Association of Subcutaneous Fat Index, Paraspinal Muscle Characteristics, and Facet Morphology With Lumbar Facet Joint Degeneration

September 30, 2026 updated by: Marmara University

Subkutan Yağ İndeksi, Paraspinal Kas Özellikleri ve Faset Morfolojisinin Lomber Faset Eklem Dejenerasyonu Ile İlişkisi: Disk Dejenerasyonunun Olası Aracılık Rolü

This prospective observational study aims to investigate the association between subcutaneous fat index, paraspinal muscle characteristics, facet morphology, and lumbar facet joint degeneration in adults with chronic low back pain. The study will use lumbar magnetic resonance imaging (MRI) obtained as part of routine clinical care. The study will evaluate whether subcutaneous fat index is associated with moderate-to-severe lumbar facet joint degeneration and will also examine the relationships of disc degeneration, facet morphology, paraspinal muscle characteristics, and pain severity with facet joint degeneration.

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Detailed Description

This is a prospective, non-interventional observational clinical study conducted in patients with chronic low back pain. Participants will be adults aged 18 to 75 years who present to the Algology outpatient clinic of Marmara University Pendik Training and Research Hospital and who have a clinical indication for lumbar MRI as part of routine patient care, independent of study participation.

No additional MRI examinations, radiation exposure, medication administration, injections, or invasive procedures will be performed for research purposes. Participation in the study will not alter the patients' routine diagnostic, treatment, or follow-up procedures.

Demographic and clinical characteristics, including age, sex, height, weight, body mass index, smoking status, diabetes mellitus, hypertension, duration and severity of low back pain, and the presence of leg or radicular pain, will be recorded. Pain severity will be assessed using the Numeric Rating Scale.

Lumbar MRI images obtained during routine clinical care will be evaluated for subcutaneous fat index, intervertebral disc degeneration, facet joint degeneration, facet joint angle and tropism, paraspinal muscle cross-sectional area and fat infiltration, and Modic changes. Subcutaneous fat index will be measured at the L1-L2 level. Intervertebral disc degeneration will be assessed using the Pfirrmann classification, while facet joint degeneration will be assessed using the Weishaupt classification. Facet tropism will be calculated as the absolute difference between the right and left facet joint angles. Paraspinal muscle measurements will be performed at the L3-L4, L4-L5, and L5-S1 levels for the multifidus and erector spinae muscles.

The primary objective is to evaluate the association between subcutaneous fat index and moderate-to-severe lumbar facet joint degeneration. Secondary objectives include evaluating the relationships between subcutaneous fat index and total disc degeneration, disc degeneration and facet joint degeneration, facet morphology and facet joint degeneration, paraspinal muscle characteristics and disc or facet joint degeneration, and subcutaneous fat index and pain severity. An exploratory mediation analysis will also assess the potential mediating role of disc degeneration in the relationship between subcutaneous fat index and facet joint degeneration.

Imaging assessments will be performed by an evaluator blinded to pain severity, body mass index, and other clinical findings. Inter-rater or intra-rater reliability will be assessed in a randomly selected subset of approximately 20% of the study sample.

Study Type

Observational

Enrollment (Estimated)

300

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

  • Turkey (Türkiye)
    • Istanbul
      • Istanbul, Istanbul, Turkey (Türkiye), 34890
        • Recruiting
        • Marmara University Pendik Training and Research Hospital
        • Contact:
        • Principal Investigator:
          • Osman Hakan Gündüz, Prof.Dr.

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 75 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Sampling Method

Non-Probability Sample

Study Population

Adults aged 18-75 years with chronic low back pain lasting at least 3 months who present to the Algology outpatient clinic of Marmara University Faculty of Medicine Pendik Training and Research Hospital and have a lumbar MRI clinically indicated as part of routine patient management independently of the study. Routine lumbar MRI images and demographic and clinical characteristics will be evaluated for associations between subcutaneous fat index, intervertebral disc degeneration, facet joint degeneration, facet morphology, and paraspinal muscle characteristics.

Description

Inclusion Criteria:

-

Inclusion Criteria:

  1. Age 18-75 years.
  2. Low back pain lasting for at least 3 months.
  3. Evaluation at the Algology outpatient clinic.
  4. Lumbar MRI has been clinically indicated as part of routine patient management independently of the study.
  5. Lumbar MRI images including sagittal T1-weighted, sagittal T2-weighted, and axial T2-weighted images covering the L1-L2 through L5-S1 levels.
  6. Height and body weight can be measured.
  7. Low back pain severity can be assessed using the Numeric Rating Scale (NRS).
  8. Sufficient cognitive and linguistic capacity to complete the Oswestry Disability Index.
  9. Ability to understand the study and provide informed consent.
  10. Written informed consent to participate in the study.

