Effects of Genicular Nerve Block in Knee Osteoarthritis

Study Overview
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Brief Summary
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Genicular nerve block is a safe and effective therapeutic procedure for intractable pain associated with chronic knee osteoarthritis (OA). There is increasing support for the neuropathic component to the knee OA pain. Investigators proposed that targeting treatment to the underlying pain mechanism can improve pain management in knee OA. There is a debate on injectable solutions used in nerve blocks. Investigators aimed to investigate the efficacy of genicular nerve block and to determine which solution should be appropriate for patients with knee osteoarthritis who have neuropathic or nociceptive pain.

Detailed Description
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The patients who participated in this study were selected from outpatients who attended our hospital for knee pain. These 90 patients were who matched the following criteria. All patients had knee pain for more than 3 months. The ultrasound-guided genicular nerve block was performed at the site of the superior lateral, the superior medial, and the inferior medial genicular nerves. Color Doppler was used to identify the arterial structures which serve as landmarks for the corresponding nerves. This method was used to inject a total of 6 mL of lidocaine or 6 mL dextrose or 6 mL saline at 3 separate target sites: the superior lateral, superior medial, and inferior medial genicular nerves. Pain was evaluated with Analog Analogue Scale (VAS), daily living activities with Western Ontario and McMaster Universities Arthritis Index (WOMAC), maximum distance walked with Lequesne Score, and neuropathic pain was evaluated with painDETECT inquiry form. Outcome measures were assessed at baseline and at 1st, 4th weeks, and 3rd months after the procedure.

Official Title
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Effects of Genicular Nerve Block for Patients With Knee Osteoarthritis Who Have Neuropathic or Nociceptive Pain: A Double-Blind, Randomized Controlled Trial

Conditions
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Knee Osteoarthritis

Intervention / Treatment
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* Drug: Genicular nerve block with lidocaine
* Drug: Genicular nerve block with saline
* Drug: Genicular nerve block with dextrose


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: knee pain for more than 3 month. radiological tibiofemoral OA (Kellgren-Lawrence grade 2-4 ) Exclusion Criteria: acute knee pain, prior knee surgery, other connective tissue diseases that affected the knee, serious neurological or psychiatric disorders, steroid or hyaluronic acid injection therapy during the previous 3 months, sciatic pain, patients with polyneuropathy, anticoagulant medication use, pacemaker use, prior electroacupuncture treatment and physical treatment.

Ages Eligible for Study
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Minimum Age: 50 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Genicular nerve block with lidocaine<br>The ultrasound-guided genicular nerve block was performed at the site of the superior lateral, the superior medial, and the inferior medial genicular nerves. Color Doppler was used to identify the arterial structures which serve as landmarks for the corresponding nerves.10 cm 21 G insulated block needle was inserted and aligned with the ultrasound scanning plane. Once satisfactory position of the needle is confirmed, 6 mL of a solution containing 6 mL of 2% lidocaine or 6 mL dextrose or 6 mL saline was slowly injected. Spread of local anesthetic was documented adjacent to the target nerve. This procedure was performed at the site of the three genicular nerves Interventions: Drug: 6 mL 2% lidocaine Procedure: Genicular nerve block | Drug: Genicular nerve block with lidocaine<br>* The color doppler ultrasound-guided genicular nerve block at the site of the superior lateral, the superior medial, and the inferior medial genicular nerves.<br>|
| Placebo Comparator: Genicular nerve block with saline<br>The ultrasound-guided genicular nerve block was performed at the site of the superior lateral, the superior medial, and the inferior medial genicular nerves. Color Doppler was used to identify the arterial structures which serve as landmarks for the corresponding nerves. 10 cm 21 G insulated block needle was inserted and aligned with the ultrasound scanning plane. Once satisfactory position of the needle time is confirmed, 5 mL of a saline was slowly injected. Spread of local anesthetic was documented adjacent to the target nerve. This procedure was performed at the site of the three genicular nerves. Interventions:Drug: Saline Procedure: Genicular nerve block | Drug: Genicular nerve block with saline<br>* The color doppler ultrasound-guided genicular nerve block at the site of the superior lateral, the superior medial, and the inferior medial genicular nerves.<br>|
| Placebo Comparator: Genicular nerve block with dextrose<br>The ultrasound-guided genicular nerve block was performed at the site of the superior lateral, the superior medial, and the inferior medial genicular nerves. Color Doppler was used to identify the arterial structures which serve as landmarks for the corresponding nerves. 10 cm 21 G insulated block needle was inserted and aligned with the ultrasound scanning plane. Once satisfactory position of the needle time is confirmed, 5 mL of a dextrose was slowly injected. Spread of local anesthetic was documented adjacent to the target nerve. This procedure was performed at the site of the three genicular nerves. Interventions:Drug: Dextrose Procedure: Genicular nerve block | Drug: Genicular nerve block with dextrose<br>* The color doppler ultrasound-guided genicular nerve block at the site of the superior lateral, the superior medial, and the inferior medial genicular nerves.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Efficacy of genicular nerve block on neuropathic pain reduction in knee osteoarthritis | Neuropathic pain reduction is measured by painDETECT questionnaire (PD-Q) which consists of 9 items that evaluate pain quality, pattern and radiation. Possible scores range from -1 to 38, with higher scores indicating more neuropathic-like symptoms. Clinical assessments:score ≤12: unlikely neuropathic pain; score 13-18: possibly neuropathic pain, and score ≥19:likely neuropathic pain. | 3 months | 
| Efficacy of genicular nerve block on nociceptive pain reduction in knee osteoarthritis. | Nociceptive pain reduction is measured by Visual analogue scales (VAS). The score is determined by measuring the distance (mm) on the 10-cm line between the no pain anchor and the patient's mark, providing a range of scores from 0-100. A higher score indicates greater pain intensity. Pain intensity as none, mild, moderate, or severe, the following cut points on the pain VAS have been recommended: no pain (0-4 mm), mild pain (5-44 mm), moderate pain (45-74 mm), and severe pain (75- 100 mm). | 3 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Efficacy of genicular nerve block on physical function in knee osteoarthritis. | Physical functional disability is measured by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). The WOMAC index is a self-administered health questionnaire specifically designed for patients with osteoarthritis of the hip or knee. It consists of 24 multiple-choice items grouped into 3 categories: WOMAC pain, WOMAC stiffness, and WOMAC physical function. The questions are ranked on a 5-point Likert scale (1 point, best result; 5 points, worst result), and the scores are added up for each category. The WOMAC scores from 1 (best) to 5 (worst) points to a system of 0 (worst) to 100 (best) points. | 6 months | 
| Efficacy of genicular nerve block on walking distance in knee osteoarthritis. | Walking distance with or without walking aids is measured by Lequesne algofunctional index.The Lequesne OA index is a 11-question interview format questionnaire with three sections about pain or discomfort, maximum distance walked and possible necessity of crutches and activities of daily living . The Lequesne OA index is scored as the sum of all questions ranging from 0 to 24. Lower score indicates less dysfunction where 0 = no handicap, 1-4 = mild handicap, 5-7 = moderate handicap, 8-10 = severe handicap, 11-13 = very severe handicap, and ≥14 = extremely severe handicap. | 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Neuropathic Pain, Nerve block, Knee osteoarthritis