Genicular Nerve Block Research Articles

Genicular Nerve Radiofrequency Ablation and Dual Subsartorial Block for Chronic Knee Pain Post Total Knee Replacement: A Case Report

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)
 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.
 Conclusion. Treatment of chronic pain post total knee replacemet was challenging, targeted treatment may ameliorate the pain and prevent long term disability.

Comparison of ultrasound-guided femoral + anterior sciatic nerve block and genicular nerve block for postoperative pain in total knee arthroplasty

Purpose: This study aimed to compare the effectiveness of ultrasound-guided femoral and anterior sciatic (FAS) nerve blocks and genicular (G) nerve blocks as preventive analgesia methods after total knee arthroplasty.
 Materials and Methods: Fifty patients, aged 55–80 years were divided into two groups preoperatively. Patients in the FAS group (n=25) received 20 mL solutions (10 mL 0.5% bupivacaine, 1 mL [4 mg] dexamethasone, and 9 mL saline) in both femoral and sciatic blocks. Patients in the G group (n=25) received 5 mL solutions (2 mL 0.5% bupivacaine, 1 mL [4 mg] dexamethasone, and 2 mL saline) for each nerve. Patients were assessed 24 h postoperatively, and pain scores, time to first analgesic requirement, total analgesic dose, and postoperative complications during the first 24 h were recorded.
 Results: VAS scores at postoperative 0, 1, and 6 h and the total amount of tramadol consumed 24 h were lower in the FAS group than in the G group. There was no requirement for additional analgesia in the first 24 h in the FAS group; however, 9 patients required additional analgesia in the G group. 
 Conclusion: USG FAS nerve blocks were superior to the genicular nerve blocks in TKA. Additionally, the genicular block doesn’t cause motor block. A genicular block can be considered as an alternative with this regard.

Bipolar Radiofrequency Neurotomy of the Genicular Nerves for Chronic Pain Due to Knee Osteoarthritis.

Background: The current treatments for chronic knee osteoarthritis (OA), a disabling and costly healthcare condition in the United States, vary in their level of supporting evidence. Although total knee replacement is one of the best-supported interventions, its associated risks should not be taken lightly, especially in older patients with comorbidities. Genicular nerve block with subsequent genicular nerve radiofrequency neurotomy (GN-RFN) has emerged as a promising intervention for refractory pain in knee OA. Purposes/Questions: We sought to assess the pain and functional outcomes of genicular nerve bipolar radiofrequency neurotomy (B-RFN) for the treatment of chronic pain due to knee OA. Methods: A total of 21 patients who underwent unilateral genicular nerve B-RFN after positive diagnostic genicular nerve block (50% or greater pain relief) treated between July 2018 to December 2018 were included. Pain numeric rating scale (NRS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores were collected at baseline, 3 months, and 6 months post-B-RFN. Changes at each time point were compared to baseline scores using paired sample t tests. Results: At 3 months, 62% of patients had a greater than 50% improvement in NRS scores and 57% of patients had a greater than 50% improvement in WOMAC scores. At 6 months, 81% of patients had a greater than 50% improvement in NRS scores and 67% had a greater than 50% improvement in WOMAC scores. The absolute change in mean NRS (± standard deviation) at 6 months went from 7.5 ± 1.9 to 2.5 ± 1.2. The absolute change in mean WOMAC scores at 6 months went from 46.9 ± 8.0 to 19.0 ± 6.2. Conclusion: Of 21 patients, 14 (67%) saw greater than 50% improvements in both NRS and WOMAC scores at 6 months after genicular nerve B-RFN. Further prospective studies are needed to determine the selection criteria of patients most likely to benefit from this procedure.

