Transcutaneous Electrical Nerve Stimulation Versus Repetitive Transcranial Magnetic Stimulation on Pain and Functional Outcome in Cervical Radiculopathy

Cervical Radiculopathy mostly occurs due to mechanical or inflammatory stimuli around the cervical nerve roots which is either due to disc herniation or osteophytes formation causing nerve root compression, inflammation or both but sometimes It can also be caused due to tumors, trauma, synovial cysts, meningeal cysts, dural arteriovenous fistula or tortous vertebral arteries.Transcutaneous electrical nerve stimulation (TENS) is a type of electrical stimulation which mostly aims for the symptomatic pain relief by stimulating the sensory nerve fibers either by pain gate mechanism or opioid system. As proposed by gate control theory, TENS produces an activation of inhibitory interneurons in the substantia gelatinosa in the dorsal horn of the spinal cord by the electric stimulation of large diameter fibres(A-beta -fibres), which inhibit the transmission of nociceptive signals from small diameter fibres (A delta and C) and as per opioid mechanism , it stimulates the release of endorphin, leading to vasodilation in the injured tissue.

Alternative non-pharmacological interventions using neuromodulation techniques have been proposed. Among them, repetitive transcranial magnetic stimulation (rTMS) applied over the primary motor cortex (M1) is the neuromodulation technique with the highest level of evidence, in the third- line treatment, to alleviate chronic neuropathic pain.

Owing to the limitations of current interventions, researchers are investigating the use of noninvasive brain stimulation techniques, such as repetitive transcranial magnetic stimulation (rTMS), in chronic pain management. rTMS holds promise because of its ability to modulate cortical activity, which in turn can help manage chronic pain. High-frequency rTMS applied to the motor cortex contralateral to the side of the worst pain has been shown to be effective in inducing analgesia (pain relief) in various pain conditions including fibromyalgia, neuropathic pain, migraine, and chronic low back pain (CLBP) .Therefore, the purpose of this study was to evaluate whether targeting both the central (via rTMS) and the peripheral nervous system (via TENS) leads to increased pain relief, decreased functional disability, and improved quality of life compared with targeting both the peripheral and central nervous system in patients with cervical radiculopathy.