tens placement for dorsal column stimulation

However, only the non-nociceptive fibers can activate the inhibitory cells, therefore closing the gate.Įven though the gate control theory was the initial guiding mechanism of action, modern research has demonstrated that the underlying mechanisms are not clearly understood. Both the nociceptive and non-nociceptive fibers can activate the transmission cells, opening the gate of signals sent to the brain. It establishes that C fibers, A-delta fibers (nociceptive), and A-beta fibers (non-nociceptive) can all carry information from the injury site to two different cell types in the dorsal horn of the spinal cord, transmission cells, and inhibitory neurons. The gate control theory of pain, mentioned above, is directly associated with these pain systems. These reactions include, but are not limited to, somatic and autonomic reflexes, negative or positive feedback to increase or reduce the pain, endocrine and emotional responses, cortical awareness, or the pain, as well as the memory of the event. Once the brain receives the pain signals, several reactions are generated almost immediately to modify and respond to these signals.

The primary integrative site in the brain is the thalamus, but other structures also participate in response to pain. Myelinated A-beta fibers (large non-nociceptive fibers, which conduct touch, pressure, and vibration)Ĭentral pathways (relay neuronal signals to higher brain structures) Unmyelinated C fibers and lightly myelinated A-beta fibers (small nociceptive fibers, which conduct pain) Nociceptive Fibers (peripheral pain receptors) They send this information to second-order neurons located in the spinal cord, mainly in the dorsal horn (central pathways), which are then transmitted via projection neurons to the brainstem (integrative neurons). First, nociceptors receive signals of noxious temperature, chemical, or mechanical stimuli (peripheral neurons). The interrelation between these three systems is responsible for the perceived sensation of pain and the responses associated with it. Multiple pain systems are responsible for the sensation of pain these systems are composed of integrative neuronal sets (conduct excitatory or inhibitory signals on the nociceptors). In other words, stimulation of the touch and vibration nerves “closes the gate” on ascending pain impulses that carry noxious pain stimuli cephalad. This interruption is facilitated by the common nerve synapse location in the substantia gelatinosa of the dorsal horn. In summary, they posed that pain impulses provoked in the periphery, which are carried by C fibers and A-delta fibers, could be interrupted by stimulating larger A-beta fibers. Neurostimulation modalities arose as a response to treating the gate control theory of pain by Melzack and Wall. A similar principle utilizes the central nervous system and the peripheral nervous system stimulation in deep/cortical brain stimulation and peripheral nerve stimulation, respectively. Presently, neuromodulation involves the implantation of leads in the epidural space. Initially, this technique applied pulsed energy in the intrathecal space. Spinal cord stimulation uses pulsed electrical energy near the spinal cord to manage pain.

Tens placement for dorsal column stimulation