Intra-articular corticosteroid injection and genicular nerve block under ultrasound guidance in pain control of knee osteoarthritis

BackgroundChronic knee osteoarthritis (OA) is a frequent disease among the elderly. Intra-articular corticosteroid injection (IACSI) was commonly adopted to alleviate knee OA-related pains. Recently, Genicular nerve block (GNB) has emerged as a new alternative technique. The current study aimed to investigate the efficacy of those two approaches when guided with ultrasound and to determine which one offers better results. This study included 40 patients with painful chronic knee OA (Nine males and 31 females, age ranged from 44 to 65 years) and were randomly assigned to two equal groups. Groups 1 was managed with ultrasound-guided IACSI and group 2 with ultrasound-guided GNB using a mixture of lidocaine and Triamcinolone Acetonide. The baseline mean visual analogue scale (VAS) and Oxford knee score (OKS) for the group 1 were 87.10 and 51.3, while for group 2 were 87.75 and 53.25 respectively. Follow up values were obtained at 2, 4 and 8 weeks using VAS and OKS.ResultsThe VAS score and OKS score were significantly lower in the GNB group and IACSI group at 2, and 4 weeks after the procedure (p < 0.001 for all), then returned near baseline values at 8 weeks. When the two groups were compared according to changes in VAS and OKS from baseline at 2, 4, and 8 weeks, GNB group showed significant alleviation of pain (mean reduction of 58.5, 53.3, and 9.25 points at 2, 4, and 8 weeks versus 44.9, 39.4, and 5.6 points at the IACSI groups, p < 0.001 at 2 and 4 weeks, p < 0.006 at 8 weeks). Similarly at the OKS, the GNB group showed significantly better results (33.50, 28.60, and 8.5 at GNB and 26.45, 20.10, 5.25 at IACSI. p < 0.001 at all periods).ConclusionsBoth GNB and IACSI are effective methods to relieve chronic knee osteoarthritis-related pains. When compared to each other, GNB showed more significant pain relief and functional improvement than IACSI.

Comparison of Genicular Nerve Block in Combination With Adductor Canal Block in Both Primary and Revision Total Knee Arthroplasty: A Retrospective Case Series.

The management of pain in patients undergoing total knee arthroplasty (TKA) for chronic knee osteoarthritis (OA) has remained a challenge for the anesthesiologist regarding regional anesthesia as no single regional technique is adequate with regard to balancing effective analgesia with minimal muscle weakness. Severe postoperative pain following TKA has been shown to negatively impact patient outcomes and mortality. The genicular nerve block has recently been demonstrated to provide effective analgesia to the anterior and posterior knee capsule in recent studies. In this retrospective case series, we compare the efficacy of combined genicular nerve block (GNB) and adductor canal block (ACB) to only ACB in both primary and revision TKA patients. This combined novel approach for TKA patients can be utilized to improve patient pain scores and early ambulation, limiting the use of opioids and early discharge.

Genicular nerve block in rheumatoid arthritis: a randomized clinical trial.

This study highlights the effect of a genicular nerve block (GNB) on pain, function, and inflammation outcome measures in rheumatoid arthritis (RA) knees. A total of sixty-four patients diagnosed with RA using ACR/EULAR 2010 criteria with unilateral persistent knee arthritis were recruited to the study. They were randomly assigned into two groups: group 1 received GNB and group 2 received intra-articular triamcinolone. Both groups were examined by the SOLAR scoring system, visual analog scale (VAS), and Lysholm score at 0, 2, and 12weeks. A semi-quantitative score was used to assess the tenderness and swelling at the same intervals. Function and inflammation improved significantly in group 2 at a 2-week interval as compared to group 1, whereas pain improved in both groups with non-significant differences. After 12weeks, group 1 showed significant improvement as compared with group 2 for the three outcome measures. Neither the disease activity nor the current medication was related to the GNB effect. Disease duration was negatively related to GNB-induced improvement. GNB is a new promising local therapy for RA to control pain, improve function, and alleviate inflammation of the knee joint. Although it has a relatively short-term effect, yet it has outperformed the steroid effect. Key Points • Knee monoarthritis treatment in rheumatoid arthritis is always challenging • GNB has been approved for the treatment of pain in knee osteoarthritis • GNB in this study was able to control active knee arthritis and this effect persisted longer thane intra-articular steroid injection.

Comparison of the Therapeutic Efficacy of TENS vs Ultrasound-guided Genicular Nerve Block in Patients with Knee Osteoarthritis

Comparison of the Therapeutic Efficacy of TENS vs Ultrasound-guided Genicular Nerve Block in Patients with Knee Osteoarthritis

Ultrasound-guided genicular nerves block: an analgesic alternative to local infiltration analgesia for total knee arthroplasty: A noninferiority, matched cohort study.

