Advanced 3D Anatomical Mapping of Saphenous and Inferior Medial Genicular Nerve Branching: Enhancing Precision in Knee Joint Denervation.

BACKGROUND: Radiofrequency ablation is a common non-opioid treatment to manage chronic knee pain. The inferior medial genicular nerve is conventionally targeted. It has been suggested that the infrapatellar branch(saphenous nerve) should also be targeted. There is controversy regarding the contribution of the infrapatellar branch to the innervation of the knee joint capsule. OBJECTIVE: 1) Identify the frequency of the branching pattern(s) of the infrapatellar branch in 3D; 2) Assess spatial relationships of branches of infrapatellar branch to the inferior medial genicular nerve; 3) Determine if capturing infrapatellar branch could result in additional benefit to the existing protocol. DESIGN: Anatomical Study. METHODS: The infrapatellar branch and inferior medial genicular nerve were serially dissected, digitized, and modelled in 3D in 7 specimens(mean age 57.8 ± 2.0; 2F/5M) and their relationship documented. The spatial relationship of the nerves was used to assess the anatomical efficacy of including the infrapatellar branch in the protocol. RESULTS: The infrapatellar branch is most frequently a cutaneous nerve. This nerve was variable and found to be unbranched or have 2-3 branches and in all specimens was located superficial to the branches of inferior medial genicular nerve. When the infrapatellar branch (1) coursed more distally, the strip lesion would not capture the infrapatellar branch but would capture inferior medial genicular nerve consistently;(2) overlapped with the inferior medial genicular nerve, the strip lesion would capture both nerves. CONCLUSIONS: Proposed protocol targeting the infrapatellar branch is likely to capture the inferior medial genicular consistently regardless of the anatomical variation of the infrapatellar branch.

Novel use of motor-sparing genicular nerve blocks for knee injuries in the emergency department.

Knee injuries are quite prevalent in the Emergency Department (ED) and often present with severe pain, necessitating effective pain management strategies. Traditional pain management approaches, including opioid medications, may carry undesirable side effects and potential risks, leading to the growing interest in non-opioid alternatives. Nerve blocks have emerged as promising options for targeted pain relief in the ED. Motor-sparing nerve blocks have gained importance due to their ability to provide effective analgesia without compromising motor function [1]. The case series demonstrates the successful use of ultrasound-guided genicular nerve blocks(GNB) in the Emergency Department, providing targeted pain relief without compromising motor function. GNBs offer a valuable alternative to traditional nerve blocks(femoral, fascia iliaca, adductor canal) and opioid-based pain control strategies in the ED. As the evidence base grows, GNBs may become a more established component of ED pain management protocols, enhancing patient outcomes and safety in the management of acute knee injuries. The incorporation of ultrasound-guided motor-sparing nerve blocks in ED pain management protocols may hold great promise in optimising pain control and enhancing patient comfort. Trial Registration: N/A.

Genicular nerve radiofrequency ablation for the treatment of chronic knee joint pain: a real-world cohort study with evaluation of prognostic factors.

BACKGROUND: 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. OBJECTIVES: To evaluate the effectiveness of GNRFA for chronic knee pain in a real-world population and identify predictive factors. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Can ultrasound-guided radiofrequency ablation of genicular nerves of the knee, be performed without locating corresponding arterial pulsations-a cadaveric study.

