Fear-Avoidance Beliefs and Physical Function in Patients With Lumbar Disc Herniation (FAB-LDH)

August 10, 2026 updated by: Mohammed Issa, Istinye University

The Relationship Between Fear-Avoidance Beliefs and Trunk Muscle Endurance, Balance, and Functional Impairment in Patients With Lumbar Disc Herniation

Lumbar disc herniation is one of the most common causes of low back pain and is associated with substantial functional limitations and reduced quality of life, particularly among working-age individuals. Displacement of disc material toward the spinal canal may result in mechanical compression and inflammation of the nerve roots, leading to pain, restricted movement, and reduced functional performance.

The course of low back pain cannot be explained solely by biomechanical and anatomical factors. Psychosocial factors also play an important role in symptom persistence and functional outcomes. Within this context, the fear-avoidance model provides an important theoretical framework, suggesting that individuals may develop fear of movement and avoid physical activities because they believe these activities may increase pain or cause further injury. Over time, avoidance behaviors may contribute to physical deconditioning, reduced muscle function, and increased functional impairment.

The Fear-Avoidance Beliefs Questionnaire is commonly used to assess individuals' beliefs regarding the relationship between pain, physical activity, and work-related activities. Higher levels of fear-avoidance beliefs have been associated with greater pain severity, increased disability, and poorer physical performance in individuals with low back pain.

Trunk muscle endurance plays a key role in maintaining spinal stability. Adequate endurance of the paraspinal and abdominal muscles supports mechanical stability of the spine and contributes to the safe performance of functional movements. The Biering-Sørensen Test and plank test are commonly used to assess trunk muscle endurance in clinical and research settings. The Biering-Sørensen Test evaluates the endurance of the trunk extensor muscles, whereas plank-based tests assess the endurance of the anterior and lateral trunk musculature.

Functional impairment in individuals with low back pain can be evaluated using the Oswestry Disability Index, a self-reported questionnaire that assesses limitations experienced during activities of daily living. Functional mobility and performance may also be evaluated using the Timed Up and Go test, which involves standing up from a chair, walking a short distance, turning, returning to the chair, and sitting down. This test reflects mobility, dynamic balance, and functional performance during daily activities.

Postural control and balance may also be affected in individuals with low back pain. Reduced static balance performance can negatively influence functional activities and mobility. The Single-Leg Stance Test is a practical clinical measure used to assess postural stability and static balance.

Although previous studies have examined associations between psychosocial factors and functional status in individuals with low back pain, studies evaluating the relationship between fear-avoidance beliefs, trunk muscle endurance, balance, and functional performance together remain limited. Identifying these relationships may contribute to the development of more comprehensive rehabilitation programs for individuals with lumbar disc herniation.

Study Overview

Status

Recruiting

Conditions

Disc Herniation

Study Type

Observational

Enrollment (Estimated)

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

Name: Kubra Kardes
Phone Number: 05387115631
Email: kubrakoce@gmail.com

Study Locations

Turkey (Türkiye)
- - Istanbul, Turkey (Türkiye), 34010
    - Recruiting
    - Istinye University
    - Contact:
      
      Kubra Kardes, Asst.Prof
      
      Phone Number: 05387115631
      
      Email: kubrakoce@gmail.com
    - Sub-Investigator:
      
      Kubra Kardes, Asst. Prof.

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

Adult
Older Adult

Accepts Healthy Volunteers

N/A

Sampling Method

Probability Sample

Study Population

The study will include volunteer individuals aged 18-65 who applied to a physiotherapy and rehabilitation clinic and were diagnosed with lumbar disc herniation.

Description

Inclusion Criteria:

Aged between 18 and 65 years
Clinically and/or radiologically diagnosed with lumbar disc herniation
Presence of low back pain for at least 3 months
Sufficient cognitive capacity to understand and perform the assessment procedures
Ability to walk independently
Willingness to participate voluntarily and provide written informed consent

Exclusion Criteria:

History of lumbar spine surgery
History of neurological disorders, such as stroke or Parkinson's disease
Vestibular disorders or severe balance impairment
History of orthopedic injury or surgery affecting the lower extremities
Presence of rheumatological disease
Pregnancy
Severe pain or an acute inflammatory condition that prevents completion of the assessment procedures

