Peripheral Nerve Field Stimulation for Chronic Pain: 100 Cases and Review of the Literature Pain Medicine
Pain Medicine. September 2011, Volume 12, Issue 9 Pages 1395-1405
Paul Verrills MD, David Vivian MD, Bruce Mitchell MD, Adele Barnard PhD
Abstract
Objective: To evaluate the clinical outcomes of 100 consecutive patients receiving peripheral nerve field stimulation (PNFS) for the treatment of chronic intractable pain. Design: Prospective, observational study. Setting: A private interventional pain specialty referral practice. Patients: One hundred consecutive private practice patients receiving PNFS for the treatment of chronic craniofacial, thorax, lumbosacral, abdominal, pelvic, and groin pain conditions.Outcome Measures: Pain (11-point numerical rating scale), complications, changes to analgesic use and employment status, disability (Oswestry or Neck Disability Indexes), depression (Zung Depression Index), and patient satisfaction. Results: We demonstrate an average pain reduction of 4.2·±·2.5 pain scale points on an 11-point scale following PNFS (preimplant pain score of 7.4·±·1.7 to a follow-up average of 3.2·±·2.3 pain scale points) (P·≤·0.00). At a follow-up period of 8.1·±·4.7 months (range 1–23 months), an overall 72% of patients reduced their analgesic use following PNFS. Patients receiving a lumbosacral PNFS for chronic low back pain reported a significant reduction in disability following treatment, as determined by the Oswestry Disability Index. Of the 100 cases, no long-term complications were reported. Conclusions: This prospective 100 consecutive PNFS patient outcome study demonstrates that PNFS can be a safe and effective treatment option for, otherwise, intractable chronic pain conditions. PNFS has the potential to fundamentally change the way we think about pain management
Subcutaneous Stimulation: How to Assess Optimal Implantation Depth
Neuromodulation: Technology at the Neural Interface. Volume 14, Issue 4, July/August 2011, Pages: 343–348,
David Abejón, Timothy Deer and Paul Verrills
Abstract
Introduction: Subcutaneous stimulation (peripheral nerve field stimulation) is a novel neuromodulation modality that has increased in its utilization during the last 10 years. It consists of introducing a lead in the subdermal level to stimulate the small nerve fibers in that layer. Unlike other neuromodulation techniques including direct peripheral nerve stimulation, spinal cord stimulation, or deep brain stimulation, the precise target is not identified. Materials and Methods: To date, there is no clear guideline on the appropriate depth or a method to achieve reproducibility of the appropriate depth to place these leads. From clinical experience, we have found that when electrodes are placed in a layer that is too superficial, stimulation is often painful or lacks efficacy. Further, if they are too deep, the patient may not feel adequate paresthesia or get uncomfortable stimulation including, in some circumstances, muscle contractions. Results: In this small series, we demonstrate a novel concept using a radiofrequency stimulation probe to identify the appropriate depth to place the lead. Reproducibility of results will add clarity to the accumulating data and hopefully increase the chances of adequate stimulation coverage and pain relief.