INTRODUCTION: Given the rising prevalence of knee osteoarthritis, radiofrequency ablation of genicular nerves (RFA) has emerged as a promising treatment option for knee pain. The knee has an extremely complex and variable innervation with nearly 13 genicular nerves described. The frequently ablated genicular nerves are the superomedial (SMGN), the superolateral (SLGN), and the inferomedial (IMGN) genicular nerves. Conventionally, under ultrasound guidance, these nerves are ablated near the corresponding arterial pulsations, but due to the rich vascular anastomosis around the knee joint, identifying the arteries corresponding to these constant genicular nerves can be tedious unless guided by some bony landmarks. In this study, we have evaluated whether it is possible to accurately target these three genicular nerves by just locating bony landmarks under ultrasound in human cadaveric knee specimens. METHODS: Fifteen formalin-fixed cadaveric knee specimens were studied. SMGN was targeted 1 cm anterior to the adductor tubercle in the axial view. For SLGN, in the coronal view, the junction of the lateral femoral condyle and shaft was identified, and at the same level in the axial view, the crest between the lateral and posterior femoral cortex was targeted. For IMGN in the coronal view, the midpoint between the most prominent part of the medial tibial condyle and the insertion of the deep fibers of the medial collateral ligament was marked. The medial end of the medial tibial cortex was then targeted at the same level in the axial view. The needle was inserted from anterior to posterior, with an in-plane approach for all nerves. Eosin, 2% W/V, in 0.1 ml was injected. Microdissection was done while keeping the needle in situ. Staining of the nerve was considered a positive outcome, and the percentage was calculated. The nerve-to-needle distance was measured, and the mean with an interquartile range was calculated. RESULT: The accuracies of ultrasound-guided bony landmarks of SMGN, SLGN, and IMGN were 100% in terms of staining, with average nerve-to-needle distances of 1.67, 3.2, and 1.8 mm respectively. CONCLUSION: It is with 100% accuracy, that we can perform RFA of SMGN, SLGN, and IMGN under ultrasound guidance, by locating the aforementioned bony landmarks.

Functional Outcomes and Physical Performance of Knee Osteoarthritis Patients After Ultrasound-Guided Genicular Nerve Radiofrequency Ablation.

OBJECTIVE: To elucidate the effectiveness of ultrasound-guided genicular nerve radiofrequency ablation in alleviating pain as well as its effects on functional outcomes, quality of life and physical performance in knee osteoarthritis patients. DESIGN: Prospective observational study. SETTING: Patients were recruited within one community hospital. SUBJECTS: Patients with knee osteoarthritis. METHODS: The subjects underwent ultrasound-guided radiofrequency ablation of genicular nerves after showing a positive response to a diagnostic block. Outcome assessments were performed at baseline and at 2 and 12 weeks posttreatments using the 36-item Short Form Health Survey (SF-36), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and a physical performance evaluation including balance tests, quadriceps muscle strength test, two-minute walking test and knee joint proprioception test. RESULTS: Thirteen out of 38 patients were eligible for genicular nerve radiofrequency ablation. There were significant improvements from baseline to posttreatment in the numeric rating scale score, physical health domain score of SF-36, and pain and stiffness domain scores of the WOMAC. Regarding physical performance, the step test result significantly improved over the 12 weeks of follow-up. On the other hand, no significant deteriorations in the single leg stance test, isokinetic quadriceps muscle strength test, knee joint proprioception test or two-minute walking test results were observed after radiofrequency ablation of genicular nerves. CONCLUSIONS: Radiofrequency ablation of genicular nerves may significantly alleviate pain and improve functional outcomes in knee osteoarthritis patients. More importantly, static balance control and quadriceps muscle strength were preserved and there was a change of proprioception in the good direction.

Management of Refractory Pain After Total Joint Replacement.

PURPOSE OF REVIEW: Chronic pain after total joint replacement (TJA), specifically total knee replacement (TKA), is becoming more of a burden on patients, physicians, and the healthcare system as the number of joint replacements performed increases year after year. The management of this type of pain is critical, and therefore, understanding the various modalities physicians can use to help patients with refractory pain after TJA is essential. RECENT FINDINGS: The modalities by which chronic pain can be successfully managed include genicular nerve radioablation therapy (GN-RFA), neuromuscular electrical stimulation (NMES), transcutaneous electrical nerve stimulation (TENS), and peripheral subcutaneous field stimulation (PSFS). Meta-analyses and case reports have demonstrated the effectiveness of these treatment options in improving pain and functional outcomes in patients with chronic pain after TKA. The purpose of this paper is to review and synthesize the current literature investigating the different ways that refractory pain is managed after TJA, with the goal being to provide treatment recommendations for providers treating these patients.

Novel Use of 3-Point Genicular Nerve Block for Acute Knee Pain in the Emergency Department.

