation of genicular nerves for chronic knee pain were recruited for this study. All enrolled patients were then followed for the next six months.Results: Twenty-eight patients with chronic knee pain were selected to undergo radiofrequency ablation (RFA) of genicular nerves. Seventy-five percent of the patients were female, the average age of the patients were 62.89 (±10.96) years, and the mean body mass index was 30.29 (±4.88) kg/m 2. The mean numerical rating pain (NRS) score was 7.4 (±1.03) before pain intervention and 2.8 (±1.07) after RFA of genicular nerves, which was statistically significant (p=0.0005). In our patient cohort, knee RFA was found to be effective in 23 patients (82.14%).Conclusion: This study reports 60-70% pain relief for six months in 82% of patients who underwent RFA of genicular nerves for severe osteoarthritis of knee joints.

Exercise as a Treatment for Chronic Pain

BACKGROUND: Chronic knee pain is highly prevalent in the United States, especially within the older population. The condition negatively impacts overall quality of life and can be a substantial financial burden. Current conservative and surgical interventions are not always effective in managing chronic knee pain. Peripheral nerve stimulation (PNS) can be an alternative to current management strategies. CASE REPORT: Data was retrospectively extracted from the electronic medical records of patients who received a permanent Freedom® PNS System for treating chronic knee pain. Systems were implanted for at least one month. Outcomes of interest included pain levels and occurrences of adverse events. Seven patients were included in this analysis. Pain scores decreased from 9.8 ± 0.3 to 1.6 ± 1.5 after the trial. The average pain score was 1.3 ± 0.8 at one month, with no adverse events reported. CONCLUSIONS: Chronic knee pain can be safely managed with the Freedom PNS System. KEY WORDS: Peripheral nerve stimulation, chronic pain, CRPS, infrapatellar saphenous neuralgia

Background Chronic knee pain represents a major cause of disability and a burden on healthcare systems worldwide, being more prevalent in middle-aged and elderly patients. It can take a toll on patients’ daily life, keeps them from their favorite activities, saps of productivity, and diminishes overall quality of life. It can be caused by degenerative conditions, such as osteoarthritis (the most common cause), rheumatoid arthritis, crystalline arthritis and gout. lifestyle modification, pharmacologic management, and injections are the mainstay of therapy for elderly patients having chronic symptomatic knee pain with multiple medical comorbidities who do not wish/fit for surgical options. Intra-articular corticosteroid injection (IACSI) was commonly adopted to alleviate chronic knee pain and was traditionally performed blindly depending only on anatomical land marks. Recently, Genicular nerve block (GNB) has recently emerged as a novel alternative treatment for chronic knee pain. Both Intra-articular corticosteroid injection (IACSI) and Genicular nerve block (GNB) can be carried out under Ultrasound guidance as a safer, cheaper and more feasible imaging modality for guidance as it provides real-time imaging for the knee structures in a dynamic manner giving the ability to do interventional procedures and providing more effective clinical results when compared to blind injections. Aim of the Work Illustrate the technical aspects, the indications and the methodology of local therapies for chronic knee pain performed by interventional radiologists and provide current evidence. Assess the efficacy of Ultrasound (US) guided intraarticular corticosteroids injection and Genicular nerve block to control moderate and advanced chronic knee pain. Compare the immediate and short-term symptomatic and functional improvement obtained after both techniques. Patients and Methods The study was carried out on 30 patients of symptomatic chronic knee pain with radiologically proven knee joint arthritis (26 of them had osteoarthritis, 3 had gout arthritis and one patient had rheumatoid arthritis), all of them were not responding to medical treatment. They were divided into two groups (intraarticular corticosteroids injection group and Genicular nerve block one) both procedures were performed under ultrasound guidance to identify target points for injection. GNB target points for injection where close to the superior lateral, superior medial and inferior medial genicular arteries while target point for the IACSI group was the suprapatellar bursa. All procedures were performed with a spinal needle (22 G) introduced under ultrasound guidance till reaching the desired target points at both groups. Then injection of a mixture of Lidocaine, Bupivacaine hydrochloride and Triamcinolone Acetonide was done. Results In our study, in IACSI group the mean of initial VAS was 80.7±10.3 compared to 81.3±7.7 in GNB group. The mean VAS significantly dropped to be 20.7±5.3 in IACSI group compared to 18.3±5.9 in GNB group. After 2 weeks, it was 34.3±8.4 and 27.7±8.2 respectively. After 4 weeks, it increased to 40±8.7 and 33.7±9.3 respectively. At 8 weeks, it was obviously increased to 75.3±10.3 and 66.7±11.4 respectively and the effect returned gradually till nearly the baseline at 8 weeks. In our study, in IACSI group the mean of initial OKS was 48.6±7.4 compared to 50.1±7.6 in GNB group. After 2 weeks, it was markedly decreased to 25.5±3.9 and 22.7±6.8 respectively. After 4 weeks, it increased to 31.1±3.5 and 27.±6.9 respectively. At 8 weeks, it was obviously increased to 44.1±7.1 and 39.3±6.1 respectively and the effect returned gradually till nearly the baseline at 8 weeks. Conclusion Ultrasound guided genicular nerve block with a mixture of corticosteroid and local anesthetic is an effective, radiation free method to alleviate chronic knee pain and improve knee joint function. US guided intra-articular corticosteroid injection through suprapatellar approach is also an effective method to relive chronic knee pain and inflammation and to improve knee joint functional capacity. Both procedures are effective in alleviation of chronic knee pain for up to 4 weeks with marked decrease in VAS score after 2 weeks and slight increasing trend towards 4 weeks. The favorable effect returned gradually till nearly the baseline at 8 weeks. Genicular nerve block is more effective than intra-articular corticosteroid injection in both pain alleviation and improving knee joint function. The earlier the Kellgren- Lawrence score is, the more reduction in chronic knee pain and the more improvement of joint function is achieved after both procedures.

