Understanding the Dorsal Root Ganglia: Anatomy, Physiology, and its Implications in Chronic Pain Conditions

The dorsal root ganglia (DRG) serve as a pivotal relay in the transmission of sensory information, particularly nociception, from the periphery to the central nervous system. Situated in the intervertebral foramina, these pseudounipolar neurons integrate peripheral inputs and regulate excitability through a complex interplay of ion channels, neurotransmitters, and glial interactions. Alterations in sodium, potassium, and calcium channel dynamics contribute to abnormal action potential generation, sensitization, and spontaneous discharges—hallmarks of chronic pain states. This makes the DRG a central player in neuropathic pain, complex regional pain syndrome, radiculopathy, and post-herpetic neuralgia. Recent advances in interventional pain medicine have harnessed the DRG as a therapeutic target. Radiofrequency techniques, both thermal and pulsed, disrupt or modulate pain transmission with variable durations of relief. DRG neuromodulation has shown promise in refractory neuropathic pain, offering dermatomal specificity and targeted analgesia where conventional spinal cord stimulation may fail. Emerging evidence also supports novel therapies such as ozone injection at the DRG for post-herpetic neuralgia, leveraging its anti-inflammatory and neuromodulatory properties. This review outlines the anatomy and physiology of the DRG, with emphasis on the mechanisms of action potential generation, its role in chronic pain pathophysiology, and current interventional strategies. By bridging fundamental neurobiology with clinical applications, we highlight the DRG not only as a passive conduit of sensory signals but as an active, dynamic therapeutic target in modern pain medicine.