BACKGROUND: Ultrasound-guided genicular nerve blocks (GNBs) in the emergency department (ED) have easily identifiable anatomic targets and offer an opportunity to provide safe, effective, motor-sparing analgesia for acute knee pain. Case Report A 68-year-old woman presented with acute, 8/10 right knee pain due to an isolated right lateral tibial plateau fracture. After informed consent and with the ultrasound in the sagittal plane, the superior lateral (SLGN), superior medial (SMGN), and inferior medial (IMGN) genicular nerves were identified at the junction of their respective femoral or tibial epicondyle and femoral or tibial epiphysis. The skin was anesthetized and an echogenic needle was inserted under ultrasound guidance to inject 1.0 mL of 0.5% bupivacaine around the right SLGN, SMGN, and IMGN. Approximately 30 minutes after the GNBs, the patient reported 0/10 pain at rest and 1/10 pain with movement. She did not require opioids during her ED visit or upon discharge. Why Should an Emergency Physician Be Aware of This? GNBs show promise as a useful tool to provide acute and medium-term motor-sparing analgesia in a patient with acute knee pain. GNBs have easy-to-recognize anatomic targets on ultrasound and may be a suitable adjunct or alternative to a multimodal pain regimen in the emergency department.

Comparison of cooled and conventional radiofrequency applications for the treatment of osteoarthritic knee pain.

BACKGROUND AND AIMS: Osteoarthritis is a progressive degenerative joint disease that affects the joint cartilage and surrounding tissues. It has been determined that osteoarthritis-induced knee pain is the most common cause of physical disability in the elderly. MATERIAL AND METHODS: In this study, the genicular nerve RF treatments of patients with osteoarthritic knee pain conducted at the Sakarya University Training and Research Hospital in the algology clinic of the Anaesthesiology and Reanimation Department between January 2016 and December 2016 were retrospectively examined. The preoperative and postoperative 2nd, 6th, and 12th week visual analog scale (VAS) and Turkish validated Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores were recorded. In addition, any complications after the treatment and side effects (bleeding, neurological damage, infection, etc.) were recorded in the file. RESULTS: When the data of the patients were evaluated statistically, the preoperative VAS and WOMAC scores were found significantly decreased compared with the postoperative 2nd week, 6th week, and 12th week scores in patients who applied both conventional radiofrequency (RF) and cooled RF. However, there was no statistically significant difference between the two techniques. CONCLUSION: We found that both cooled and conventional RF techniques in genicular nerve ablation are similarly effective in reducing pain in patients with osteoarthritis-induced knee pain and improving patients' physical functions. The complication rates are very low and there was no superiority to each other.

Ultrasound-Guided Peripheral Nerve Stimulation for Knee Pain: A Mini-Review of the Neuroanatomy and the Evidence from Clinical Studies.

OBJECTIVES: Peri- and postoperative pain frequently develops after joint replacement for severe knee osteoarthritis. A continuous nerve block is commonly used for pain relief, but the risks of infection and catheter dislodgement should be considered. The present mini-review aimed to brief the innervation and neural sonoanatomy of the knee joint and summarize the newest evidence of peripheral nerve stimulation (PNS) use in the management of knee pain. METHODS: We used a systematic approach to search for relevant articles. We used the combination of "peripheral nerve stimulation" and "knee pain" as the key words for the literature search using the electronic database without language or article type restriction. The search period was from the earliest record to August 2019. RESULTS: The present review identified six studies, four of which were related to PNS for management of postoperative knee pain and two of which probed neuropathic pain. Most of the studies were either case series or case reports. Based on our search result, PNS is likely to be a feasible and safe treatment for knee pain, but its effectiveness remains uncertain. CONCLUSIONS: The present review reveals that PNS is feasible for the management of knee pain, especially in the postoperative period. The procedure is safe under ultrasound guidance used for proper placement of the electrodes near the target nerves. In the future, more prospective randomized controlled trials are needed to validate the effectiveness of PNS in acute and chronic knee pain.

Lower limb kinematics improvement after genicular nerve blockade in patients with knee osteoarthritis: a milestone study using inertial sensors.

