bluuebunny/crossref_metadata_2025 huggingface dataset:
Evidence-Based Medicine, Systematic
Reviews, and Guidelines in Interventional Pain
Management: Part 2: Randomized Controlled
Trials
Authors: Manchikanti Laxmaiah
Published: March 2021

Evidence-based medicine (EBM) is a shift in medical paradigms and about solving clinical problems, acknowledging that intuition, unsystematic clinical experience, and pathophysiologic rationale are insufficient grounds for clinical decision-making. The importance of randomized trials has been created by the concept of the hierarchy of evidence
in guiding therapy. Even though the concept of hierarchy of evidence is not absolute,
in modern medicine, most researchers synthesizing the evidence may or may not follow
the principles of EBM, which requires that a formal set of rules must complement medical training and common sense for clinicians to interpret the results of clinical research.
N of 1 randomized controlled trials (RCTs) has been positioned as the top of the hierarchy followed by systematic reviews of randomized trials, single randomized trial, systematic review of observational studies, single observational study, physiologic studies,
and unsystematic clinical observations. However, some have criticized that the hierarchy of evidence has done nothing more than glorify the results of imperfect experimental designs on unrepresentative populations in controlled research environments above
all other sources of evidence that may be equally valid or far more applicable in given
clinical circumstances.
Design, implementation, and reporting of randomized trials is crucial. The biased interpretation of results from randomized trials, either in favor of or opposed to a treatment, and lack of proper understanding of randomized trials, leads to a poor appraisal of the quality.
Multiple types of controlled trials include placebo-controlled and pragmatic trials. Placebo-controlled RCTs have multiple shortcomings such as cost and length, which limit the
availability for studying certain outcomes, and may suffer from problems of faulty implementation or poor generalizability, despite the study design which ultimately may not be
the prime consideration when weighing evidence for treatment alternatives. However,
in practical clinical trials, interventions compared in the trial are clinically relevant alternatives, participants reflect the underlying affected population with the disease, participants come from a heterogeneous group of practice settings and geographic locations,
and endpoints of the trial reflect a broad range of meaningful clinical outcomes.
Key words: Randomized controlled trial (RCT), placebo-controlled trial, pragmatic
controlled trial, randomization, allocation concealment, sample size, blinding, consolidated standards of reporting trials (CONSORT) statement, minimal clinically important
change (MCIC), minimal clinical important difference (MCID)
Epidural Blood Patch for Chronic Daily
Headache with Postural Component: A Case
Report and the Review of Published Cases
Authors: Ahmed Shihab
Published: March 2021

Post dural puncture headache (PDPH) can be observed after any trauma to
the dura. The hallmark of PDPH is an increasing headache when assuming
the upright position and improvement with the supine position. Diagnosis
of PDPH is essentially based on history of dural puncture and clinical presentation. In most cases, if initial conservative therapies fail to provide the relief
of symptoms, an epidural blood patch is the therapy of choice.
Epidural blood patch is a safe and effective treatment for PDPH and routinely done for acute onset of postural headache after spinal or epidural anesthesia or analgesia.
Here, we report the successful treatment of chronic daily headache with a
postural component via an epidural blood patch one year after the onset.
We also review the literature pertinent to the use of epidural blood patch in
chronic daily headache patients with postural component.
Key words: Post-dural puncture headache, postural headache, chronic
daily headache, epidural blood patch
A Crisis in Chronic Pain Care: An Ethical Analysis.
Part Three: Toward an Integrative,
Multi-disciplinary Pain Medicine Built Around
the Needs of the Patient
Authors: Giordano James
Published: March 2021

A number of variables have contributed to the current crisis in chronic pain care and are affected by, and affect, the philosophies and politics that influence the socio-economic climate
of the American healthcare system. Thus, we posit that managing the crisis in chronic pain
care in the United States is contingent upon the development of a multi-focal healthcare
paradigm that more thoroughly enables and fortifies research, its translation (in education
and practice), and the implementation of, and support for, both the curative and healing approaches in medicine in general, and pain care specifically. These steps necessitate re-examination, if not revision of the health care system and its economics.
The ethical imperative to consider and prudently employ cutting-edge diagnostic and therapeutic technologies in pain medicine is obligatory. However, “supply side prudence” is of little value if “demand side accessibility” is lacking. Revisions to health insurance plans advocated by the in-coming administration seek to create uniformity in basic health care services
based upon re-assessment of the clinical effectiveness (versus merely cost) of treatments, including those that are “high tech.” These plans attempt to allow every patient a more complete ability to deliberatively work with physicians to access those services and resources that
maximize health functioning and goals. But even given these revisions, authentic pain care
must take into account the interactive contexts of the painient individual. The biopsychosocial
model of chronic pain management may have significant practical and ethical worth in this
regard. A system of pain treatment operating from a biopsychosocial perspective necessitates
integrative multi-disciplinarity. We propose a tiered, multi-disciplinary paradigm based upon
the differing needs of each specific patient. But establishing such a system does not guarantee access, and distribution of these services and resources requires economic support to ensure that capabilities are more broadly available (i.e., supplied), and afforded as needed and
wanted (i.e., demanded).
Toward this end, we posit the need to focus upon, and more fully integrate 1) education, 2)
multi-disciplinary care (including re-vivification of MPCs), 3) policies that allow financial subsidies that afford patients the latitude to access and utilize such expanded resources appropriately to meet identified medical needs, and 4) medico-legal initiatives and statutes that protect and enable patients and physicians. The proposed changes comport with a number of
ethical systems in that they support the basic deontic structure of the profession and allow
for a richer, more finely grained articulation of clinical and ethical responsibilities within the
scope of particular general, specialty, and sub-specialty practices.
Key words: Pain medicine, ethics, policy, integrative care, multi-disciplinary pain care
Acute Spinal Pain During an Attempted Lumbar
Epidural Blood Patch in Congenital Lumbar
Spinal Stenosis and Epidural Lipomatosis
Authors: Hooten W. Michael
Published: March 2021

