Efficacy of the Gelstix nucleus augmentation device for the treatment of chronic discogenic low back pain: protocol for a randomised, sham-controlled, double-blind, multicentre trial.

INTRODUCTION Discogenic pain is the cause of pain in 26%-40% of patients with for low back pain. Consensus about treatment of chronic discogenic low back pain is lacking and most treatment alternatives are supported by limited evidence. The percutaneous implantation of hydrogels into the nucleus pulposus represents a promising regenerative intradiscal therapy. The hydrogel 'GelStix' is composed primarily of hydrolyzed polyacrylonitrile and acts as a reservoir of hydration, producing increased pressure and improved pH balance, potentially leading to disc preservation. We hypothesise that treatment with GelStix will lead to greater reduction in pain intensity at 6 months post-treatment compared with patients receiving sham treatment. METHODS AND ANALYSIS This is a parallel group, randomised sham-controlled double-blind, multicentre trial to assess whether the GelStix device is superior to sham in reducing pain intensity in patients with chronic discogenic low back pain. The study will be conducted in two regional hospitals in Europe. Seventy-two participants will be randomised in a 1:1 ratio. The primary outcome will be the change in pain intensity between preoperative baseline and at 6 months postintervention. Secondary outcomes were disability, quality of life, the patient's global impression of change scale, the use of pain medication and the disc degeneration process assessed by means of MRI. For change in pain intensity, disability, health-related quality of life and disc height, mean values will be compared between groups using linear regression analysis, adjusted for treatment centre. ETHICS AND DISSEMINATION Ethics approval was obtained from the Ethics Committee of the Canton Ticino, Switzerland (CE2982) and by the Medical Ethical Committee Arnhem-Nijmegen, the Netherlands (2016-2944). All patients that agree to participate will be asked to sign an informed consent form. Results will be disseminated through international publications in peer-reviewed journals, in addition to international conference presentations. TRIAL REGISTRATION NUMBER NCT02763956. PROTOCOL VERSION 7.1, 18 November 2020

Spinal cord stimulation in severe pharmacoresistant restless legs syndrome-two case reports.

Restless legs syndrome is a prevalent, sleep-related sensorimotor disorder with relevant impact on the patients' quality of life. For patients suffering from severe, pharmacoresistant restless legs syndrome, few therapeutic options remain to alleviate symptoms. In this case series, two patients with severe, pharmacoresistant restless legs syndrome were treated with epidural spinal cord stimulation and repeatedly assessed with polysomnography, including sleep structure and periodic limb movements as objective biomarkers not subject to placebo effects, during a 6-month follow-up period. One of the patients experienced excellent short- and long-term efficacy on subjective symptom severity (International RLS Study group rating scale 1 vs. 34 points at 3 months) and objective sleep parameters such as sleep architecture and periodic limb movements during sleep, while the second patient only reported short-term benefits from spinal cord stimulation. Ultimately, both patients opted for removal of the device for inefficacy. Based on the complex pathophysiology of restless legs syndrome and presumed mechanism of action of spinal cord stimulation in chronic pain disorders, we provide a detailed hypothesis on the possible modulating effect of spinal cord stimulation on the key symptoms of restless legs syndrome. Apart from describing a new therapeutic option for pharmacoresistant restless legs syndrome, our findings might also provide further insights into the pathophysiology of the syndrome

Efficacy of Cervical Facet Joint Radiofrequency Ablation Using a Multitined Cannula, a Technical Note, and Observational Study