Link to Article: http://onlinelibrary.wiley.com/doi/10.1111/j.1525-1403.2011.00357.x/abstract
Pain Procedures in Clinical Practice
3RD EDITION. Ted A. Lennard, Stevan A. Walkowski, Aneesh K. Singla, David Vivian. Elsevier Publishing. 2011
Chapter 37 – Sacroiliac Joint Pain : Procedures for Diagnosis and Treatment. Bruce Mitchell, MM, BS, FACSP, David G. Vivian, MM, BS, FAFMM
Chapter 38 - Discography. Part A: Theoretical Aspects. David G.·Vivian,·MM, BS, FAFMM
Chapter 39 – Discogenic Pain, Internal Disc Disruption, and Radicular Pain. David G. Vivian, MM, BS, FAFMM
Chapter 40 – Intradiscal and Peridiscal Therapies for Discogenic and Radicular Pain. David G. Vivian, MM, BS, FAFMM
iSpine: Evidence-Based Interventional Spine Care
Michael DePalma, MD. Demos Medical 2011
Chapter 4. Diagnostic Imaging of Lumbosacral Internal Disc Disruption, Paul E. Verrills, Nikolai Bogduk, and David G. Vivian
Chapter 28. Pathophysiology of Painful Cervical Spine Disorders, David G. Vivian and Paul E. Verrills,
Penetration of a Cervical Radicular Artery During a Transforaminal Injection
Pain Medicine.·February 2010, Volume 11, Issue·2 Pages 229-231
Paul Verrills MD,·Gillian Nowesenitz,·Adele Barnard PhD
Abstract
Background: Inadvertent cannulation or penetration of the cervical radicular arteries during cervical transformaminal epidural injections (TFESIs) is a serious clinical risk, and purportedly, the cause of possible spinal cord injury sustained during this procedure. Case: Here, we present a case of inadvertent intravascular penetration of a cervical radicular artery during a C5–6 TFESI and demonstrate the best image capture to date of direct ramification of a cervical radicular artery into the anterior spinal artery. Conclusion. This observation reinforces the need for contrast injection and real-time digital subtraction fluoroscopy during cervical TFESIs for the prevention of spinal cord injury and fatalities.
Comment on: Prevalence and Correlates of Three Types of Pelvic Pain in a Nationally Representative Sample of Australian Women
Med J Aust. January 2009, Volume 190, Issue 1 Pages 47-8
David Vivian MBBS, Adele Barnard PhD
Comment Link: http://www.mja.com.au/public/issues/190_01_050109/letters_050109_fm-4.html
The incidence of intravascular penetration in medial branch blocks: cervical, thoracic, and lumbar spines.
Spine 2008 Mar 15;33(6):E174-7.
Paul Verrills, Bruce Mitchell, David Vivian, Gillian Nowesenitz, Brian Lovell, Chantelle Sinclair.
Abstract
STUDY DESIGN: Clinical observational study. OBJECTIVE: To quantify the incidence of inadvertent intravascular injections in spinal medial branch blocks in a clinical setting. SUMMARY OF BACKGROUND DATA: Previous research established the rate of inadvertent intravascular injection in lumbar medial branch blocks at 8%. The incidence of intravascular injection in cervical and thoracic medial branch blocks has not been reported previously. This study establishes the rate of inadvertent intravascular injection in patients receiving medial branch blocks of the cervical and thoracic spines. Further, this study reports a significantly lower rate of inadvertent intravascular injection for lumbar medial branch blocks than previously reported. METHODS: Patients were originally referred to the clinic, for diagnosis and treatment of chronic spinal origin somatic pain. Medial branch blocks were then performed as diagnostic procedures to confirm the zygapophysial joint(s) as the suspected source of pain. Blocks were performed by experienced practitioners on nonidentified patients over a 3-year period. Clinical observations were recorded for 14,312 separate medial branch block levels. The level of the spine and the incidence of inadvertent intravascular injections were recorded. RESULTS: This study demonstrates that the overall incidence of intravascular penetration in medial branch blocks is rare, with an overall rate of 3.5%. This study also establishes the rate of intravascular injection for levels within the spine: the cervical spine is likely to be intravascular 3.9% of the time and the lumbar spine 3.7%, whereas the thoracic spine is significantly lower, with just 0.7% injections reported as intravascular. Significant differences were also observed between individual vertebral levels. CONCLUSION: The false-negative rate for medial branch blocks is likely to be lower than previously reported. The rate of inadvertent intravascular injection for thoracic medial branch blocks is 0.7%. Cervical and lumbar medial branch blocks are associated with an overall rate of 3.9% and 3.7%, respectively. Although these rates are lower than previously reported, the incidence of false-negative blocks still justifies the use of contrast to confirm nonvascular injection.