Congenital lumbar spinal stenosis is an uncommon condition that is often asymptomatic in young adults. Herein, we document the first reported occurrence of
acute radicular back pain and associated congenital lumbar spinal stenosis in a
healthy 24-year-old woman undergoing an epidural blood patch for treatment of
a post-dural puncture headache related to an accidental dural puncture sustained
during placement of a labor epidural catheter.
The acute pain symptoms were elicited twice with injection of less than 1 mL of fluid into the epidural space during the fluoroscopically assisted epidural blood patch.
Subsequent magnetic resonance imaging of the lumbar spine demonstrated shortened pedicle length consistent with severe congenital lumbar spinal stenosis and
prominent epidural fat. We speculate that the transient increase in pressure within the epidural compartment following injection of a small amount of fluid could
have compressed neural structures resulting in severe radicular pain. The prominent
epidural fat could have prevented rapid disbursement of the injected fluid which
could have further served to propagate the pressure increase throughout the epidural compartment.
The unique radiographic features of congenital spinal stenosis could predispose
some patients with this unrecognized condition to develop acute pain upon injection of a small amount of fluid into the epidural compartment. Unrecognized congenital lumbar spinal stenosis is an important addition to the differential diagnosis
of acute radicular pain elicited during an epidural blood patch in previously asymptomatic patients.
Key words: Epidural blood patch, congenital spinal stenosis, epidural lipomatosis, acute spinal pain
The Utilization of Transcutaneous Oxygen
Pressures to Guide Decision-Making for
Spinal Cord Stimulation Implantation for
Inoperable Peripheral Vascular Disease: A
Report of Two Cases
Authors: Provenzano David A.
Published: March 2021

Spinal cord stimulation (SCS) may be helpful in treating pain and vascular insufficiency associated with inoperable peripheral vascular disease (PVD). Often decision-making regarding progression from trial to implantation is based
on subjective measures. Transcutaneous oxygen pressure, a measure of microcirculation and tissue perfusion, provides information on changes that
may occur in PVD patients that undergo SCS trials and may provide predictive information for patient outcomes. This article reports on 2 patients with
severe PVD in which transcutaneous oxygen pressures were measured during
the trial phase, guided progression to implantation, and were followed in the
postoperative period. Transcutaneous oxygen pressure values continued to
improve following permanent implantation. We provide a review on transcutaneous oxygen pressure monitoring, along with emphasis on the technical
aspects of transcutaneous oxygen pressure monitoring and its incorporation
into practice. The decision to implant a SCS should be based on not only subjective measures of improvement, but also objective measures of improvement in transcutaneous oxygen pressure. Additional research is warranted to
develop transcutaneous oxygen pressure predictive indices to assist in the selection of patients for progression to permanent implantation.
Key words: Spinal cord stimulation, peripheral vascular disease, transcutaneous oxygen pressure monitoring.
Prevalence of Side Effects of Prolonged Low or
Moderate Dose Opioid Therapy with Concomitant
Benzodiazepine and/or Antidepressant Therapy in
Chronic Non-Cancer Pain
Authors: Manchikanti Laxmaiah
Published: March 2021