Standard analgesic strategies for total knee arthroplasty employ local infiltration analgesia. Blockade and radiofrequency ablation of the genicular nerves are effective treatments for patients with chronic pain because of knee osteoarthritis. To test the noninferiority of the analgesic effect of genicular nerves block in comparison with local infiltration analgesia after 24 h of total knee arthroplasty. Prospective cohort study. Perioperative setting. Thirty-five patients scheduled for total knee arthroplasty were prospectively included in the study and compared with 35 patients in a retrospective cohort. Genicular nerve blocks in the prospective cohort were compared with local infiltration analgesia in the retrospective cohort. The pain numeric rating scale and the cumulative opioid consumption in oral morphine equivalents during the first 24 h. We conducted propensity score-matched analyses of patients using acute postoperative pain-related risk covariates. After one-to-one propensity score matching, 21 patients were included in the local infiltration analgesia group and 21 in the genicular nerve block group. The median difference in numeric rating score at rest at 24 h was -0.99 [95% confidence interval (CI), -1.99 to 0.5, P = 0.012] on the unmatched cohort and -1.9 (95% CI, -2 to 0, P = 0.002) on the matched cohort (meeting the noninferiority criteria, Δ=1). The median difference in cumulative opioid consumption was 2.5 mg (95% CI, -13.5 to 2.5, P < 0.001) for the unmatched cohort and 4.99 mg (95% CI, -11.5 to 2.5, P < 0.001) on the matched group (meeting the noninferiority criteria, Δ = 21 mg). Local infiltration analgesia and genicular nerve block are comparable in terms of analgesic results. Therefore, genicular nerves block is an alternative to local infiltration analgesia in patients undergoing total knee arthroplasty. Clinicaltrials.gov identifier: NCT04024319.

COMPARATIVE STUDY BETWEEN INTRA-ARTICULAR CORTICOSTEROID INJECTION AND GENICULAR NERVE BLOCK UNDER ULTRASOUND GUIDANCE IN PAIN CONTROL OF KNEE OSTEOARTHRITIS

Recently, genicular nerve block (GNB) was introduced as a new technique to relieve knee pain in chronic knee osteoarthritis patients. While intra-articular corticosteroid injection (IACSI) used to be a traditional treatment option to relieve knee osteoarthritis related pains. Both techniques have been used. However, whether one is superior to the other remains controversial.Aim of work: This study aims to investigatethe efficacy of ultrasound-guided GNB and IACSI in the management of knee osteoarthritis-related pains and to determine which technique carried better results.Methods:Forty patients with chronic knee osteo-arthritis were randomly treated with either genicular nerve block (GNB) (n = 20) or intra-articular corticosteroid injection (IACSI) (n = 20). Clinical response was assessed using Visual analog scale (VAS), and Oxford Knee Score (OKS) at baseline and 2, 4, and 8 weeks post procedure. Results: The VAS score and OKS score were significantly low in the GNB group and IACSI group at 2, and 4 weeks after the procedure (P < 0.001 for all), then returned near baseline at 8 weeks. When the two groups were compared according to changes in VAS and OKS from baseline at 2, 4, and 8 weeks, GNB group showed significant alleviation of pain (P < 0.001 for 2 and 4 weeks and < 0.006 for 8 weeks) and improvement in function (P < 0.001 for 2, 4 and 8 weeks) compared to IACSI group.

TO COMPARE THE EFFICACY OF GENICULAR NERVE BLOCK AND INJECTION OF HYLAN G-F 20 VERSUS GENICULAR NERVE BLOCK ONLY FOR IMPROVING PAIN AND FUNCTION OF GRADE-II AND GRADE-III OSTEOARTHRITIS KNEE