BACKGROUND: Genicular nerve blockade is a possible treatment for patients with knee osteoarthritis. Pain relief and improvement in functioning is expected. This procedure could be of major interest for patients in low-income countries where total knee arthroplasty is not available for the population. This study aims at assessing the immediate benefits on pain, gait, and stairs kinematics after a genicular nerve blockade in patients suffering from knee osteoarthritis in Cameroun. METHODS: A prospective study was carried out on 26 subjects in Cameroun. A genicular nerve blockade was performed on 14 women with painful knee osteoarthritis grade 2-4. Lower limb joint angles were recorded with inertial sensors before and 1 h after injection. Patient-reported outcomes of pain and perceived difficulty were collected, as well as 10 m and 6 min walking tests. A reliability analysis of inertial sensors was performed on a sample of 12 healthy subjects by calculating the intraclass correlation coefficient and the standard error of measurement. RESULTS: Pain and perceived difficulty decreased significantly (p < 0.001). Cadence increased significantly in stairs climbing (upstairs: + 7.7 steps/min; downstairs: + 7.6 steps/min). There was an improvement for hip sagittal range of motion during gait (+ 9.3°) and pelvis transverse range of motion in walking upstairs (- 3.3°). Angular speed range of the knee in the sagittal plane and of the hip in the frontal plane increased significantly in stairs descent (+ 53.7°/s, + 94.5°/s). CONCLUSIONS: This study quantified improvement of gait and stair climbing immediately after a genicular nerve blockade in patients suffering from knee OA in Cameroon. This is the first study objectifying this effect, through wearable sensors. TRIAL REGISTRATION: Pan African Clinical Trial Registry, PACTR202004822698484 . Registered 28 March 2020 - Retrospectively registered.

Distribution of sensory nerves supplying the knee joint capsule and implications for genicular blockade and radiofrequency ablation: an anatomical study.

BACKGROUND: Despite their emerging therapeutic relevance, there are many discrepancies in anatomical description and terminology of the articular nerves supplying the human knee capsule. This cadaveric study aimed to determine their origin, trajectory, relationship and landmarks for therapeutic purpose. METHODS: We dissected 21 lower limbs from 21 cadavers, to investigate the anatomical distribution of all the articular nerves supplying the knee joint capsule. We identified constant genicular nerves according to their anatomical landmarks at their entering point to knee capsule and inserted Kirschner wires through the nerves in underlying bone at those target points. Measurements were taken, and both antero-posterior and lateral radiographs were obtained. RESULTS: The nerve to vastus medialis, saphenous nerve, anterior branch of obturator nerve and a branch from sciatic nerve provide substantial innervation to the medial knee capsule and retinaculum. The sciatic nerve and the nerve to the vastus lateralis supply sensory innervation to the supero-lateral aspect of the knee joint while the fibular nerve supplies its infero-lateral quadrant. Tibial nerve and posterior branch of obturator nerve supply posterior aspect of knee capsule. According to our findings, five constant genicular nerves with accurate landmarks could be targeted for therapeutic purpose. CONCLUSION: The pattern of distribution of sensitive nerves supplying the knee joint capsule allows accurate and safe targeting of five constant genicular nerves for therapeutic purpose. This study provides robust anatomical foundations for genicular nerve blockade and radiofrequency ablation.

Ultrasound-Guided Neurolysis of Six Genicular Nerves for Intractable Pain from Knee Osteoarthritis: A Case Series.

INTRODUCTION: Among the elderly population, chronic osteoarthritis of the knee joint is one of the leading causes of disability and causes considerable pain, joint stiffness, and functional limitations. Although knee replacement is a good option for advanced osteoarthritis, many patients could not undergo surgery due to comorbidities or other reasons. METHODS: Four patients with severe pain from grade 3 and 4 osteoarthritis of the knee had undergone ultrasound-guided alcohol neurolysis of the 6 genicular nerves after a positive genicular nerve block with local anesthetics. The demographics, pain intensity (NRS), Oxford Knee Score (OKS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and quality of life (SF-36) were analyzed. RESULTS: There was significant improvement in pain intensity at rest, on movement, and on weight bearing after the neurolysis and it has continued for 6 months (P < 0.05). The OKS and WOMAC score had improved from 7.75 ± 1.25 and 77.75 ± 4.34 at baseline, to 20.75 ± 1.70 and 56.25 ± 3.09 at 1 month, and to 18.25 ± 0.95 and 52.00 ± 2.16 at 6 months after the procedure, respectively (P < 0.05). There was also significant improvement in the quality of life after the procedure (P < 0.05). CONCLUSION: Ultrasound-guided alcohol neurolysis is a good alternative for patients having severe pain from knee osteoarthritis and provides significant pain relief for more than 6 months.