Background: Opioid use in the management of chronic pain is widespread in chronic pain
settings. Opioid prescriptions for non-cancer pain and overall opioid sales have been soaring
with the increasing nonmedical use of opioids in the United States. Prolonged use of high dose
opioids has been associated with adverse consequences including tolerance, abuse, addiction,
hyperalgesia, hormonal effects, and immunosuppression.
Studies of high dose therapy have shown pain relief with a 30% decrease in the intensity of pain
and that only 44% of the patients continue the treatment between 7 and 24 months. However,
there is no data available on the prevalence of side effects associated with low or moderate dose
opioid use in chronic non-cancer pain when administered in conjunction with interventional
techniques.
Objective: To evaluate the prevalence of side effects, of low or moderate dose opioid therapy
with or without benzodiazepines, antidepressants, and their combinations.
Methods: The evaluation was conducted by interviewing 1,000 patients on stable doses of
opioids, with or without benzodiazepines, antidepressants, and their combinations. Patients were
categorized into 4 groups with Group 1 receiving opioids only (n = 143), Group 2 receiving opioids
and benzodiazepines (n = 159), Group 3 receiving opioids and antidepressants (n = 113), and
Group 4 received opioids, benzodiazepines, and antidepressants (n = 118).
Results: Inclusion criteria was met in 533 patients receiving opioid therapy for longer than 6
months. The incidence of side effects in Group 1 was 18%, in Group 2 was 8%, in Group 3 was 17%,
and in Group 4 was 14%. The most frequent complications were in patients receiving methadone
(52%) followed by oxycodone (41%) and morphine (36%). Patients receiving hydrocodone had
the least incidences of side effects with 7.5%. There were no significant differences noted based
on the duration of therapy, age of the patient, and gender. Severe side effects accounted for only
14 of 137 instances.
Limitations: Limitations of this study include the inability to incorporate multiple other drugs due
to complicated nature with multiple groups and data collection and analysis. The other limitation
is that the proportion of patients receiving methadone, oxycodone, morphine, and propoxyphene
was low compared to hydrocodone with 77% of the patients.
Conclusion: Moderate or low dose opioid therapy in conjunction with or without benzodiazepines,
antidepressants, or in combinations are associated with minor side effects.
Key words: Opioids, benzodiazepines, antidepressants, chronic non-cancer pain, abuse, side
effects
Systematic Review of Cervical Discography as a
Diagnostic Test for Chronic Spinal Pain
Authors: Manchikanti Laxmaiah
Published: March 2021

Background: Chronic neck pain represents a significant public health problem. Despite
high prevalence rates, there is a lack of consensus regarding the causes or treatments
for this condition. Based on controlled evaluations, the cervical intervertebral discs, facet
joints, and atlantoaxial joints have all been implicated as pain generators. Cervical provocation discography, which includes disc stimulation and morphological evaluation, is
often used to distinguish a painful disc from other potential sources of pain. Yet in the
absence of validation and controlled outcome studies, the procedure remains mired in
controversy.
Study Design: A systematic review of the cervical discography literature.
Objective: To evaluate the validity and usefulness of cervical provocation discography in
managing and diagnosing discogenic pain by means of a systematic review.
Methods: Following a comprehensive search of the literature, selected studies were
subjected to a modified Agency for Healthcare Research and Quality (AHRQ) diagnostic
accuracy evaluation. Qualitative analysis was conducted using 5 levels of evidence, ranging from Level I to III with 3 subcategories in Level II. The rating scheme was modified to
evaluate the diagnostic accuracy.
Results: A systematic review of the literature demonstrated that cervical discography
plays a significant role in selecting surgical candidates and improving outcomes, despite
concerns regarding the false-positive rate, lack of standardization, and assorted potential
confounding factors. Based on the studies utilizing the International Association for the
Study of Pain (IASP) criteria, the data show a prevalence rate ranging between 16% and
20%. Based on the 3 studies that utilized IASP criteria during the performance of cervical
discography, the evidence derived from studies evaluating the diagnostic validity of the
procedure, the indicated level of evidence is Level II-2 based on modified U.S. Preventive
Services Task Force (USPSTF) criteria.
Limitations: Limitations include a paucity of literature, poor methodologic quality, and
very few studies performed utilizing IASP criteria.
Conclusion: Cervical discography performed according to the IASP criteria may be a
useful tool for evaluating chronic cervical pain, without disc herniation or radiculitis.
Based on a modified AHRQ accuracy evaluation and USPSTF level of evidence criteria,
this systematic review indicates the strength of evidence as Level II-2 for diagnostic accuracy of cervical discography.
Key words: Neck pain, headache, cervical discogenic pain, cervical intervertebral disc,
cervical provocation discography, false-positive rates, diagnostic accuracy, outcomes, cervical facet joint pain, controlled diagnostic blocks
Systematic Review of Percutaneous
Adhesiolysis and Management of Chronic Low
Back Pain in Post Lumbar Surgery Syndrome
Authors: Epter Richard
Published: March 2021

