The aim of this study is to investigate the effects of thoracolumbar fascia mobilization and ultrasound-guided thoracolumbar interfascial 5% dextrose injection on pain, range of motion, disability, quality of life, proprioception, and fascial thickness and echogenicity in patients with nonspecific chronic low back pain.

-Primary Objective: The primary objective is to evaluate the effects of these interventions on pain, functional status and range of motion.

-Secondary Objective: The secondary objective is to assess the long-term effects on quality of life, proprioception, fascial thickness, and echogenicity.

This study aims to compare the effectiveness of thoracolumbar fascia mobilization and ultrasound-guided thoracolumbar interfascial 5% dextrose injection in individuals with nonspecific chronic low back pain. The study will evaluate the impact of these interventions on pain intensity, lumbar range of motion, functional disability, quality of life, proprioception, and the structural characteristics of the thoracolumbar fascia.

The primary objective is to determine how these treatment approaches influence pain severity, functional status, and lumbar mobility. The secondary objective is to explore their potential long-term effects on quality of life, lumbar proprioception, and thoracolumbar fascia morphology, including fascial thickness and echogenicity.

Participants will be assigned to one of three groups. The first group will receive thoracolumbar fascia mobilization using standardized myofascial release techniques applied to the thoracolumbar fascia region. The intervention will be administered twice per week for three weeks, for a total of six treatment sessions. The procedure will be performed by the research team using standardized myofascial release techniques aimed at improving fascial mobility and reducing soft tissue restrictions.

The second group will undergo ultrasound-guided thoracolumbar interfascial injection with 5% dextrose. The procedure will be performed in the prone position using a high-resolution ultrasound device with a linear probe to identify the relevant paraspinal structures. A needle will be advanced into the interfascial plane of the posterior layer of the thoracolumbar fascia under ultrasound guidance, and 10 mL of 5% dextrose solution will be injected after confirming the absence of vascular puncture.

Participants in the third group will receive a combination of both interventions, including thoracolumbar fascia mobilization and ultrasound-guided interfascial dextrose injection, according to the protocols described above.

Outcome assessments will include pain intensity measured by the Visual Analog Scale (VAS), lumbar range of motion assessed with a digital inclinometer and the Modified Schober Test, and functional disability evaluated using the Oswestry Disability Index (ODI). Additional secondary outcomes will include quality of life measured with the Short Form-12 Health Survey (SF-12), ultrasound-based evaluation of thoracolumbar fascia thickness and echogenicity, and lumbar proprioception assessed through an active joint position sense test. All outcome measures will be recorded at baseline and at follow-up evaluations at one and three months after the intervention.

Participants eligible for inclusion in this study will be male or female patients aged between 18 and 65 years who have experienced low back pain lasting longer than three months and have not achieved adequate improvement with medical treatment. Participation in the study will be voluntary.

Participants will be excluded if they are younger than 18 years or older than 65 years, have a body mass index (BMI) greater than 30 kg/m², are pregnant or breastfeeding, have coagulation disorders, have a history of spinal surgery, have inflammatory or malignant diseases, have a local infection at the spine or injection site, have lumbar disc pathology causing radiculopathy, have spinal stenosis, spondylolysis, or spondylolisthesis, have participated in physical therapy or any manual therapy within the past six months, have received lumbar injections within the past six months, have a history of allergy to injection materials, or refuse to participate in the study.

Inclusion Criteria:

1. Male or female patients aged 18 to 65 years
2. Presence of low back pain lasting longer than 3 months
3. No adequate response to medical treatment
4. Voluntary participation in the study

Exclusion Criteria:

1. Age below 18 or above 65 years
2. Body mass index (BMI) greater than 30 kg/m²
3. Pregnancy or breastfeeding
4. Presence of coagulation disorders
5. History of spinal surgery
6. Presence of inflammatory or malignant diseases
7. Local infection at the spine or injection site
8. Presence of lumbar disc pathology causing radiculopathy
9. Presence of spinal stenosis, spondylolysis, or spondylolisthesis
10. Participation in physical therapy or any manual therapy within the past 6 months
11. Receiving lumbar injections within the past 6 months
12. History of allergy to injection materials
13. Refusal to participate in the study