Placebo-Induced Hypoalgesia During Transcutaneous Electrical Nerve Stimulation Application in Low Back Pain

Placebo-Induced Hypoalgesia During Transcutaneous Electrical Nerve Stimulation in Acute Low Back Pain

The primary goal of this clinical trial is to evaluate the feasibility of conducting a full-scale randomized controlled trial (RCT), considering recruitment, compliance with study protocols, and adverse events. The secondary goal is to evaluate the effectiveness of a video-based educational explanation of transcutaneous electrical nerve stimulation (TENS) in eliciting placebo-induced hypoalgesia and improving clinical outcomes in patients with acute low back pain.

The main question it aims to answer is: Does the addition of a video-based educational explanation of TENS to standard physical therapy rehabilitation, consisting of TENS and exercises, increase the pressure pain threshold, reduce pain intensity, and improve functional mobility, patient satisfaction, and quality of life in patients with acute low back pain?

Participants will be divided into two groups for comparison: the control group will receive standard physical therapy rehabilitation consisting of TENS and exercises, while the experimental group will receive the same program in addition to the video-based educational explanation of TENS.

Pain modulation through expectation is a well-established phenomenon. Anticipating relief from a treatment can enhance the effects of both pharmacological and non-pharmacological analgesic interventions. The expectation of pain relief can reduce the perceived intensity of stimuli and is associated with changes in brain regions involved in pain processing, including the thalamus, prefrontal cortex, and somatosensory cortices. Previous research suggests that expectation can have a moderate to large effect on experimental and acute procedural pain.

Based on this, the investigators hypothesize that adding a video-based educational explanation of TENS to a standard physical therapy rehabilitation program will enhance patient expectations regarding the intervention. This may elicit placebo-induced hypoalgesia and improve clinical outcomes in patients with acute low back pain.

Inclusion Criteria:

• acute low back pain without radicular pain to lower limbs
• minimal pain level of 4 on the 0-10 VAS
• 18-65 years of age
• TENS naïve or have not used TENS in the past 5 years.

Exclusion Criteria:

• Radicular pain to lower limbs
• Serious spinal disorders, such as fractures, tumors, or inflammatory arthritis disease
• Nerve root disorders confirmed by neurological tests
• Neurological diseases
• Severe cardiorespiratory disease
• Pregnancy
• Skin infection or lesions or change in sensation at the TENS application site
• Cancer
• Cardiac pacemaker
• Allergy to electrodes
• use of opioids.