The Role of the Dorsal Root Ganglion in Cervical Radicular Pain: Diagnosis, Pathophysiology, and Rationale for Treatment

Abstract

Cervical radicular pain affects 83 per 100,000 adults annually. Diagnosis by means of physical examination, imaging, and electrophysiological studies is characterized by high specificity but low sensitivity. In this review, we focus on the role of the dorsal root ganglion and those treatment modalities that aim at pathophysiological mechanisms occurring after injury to the dorsal root ganglion. Cervical nerve injury initiates multiple events that lead to changes in nerve function and result in spontaneous firing at the dorsal root ganglion. Among these, inflammation and changes in ion-channel function play a pivotal role. Although many treatment modalities are described in the literature, the available evidence for efficacy does not allow us to formulate definitive conclusions on the optimal therapy. A lack of evidence is reported for cervical spine surgery. Interlaminar epidural steroid administration and radiofrequency techniques adjacent to the cervical dorsal root ganglion have the highest, but still weak recommendations.

Application of Pulsed Radiofrequency Currents to Rat Dorsal Root Ganglia Modulates Nerve Injury–Induced Tactile Allodynia

“…Nevertheless, inclusion of other behavioral testing modalities in pain models is also recommended in future experiments. Since spontaneous (37), enhanced (38) DRG activities, and sustained ectopic DRG neuron firing (39) are the main cause of radicular pain, DRG is likely the most important target to limit ectopic impulse generation in patients with radicular pain. Thus, the allodynia reversal effect of PRF may be applicable to both radicular pain because well as peripheral neuropathic pain as both animal models produce similar allodynic outcomes (40).…”

Stress enhances muscle nociceptor activity in the rat

“…However, chronic stress is known to upregulate Na + channels 66 , and the sympathoadrenal stress hormone, epinephrine, enhances tetrodotoxin-resistant Na + currents in dorsal root ganglion neurons 31 . We have provided evidence that stress can induce neuroplasticity in peripheral sensitization mechanisms in skin and muscle in the rat 28-30,56 and even induce mechanical hyperalgesia 20 .…”

A posterior approach to cervical nerve root block and pulsed radiofrequency treatment for cervical radicular pain: a retrospective study

“…In the large majority of the case though, it is caused by a combination of factors including narrowing of the intervertebral foramen, intervertebral disc herniation, osteoarthritis of facet joints, and spondylolisthesis of cervical spine, collectively known as cervical spondylosis. Nerve root compression due to trauma, abscess, hematoma, or tumor is relatively rare but must not be overlooked [1][2][3].…”