Background: Post lumbar surgery syndrome or failed back surgery syndrome with persistent
pain continues to increase over the years. The speculated causes of post lumbar laminectomy syndrome include acquired stenosis, epidural fibrosis, arachnoiditis, radiculopathy, and recurrent disc
herniation. Epidural fibrosis may account for as much as 20% to 36% of all cases of failed back
surgery syndrome. Percutaneous epidural adhesiolysis has been employed in interventional pain
management in the treatment of chronic, refractory low back and lower extremity pain after back
surgery.
Study Design: A systematic review of randomized trials and observational studies.
Objective: To evaluate the effectiveness of percutaneous adhesiolysis in managing chronic low
back and lower extremity pain due to post lumbar surgery syndrome.
Methods: A comprehensive literature search was conducted utilizing electronic databases, as
well as systematic reviews and cross references from 1966 through December 2008.
The quality of individual articles used in this analysis was assessed by modified Cochrane review
criteria for randomized trials and the Agency for Healthcare Research and Quality (AHRQ) criteria for assessment of observational studies.
Clinical relevance was evaluated using 5 questions according to the criteria recommended by the
Cochrane Review Back Group.
Analysis was conducted using 5 levels of evidence, ranging from Level I to III, with 3 subcategories in Level II.
Outcome Parameters: The primary outcome measure was pain relief (short-term relief of
at least 6 months and long-term relief of more than 6 months). Secondary outcome measures
were improvement in functional status, psychological status, return to work, and change in opioid intake.
Results: Of the 13 studies considered for inclusion, 3 randomized trials and 4 observational
studies met the inclusion criteria for methodologic quality assessment and evidence synthesis
based on methodologic quality scores of 50 or more. Evidence of percutaneous adhesiolysis in
the management of chronic low back pain in post-lumbar surgery syndrome is Level I to Level II1, with evidence derived from 3 randomized trials.
Limitations: There is a paucity of efficacy and pragmatic trials. No trials have been published
after 2006.
Conclusion: The indicated level of evidence for percutaneous adhesiolysis is Level I or II-1
based on the US Preventative Services Task Force (USPSTF) criteria.
Key words: Chronic low back pain, post lumbar surgery syndrome, post surgery syndrome,
failed back surgery syndrome, spinal stenosis, epidural fibrosis, interventional techniques, percutaneous adhesiolysis, hypertonic saline neurolysis
Evidence-Based Medicine, Systematic
Reviews, and Guidelines in Interventional
Pain Management: Part 5. Diagnostic
Accuracy Studies
Authors: Manchikanti Laxmaiah
Published: March 2021

Diagnosis is a critical component of health care. The world of diagnostic tests is highly dynamic. New tests are developed at a fast pace and technology of existing tests is
continuously being improved. However, clinicians, policy makers, and patients routinely
face a range of questions regarding diagnostic tests. Well designed diagnostic test accuracy studies can help in making these decisions, provided that they transparently and
fully report their participants, tests, methods, and results (as facilitated). For example,
by the standards for the reporting of diagnostic accuracy studies (STARD) statement.
Exaggerated and biased results from poorly designed and reported diagnostic test
studies can trigger their premature dissemination and lead physicians into making incorrect treatment decisions. Thus, a diagnostic test is useful only to the extent that it
distinguishes between conditions or disorders that might otherwise be confused. While
almost any test can differentiate healthy persons from severely affected ones, appropriate diagnostic tests should differentiate mild and moderate forms of disease.
Shortcomings in a study design and interpretation can affect estimates of diagnostic
accuracy. Thus, quality diagnostic studies are essential in medicine in general and interventional pain management in particular. The STARD initiative was developed to improve the accuracy and completeness in the reporting of studies of diagnostic accuracy and provide guidance to assist in reducing the potential for bias in the study and to
evaluate a study’s generalizability.
In the practice of interventional pain management, in addition to diagnostic tests which
include laboratory tests, imaging tests, and physical examination, diagnostic interventional techniques are crucial. Interventional techniques as a diagnostic tool in painful
conditions is important due to multiple challenging clinical situations, which include
the purely subjective nature of pain and underdetermined and uncertain pathophysiology in most painful spinal conditions. Precision diagnostic blocks are used to clarify
these challenging clinical situations in order to determine the pathophysiology of clinical pain, the site of nociception, and the pathway of afferent neural signals.
Part 5 of evidence-based medicine (EBM) in interventional pain management describes
the various aspects of diagnostic accuracy studies.
Key words: Evidence-based medicine, diagnostic studies, systematic reviews, randomized trials, interventional pain management, standards for the reporting of diagnostic accuracy studies (STARD)
Systematic Review of Lumbar Discography as a
Diagnostic Test for Chronic Low Back Pain
Authors: Manchikanti Laxmaiah
Published: March 2021

Background: The intervertebral disc has been implicated as an etiology of chronic lumbar
spine pain based on clinical, basic science, and epidemiological research. However, there is lack
of consensus regarding the diagnosis and treatment of intervertebral disc disorders. Based on
controlled evaluations, the lumbar intervertebral discs have been shown to be sources of chronic back pain without disc herniation in 26% to 39%. Lumbar provocation discography, which
includes disc stimulation and morphological evaluation, is often used to distinguish a painful
disc from other potential sources of pain. Despite the extensive literature, controversy continues
about provocation lumbar discography.
Study Design: A systematic review of the lumbar provocation discography literature.
Objectives: To systematically assess the diagnostic accuracy of lumbar discography.
Methods: A systematic review of the literature was performed to assess the diagnostic accuracy of lumbar discography with respect to chronic low back pain. Study inclusion/exclusion criteria were based on International Association for the Study of Pain (IASP) standards with pain
provocation and determination of controlled discs. Selected studies were then subjected to a
rating instrument for diagnostic accuracy studies. Specific data were then culled from these
studies and tabulated. Quality of evidence was assessed using modified Agency for Healthcare
Research and Quality (AHRQ) diagnostic accuracy evaluation. Studies meeting methodologic
quality criteria scores of 50 or higher were included in the assessment of the level of evidence.
Qualitative analysis was conducted using 5 levels of evidence, ranging from Level I to III, with 3
subcategories in Level II. The rating scheme was modified to evaluate the diagnostic accuracy.
Results: Based on a modified U.S. Preventive Services Task Force (USPSTF) level of evidence criteria, this systematic review indicates the strength of evidence as Level II-2 for the diagnostic accuracy of lumbar provocation discography utilizing IASP criteria.
Limitations: Limitations include a paucity of literature, poor methodologic quality, and very
few studies performed utilizing IASP criteria.
Conclusion: Based on the current systematic review, lumbar provocation discography performed according to the IASP criteria with control disc (s) with minimum pain intensity of 7 of
10, or at least 70% reproduction of worst pain (i.e. worst spontaneous pain of 7 = 7 x 70% =
5) may be a useful tool for evaluating chronic lumbar discogenic pain. Discography is an important imaging and pain evaluation tool in identifying a subset of patients with chronic low back
pain secondary to intervertebral disc disorders.
Key words: Chronic low back pain, lumbar intervertebral disc, lumbar discography, provocation discography, pain generator, false-positives, diagnostic accuracy, sensitivity, specificity
Systematic Review of Percutaneous Lumbar
Mechanical Disc Decompression Utilizing
Dekompressor
Authors: Singh Vijay
Published: March 2021