Which imaging method should be used for genicular nerve radio frequency thermocoagulation in chronic knee osteoarthritis?

This study aimed to perform genicular nerve RF neurotomy using two different imaging methods, fluoroscopy and ultrasound, and to compare the clinical effects and reliability of the two methods. Fifty patients with osteoarthritis were included in this study. Patients were randomly allocated into group 1 (fluoroscopy imaging) and group 2 (ultrasound imaging). Outcomes were measured using a pain scale (visual analog scale; VAS) and the Western Ontario and McMaster Universities (WOMAC) Index of Osteoarthritis. The application time in the ultrasound group (20.2 ± 6.4 min) was shorter than in the fluoroscopy group (25 ± 4.8 min) (p < 0.05). There was no difference in pain relief and functional status between the ultrasound and fluoroscopy groups. Decrease in VAS score and WOMAC total score in the first and third months was significant in both groups (p < 0.001). GNRFT under ultrasound guidance was easily applicable, safe and dynamic, and required no radiation to achieve the same benefit as the fluoroscopy-guided interventions.

Knee pain relief with genicular nerve blockage in two brain injured patients with heterotopic ossification.

BACKGROUND: Heterotopic ossification (HO) is the ectopic bone formation in non-osseous tissues. This study aimed to present two patients with traumatic brain injury (TBI) who had HO in knee joint and pain relief after genicular nerve blockage. Case 1: A 14-year-old patient with TBI was admitted with bilateral knee pain and limited range of motion. Physical examination and x-ray graphics revealed calcification which was diagnosed as HO. Ultrasonography (US) guided genicular nerve blockage was performed to both knees with 2 ml lidocaine and 1 ml betamethasone. VAS of pain was decreased to 30 mm from 80 mm. At 6-month follow-up, VAS of pain was still 30 mm. Case 2: A 29-year-old patient with TBI was admitted for rehabilitation. He had right knee pain and his pain was 80 mm according to VAS. Investigation revealed HO. US guided genicular nerve blockage was performed to the right knee and pain was decreased to 20 mm. DISCUSSION: US guided genicular nerve blockage can provide pain relief in HO and this technique may be effective and alternative for pain relief in patients with neurogenic knee HO to increase patient's compliance.

Radiofrequency Treatment of Genicular Nerves Using a Hybrid Technique.

BACKGROUND: Radiofrequency ablation of genicular nerves is recommended to ameliorate the pain of osteoarthritis of the knee. However, long-term efficacy in patients with persistent pain following total knee arthroplasty remains elusive. The current study aimed to evaluate radiofrequency ablation of genicular nerves using a hybrid technique to manage severe incapacitating pain and quality of life following surgery. METHODS: This prospective, observational study included patients suffering from intractable knee pain with scores > 4 on the Numeric rating scale after 6 months of total knee arthroplasty. Therapy included radiofrequency ablation of the superior medial, lateral, and inferior medial genicular nerves using a hybrid technique. The Numeric rating scale and Oxford Knee Score for quality of life were assessed before therapy and at 1-, 3- and 6 months following treatment. RESULTS: Average pain scores reduced from 8.4 ± 1.3 (admission) to 3.3 ± 1.4 (1 month; p= <0.001) but subsequently started to increase to 4 ± 1.2 (3 months; p = 0.58), and 5.6 ± 0.9 (6 months; p= <0.001). Average Oxford Knee Score significantly improved from 14.2 ± 5.9 (admission) to 38 ± 8.6(1 month); p= <0.001, but these too subsequently reduced to 36.4 ± 7.9 (3 months); p= 1, and 22.5 ± 12.5(6 months); p= <0.001. CONCLUSIONS: Ultrasound-guided radiofrequency ablation of genicular nerves diminishes intractable pain and disability in patients with chronic knee pain following total knee arthroplasty. Treatment is safe and effective, however, the benefit declined by 6 months. A repeat block would be necessary if the pain score worsens.

