Thoracolumbar Fascia Thickness in Women With Fibromyalgia

This prospective cross-sectional observational study aims to compare thoracolumbar fascia thickness between women with fibromyalgia and healthy female controls using ultrasonography. Thoracolumbar fascia thickness will be measured bilaterally at the L2-L3 and L4-L5 levels. Secondary analyses will evaluate the relationships between thoracolumbar fascia thickness and pain intensity, fibromyalgia-related functional impact, widespread pain, and symptom severity in participants with fibromyalgia.

Inclusion Criteria: * Female sex * Age between 18 and 65 years * For the fibromyalgia group, diagnosis of fibromyalgia according to the 2016 revised American College of Rheumatology criteria * For the healthy control group, absence of fibromyalgia or chronic widespread pain * Willingness to participate and provision of written informed consent Exclusion Criteria: * Pregnancy * Previous lumbar surgery or severe spinal deformity * Active infection, malignancy, or systemic inflammatory disease * History of trauma or surgery, or presence of a skin lesion at the ultrasonographic measurement site * Inability to complete the study assessments or provide informed consent