Background: In recent years, a number of minimally invasive nuclear decompression techniques for lumbar disc prolapse, protrusion, and/or herniation have been introduced, including
the Dekompressor® a device utilizing an Archimedes screw. The primary goal of the surgical treatment of nerve root compression from a disc protrusion continues to be the relief of compression
by removing the herniated nuclear material with open discectomy. However, poor results have
been reported for contained disc herniations with open surgical interventions. The results with
several alternative techniques including the Dekompressor, automated percutaneous discectomy,
and laser discectomy have been described, but are not convincing. There is a paucity of evidence
for all decompression techniques.
Study Design: A systematic review of the mechanical disc decompression with Dekompressor literature.
Objective: The objective of this systematic review is to evaluate the clinical effectiveness of
the Dekompressor, a high rotation per minute device utilizing an Archimedes screw, used in mechanical lumbar disc decompression.
Methods: The literature search was conducted utilizing a comprehensive strategy for mechanical
disc decompression utilizing the Dekompressor. A literature search was conducted using only English language literature in a comprehensive search of databases including PubMed, EMBASE, the
Cochrane Library, along with systematic reviews, and cross-references from reviews, systematic reviews, and individual articles. The quality of the manuscripts included was evaluated according to
Cochrane review criteria for randomized controlled trials (RCTs), and for observational studies with
the criteria developed by the Agency for Healthcare Research and Quality (AHRQ).
The level of evidence developed by the United States Preventive Services Task Force (USPSTF)
was utilized in this review. The evidence was classified as Level I, II, or III with 3 subcategories in
Level II for a total of 5 levels of evidence.
Outcome Measures: Pain relief was the primary outcome measure. Other outcome measures were
functional improvement, improvement of psychological status, opioid intake, and return to work.
Short-term effectiveness was defined as one year or less, whereas, long-term effectiveness was
defined as greater than one year.
Results: Based on USPSTF criteria the indicated level of evidence for the mechanical high RPM
device or Dekompressor is Level III for short- and long-term relief.
Limitations: Lack of literature, both randomized and observational.
Conclusion: This systematic review illustrates Level III evidence for mechanical percutaneous
disc decompression procedures with the high RPM device or Dekompressor.
Key words: Intervertebral disc disease, chronic low back pain, mechanical disc decompression,
disc protrusion, disc extrusion, radiculitis, and mechanical high RPM device, Dekompressor
Successful Treatment of Refractory Pudendal
Neuralgia with Pulsed Radiofrequency
Authors: Rhame Ellen E.
Published: March 2021

Pudendal neuralgia (PN) involves severe, sharp pain along the course of the pudendal
nerve, often aggravated with sitting. Current therapies include medication management,
nerve blocks, decompression surgery, and neuromodulation. The ideal management for
PN has not been determined.
We present a case of a female with 1.5 years of sharp, burning pain of the left gluteal
and perineal regions. She could not sit for longer than 10 to 15 minutes. Sacroiliac
joint, epidural, and piriformis injections did not improve her pain. She had tried physical
therapy, occupational therapy, massage, and acupuncture but the pain persisted.
Medication treatment with oxycodone-acetaminophen, extended release morphine
sulfate, amitriptyline, and gabapentin provided only minor relief and she had failed other
multianalgesic therapy. She had been unable to work at her desk job for over a year. She
had a positive response to 2 diagnostic pudendal nerve blocks with lidocaine that provided
pain relief for several hours. This patient elected to undergo pulsed radiofrequency (PRF)
of the left pudendal nerve in hopes of achieving a longer duration and improved pain
relief. PRF was carried out at a frequency of 2 Hz and a pulse width of 20 milliseconds
for a duration of 120 seconds at 42 degrees Celsius. After the procedure she reported
tolerating sitting for 4 to 5 hours. Her multianalgesic therapy was successfully weaned.
At 5 months follow-up she felt motivated to return to work. One and a half years after
the procedure the patient is only taking oxycodone-acetaminophen for pain relief and
still has good sitting tolerance. There were no procedure-related complications.
To our knowledge PRF for the treatment of PN has not been reported elsewhere in
the literature. PRF is a relatively new procedure and is felt to be safer than continuous
radiofrequency. Current literature suggests that PRF delivers an electromagnetic field,
which modifies neuro-cellular function with minimal cellular destruction. We conclude
that PRF of the pudendal nerve offers promise as a potential treatment of PN that is
refractory to conservative therapy.
Key words: pudendal neuralgia, pulsed radiofrequency, pudendal nerve,
neuromodulation
Opioid Induced Hyperalgesia: Clinical
Implications for the Pain Practitioner
Authors: Silverman Sanford M.
Published: March 2021