Introduction: Osteoarthritis (OA) of knee joint is a degenerative joint disease; heterogeneous and progressive in nature. Clinically presented with stiffness, swelling and pain which leads to a decrease in the quality of life. The presence of chronic knee pain has been found to be a strong predictor of future disability and dependency in older adults. Usually managed conservatively but if conservative treatment fails, Total Knee Replacement (TKR) is traditionally considered. This is associated with multiple perioperative morbidities. On the contrary, many patients are not suitable for surgical procedure and some do not want to go for surgical intervention. As many patients are not surgical candidates due to co-morbidities or unwillingness; other treatment options available are being sought for. The genicular nerve block (GNB) reduces pain and improves patient functions by blocking pain transmission of the sensory nerves. Combining this genicular nerve block with viscosupplementation (Injection Hylan G-F 20) appears to play a role and can be tried in patients suffering in grade II and grade III (radiological grading) osteo arthritis. There is paucity of information so as to compare the efcacy of genicular nerve block and injection of Hylan G-F 20 versus genicular nerve block only. Material And Methods: This Parallel group open label randomized controlled trial was done between July, 2018 to December, 2019 (Eighteen months). Patients with knee pain in grade II and III, OA knee attending the PMR OPD in IPGME&amp;R, Kolkata in the specied tenure was considered for the study. The selected patients were allotted by random table. All the procedures were performed by single person. A total number of 60 patients with knee osteoarthritis of grade II and III, who did not respond with conservative management were included. Combined therapy of intra-articular injection of Hylan G-F 20 and genicular nerve block in Group 1 (Genicular Nerve Block and Injection Hylan G-F 20) and Genicular Nerve Block only in Group 2, performed to 30 patients in each arm. The three branches of the genicular nerve [superior lateral (SL), superior medial (SM), and inferior medial (IM) genicular nerves] were selected. Patients were evaluated initially (0 week) and at the 4th and 12th week followed up after intervention using VAS and WOMAC scale. Ultrasound guided genicular nerve block conducted under strict asepsis after proper dressing and draping with the visualization of genicular nerves (upper medial, upper lateral and lower medial quadrant) by musculoskeletal probe of Ultrasound machine (SAMSUNG/ Model PT60A/Musculoskeletal probe 12MHz). Injection Hylan G-F 20 (6 ml) intra-articular injection was given under strict asepsis. Results: 47% patients in group 1 and 67% patients in group 2 were in between 60-69 years. There is female preponderance in both the groups. WOMAC-pain score for dual intervention at 4th week was statistically signicantly lower compared to WOMAC-pain score obtained at any time of observation and any type of intervention. WOMAC- stiffness score for dual intervention at 4th week was statistically signicantly lower compared to WOMAC- stiffness score obtained at any time of observation. WOMAC SCORE: The changes in each intervention group at 0-week, 4th week and 12th week were statistically signicant. Statistically signicant difference of two groups were lost during 4th and 12th weeks observation. VAS: During 4th and 12th weeks observation, statistically signicantly different VAS score was observed among the two interventions; Genicular nerve block with injection consistently had a lower VAS score. This nding imply that Genicular nerve block alone did reduce the pain; however, reduction was greater in case of Genicular nerve block with Injection Hylan G-F 20 in both 4th and 12th week of observation. Conclusion: Genicular Nerve Block with injection HYLAN GF 20 (Combined Therapy Group) and Genicular Nerve Block alone are effective method of pain reduction in osteoarthritis knee. Combined Therapy doesn't have an added advantage as per WOMAC Score. But Combined therapy has a denite advantage over Genicular Nerve Block alone as per VAS Score.

Comparison of efficacy between the genicular nerve block and the popliteal artery and the capsule of the posterior knee (IPACK) block for total knee replacement surgery: A prospective randomized controlled study.

