Advanced methods of spinal stimulation in the treatment of chronic pain: pulse trains, waveforms, frequencies, targets, and feedback loops.

INTRODUCTION: Spinal cord stimulation has emerged as a state-of-the-art evidence-based treatment for chronic neuropathic pain and mixed nociceptive-neuropathic pain. In recent years, several newer devices and treatment algorithms have provided unique and effective ways of treating chronic pain by spinal cord stimulation. In a previous review, the authors commented on the 5-year forecast for high frequency and Burst waveforms, as the only two paresthesia independent SCS strategies. Over the last 5 years, there has been considerable addition to the outcome data related to these modalities. Additionally, new treatment algorithms and modalities for spinal cord stimulation have emerged. In this review, the authors provide an up to date summary of these modalities of treatment, indications, and evidence on all different modalities and programming paradigms that are available today. AREAS COVERED: A literature review was performed using key bibliographic databases to find outcomes related studies pertaining to spinal cord stimulation, limited to the English language and human data, between 2010 and 2018. The literature search yielded the following based on our inclusion criteria; six articles on burst stimulation, three articled on high density/high dose stimulation, six articles on Dorsal Root Ganglion stimulation, nine articles on high-frequency stimulation, and one article on closed-loop stimulation. We have also included in the discussion some smaller and anecdotal studies. EXPERT COMMENTARY: The evidence to support outcomes of spinal cord stimulation has evolved considerably since our last review in 2014. New targets, frequencies and pulse trains, and feedback appear to have advanced the efficacy of spinal cord stimulation. Future developments aim to continue to refine patient selection and maintenance of patients in therapy.