Opioids have been and continue to be used for the treatment of chronic pain. Evidence
supports the notion that opioids can be safely administered in patients with chronic pain
without the development of addiction or chemical dependency. However, over the past
several years, concerns have arisen with respect to administration of opioids for the treatment
of chronic pain, particularly non-cancer pain. Many of these involve legal issues with respect
to diversion and prescription opioid abuse. Amongst these, opioid induced hyperalgesia (OIH)
is becoming more prevalent as the population receiving opioids for chronic pain increases.
OIH is a recognized complication of opioid therapy. It is a pro-nocioceptive process which
is related to, but different from, tolerance. This focused review will elaborate on the
neurobiological mechanisms of OIH as well as summarize the pre-clinical and clinical studies
supporting the existence of OIH. In particular, the role of the excitatory neurotransmitter, Nmethyl-D-aspartate appears to play a central, but not the only, role in OIH. Other mechanisms
of OIH include the role of spinal dynorphins and descending facilitation from the rostral
ventromedial medulla. The links between pain, tolerance, and OIH will be discussed with
respect to their common neurobiology.
Practical considerations for diagnosis and treatment for OIH will be discussed. It is crucial for
the pain specialist to differentiate amongst clinically worsening pain, tolerance, and OIH since
the treatment of these conditions differ. Tolerance is a necessary condition for OIH but the
converse is not necessarily true.
Office-based detoxification, reduction of opioid dose, opioid rotation, and the use of specific
NMDA receptor antagonists are all viable treatment options for OIH. The role of sublingual
buprenorphine appears to be an attractive, simple option for the treatment of OIH and is
particularly advantageous for a busy interventional pain practice.
Key words: Opioid hyperalgesia, hyperalgesia, tolerance, NMDA receptor antagonists,
NMDA receptor induced hyperalgesia, spinal dynorphin induced hyperalgesia, descending
facilitation and hyperalgesia, buprenorphine and hyperalgesia, opioid detoxification, officebased detoxification, complications of opioid therapy
Accuracy of Diagnostic Lumbar Facet Joint
Nerve Blocks: A 2-Year Follow-Up of 152 Patients
Diagnosed with Controlled Diagnostic Blocks
Authors: Manchikanti Laxmaiah
Published: March 2021

Background: Lumbar facet joint pain is diagnosed by controlled diagnostic blocks. The accuracy
of controlled diagnostic blocks has been demonstrated in multiple studies and confirmed in
systematic reviews. Controlled diagnostic studies have shown an overall prevalence of lumbar
facet joint pain in 31% of the patients with chronic low back pain without disc displacement or
radiculitis, with an overall false-positive rate of 30% using a single diagnostic block.
Study Design: An observational report of outcomes assessment.
Setting: An interventional pain management practice setting in the United States.
Objective: To determine the accuracy of controlled diagnostic blocks in managing lumbar
facet joint pain at the end of 2 years.
Methods: This study included 152 patients diagnosed with lumbar facet joint pain using
controlled diagnostic blocks. The inclusion criteria was based on a positive response to
diagnostic controlled comparative local anesthetic lumbar facet joint blocks. The treatment
included therapeutic lumbar facet joint nerve blocks.
Outcome Measures: The sustained diagnosis of lumbar facet joint pain at the end of one
year and 2 years based on pain relief and functional status improvement.
Results: At the end of one year 93% of the patients and at the end of 2 years 89.5% of the
patients were considered to have lumbar facet joint pain.
Limitations: The study is limited by its observational nature.
Conclusion: Controlled diagnostic lumbar facet joint nerve blocks are valid utilizing the criteria
of 80% pain relief and the ability to perform previously painful movements, with sustained
diagnosis of lumbar facet joint pain in at least 89.5% of the patients at the end of a 2-year
follow-up period.
Key words: Chronic low back pain, lumbar facet or zygapophysial joint pain, facet joint
nerve or medial branch blocks, controlled local anesthetic blocks, construct validity, diagnostic
studies, diagnostic accuracy
Occipital Neurostimulation-Induced Muscle
Spasms: Implications for Lead Placement
Authors: Hayek Salim M
Published: March 2021