The aim of this study was to compare the efficacy of popliteal artery and the capsule of the posterior knee (IPACK) block and genicular nerve block on postoperative pain scores, the need for rescue analgesics, range of motion (ROM), walking distance, and perioperative monitorization variables in patients undergoing total knee replacement (TKR) surgery. Sixty American Society of Anesthesiologists (ASA) physical status I-III patients were enrolled in this study and then were randomly assigned into three groups: the IPACK block group (17 female, 3 male; mean age=67.5±1.4 years), genicular nerve block (16 female, 4 male; mean age=68±1.76 years), and the control group (13 female, 7 male; mean age=63±1.67years). All the patients underwent TKR under spinal anesthesia. The visual analog scale (VAS) score, mobility, pre- and intra-operative monitorization of systolic and diastolic holding area, non-invasive blood pressure, heart rate, and SPO 2 were compared between the groups. Patients in the IPACK and genicular block groups had a significantly lower visual analogous scale (VAS) at postoperative 4 hours (p<0.01), 8h (p<0.01), 12h (p<0.01), and 24h (p<0.05). VAS score was significantly lower in the genicular block group at the postoperative 4h (5.5±0.55) and 8h (5.0±0.53) in the mobile state compared to the IPACK (8.0±0.47 and 8.0±0.43, respectively) and the control group (9.5±0.20; 10±0.28, respectively) (p< 0.01). The use of patient-controlled-analgesia (PCA) devices and button push count for analgesics demand were significantly lower in the genicular block group on the immediate postoperative period (p<0.01 at the postoperative 0 to 4 h). The total consumption of morphine equivalents on the postoperative day 0 was significantly lower in the genicular block group (p<0.01, and p<0.001 for IPACK and control groups, respectively). The degree of flexion was significantly higher in the genicular block group at the postoperative 12h compared to the IPACK and the control group (p<0.001). The length of hospital stay was significantly lower in the genicular block group compared to the IPACK and the control group (p<0.05 for both variables). IPACK and genicular blocks both are effective in improving patient comfort during and after TKR surgery and reducing the potential need for systemic analgesic and opioids. The genicular block seems to be a promising technique that can offer improved pain management in the immediate and early postoperative period without adverse effects on systemic and motor variables.

Should a Coexisting or Suspected Diagnosis of Fibromyalgia Affect the Decision to Perform Diagnostic Blocks for Patients with Chronic Noncancer Pain — Results from an Observational Research Study

Diagnostic injections (blocks) are a valuable tool in the management of chronic noncancer pain. By precise blockade of specific neural structures and observation of pain responses, pain mechanisms can be accurately defined. With such information, therapeutic procedures targeting neural structures are possible. Fibromyalgia is a disorder of pain processing with characteristic symptoms. The 2010 American College of Rheumatologists fibromyalgia diagnostic criteria evaluates these symptoms in a scoring system, allowing more objectivity in the diagnosis. We hypothesize that patients with fibromyalgia phenotype fulfilling the 2010 American College of Rheumatologists criteria may respond to diagnostic blocks differently when compared to patients without fibromyalgia phenotype. This study was designed to establish whether diagnosis or suspected diagnosis of fibromyalgia should influence the decision to perform diagnostic blocks for chronic non-cancer pain. A prospective observational research study was performed at our institution. IRAS project ID: 231514. Tertiary pain clinic in the UK. Patients were selected to receive diagnostic block by usual clinical assessment after which they were asked to consent to take part in the study. All participating patients completed the 2010 American College of Rheumatologists fibromyalgia diagnostic questionnaire prior to the diagnostic block. Patients were divided into 2 groups A and B based on the outcome of block - primary outcome. Group A experienced a 70% or greater improvement in pain severity following the block for the anticipated duration of action of the local anesthetic, Group B experienced a less than 70% reduction in pain. Statistical analysis between groups A and B was conducted by comparing categorical data, described as percentages, with the chi squared test. Ordinal variables such as Widespread pain index and Symptom severity score are presented as median and analyzed with Mann-Whitney test. Seventy-seven patients were included in the study. Two patients were lost to follow-up. Of the 75 remaining patients, 44 received lumbar medial branch blocks, 19 genicular nerve blocks, 3 blocks to nerves supplying the sacroiliac joint, one suprascapular nerve block, and 6 cervical and 2 thoracic medial branch blocks. Group A contained 38 patients and group B contained 37 patients. There was no statistically significant difference in the prevalence of fibromyalgia screening questionnaire positive patients between groups A (13 out of 38 patients) and B (13 out of 37 patients), P = 0.93. There was no statistically significant difference in the prevalence of fibromyalgia screening questionnaire positive patients in subgroups undergoing the same type of diagnostic block (spinal pain and knee pain). Selection of patients prior to inclusion in the study may introduce bias. Patients were selected by individual treating clinicians using usual clinical practice; however, the exact selection criteria were not standardized. We conclude that after physician selection, the presence of fibromyalgia phenotype does not influence the outcome from diagnostic block. It is likely therefore that fibromyalgia phenotype should not influence the decision to perform diagnostic blocks if indicated based on assessment by an experienced pain physician.