Genicular nerve radiofrequency ablation practice patterns: A survey study of the International Pain and Spine Interventional Society

Genicular nerve radiofrequency ablation (GNRFA) is an effective treatment for chronic knee pain. However, there has been minimal investigation of real-world, long-term outcomes and factors that predict treatment success after GNRFA. To evaluate the effectiveness of GNRFA for chronic knee pain in a real-world population and identify predictive factors. Consecutive patients who underwent GNRFA at a tertiary academic center were identified. Demographic, clinical, and procedural characteristics were collected from the medical record. Outcome data were numeric rating scale (NRS) pain reduction and Patient Global Impression of Change (PGIC). Data were collected by standardized telephone survey. Predictors of success were evaluated with logistic and Poisson regression analyses. Of the 226 total patients identified, 134 (65.6 ± 12.7; 59.7% female) were successfully contacted and analyzed, with a mean follow-up time of 23.3 ± 11.0 months. Of those, 47.8% (n = 64; 95%CI: 39.5%-56.2%) and 61.2% (n = 82; 95%CI: 52.7%-69.0%) reported ≥50% NRS score reduction and ≥2-point NRS score reduction, respectively, and 59.0% (n = 79; 95%CI: 50.5%-66.9%) reported "much improved" on the PGIC questionnaire. Factors associated with a greater likelihood of treatment success (P < .05) were higher Kellgren-Lawrence osteoarthritis grade (2-4 vs 0-1); no baseline opioid, antidepressant, or anxiolytic medication use; and >3 nerves targeted. In this real-world cohort, approximately half of the participants experienced clinically meaningful improvements in knee pain after GNRFA at an average follow-up time of nearly 2 years. Factors associated with higher likelihood of treatment success were more advanced osteoarthritis (Kellgren-Lawrence Grade 2-4); no opioid, antidepressant, or anxiolytic medication use; and >3 nerves targeted.

Introduction. Chronic pain defines as pain persisting for three months or longer, chronic post-surgical pain can affect all dimensions of health-related quality of life, and is associated with functional limitations. treatment of chronic pain after total knee replacement is challenging, and evaluation of combined treatments and individually targeted treatments matched to patient characteristic. Genicular nerve block radiofrequency ablation is a safe and effective therapeutic procedure for pain associated with chronic pain due to knee osteoarthritis, and the evolution of newer regional analgesia techniques aids in reducing postoperative pain Dual Subsartorial Block (DSB) as a procedure specific, post total knee replacemet. historically there has been a reliance on using a pain-spesific assessment tools Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC)&#x0D; Case Presentation. A 55-year old woman admitted she had pain on bilateral knee, the knee pain had affected her daily living, she was diagnosed with chronic knee pain post TKR because of osteoarthritis genu bilateral, the patient was planning genicular nerve radiofrequency ablation and dual subsartorial block, from the examination we found that numeric rating scale was 6 (moderate pain) with WOMAC score 76, before the procedure the patients are examined through radiology for any deformity in the knee. The genicular nerve radiofrequency ablation under ultrasound guidance on bonylandmark, resulting anesthesia of the anterior compartment of the knee, and dual subsartorial block that cover almost all the innervations of pain generating component of the anterior and posterior knee joint involved in TKR surgery. After the procedure we reevaluated the pain score using NRS was 2 (mild pain), and with WOMAC Score 19.&#x0D; Conclusion. Treatment of chronic pain post total knee replacemet was challenging, targeted treatment may ameliorate the pain and prevent long term disability.&#x0D;