Exclusion Criteria:

  1. Previous lumbar spine surgery or lumbar fusion.
  2. Acute vertebral fracture or significant lumbar trauma.
  3. Spinal malignancy or vertebral metastasis.
  4. Spondylodiscitis or other spinal infections.
  5. Inflammatory spondyloarthritis.
  6. Advanced lumbar scoliosis.
  7. Severe congenital lumbar vertebral anomaly.
  8. Anatomic variation preventing reliable identification of vertebral levels.
  9. Pregnancy.
  10. Inability to complete the MRI examination.
  11. MRI images inadequate for assessment of subcutaneous fat, intervertebral discs, facet joints, or paraspinal muscles.
  12. Missing clinical data or required outcome measures.
  13. Failure to provide written informed consent.

Exclusion Criteria:

-

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Observational Models: COHORT
  • Time Perspectives: PROSPECTIVE

Cohorts and Interventions

Group / Cohort
Intervention / Treatment
Chronic Low Back Pain Cohort

Participants with chronic low back pain who meet the eligibility criteria and undergo lumbar MRI as part of routine clinical care will be included in this observational cohort. MRI findings and demographic and clinical characteristics will be evaluated to investigate the associations between subcutaneous fat index, paraspinal muscle characteristics, facet morphology, intervertebral disc degeneration, and lumbar facet joint degeneration.
Diagnostic test: Lumbar Magnetic Resonance Imaging (MRI)

Lumbar MRI images obtained as part of routine clinical care will be evaluated for study purposes. No additional MRI examination or radiation exposure will be performed because of study participation. MRI findings will be assessed for subcutaneous fat index, intervertebral disc degeneration, facet joint degeneration, facet morphology, and paraspinal muscle characteristics.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Association between subcutaneous fat index and moderate-to-severe lumbar facet joint degeneration
Time Frame: At baseline

Moderate-to-severe lumbar facet joint degeneration will be defined as Weishaupt Grade ≥2 in the right or left facet joint at any lumbar level from L1-L2 to L5-S1. The association with subcutaneous fat index measured on lumbar MRI will be evaluated.
At baseline

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Association between subcutaneous fat index and total Pfirrmann score
Time Frame: At baseline

The association between subcutaneous fat index and total Pfirrmann score for lumbar intervertebral disc degeneration will be evaluated.
At baseline
Association between intervertebral disc degeneration and facet joint degeneration
Time Frame: At baseline

The association between intervertebral disc degeneration and lumbar facet joint degeneration will be evaluated using Pfirrmann and Weishaupt classifications.
At baseline
Association between facet angle, facet tropism, and facet joint degeneration
Time Frame: At baseline

The associations between facet angle, facet tropism, and lumbar facet joint degeneration will be evaluated.
At baseline
Association between paraspinal muscle characteristics and intervertebral disc and facet joint degeneration
Time Frame: At baseline

The associations between paraspinal muscle characteristics, including total cross-sectional area, functional cross-sectional area, and fat infiltration, and intervertebral disc and lumbar facet joint degeneration will be evaluated.
At baseline
Association between subcutaneous fat index and low back pain severity
Time Frame: At baseline

The association between subcutaneous fat index and low back pain severity will be evaluated using the Numeric Rating Scale (NRS).
At baseline
Exploratory mediation analysis of intervertebral disc degeneration in the association between subcutaneous fat index and facet joint degeneration
Time Frame: At baseline

The potential statistical mediation role of intervertebral disc degeneration in the association between subcutaneous fat index and lumbar facet joint degeneration will be evaluated as an exploratory analysis.
At baseline

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Marmara University

Investigators

  • Principal Investigator: OSMAN H GÜNDÜZ, Marmara University

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

September 1, 2026

Primary Completion (Estimated)

June 1, 2027

Study Completion (Estimated)

June 1, 2027

Study Registration Dates

First Submitted

September 30, 2026

First Submitted That Met QC Criteria

September 30, 2026

First Posted (Actual)

October 6, 2026

Study Record Updates

Last Update Posted (Actual)

October 6, 2026

Last Update Submitted That Met QC Criteria

September 30, 2026

Last Verified

September 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 09.2026.26-0770

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

Individual participant data will not be shared with other researchers because no plan for individual participant data sharing has been established for this study.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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