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Recruiting NCT07712419

Sonographic Thigh Adjustment Ratio and Subcutaneous Fat Thickness as Predictors of Genicular Nerve Block Response in Knee Osteoarthritis

— Observational Knee Osteoarthritis Chronic Knee Pain

For patients and families

In plain language

An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.

What is being studied
The protocol lists: Ultrasound-Guided Genicular Nerve Block.
Who it may be relevant to
Registry conditions: Knee Osteoarthritis, Chronic Knee Pain. Basic parameters: from 45 years · All.
What needs checking
Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
Where it takes place
Turkey (Türkiye)
Next step
Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →

Unsure about the terms? Read our patient guide →

Official title

Sonographic Thigh Adjustment Ratio and Subcutaneous Fat Thickness as Predictors of Genicular Nerve Block Response in Patients With Knee Osteoarthritis Undergoing Genicular Nerve Block: A Prospective Observational Study

Overview

Knee osteoarthritis (KOA) is a leading cause of chronic pain and disability. Although genicular nerve block (GNB) is an effective treatment for many patients, treatment response varies considerably. Identifying imaging biomarkers that predict clinical response may improve patient selection and optimize treatment outcomes. This prospective observational study aims to evaluate whether the Sonographic Thigh Adjustment Ratio (STAR), calculated as anterior quadriceps muscle thickness divided by body mass index (BMI), and subcutaneous fat thickness are associated with pain relief following genicular nerve block in patients with symptomatic knee osteoarthritis. Ultrasound measurements will be obtained before the procedure, and clinical outcomes will be assessed during follow-up. The primary objective is to determine whether sonographic muscle parameters can predict treatment response after GNB.

Detailed description

Knee osteoarthritis is one of the most common musculoskeletal disorders worldwide and is frequently associated with chronic pain, impaired mobility, and reduced quality of life. Genicular nerve block has become an established minimally invasive treatment for patients with persistent pain despite conservative management. However, substantial variability exists in treatment response, highlighting the need for reliable predictors of clinical success.

Recent studies have suggested that ultrasound-derived muscle measurements may provide objective information regarding muscle quality and sarcopenia. The Sonographic Thigh Adjustment Ratio (STAR), defined as anterior quadriceps muscle thickness normalized to body mass index (BMI), has been proposed as an ultrasound-based indicator of muscle mass. Nevertheless, its potential role in predicting the response to interventional pain procedures has not been investigated.

This prospective observational cohort study will enroll patients with symptomatic knee osteoarthritis who undergo ultrasound-guided genicular nerve block as part of routine clinical care. Before the procedure, ultrasound measurements of anterior quadriceps muscle thickness and subcutaneous fat thickness will be obtained. STAR will be calculated by dividing anterior quadriceps muscle thickness by BMI. Clinical outcomes will be assessed using validated pain and functional outcome measures during follow-up.

The primary objective is to evaluate whether STAR predicts treatment response after genicular nerve block. Secondary objectives include investigating the predictive value of quadriceps muscle thickness and subcutaneous fat thickness individually and exploring their relationship with pain reduction and functional improvement.

Interventions

  • Procedure Ultrasound-Guided Genicular Nerve Block
    Ultrasound-guided genicular nerve block was performed as part of routine clinical care in patients with symptomatic knee osteoarthritis. The superomedial, superolateral, and inferomedial genicular nerves were targeted using a standardized ultrasound-guided technique. A standardized injectate consisting of bupivacaine, dexamethasone, and normal saline was administered to each target nerve. The procedure was performed by an experienced pain physician using the same protocol for all participants.

Primary outcome measures

  • Treatment Response at 1 Month Following Genicular Nerve Block [Time frame: 1 month]
Secondary outcome measures (4)
  • Responder Pattern After Genicular Nerve Block [Time frame: 1 month, and 3 months]
  • WOMAC Score [Time frame: Baseline, 1 month, and 3 months]
  • Five Times Sit-to-Stand Test [Time frame: Baseline, 1 month, and 3 months]
  • Change in Pain Intensity [Time frame: Baseline, 1 month, and 3 months]

Eligibility criteria

Inclusion criteria

  • Age ≥45 years.
  • Symptomatic bilateral knee osteoarthritis with Kellgren-Lawrence grade 3 or 4.
  • Visual Analog Scale (VAS) pain score ≥4 at rest or during movement.
  • Scheduled to undergo first ultrasound-guided genicular nerve block.
  • No intra-articular knee injection within the previous 3 months.
  • Considered unsuitable for or awaiting total knee arthroplasty.
  • Ability to provide written informed consent.

Exclusion criteria

  • Inflammatory arthritis, rheumatoid arthritis, or crystal arthropathy.
  • Previous knee surgery or knee prosthesis.
  • Active local or systemic infection.
  • Anticoagulant therapy or bleeding disorders.
  • Contraindication to corticosteroids (including uncontrolled diabetes mellitus).
  • Allergy to study medications.
  • Neurological disorders causing neuropathic knee pain.
  • Dementia or inability to complete study assessments.
  • Additional interventional procedures or surgery during follow-up.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Observational model
Cohort

Study locations

Turkey (Türkiye) · 1 center
  • University of Health Sciences Gaziosmanpaşa Physical Therapy and Rehabilitation Training a — Istanbul

Publications

  • Vilchez-Cavazos F, Gamboa Alonso AA, Simental-Mendia M, Pena-Martinez VM, Acosta-Olivo CA, Villarreal-Villarreal GA. Genicular Nerve Block for Knee Osteoarthritis: A Systematic Review and Meta-analysis of Randomized Clinical Trials. Clin J Pain. 2024 Oct 1;40(10):618-624. doi: 10.1097/AJP.0000000000001240. PMID 39143682
  • Razaq S, Kara M, Ozcakar L. The Relationship Between Sarcopenic Obesity and Knee Osteoarthritis: The SARCOB Study. Eur J Rheumatol. 2023 Aug 18. doi: 10.5152/eurjrheum.. Online ahead of print. PMID 37594394
  • Kara M, Kaymak B, Ata AM, Ozkal O, Kara O, Baki A, Sengul Aycicek G, Topuz S, Karahan S, Soylu AR, Cakir B, Halil M, Ozcakar L. STAR-Sonographic Thigh Adjustment Ratio: A Golden Formula for the Diagnosis of Sarcopenia. Am J Phys Med Rehabil. 2020 Oct;99(10):902-908. doi: 10.1097/PHM.0000000000001439. PMID 32941253

Identifiers

NCT: NCT07712419 · MEDIPOL-EC-845-2026

Primary sources (government registries)

View this study on ClinicalTrials.gov ↗