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

NCT07712419 | Recruiting

• 1 other identifier: MEDIPOL-EC-845-2026
• Study Type: observational
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

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.

Conditions

Knee Osteoarthritis; Chronic Knee Pain

Keywords

Genicular Nerve Block; Knee Osteoarthritis; Ultrasonography; Sonographic Thigh Adjustment Ratio

Outcome Measures

Primary Outcomes (1)

• Treatment Response at 1 Month Following Genicular Nerve Block

  Treatment response will be defined as a ≥50% reduction in Visual Analog Scale (VAS) pain score from baseline at 1 month after ultrasound-guided genicular nerve block. The predictive value of baseline Sonographic Thigh Adjustment Ratio (STAR) for 1-month treatment response will be evaluated.

  1 month

Secondary Outcomes (4)

• Responder Pattern After Genicular Nerve Block

  1 month, and 3 months

• WOMAC Score

  Baseline, 1 month, and 3 months

• Five Times Sit-to-Stand Test

  Baseline, 1 month, and 3 months

• Change in Pain Intensity

  Baseline, 1 month, and 3 months

Study Arms (1)

Patients With Knee Osteoarthritis Undergoing Genicular Nerve Block

Adults with symptomatic Kellgren-Lawrence grade 3-4 knee osteoarthritis undergoing ultrasound-guided genicular nerve block as part of routine clinical care. Participants undergo baseline ultrasonographic assessment of quadriceps muscle thickness, subcutaneous fat thickness, and calculation of the Sonographic Thigh Adjustment Ratio (STAR), followed by clinical follow-up at 1 and 3 months.

Procedure: Ultrasound-Guided Genicular Nerve Block

Interventions

Ultrasound-Guided Genicular Nerve Block PROCEDURE

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.

Patients With Knee Osteoarthritis Undergoing Genicular Nerve Block

Eligibility Criteria

• Age: 45 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Adults with symptomatic bilateral Kellgren-Lawrence grade 3-4 knee osteoarthritis referred from the Department of Physical Medicine and Rehabilitation to the Pain Medicine Clinic for ultrasound-guided genicular nerve block after failure of conservative treatment. Consecutive eligible patients meeting the inclusion criteria will be enrolled prospectively.

You may qualify if:

• 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.

You may not qualify if:

• 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.

Sponsors & Collaborators

• Gaziosmanpasa Research and Education Hospital: lead

Study Sites (1)

University of Health Sciences Gaziosmanpaşa Physical Therapy and Rehabilitation Training and Research Hospital

Istanbul, 34255, Turkey (Türkiye)

RECRUITING

Related Publications (3)

• 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 RESULT

• 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 RESULT

• 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 RESULT

MeSH Terms

Conditions

Osteoarthritis, Knee

Condition Hierarchy (Ancestors)

Osteoarthritis; Arthritis; Joint Diseases; Musculoskeletal Diseases; Rheumatic Diseases

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Target Duration: 3 Months
• Sponsor Type: OTHER GOV
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: July 14, 2026
• First Posted: July 17, 2026
• Study Start: May 15, 2026
• Primary Completion (Estimated): September 1, 2026
• Study Completion (Estimated): November 1, 2026
• Last Updated: July 17, 2026

Record last verified: 2026-07

Locations

TU (1)