Background: Chronic cervical facet joint pain is a leading cause of pain and disability. In patients nonresponsive to conservative treatment, cervical facet radiofrequency ablation (RFA) has shown to be efficacious. However, the conventional RFA technique can be cumbersome. A novel RFA technique with a multitined cannula allows for a lateral approach and represents an attractive alternative option for cervical facet RFA. It offers a potentially shorter, less cumbersome procedure, with consequently less x-ray exposure and patient discomfort than the conventional cervical RFA. Objectives: To describe the novel RFA technique using the lateral approach with the multitined cannula at the cervical facet joints and to assess its efficacy in chronic cervical facet joint pain. Study Design: This is a single-center observational study. Setting: Interventional Pain Management Center, Switzerland. Methods: The aim of this study is to describe the RFA technique using the lateral approach with the multitined cannula at the cervical facet joints and to assess its efficacy in chronic cervical facet joint pain. Eligible adult patients with chronic (> 3 months) cervical facet joint pain refractory to conservative treatment and confirmed by dual positive medial branch blocks, received a fluoroscopic-guided cervical facet RFA treatment using the multitined cannula. The primary outcome was pain relief. Secondary outcome measures included the proportion of patients reporting a = 30% reduction of pain intensity 2 months after RFA, patient global impression of change (PGIC), need for pain medication, sleep quality, and patient satisfaction. Results: We included 26 patients. The patients showed a clinically meaningful and significant pain relief at 2 months after cervical facet RFA (mean Numeric Rating Scale of 7.5 [1.9] at baseline to 4.2 [2.4]) and 58% of the patients reported = 30% reduction of pain. An improvement on the PGIC was reported by 88.2% of the patients. No severe side effects or complications were observed. Limitations: Key limitations of our study were the relatively small sample size, the lack of a control group, and a relatively short-term follow-up duration. Conclusions: Our results suggest that cervical facet joint RFA using the novel technique with the multitined cannula results in significant pain reduction and improvement on the PGIC. While the conventional technique requires multiple ablations at each target level, the RFA with the multitined needle requires only a singular ablation, likely sparing time, radiation dose, discomfort, and costs. Our results merit consideration of replacement of the conventional technique with the novel technique using the multitined cannula. However, larger-scale clinical trials with an adequate long-term follow-up period are needed to prove the efficacy of RFA using the multitined cannula in cervical facet joint pain

Dorsal root ganglion stimulation for painful small fiber neuropathy: A case report

Small fiber neuropathy is a disorder of the peripheral nerves with typical symptoms of burning, sharp, and shooting pain and sensory disturbances in the feet. Pain treatment depends principally on the underlying etiology with concurrent administration of antidepressants, anticonvulsants, opioids, and topical treatments like capsaicin and local anesthetics. However, treatments for pain relief in these patients frequently fail. We describe the first case of intractable painful small fiber neuropathy of the foot successfully treated with spinal cord stimulation of the left L5 dorsal root ganglion. A 74-year-old man presented at our clinic with severe intractable pain, dysesthesia, and allodynia of the left foot caused by idiopathic small fiber neuropathy, confirmed by skin biopsy. His pain score was 8 on a standard 0 – 10 numeric rating scale. As the pain was not satisfactorily controlled by conventional therapy, dorsal root ganglion stimulation was proposed to the patient and, after informed consent, a specifically designed percutaneous stimulation lead was placed over the left L5 dorsal root ganglion and connected to an external neurostimulator. After a positive trial of 10 days, a permanent neurostimulator was implanted. Twenty months post-implantation the patient continued to experience stimulation-induced paresthesia covering the entire pain area and reported a pain rating of 4. Results from the case report demonstrate that the dorsal root ganglion is a promising neural stimulation target to treat neuropathic pain due to intractable small fiber neuropathy. Prospective controlled studies are warranted to confirm the efficacy of this treatment as an option for the aforementioned condition

Refill Procedures of Intrathecal Drug Delivery Systems With a Recessed Fill Port on the Pump Surface: A Prospective Comparison Study of Ultrasound-Guided vs. Blind Refill Technique

Objectives: Structural differences of implantable drug delivery systems (IDDSs) might have an impact on the efficiency of needle access to the reservoir fill port (RFP). The aim of this study was to assess the efficiency of RFP needle access with an ultrasound (US)-guided vs. a blind refill technique in IDDSs with a Recessed RFP (Recessed-RFP-IDDS). Materials and Methods: The primary outcome was the number of attempts needed to enter the RFP with a needle comparing the US-guided technique vs. the blind refill technique. The time to enter the RFP with the needle was a secondary outcome. We compared the amount of attempts between both techniques with the non-parametric Wilcoxon rank sum test. Results: Fourteen adult patients underwent a total of 75 refills of their Recessed-RFP-IDDS during a period of 24 months. The median number of attempts to enter the RFP did not differ significantly between the US-guided technique and the blind refill technique (2.0 (IQR: 1–5) vs. 1.5 (IQR: 1–5.0), p = 0.572). The median time to enter the RFP with the needle did not differ significantly between both techniques (35.0 sec (IQR: 26.0–58.0) vs. 41.0 sec (IQR: 25.5–46.8), p = 0.878). Conclusion: The results of this study suggest that there is no difference in the RFP needle access efficiency between the US-guided and the blind refill technique in superficially located Recessed-RFP-IDDSs, if performed by experienced practitioners. However, the study did not address efficiency of the RFP needle access in IDDSs with aberrancy in pump location or refills performed by inexperienced staff