Efficacy of Cooled-Radiofrequency Ablation of the Genicular Nerve as Treatment for Chronic Knee Pain: A Retrospective Study.

INTRODUCTION: Chronic pain is one of the leading causes of reduced quality of life in the USA, with knee pain commonly reported. Multiple therapeutic modalities are traditionally utilized for pain management; however, some patients may have pain refractory to these techniques. Cooled radiofrequency ablation (c-RFA) of the geniculate nerve is a growing and promising therapy offering a potentially long-term solution to chronic knee pain. METHODS: This study assessed the efficacy, average duration of relief, and potential adverse events using a retrospective chart review of 406 procedures. A two-tailed paired t test was used to assess the statistical significance between pre-RFA vs. post-RFA visual analog scale (VAS) pain scores self-reported by patients. An analysis of variance (ANOVA) test was used to evaluate for statistical differences in pre-RFA pain scores and post-RFA pain scores among the categories of age, sex, body mass index (BMI), and diagnosis group. RESULTS: The mean percent in pain improvement calculated was 65.5% with an average duration of relief of 7.20 months. The average pre-RFA pain score on the VAS was 6.26 out of 10 and 2.59 out of 10 post-RFA. The ANOVA post-RFA pain scores demonstrated statistically significant differences among the categories of age and sex. A total of 54 adverse events were reported, including worsening pain, numbness, paresthesia, and knee swelling. CONCLUSION: The study demonstrated that c-RFA can potentially be utilized as an alternative safe therapy for chronic knee pain, providing pain relief with a relatively prolonged duration. Inherent challenges of retrospective studies remain a part of the limitations of this study.

The association of payer type on genicular radiofrequency neurotomy treatment outcomes: Results of a cross-sectional study.

Background: Genicular radiofrequency neurotomy (GRFN) is an effective treatment for a subset of individuals with chronic knee pain. Previous studies demonstrate that Medicare and Medicaid beneficiaries report worse outcomes following various interventional procedures compared with commercially insured patients. Objective: Evaluate the association of payer type on GRFN treatment outcomes. Methods: Consecutive patients who underwent GRFN at a tertiary academic center were contacted for participation. Demographic, clinical, and procedural characteristics were collected from electronic medical records. Outcome data were collected by standardized telephone survey at 6-12 months, 12-24 months and ≥24 months. Treatment success was defined as ≥50% numerical pain rating scale (NPRS) score reduction from baseline. Data were analyzed using descriptive statistics for demographic, clinical, and procedural characteristics. Logistic and Poisson regression analyses were performed to examine the association of variables of interest and pain reduction. Results: One hundred thirty-four patients treated with GRFN (mean 65.6 ± 12.7 years of age, 59.7% female) with a mean follow-up time of 23.3 ± 11.3 months were included. Payer type composition was 48.5% commercial (n = 65), 45.5% Medicare (n = 61), 3.7% Medicaid (n = 5), 1.5% government (n = 2), and 0.8% self-pay (n = 1). Overall, 47.8% of patients (n = 64) reported ≥50% NPRS score reduction after GRFN. After adjusting for age, follow-up duration, Kellgren-Lawrence osteoarthritis grade, baseline opioid use, antidepressant/antianxiety medication use, history of knee replacement, and number of RFN lesions placed, the logistic regression model showed no statically significant association between payer type and treatment outcome (OR = 2.11; 95% CI = 0.87, 5.11; p = 0.098). Discussion/conclusion: In this study, after adjusting for demographic, clinical, and procedural characteristics, we found no association between payer type and treatment success following GRFN. This observation contrasts findings from other interventional studies reporting an association between payer category and treatment success.

