Volume 1 • Issue 1 • 1000101 J anesthesiol pain res, an open access journal Case Report Open Access Rejaei and Brenner, J anesthesiol pain res 2017, 1:1 Journal of Anesthesiology and Pain Research J o u r n a l o f A n e s t h e s i o l o g y a n d P a i n R e s e a r c h *Corresponding author: Damoon Rejaei, Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA, Tel:707-330-2583; E-mail: damoonrejaei@gmail.com Received: September 25, 2017; Accepted: October 04, 2017; Published: October 11, 2017 Citation: Rejaei D, Brenner GJ (2017) Blinded Efficacy Testing of High Frequency Spinal Cord Stimulation. J anesthesiol pain res 1: 101. Copyright: © 2017 Rejaei D, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Blinded Efficacy Testing of High Frequency Spinal Cord Stimulation Damoon Rejaei* and Gary J Brenner Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA Keywords: Spinal cord stimulation; Post-laminectomy syndrome; Chronic pain Introduction e first documented use of spinal cord stimulation (SCS) dates to 1967 when the American neurosurgeon C Norman Shealy described the subdural placement of an electrode to treat intractable pain in a 70 year-old patient suffering from a bronchial carcinoma [1]. Over the last fiſty years as the technology has improved and supporting outcome data accrued, SCS has gained increased acceptance for the treatment of a variety of chronic pain conditions. SCS is currently approved by the FDA for chronic pain of the trunk and limbs, intractable low back pain, leg pain, and pain from post-laminectomy syndrome. In Europe, it has additional approval for refractory angina pectoris and peripheral limb ischemia. Despite the empirical evidence for efficacy, the mechanism(s) through which SCS alters pain perception is unclear. While the primary site of action of SCS is local, there are multiple structures that may be affected including the dorsal root ganglia (DRG), central processes of peripheral sensory fibers, cells of the dorsal horn (second order sensory neurons, interneurons, glia), and white matter tracks both ascending and descending. Other proposed mechanisms of action include the release of inhibitory neurotransmitters within the dorsal horn including serotonin, acetylcholine and γ-aminobutyric acid (GABA), and inhibition of nociceptive conduction through the activation of large A-fibers [2]. Clearly, for a subset of patients a placebo effect is likely active, particularly given the fact that SCS represents a relatively high degree of invasiveness [3]. Traditional low-frequency SCS delivers pulse frequencies (typically around 50 Hz) with the goal of creating paresthesias overlapping with the patient’s pain distribution to mask pain perception [4]. Given tradiational SCS’s dependency on inducing paresthesias, it is difficult to blind patients and investigators to treatment; this is a major limitation for design of clinical trials for which efficacy is a primary outcome measure. In October 2015 the first randomized, controlled trial comparing traditional SCS with high frequency SCS at 10 kHz (HF10) for the treatment of chronic back and leg pain was published [4], and HF10 therapy was approved by the FDA in April 2016. Notably, HF10 therapy does not rely on the induction of paresthesias to mask pain, nor does HF10 induce any sensation in the patient, for that matter. Instead, HF10 has been empirically shown to decrease pain via delivery of high frequency pulses centered at the T8-T11 spinal region [5]. Given this “parestheia-free” technique, the prior limitation of blinding study subjects and investigators to treatment is obviated. However, to our knowledge no randomized control trial with blinding to treatment designed to evaluate efficacy of HF10 therapy has been published. In this report, we present a case of a patient who underwent permanent implantation of the HF10 SCS device and underwent ‘blinded’ testing of devise efficacy by her spouse who without her knowledge repeatedly inactivated (and subsequently activated) the stimulator while she slept. Case Presentation Approval was obtained from the patient for publication of this report. A 66 year-old female presented to our clinic with four years of chronic axial and radicular low back pain in 2012. Her past medical history was significant for migraines, fibromyalgia, chronic opioid use and asthma. Her past surgical history was significant for lumbar spondylosis status post L4-5 decompressive laminectomy and fusion with no relief of her axial or radicular back pain. Subsequently, she underwent an L2-S1 decompression and fusion in 2015 with improvement in her radicular pain, but continued to have residual axial back pain located to her bilateral lower back. e pain was burning in quality. Exacerbating Abstract Objective: Traditional spinal cord stimulation (SCS) relies on paresthesias to mask patients’ pain perception. This restricts the high-quality evaluation of SCS’s efficacy. 10-kHz high-frequency (HF10) therapy, however, is a paresthesia-free modality of SCS. As such, the introduction of this technology creates the opportunity to evaluate SCS’s efficacy with appropriate patient and provider blinding to treatment. We report a case of a patient with axial low back pain who, without her knowledge, underwent “blinded” testing of the device by her spouse. Case: A 66 year-old female with four years of axial low back pain and a diagnosis of post-laminectomy syndrome presented for consultation after failing multiple medical and surgical treatments. HF10 SCS trial provided her with greater than 50% pain relief with reduction in her opioid consumption. As such, decision was made to pursue permanent implantation. Without her knowledge, the patient underwent ‘blinded’ testing of the devise’s efficacy by her spouse who repeatedly inactivated (and subsequently activated) the stimulator while she slept. Discussion: This is the first report to evaluate the efficacy of HF10 in treating chronic axial low back pain where the patient was truly blinded to the SCS treatment (i.e., she did not know if the device was on or off). Future studies can lead to appropriately blinded randomized control studies to generate high-level evidence for HF10’s efficacy and harm in a variety of pain condition.