Multichannel Neuromuscular Electrical Stimulation With Core Exercise for Chronic Low Back Pain

Design and setting This is a prospective, three-arm, parallel-group, assessor-blinded randomized controlled trial conducted at the Semiha Atas Timurtas Private Health Professional Services Unit in Cizre, Sirnak, Turkey. Institutional permission for the study site has been obtained.

Participants Adults aged 18-55 years with chronic non-specific low back pain lasting at least three months are screened for eligibility. Eligible participants provide written informed consent before study procedures.

Randomization and masking Participants are randomized in a 1:1:1 ratio to one of three treatment groups. Participants and the treating physiotherapist cannot be blinded because of the nature of the interventions. Outcome assessments are performed by a physiotherapist who is unaware of group allocation. [DOLDURULACAK - random sequence generation and allocation concealment method, if available.]

Interventions All groups receive the same standardized core exercise program for six weeks, two sessions per week (12 sessions total). [DOLDURULACAK - exact core exercises, sets/repetitions, session duration, and progression criteria.] Group 1 additionally receives the StimaWELL 120MTRS lumbar strengthening program for 30 minutes at 40 °C during each treatment session.

Group 2 additionally receives the StimaWELL 120MTRS muscle relaxation program for 30 minutes at 40 °C during each treatment session.

Group 3 receives the core exercise program alone and does not receive StimaWELL 120MTRS treatment.

Outcome assessment Assessments are conducted before treatment (baseline/week 0) and after completion of the six-week program (week 6). Low back pain intensity is measured with a 100-mm Visual Analog Scale. Secondary outcomes include the Oswestry Disability Index, Patient-Specific Functional Scale, WHOQOL-BREF Turkish version, and Insomnia Severity Index.

Statistical analysis The planned sample size is 45 participants (15 per group). The sample-size calculation used G*Power 3.1.9 with an effect size of 0.25, alpha of 0.05, and power of 0.80, yielding a minimum required sample of 42; the target was increased to 45 to permit equal allocation. Group, time, and group-by-time interaction will be evaluated using a two-way mixed-design analysis of variance, with statistical significance set at p < 0.05.

Inclusion criteria

• Aged 18 to 55 years.
• Chronic non-specific low back pain lasting at least three months.
• Low back pain not attributable to a specific trauma, infection, tumor, fracture, rheumatologic disease, or serious neurological disorder.
• Pain intensity meeting the protocol threshold stated as VAS >=3. [TEYIT - because the outcome VAS is a 100-mm scale, clarify whether the intended eligibility threshold is >=30 mm (equivalent to 3/10) rather than >=3 mm.]
• Physical and cognitive ability to perform the core exercise program.
• Willingness to attend two treatment sessions per week for six weeks (12 sessions total).
• Voluntary participation and provision of written informed consent.

Exclusion criteria

• Age younger than 18 years or older than 55 years.
• Low back pain due to disc herniation, spinal stenosis, fracture, tumor, infection, or inflammatory disease.
• Nerve root involvement, marked sensory loss, or muscle weakness.
• Previous lumbar spine surgery.
• Pacemaker or other electronic implant; pregnancy; epilepsy; or active cancer.
• Open wound or skin disease in the treatment area.
• Physical therapy for low back pain within the previous month or continuation of another low back pain treatment during the study period.