Mechanisms for the Clinical Utility of Low-Frequency Stimulation in Neuromodulation of the Dorsal Root Ganglion.

Background: Dorsal root ganglion stimulation (DRG-S) involves the electrical modulation of the somata of afferent neural fibers to treat chronic pain. DRG-S has demonstrated clinical efficacy at frequencies lower than typically used with spinal cord stimulation (SCS). In a clinical study, we found that the frequency of DRG-S can be tapered to a frequency as low as 4 Hz with no loss of efficacy.

Very Low Frequencies Maintain Pain Relief From Dorsal Root Ganglion Stimulation: An Evaluation of Dorsal Root Ganglion Neurostimulation Frequency Tapering.

Background: Dorsal root ganglion neurostimulation (DRG-S) is effective in treating various refractory chronic pain syndromes. In preclinical studies, DRG-S at very low frequencies (<5 Hz) reduces excitatory output in the superficial dorsal horn. Clinically, we have also observed the effectiveness of DRG-S at low frequencies.

The Pathways and Processes Underlying Spinal Transmission of Low Back Pain: Observations From Dorsal Root Ganglion Stimulation Treatment.

Background: Dorsal root ganglion stimulation (DRG-S) is a novel approach to treat chronic pain. Lead placement at L2 has been reported to be an effective treatment for axial low back pain (LBP) primarily of discogenic etiology. We have recently shown, in a diverse cohort including cases of multilevel instrumentation following extensive prior back surgeries, that DRG-S lead placement at T12 is another promising target.

CRPS: what's in a name? Taxonomy, epidemiology, neurologic, immune and autoimmune considerations.

This account of the condition now termed complex regional pain syndrome (CRPS) spans approximately 462 years since a description embodying similar clinical features was described by Ambroise Paré in 1557. While reviewing its historical origins, the text describes why it became necessary to change the taxonomies of two clinical syndromes with similar pathophysiologies to one which acknowledges this aspect but does not introduce any mechanistic overtones. Discussed at length is the role of the sympathetic component of the autonomic nervous system (ANS) and why its dysfunction has both directly and indirectly influenced our understanding of the inflammatory aspects of CRPS.

An updated interdisciplinary clinical pathway for CRPS: report of an expert panel.

The goal of treatment in patients with complex regional pain syndrome (CRPS) is to improve function, relieve pain, and achieve remission. Current guidelines recommend interdisciplinary management, emphasizing 3 core treatment elements: pain management, rehabilitation, and psychological therapy. Although the best therapeutic regimen or the ideal progression through these modalities has not yet been established, increasing evidence suggests that some cases are refractory to conservative measures and require flexible application of the various treatments as well as earlier consideration of interventions such as spinal cord stimulation (SCS).