The Analgesic Effectiveness of Genicular Nerve-targeted Cooled and Pulsed Radiofrequency Ablation for Osteoarthritis Knee Pain: A Systematic Review and Meta-analysis.

BACKGROUND: Radiofrequency ablation (RFA) is a form of therapy for knee osteoarthritis (OA) pain that has become more popular in recent years. In addition to standard RF approaches, there are cooled and pulsed options. RFA could be used to treat the superolateral, superomedial, and inferomedial branches of the genicular nerves. Pulsed and cooled RF ablation on the genicular nerve to treat knee OA pain, however, has not yet been shown to be effective. OBJECTIVES: We conducted a meta-analysis to assess nonconventional, pulsed or cooled, RFA on the genicular nerve to treat knee OA pain; intended our study to provide useful information in deciding whether to use nonconventional RFA because of its effectiveness. STUDY DESIGN: Meta-analysis study of nonconventional, pulsed or cooled, RFA on the genicular nerve to treat knee OA pain. METHODS: PubMed, Ovid MEDLINE, Scopus, and Cochrane Central were searched for eligible papers. In our literature review, procedures, posttreatment outcomes, follow-up data, and adverse events were compiled and analyzed from the selected studies. The National Heart, Lung, and Blood Institute Quality Assessment tool was used to assess therapeutic relevance and evidence strength. Our meta-analysis analyzed pre- and posttreatment pain and physical function scores. The primary outcome was pain measured with either the Visual Analog Scale  or the Numeric Rating Scale. The secondary outcome was physical function measured with the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score. RESULTS: Our systematic review and meta-analysis includes 11 eligible publications (604 patients). Both cooled and pulsed RFA procedures targeting the genicular nerve resulted in considerable pain reduction at post one, 3, 6, and 12 months (P < 0.005). There was no significant improvement in physical function outcome for the cooled RFA technique in all follow-up visits. There was a significant improvement in physical function outcome for the pulsed RFA technique at the one-month and 3-month follow-up visits. LIMITATIONS: Limitations include that there are a limited number of randomized controlled trials available, the methodology utilized for comparison is based on the change in outcome between baseline and follow-up visits. There are only a few papers that have reported physical function outcomes in complete WOMAC rating data. CONCLUSION: At the 6-month follow-up, both cooled and pulsed RFA targeting the genicular nerve provided significant osteoarthritic pain alleviation. There is no different in pain relief between cooled and pulsed RFA targeting the genicular nerve for treating knee osteoarthritis. There was no significant functional improvement of cooled RFA in all follow-ups, but there was a significant functional improvement of pulsed RFA up to 3-month follow-up. According to our study, knee osteoarthritis pain can be efficiently treated with pulsed and cooled radiofrequency with few adverse effects.

Combined genicular artery embolization and genicular nerve block to treat chronic pain following total knee arthroplasty.

BACKGROUND: Chronic knee pain after total knee arthroplasty (TKA) is a common complication that is difficult to treat. This report aims to highlight the benefit of combining embolotherapy and neurolysis intervention for symptomatic relief of post-TKA pain in a patient with long-standing pain refractory to conservative management. CASE PRESENTATION: A 77-year-old man who had previously undergone left knee arthroplasty has been grappling with worsening knee effusion and debilitating pain, resulting in limited mobility and progressive musculature deconditioning over a 20-year period. Diagnostic arteriography showed marked diffuse periarticular hyperemia around the medial and lateral joint spaces of the left knee, along with capsular distention. The patient initially underwent microsphere embolization to selectively target multiple branches of the genicular arteries, achieving a 50% reduction in pain at the one-month follow-up. Subsequently, the patient underwent image-guided genicular nerve neurolysis, targeting multiple branches of the genicular nerves, which led to further pain reduction (80% compared to the initial presentation or 60% compared to post-embolization) at the one-month follow-up. This improvement facilitated weight-bearing and enabled participation in physical therapy, with sustained pain relief over the 10-month follow-up period. CONCLUSION: The combination of genicular artery embolization and genicular nerve block may be a technically safe and effective option for alleviating chronic pain after total knee arthroplasty.