Link to Article: http://journals.lww.com/spinejournal/Abstract/2008/03150/The_Incidence_of_Intravascular_Penetration_in.22.aspx
Peripheral Nerve Field Stimulation: Is Age an Indicator of Outcome?
Neuromodulation: Volume 12, Issue 1, January 2009, Pages: 60–67
Paul Verrills, Bruce Mitchell, David Vivian and Chantelle Sinclair
Abstract
Objective. This study aims to assess peripheral nerve field stimulation as a treatment option for chronic pain and test for indicators of outcome. Materials and Methods. We reviewed all patients permanently implanted with peripheral nerve field stimulators over the past 24 months. A questionnaire was used to assess outcomes. Results. Twenty-seven questionnaires were sent out and 23/27 responded. A significant average decrease of 4.02 visual analog scale points was observed. The average pain decrease for the low back was 3.77 points and 5.9 for occipital implants. An age effect was detected; younger patients (<60 years) reported an average pain relief of 4.79 points while older patients (>61 years) reported an average pain relief decrement of only 2.83 points. Most patients reported decreases in analgesic use after treatment. Pain relief was significantly and highly correlated with reduced analgesic intake and patient satisfaction. Conclusion. Peripheral nerve field stimulation is a safe, reversible, and effective treatment option for patients with chronic pain, particularly those under 60 years.
Link to Article: http://onlinelibrary.wiley.com/doi/10.1111/j.1525-1403.2009.00190.x/abstract
Peripheral Nerve Stimulation: A Treatment for Chronic Low Back Pain and Failed Back Surgery Syndrome?
Neuromodulation: Technology at the Neural Interface. Volume 12, Issue 1, January 2009, Pages: 68–75
Paul Verrills, Bruce Mitchell, David Vivian and Chantelle Sinclair
Abstract
Objective. This study aims to evaluate the usefulness of peripheral nerve stimulation as a treatment option for patients with chronic low back pain. Materials and Methods. More than 12 months, we collected data on consecutive patients who had successful trials and were subsequently implanted with octrode percutaneous leads placed subcutaneously within the major area of pain. Eleven patients met diagnostic criteria for failed back surgery syndrome. A questionnaire assessed outcomes including: pain, analgesic use, and patient satisfaction. The response rate was 93% (13/14): average follow-up time was seven·months. Results. There was a significant decrease in pain levels: an average reduction of 3.77 visual analog scale points. Eleven patients (85%) reported successful outcomes and an average pain reduction of 4.18 points but two reported a poor response. Pain relief was highly correlated with reduced analgesia and patient satisfaction. No complications were reported. Conclusion. This study demonstrates a treatment option that is safe, nonpharmacologic, reversible, and effective for patients with chronic low back pain that have exhausted other treatment options.
Link to Abstract: http://onlinelibrary.wiley.com/doi/10.1111/j.1525-1403.2009.00191.x/abstract
Interventions in Chronic Low Back Pain
Australian Family Physician: Back Pain. Vol 33(6):385-480; 2004.
Paul Verrills, David Vivian
Abstract
Chronic low back pain presents a major challenge for general practitioners and is a significant drain on community resources. Patients often feel frustrated by modern medicine's apparent failure to validate their symptoms with a specific diagnosis and management plan. This article presents an evidence based guide to current interventions, including an algorithm for the intervent-ional diagnostic workup of low back pain that has persisted beyond 3 months. Modern imaging techniques rarely determine the cause of pain. The GP must look for ‘red flag’ clues in the history. Management of low back pain includes NSAIDs, simple injections of plain local anaesthetic without adrenalin or cortisone, referral to a masseuse, physiotherapist and/or a musculoskeletal pain physician. Specific management includes medial branch and sacroiliac joint blocks, and radiofrequency neurotomy. Patients with long term pain may be referred to a psychologist for cognitive behavioural therapy.