Revisiting the Genicular Nerve Block: An Up-to-Date Guide Utilizing Ultrasound Guidance and Peripheral Nerve Stimulation – Anatomy Description and Technique Standardization

Over the last decade, several authors have reported that percutaneous peripheral nerve stimulation (PNS) can be used to assist in verifying the position of the procedure needle tip in relation to nerve structures, and that the combined technique using both ultrasound (US) guidance and PNS may serve as a reliable method for confirmation of the correct position of the procedure needle tip. It has also been reported that, when combined with US guidance, PNS may increase the success rate of pain management interventions. The aim of this technical report was to standardize an effective and easy to learn illustrated step-by-step technical approach to nerve identification during US-guided genicular nerve blocks, using percutaneous PNS as a verification instrument for procedure needle tip location. This technical protocol was developed based on the results of the authors' most recent cadaveric study on the innervation of the knee joint capsule. The technique was developed and tested by 4 different interventionists with different levels of expertise in US-guided procedures. The cadaveric study of the knee joint capsule innervation was performed at the laboratory of the Division of Anatomy of one institution. The technical protocol using US and PNS was later developed at the medical simulation center of a different institution. A team of anatomists from a division of anatomy of one institution performed the cadaveric study on the innervation of the knee joint capsule. A team of physicians then developed the step-by-step approach to this technical protocol at the medical simulation center of a different institution. Finally, the illustrated step-by-step approach was tested by 4 different interventionists with different levels of expertise in US-guided procedures (1 beginner-level user; 1 intermediate-level user; 2 expert-level users), using a portable percutaneous PNS and 2 different US transducers at 2 different institutions. This technical protocol was successfully developed based on the results of the cadaveric study on the innervation of the knee joint capsule. Additionally, it was later successfully tested by interventionists with various levels of expertise utilizing different US equipment at separate institutions. By combining US and nerve stimulation, this protocol requires the availability of both US equipment and necessary equipment for nerve stimulation that must all be made available in the sterile field. Another potential disadvantage is that nerve stimulation controls and the US image screen are generally located on 2 separate display panels, which could cause difficulty with visualization and simultaneous calibration for 2 individual devices. Our illustrated step-by-step technical protocol can be effectively and safely utilized as a reliable method of training, by which physicians with little to moderate US experience can improve their skills in accurately identifying the genicular nerves while performing US-guided examinations with the intent of executing a peripheral nerve block.

Is Cooled Radiofrequency Genicular Nerve Block and Ablation a Viable Option for the Treatment of Knee Osteoarthritis?

BackgroundThe purpose of this study was to determine demographic and psychosocial factors that influence the effectiveness of cooled radiofrequency genicular nerve ablation (C-RFA) and block in patients with chronic knee pain secondary to osteoarthritis (OA).MethodsA retrospective review was completed including patients with knee OA who underwent genicular nerve ablation or block or both. Patient information collected included opioid use, psychological comorbidities, smoking history, body mass index, and medical comorbidities. Success was defined using the Osteoarthritis Research Society International criterion of greater than or equal to 50% reported pain relief from the procedure. Patients without a diagnosis of knee OA and patients with ipsilateral total knee arthroplasty were excluded. Patient factors were compared between (1) those that did or did not respond to the initial block and (2) those that did or did not respond to C-RFA.ResultsOf the 176 subjects that underwent genicular nerve block, 31.8% failed to respond to the procedure. Subjects that failed the initial block were significantly more likely to have psychological comorbidities, smoking history, and diabetes. Of the subjects that proceeded to genicular nerve ablation, 53.7% reported less than 50% pain relief, and 46.3% reported pain relief greater than or equal to 50% at the first follow-up visit. While the presence of psychological comorbidities, smoking, and diabetes were associated with first-stage block failures, these patient factors were not associated with second-stage ablation failures.ConclusionsC-RFA may be an effective adjunct therapy as part of a multimodal pain regimen; however, individual patient characteristics must be considered.

Can the addition of ultrasound-guided genicular nerve block using 5% dextrose water augment the effect of autologous platelet rich plasma in treating elderly patients with knee osteoarthritis?

