Uterine Position and Pain and Central Sensitization Parameters in Women With Chronic Low Back Pain

The Relationship Between Uterine Position and Pain and Central Sensitization Parameters in Women With Chronic Low Back Pain

Female patients aged 18-75 years with chronic low back pain (lasting at least 3 months) will be included in the study. Demographic data including age, height, weight, educational status, marital status, and comorbidities will be recorded. In addition, clinical characteristics such as pain duration, pain distribution, analgesic use, and concomitant musculoskeletal disorders will be assessed.

Uterine position will be evaluated based on pelvic magnetic resonance imaging (MRI) or pelvic ultrasonography reports obtained within the last year. According to uterine position, participants will be divided into two groups: posteriorly positioned uterus (retroverted and/or retroflexed uterus) and anteriorly positioned uterus (anteverted uterus).

Pain severity will be assessed using the Visual Analog Scale (VAS), and pain duration will be recorded in months. Pressure pain threshold measurements will be performed using an algometer at bilateral lumbar paraspinal muscles, gluteal regions, and the mid-deltoid muscle as a remote control point.

Central sensitization will be assessed using the Central Sensitization Inventory (CSI), and pain catastrophizing will be evaluated using the Pain Catastrophizing Scale (PCS).

All assessments will be conducted through face-to-face interviews. No additional laboratory tests, interventional procedures, or treatments will be applied to the participants within the scope of the study. Validated Turkish versions of all scales will be used. The collected data will be analyzed to investigate the relationship between uterine position and pressure pain threshold, central sensitization, and pain catastrophizing levels in women with chronic low back pain.

Study Overview

• Status: Completed
• Conditions: Low Back Pain
• Intervention / Treatment: Other: No intervention

• Study Type: Observational
• Enrollment (Actual): 128

Contacts and Locations

Study Locations

• Turkey (Türkiye)
  • Istanbul, Turkey (Türkiye), 34192
    • Istanbul Physical Medicine Rehabilitation Training and Research Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: N/A

• Sampling Method: Probability Sample

Study Population

The study population will consist of female patients aged 18-75 years with chronic low back pain (lasting at least 3 months) who are admitted to the Physical Medicine and Rehabilitation outpatient clinics of Bakırköy Dr. Sadi Konuk Training and Research Hospital and Istanbul Physical Therapy and Rehabilitation Training and Research Hospital during the study period. Participants will be recruited consecutively. Only patients with available pelvic MRI and/or ultrasonography within the last year allowing classification of uterine position will be included. All participants will be medically stable and able to complete the study assessments.

Description

Inclusion Criteria:

Female, aged 18-75 years Presence of chronic low back pain (lasting at least 3 months) Availability of pelvic MRI and/or pelvic ultrasonography within the last year with assessable uterine position (anteverted, retroverted, retroflexed) Ability to read and understand Turkish and complete questionnaires Willingness to participate

Exclusion Criteria:

Pregnancy or childbirth within the last 6 months (postpartum period) History of lumbar spine surgery, vertebral fracture, or spinal malignancy Presence of inflammatory rheumatic disease (e.g., ankylosing spondylitis), severe neurological disease, or systemic disease affecting low back pain Severe cognitive impairment, communication problems, or major psychiatric disorder preventing participation Absence of pelvic imaging or inability to classify uterine position

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Group 1; Retrovert uterus	Other: No intervention; No intervention
Group 2; Antevert uterus	Other: No intervention; No intervention

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pressure Pain Threshold (PPT)	Pressure pain threshold (kg/cm²) will be measured using an algometer at bilateral lumbar paraspinal muscles, gluteal regions, and the mid-deltoid muscle as a remote control point. Lower values indicate increased pain sensitivity.	Baseline

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Visual Analog Scale (VAS)	Pain intensity will be assessed using a 10-cm visual analog scale, where higher scores indicate greater pain severity.	Baseline
Central Sensitization Inventory (CSI)	CSI scores range from 0 to 100, with higher scores indicating greater central sensitization.	Baseline
Pain Catastrophizing Scale (PCS)	The PCS assesses catastrophic thinking related to pain. Higher scores indicate greater pain catastrophizing.	Baseline

Collaborators and Investigators

• Sponsor: Istanbul Physical Medicine Rehabilitation Training and Research Hospital

Study record dates

Study Major Dates

• Study Start (Actual): March 16, 2026
• Primary Completion (Actual): April 16, 2026
• Study Completion (Actual): April 16, 2026

Study Registration Dates

• First Submitted: April 18, 2026
• First Submitted That Met QC Criteria: April 18, 2026
• First Posted (Actual): April 23, 2026

Study Record Updates

• Last Update Posted (Actual): April 23, 2026
• Last Update Submitted That Met QC Criteria: April 18, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Back Pain; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Low Back Pain
• Other Study ID Numbers: istftreah155

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No