Background: For many headache types, occipital peripheral nerve stimulation (ONS)
provides significant relief of chronic, frequent, and severe headaches. Though rarely reported,
ONS may cause painful muscle spasms that make stimulator use impractical. The classic
description of the technique advocates placement of the leads transversely at the level of the
arch of C1 or at C1-2. At that level, the greater occipital nerve (GON) infrequently pierces the
superficial fascia of the neck muscles to become superficial. However, important anatomic
variability exists.
Objective: To report placement of leads higher at the nuchal line rather than the classically
recommended C1 level to avoid ONS-induced muscle spasm.
Methods: Four interventional pain physicians independently revised ONS leads due to
painful muscle stimulation. Five case reports of surgical ONS lead revision for management of
ONS-induced muscle spasms are described and discussed.
Results: Placement of peripheral neurostimulator leads at or above the nuchal line in these
5 cases provided good paresthesiae without causing neck muscle spasm.
Conclusion: Lead placement at the level of C1 or C1-2 may cause some patients to have
intolerable neck/occipital spasm during neurostimulation. This is the first known published
report of technical variation in the location of lead placement, at the nuchal line in a transverse
fashion, for ONS. Placing ONS leads at the level of the occipital protuberance appears to
eliminate ONS-induced muscle spasm while allowing good paresthesia coverage.
Limitations: Stimulation parameters vary, thus posting parameters may be misleading as
muscle spasms occurred despite multiple reprogramming attempts and were a function of
lead position, not program settings.
Key words: Occipital nerve stimulator, peripheral neurostimulation, muscle spasm,
complication, interventional pain management, cephalgia, headache, migraine, occipital
neuralgia, greater occipital nerve
Pain in Nursing Home Residents and
Correlation with Neuropsychiatric Disorders
Authors: Walid M. Sami
Published: March 2021

Background: Pain is a common problem in older age and strongly interacts with neuropsychiatric
disorders. In this paper we studied the prevalence of pain and the connection between pain and neuropsychiatric comorbidities among older nursing home residents.
Objective: To determine if data provided in 2004 National Nursing Home Sturvey supports connection between pain and neuropsychiatric comorbidities among older nursing home residents.
Setting: Medical university.
Design: Retrospective study of published reports
Methods: We used the results of the 2004 National Nursing Home Survey (NNHS) to determine the
rates and correlations of pain parameters with the main neurodegenerative and psychiatric diagnoses
in residents over 65 years of age including Alzheimer’s and Picks dementia, schizophrenia, depression,
bipolar disease, anxiety, and obsessive-compulsive disorder.
Results: Pain was reported by 22% of residents over 65 years of age. Patients with anxiety or depression had the highest prevalence of pain, 29.4% and 24.4%, respectively. Patients with dementia had the
lowest rate of reported pain, 14.5%. All neurodegenerative and psychiatric diagnoses had significant
correlations (P = 0.000) with pain rate, however, only anxiety (r = 0.056) and depression (r=0.025) positively correlated with the presence of pain. There were clear differences in the highest levels of reported
pain in different neurodegenerative and psychiatric groups. We created the Disease-Specific Pain Intensity Scale (DSPI Scale) which can be calculated for each diagnostic entity. The DSPI was highest in patients
with obsessive-compulsive disorder (721) and lowest in patients with bipolar disease (358). The average
value of this scale in nursing home residents who reported pain in the last 7 days was 488.
Limitations: The overwhelming majority of patients had chronic somatic diseases that were not included in the analysis and could skew the results. In addition, pain perception could be affected by prescribed
medications which were not taken into consideration. Moreover, neurodegenerative and psychiatric disorders could interact among each other and overlapped cases were not regarded in our research. Finally, the new instrument created for evaluating the spectrum of highest pain intensities in a group of patients with a specific diagnosis requires validation. It is a unidimentional scale that does not incorporate
the length of time a person has experienced pain, an important parameter in pain chronicity.
Conclusion: It is important when assessing pain to consider the patient’s neuropsychiatric status and especially communication abilities. The information above helps understand the variances in pain parameters
in neuropsychiatric patients and may ultimately lead to better pain management in these difficult patients.
Key words: Pain, neurodegenerative, psychiatric, nursing home
Analysis of Growth of Interventional Techniques in
Managing Chronic Pain in the Medicare Population:
A 10-Year Evaluation from 1997 to 2006
Authors: Manchikanti Laxmaiah
Published: March 2021