BackgroundTo investigate whether the addition of injecting 5% dextrose water to the genicular nerves can augment the effect of platelet rich plasma (PRP) injections in treating elderly patients with moderate degree of knee osteoarthritis (OA). MethodsForty-six elderly patients with grade 3 on the Kellgren and Lawrence knee OA grading system were divided into control and genicular nerve block groups. Both groups received 4 milliliters (mL) of PRP injected into the knee joint and 2 mL of PRP to the pes anserinus complex. In the nerve block group, 2 mL of 5% dextrose water was also injected to each genicular nerve. In the control group, normal saline was used to inject the genicular nerves. Proteomic technique of 2-dimensional electrophoresis was used to detect the changes in synovial fluid (SF) protein concentrations. Lequesne Functional Index was used to evaluate knee functional status. ResultsAfter 3 monthly PRP injections, concentrations of SF total protein, and proteins associated with inflammation decreased. Protein concentrations associated with chelation increased. In the nerve block group, improvements in pain and in the functional status of the knee joint lasted up to a period of 6 months. At 1 month and 3 months after the injections, Lequesne Functional Index was less than 7 (a value of 7 or higher indicates knee OA). ConclusionThe concept of combining 5% dextrose water injection to the genicular nerves, and PRP injection into the knee joint and to the pes anserinus complex can be a feasible non-operative conservative treatment option for elderly patients with knee OA.

175. Discrepancy in patient-reported pain using the numeric pain scale and a percentage change to quantify treatment effectiveness after pain injections

BACKGROUND CONTEXT The Numeric Pain Rating Scale (NRPS) may not match with patient-reported percentage pain reduction (PRPPP) at 1 to 4 weeks follow-up, as these patients may be reporting a higher estimated percentage improvement compared to the value calculated from their pain scores PURPOSE The objective of this study was to calculate patients’ pain level prior to and after various fluoroscopic injections using the NRPS. The calculated percent change was then compared to a patient-reported percent change. Our hypothesis was that there is a statistically significant difference in calculated NRPS vs patient-reported percentage change. The discrepancy between calculated percent change compared to the patient reported percent change was studied since accurately assessing patient reported pain impacts clinical management of patients with chronic musculoskeletal pain STUDY DESIGN/SETTING This is a retrospective study using patient reported pre- and postinjection NRPS value were used to calculate a percent change in overall pain ([pre-post)/post] x 100). The calculated percent change was rounded to the nearest degree. This calculated percent change in pain was compared to the patient reported percent change (calculated % - reported %). An overall average change in calculated minus reported percent change was obtained for all the injections. A t-test was also performed to determine if there was a significant difference between the calculated percent change and the reported percent change. PATIENT SAMPLE A total of 135 patients were included. OUTCOME MEASURES The patient reported pre- and postinjection NRPS value were used to calculate a percent change in overall pain ([pre-post)/post] x 100). This calculated percent change in pain was compared to the patient reported percent change (calculated % - reported %). METHODS A total of 135 patients who underwent spinal corticosteroid injections under fluoroscopic-guidance between 2015 and 2017 were retrospectively reviewed. The patient reported pre- and postinjection NRPS value were used to calculate a percent change in overall pain ([pre-post)/post] x 100). This calculated percent change in pain was compared to the patient reported percent change (calculated % - reported %). An overall average change in calculated minus reported percent change was obtained for all the injections. Univariate analysis was utilized to compare the calculated percent change and the reported percent change. RESULTS Data from 135 patient charts was analyzed with a total of 144 injections. This study included 36 males and 99 females. The average patient age was 63.0 years. A total of 42 patients had a BMI >30 and 7 patients had a prior surgical history in the same joint which was injected. Various injections included sacroiliac joint (SI J, n=15), medial branch blocks (MBB, n=21), lumbar transforaminal epidural steroid injections (LTFESI, n=65), lumbar and cervical epidural steroid injections (LESI and CESI, n=25), radiofrequency ablations (RFA), genicular nerve block of the knee, and various shoulder joint injections. The average difference in calculated percent change vs the patient-reported percent change in pain prior to and after the injections was -18.37% (p CONCLUSIONS Effective management of chronic musculoskeletal pain is important due to its physical, social, and financial burden on patients and the healthcare system. Management of chronic pain is heavily impacted by the meaningful use of various patient reported outcome measures. Health insurance companies use variable percent change in pain level to determine effectiveness of treatment. Our data reflects the existence of a statistically significant difference between calculated percent change in pain using the NRPS as compared to patient reported percent change. Based on this analysis it may be valuable to use other functional and psychosocial outcome measures for chronic pain management. Further studies are needed to assess the combined use of the different outcome measures. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Comparing the effectiveness of ultrasound guided versus blind genicular nerve block on pain, muscle strength with isokinetic device, physical function and quality of life in chronic knee osteoarthritis: a prospective randomized controlled study.