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

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Fear-Avoidance Beliefs Time Frame: 4 weeks	Fear-avoidance beliefs related to pain will be assessed using the Fear-Avoidance Beliefs Questionnaire. The Fear-Avoidance Beliefs Questionnaire is a self-reported questionnaire that evaluates individuals' fear-avoidance beliefs regarding pain in relation to physical activity and work-related activities. The questionnaire consists of 16 items and includes two subscales: the Physical Activity subscale and the Work subscale. Participants rate each statement on a Likert-type scale ranging from 0 (completely disagree) to 6 (completely agree). Higher scores indicate stronger fear-avoidance beliefs, suggesting greater concern that physical activity or work-related activities may worsen pain or cause further injury. Lower scores indicate fewer fear-avoidance beliefs and less perceived threat associated with movement and activity.	4 weeks
Lumbar Extensor Muscle Endurance Time Frame: 4 weeks	Lumbar extensor muscle endurance will be assessed using the Biering-Sørensen Test. During the test, participants will be positioned prone on a treatment table, with the pelvis and lower extremities stabilized. Participants will be instructed to maintain their upper body in a horizontal position with the trunk extending beyond the edge of the table. The duration for which the participant maintains this position will be recorded in seconds using a stopwatch. The test will be terminated if the participant is unable to maintain the required position, demonstrates a loss of alignment, or wishes to stop the test. A longer holding time indicates greater lumbar extensor muscle endurance, whereas a shorter holding time indicates reduced lumbar extensor muscle endurance.	4 weeks
Abdominal Muscle Endurance Time Frame: 4 weeks	Abdominal muscle endurance will be assessed using the plank test. Participants will assume a prone plank position with the elbows positioned under the shoulders and the toes in contact with the floor. They will be instructed to maintain the trunk in a straight line. The duration for which the position is maintained will be recorded in seconds using a stopwatch. The test will be terminated if trunk alignment is lost or if the participant is unable to continue. A longer holding time indicates greater abdominal muscle endurance and trunk stabilization capacity, whereas a shorter holding time indicates reduced abdominal muscle endurance.	4 weeks
Assessment of Functional Impairment Time Frame: 4 weeks	Functional impairment in activities of daily living will be assessed using the Oswestry Disability Index. The Oswestry Disability Index is a self-reported questionnaire that evaluates the impact of low back pain on daily activities. It consists of 10 sections, each containing six response options that reflect the individual's functional status during daily activities. Each section is scored from 0 to 5, and the total score is calculated as a percentage. Higher Oswestry Disability Index scores indicate greater functional impairment and disability related to low back pain, whereas lower scores indicate less functional impairment and better functional status.	4 weeks
Assessment of Functional Performance Time Frame: 4 weeks	Functional mobility and performance will be assessed using the Timed Up and Go test. Participants will begin in a seated position in a standard chair. Upon instruction, participants will stand up, walk three meters to a designated point, turn around, walk back to the chair, and sit down. The completion time will be measured in seconds using a stopwatch. A shorter completion time indicates better functional mobility, dynamic balance, and walking performance, whereas a longer completion time indicates reduced functional mobility and performance.	4 weeks
Assessment of Balance Performance Time Frame: 4 weeks	Static balance performance will be assessed using the Single-Leg Stance Test. Participants will be instructed to stand on one leg with their arms positioned alongside the body. The duration for which they are able to maintain balance while keeping the opposite foot off the floor will be recorded in seconds using a stopwatch. The test will be terminated if the raised foot touches the floor, the stance foot changes position, or balance is lost. The test may be performed on both the right and left legs, and the holding times will be recorded separately. A longer standing time indicates better static balance and postural stability, whereas a shorter standing time indicates reduced static balance performance.	4 weeks

Collaborators and Investigators

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

Sponsor

Istinye 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)

June 30, 2026

Primary Completion (Estimated)

September 30, 2026

Study Completion (Estimated)

October 30, 2026

Study Registration Dates

First Submitted

June 23, 2026

First Submitted That Met QC Criteria

June 23, 2026

First Posted (Actual)

June 29, 2026

Study Record Updates

Last Update Posted (Actual)

August 11, 2026

Last Update Submitted That Met QC Criteria

August 10, 2026

Last Verified

August 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

IstinyeU2333095101

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Studies a U.S. FDA-regulated device product

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.