Persistent pain is one of the most frequent complications following total knee arthroplasty (TKA) and can be devastating for the patient's quality of life. The use of genicular nerve radiofrequency ablation (GNRFA) is prevalent regarding non-surgical treatment of knee osteoarthritis. However, it is controversial when employed for the management of residual pain after TKA. This study aims to evaluate the efficacy of GNRFA for the treatment of post-TKA chronic pain and to assess the potential benefits of its use. Twelve patients sustaining chronic pain after TKA underwent GNRFA treatment. The intervention included the superior medial genicular nerve, the superior lateral genicular nerve and the inferior medial genicular nerve. Visual analog scale (VAS) system was utilized for pain assessment at 1-week, 6-month, and 1-year follow-ups. Patients experiencing chronic knee pain derived from other or unspecified causes were excluded. Mean VAS score before the treatment was 8.3, while it ended up 2.3, 5.7, and 7.9 at the 1-week, 6-month, and 1-year follow-up, respectively. Some patients reported residual pain that they regarded more bearable than before the procedure at the 1-week evaluation, with no significant alterations in the 6-month reassessment. In 2 cases results at the 1-week follow-up were dissatisfying, however, this aided us in distinguishing the cause of the persistent pain. We were not able to conclude that GNRFA used for the treatment of chronic pain after TKA is as efficacious as in knee osteoarthritis pain. However, in some cases, it proved to be beneficial regarding discerning the etiology of the pain.

Background: Studies of radiofrequency ablation (RFA) of genicular nerves have reportedly significantly decreased pain up to 3 months post ablation, but no longer term effects have been reported. We performed an analysis of long-term pain relief of 31 RFA procedures of the genicular nerves to analyze the degree of pain relief past 3 months, culminating at 6 months. Objective: To evaluate the long term efficacy of genicular nerve ablation for management of chronic knee pain due to osteoarthritis. Study Design: Chart review and study design was approved by Newark Health Sciences IRB. Chart review and follow-up was performed on all patients who underwent genicular nerve RFA during the period of February 2014 through August of 2015. During this inclusion period 41 genicular nerve RFAs were performed on 31 patients, 5 patients received RFA procedure in both knees. Patient follow-up was performed via telephone interview or in-office visit at least 3 months and 6 months post RFA. Settings: Procedures were performed in Medical Special Procedures at University Hospital in Newark, NJ, and the Pain Management Center at Overlook Medical Arts Center in Summit, NJ. Methods: Chart review and study design was approved by Newark Health Sciences Institutional Review Board. Chart review was performed from February 2014 and continued through August 2015. Patient follow-up was conducted at 3 and at least 6 months post treatment to gauge degree of pain relief (0 – none, 100% – complete), their current day’s pain score, other treatment modalities tried before RFA, and the medications used. Patients were asked to quantify their satisfaction with procedure length, pre-procedure anxiety, complications, and if they would recommend this procedure to others. Primary and secondary goals were the duration of pain relief after RFA, the quality of pain relief, and the efficacy of our approach for RFA of genicular nerves versus prior published techniques. Results: At 3 month follow-up, the average pain relief was 67% improvement from baseline knee pain, 0% being no relief and 100% being complete relief, and average 0 – 10 pain score was 2.9. At 6 month follow-up, of those who described pain relief at 3 months, 95% still described pain relief. This group’s average percent pain relief was 64% and average day’s 0 – 10 pain score 3.3. Limitations: Our study included a retrospective component in chart review followed by prospective follow-up, only 76% of patients were able to participate in the interview process. Furthermore, some patients suffered from other chronic pain ailments, most commonly chronic back pain, which at times disturbed the patient’s ability to focus on solely knee pain. Conclusions: Based on patient interviews and data collection, RFA of genicular nerves can supply on average greater than 60% pain relief in our patient population for as long as 6 months. Key words: Osteoarthritis, knee osteoarthritis, chronic knee pain, radiofrequency ablation, nerve ablation, genicular nerves, long-term pain relief

The effectiveness and safety of three genicular nerve radio frequency ablation (GNRFA) in the management of knee osteoarthritis (KOA) has been replicated in systematic reviews; however, no standardized protocol exists.[1][1]...