BackgroundThe genicular nerve block (GNB) is demonstrated from several reports to alleviate pain and improve knee functionality in patients with chronic knee osteoarthritis (OA). Ultrasound (US)-guided GNB has been the most used imaging method. This study aimed to compare the effectiveness of US-guided versus blind GNB in the treatment of knee OA.MethodsThis prospective, randomized clinical trial included patients with knee OA based on American College of Rheumatology diagnostic criteria. The patients were evaluated for clinical and dynamometer parameters at the baseline, 4 weeks after treatment, and 12 weeks after treatment. The patients underwent blind injection or US-guided injection.ResultsWhen compared with the baseline, both groups showed significant improvement in pain, physical function, and quality of life parameters. Significant differences were observed between the groups for clinical parameters (30-second chair stand test, 6-minute walk test) in favor of the US-guided group. On the other hand, blind injection was more significantly effective on some parameters of the Nottingham Health Profile. There wasn’t any significant improvement in isokinetic muscle strength for either group.ConclusionsThis study demonstrated that both US-guided and blind GNB, in the treatment of knee OA, were effective in reducing symptoms and improving physical function. GNB wasn’t an effective treatment for isokinetic muscle function. US-guided injections may yield more effective clinical results than blind injections.

Genicular nerve radiofrequency ablation as an alternative to total knee arthroplasty in patients being followed in a non-operative multidisciplinary knee osteoarthritis clinic

Purpose: The purpose of our study was twofold. First, to evaluate the efficacy of Genicular Nerve Block (GNB) and Radiofrequency Ablation (RFA) in non-surgical candidates being followed in a multidisciplinary non-operative knee Osteoarthritis clinic. Second, to identify osteoarthritis functional measures and patient factors predicting treatment outcomes from these procedures. This study explores a multidisciplinary approach to the management of knee OA, where patients receive instruction from physical therapy, nutrition, and medical intervention all during the same visit in our multidisciplinary knee OA clinic.

Periarticular needle-based therapies can cause periprosthetic knee infections

Periarticular needle-based therapies such as dry needling, acupuncture, and genicular nerve radiofrequency ablation are becoming more popular for treatment of knee osteoarthritis. These therapies are also being used after total knee arthroplasty for persistent postoperative pain. Although limited published evidence exists for the risk of periprosthetic joint infection after these procedures, we describe one case of periprosthetic joint infection developing shortly after dry needling and another case developing shortly after genicular nerve blocks. We present details of these 2 cases along with a review of the literature regarding the use of periarticular needle-based therapies after total knee arthroplasty.

Procedural Treatments for Knee Osteoarthritis: A Review of Current Injectable Therapies

Knee osteoarthritis is a common painful degenerative condition affecting the aging Canadian population. In addition to pain and disability, osteoarthritis is associated with depression, comorbid conditions such as diabetes, and increased caregiver burden. It is predicted to cost the Canadian healthcare system $7.6 billion dollars by 2031. Despite its high cost and prevalence, controversy persists in the medical community regarding optimal therapies to treat knee osteoarthritis. A variety of medications like nonsteroidal anti-inflammatories and opioids can cause severe side effects with limited benefits. Total knee arthroplasty, although a definitive management, comes with risk such as postoperative infections, revisions, and chronic pain. Newer injectable therapies are gaining attention as alternatives to medications because of a safer side effect profile and are much less invasive than a joint replacement. Platelet-rich plasma is beginning to replace the more common injectable therapies of intra-articular corticosteroids and hyaluronic acid, but larger trials are needed to confirm this effect. Small studies have examined prolotherapy and stem cell therapy and demonstrate some benefits. Trials involving genicular nerve block procedures have been successful. As treatments evolve, injectable therapies may offer a safe and effective pathway for patients suffering from knee osteoarthritis.