Background: Recent reports of the United States Government Accountability Office (GAO),
the Medicare Payment Advisory Commission (MedPAC), and the Office of Inspector General
(OIG) expressed significant concern with overall fiscal sustainability of Medicare and exponential
increase in costs for interventional pain management techniques.
Interventional pain management (IPM) is an evolving specialty amenable to multiple influences.
Evaluation and isolation of appropriate factors for increasing growth patterns have not been performed.
Study Design: Analysis of the growth of interventional techniques in managing chronic pain
in Medicare beneficiaries from 1997 to 2006.
Objective: To evaluate the use of all interventional techniques.
Methods: The standard 5% national sample of the CMS carrier claim record data for 1997,
2002, and 2006 was utilized. This data set provides information on Medicare enrollees in the feefor-service Medicare program. Current procedural technology (CPT) codes for 1997, 2002, and
2006 were used to identify the number of procedures performed each year, and trends in expenditures.
Results: Interventional techniques increased significantly in Medicare beneficiaries from 1997
to 2006. Overall, there was an increase of 137% in patients utilizing IPM services with an increase of 197% in IPM services, per 100,000 Medicare beneficiaries. The majority of the increases were attributed to exponential growth in the performance of facet joint interventions.
There was a 13.9-fold difference in the increase between the state with the lowest rate and the state
with the highest rate in utilization patterns of interventional techniques (California 37% vs. Connecticut 514%), with an 11.6-fold difference between Florida and California (431% vs. 37% increase). In
2006, Florida showed a 12.7-fold difference compared to Hawaii with the lowest utilization rate.
Hospital outpatient department (HOPD) expenses constituted the highest increase with fewer
patients treated either in an ambulatory surgery center (ASC) or in-office setting. Overall HOPD
payments constituted 5% of total 2006 Medicare payments, in contrast to 57% of total IPM
payments, an 11.4-fold difference.
Limitations: The limitations of this study include a lack of inclusion of Medicare participants
in Medicare Advantage plans and potential documentation, coding, and billing errors.
Conclusion: This study shows an overall increase of IPM services of 197% compared to an increase of 137% in patients utilizing IPM services from 1997 to 2006.
Key words: Interventional techniques, interventional pain management, facet joint injections,
epidural steroid injections, sacroiliac joint injections, chronic pain, chronic spinal pain, ambulatory surgery center (ASC), hospital outpatient department (HOPD)
Cross Talk: A New Method for Peripheral Nerve
Stimulation. An Observational Report with
Cadaveric Verification
Authors: Falco Frank
Published: March 2021

Background: Relief of regional, non-appendicular pain, particularly low back pain, through
spinal cord stimulation (SCS) has proven challenging. Recently, peripheral nerve stimulation
(PNS), also known as peripheral nerve field stimulation (PNFS) depending on the stimulation
area, has demonstrated efficacy for the treatment of well-localized, small areas of pain involving
the abdomen, inguinal region, pelvis, face, occipital area, and low back. More widespread
application of peripheral nerve stimulation has been limited by its narrow field of coverage in a
larger group of patients with diffuse or poorly localized pain.
Objectives: To determine if cross talk (the creation of an electrical circuit and therefore electrical
stimulation between separate subcutaneously placed PNS leads [i.e. inter-lead stimulation]) was
clinically possible across large painful areas, assess the breadth of stimulation coverage via cross
talk, evaluate the clinical efficacy of peripheral nerve stimulation cross talk (PNSCT), and confirm
the existence of cross talk across a large area in a cadaveric model.
Study Design: Case series observational report and cadaveric experimentation.
Setting: A private, comprehensive interventional pain management practice with pain
medicine fellowship training in the United States.
Methods: Eighteen consecutive patients with non-appendicular, regional pain were included in
the study. Data collection for the implanted patients included the presence or absence of stimulation
between the PNS leads, stimulation tolerability, stimulation region, lead orientation, lead montage,
inter-lead distance, and pain relief from PNSCT compared to PNS without cross talk.
A cadaveric analysis was performed to determine the presence or absence of an electrical circuit
with 2 subcutaneously PNS leads to confirm or refute the existence of electrical stimulation from
on lead to the other within subcutaneous fat with the leads placed at a significant distance apart
from one another.
Results: All 18 patients experienced significant pain relief, reduction of pain medication, and
functional improvement. Cadaveric experimentation confirmed the presence of an electrical
circuit with PNS leads placed at a distance far apart from one another and verified that interlead stimulation (cross talk) does occur in subcutaneous fat over a great distance.
Limitations: This study was limited by its small sample size, and the short-term follow-up
after implantation.
Conclusions: The use of the PNSCT technique allows for significant analgesia for large painful
areas that have been poorly captured using traditional SCS techniques and not considered as an
option with the current application of peripheral nerve stimulation.
Key words: Peripheral nerve stimulation, peripheral nerve field stimulation, cross talk, spinal
cord stimulation, neuromodulation, low back pain, failed back surgery syndrome, abdominal
pain, neck pain, post herpetic neuralgia, occipital headaches
Vertebral Osteomyelitis Following
Vertebroplasty: Is Acne a Potential
Contraindication and Are Prophylactic
Antibiotics Mandatory Prior to Vertebroplasty?
Authors: Syed Mubin I.
Published: March 2021

We present a case of vertebral osteomyelitis following vertebroplasty in a patient with
acne of the back. Vertebral biopsy revealed Corynebacterium species and blood cultures
were positive for Propionibacterium species.
The patient did not respond to long-term intravenous antibiotics and required vertebral
corpectomy and debridement with instrumentation. Interventionalists should be able
to recognize acne of the back and consider this as a potential contraindication to
vertebroplasty.
Prophylactic antibiotics should be considered in all patients prior to vertebroplasty since
subepidermal organisms are not eliminated with the standard skin prep.
Key words: Vertebroplasty, complication, vertebral osteomylitis, acne