bluuebunny/crossref_metadata_2025 huggingface dataset:
A Comparative Effectiveness Evaluation
of Percutaneous Adhesiolysis and Epidural
Steroid Injections in Managing Lumbar Post
Surgery Syndrome: A Randomized, Equivalence
Controlled Trial
Authors: Manchikanti Laxmaiah
Published: March 2021

Background: Speculated causes of post lumbar surgery syndrome include epidural fibrosis, acquired
stenosis, and facet joint pain among other causes. Even though fluoroscopically directed caudal
epidural injections and facet joint interventions are effective in some patients, others continue to suffer
with chronic persistent pain. Percutaneous adhesiolysis with target delivery of medications has been
demonstrated to be effective in these patients. However, the evidence for percutaneous adhesiolysis in
managing post surgery syndrome has been questioned, coupled with a paucity of controlled trials.
Study Design: A randomized, equivalence, controlled trial.
Setting: An interventional pain management practice, a specialty referral center, a private practice
setting in the United States.
Objectives: To evaluate the effectiveness of percutaneous epidural adhesiolysis in patients
with chronic low back and lower extremity pain in post surgery syndrome and compare with
fluoroscopically directed caudal epidural steroid injections.
Methods: Patients were randomly assigned to one of 2 groups: Group I (60 patients) receiving
caudal epidural injections with catheterization up to S3 with local anesthetic, steroids, and
0.9% sodium chloride solution serving as the control group, and Group II (60 patients) receiving
percutaneous adhesiolysis with targeted delivery of lidocaine, 10% hypertonic sodium chloride
solution, and non-particulate Betamethasone serving as the intervention group. Randomization
was performed by computer-generated random allocation sequence by simple randomization.
Outcomes Assessment: Multiple outcome measures were utilized including the Numeric
Rating Scale (NRS), the Oswestry Disability Index 2.0 (ODI), employment status, and opioid intake
with assessment at 3, 6, and 12 months post treatment.
Significant pain relief was described as 50% or more, whereas significant improvement in the
disability score was defined as a reduction of 40% or more.
Results: Significant pain relief (≥ 50%) and functional status improvement was recorded in 73%
of patients in Group II versus 12% in Group I (P < 0.001). The average procedures per year were
3.5 with an average total relief of 42 out of 52 weeks in Group II and 2.2 procedures with total
relief per year of 13 weeks in Group I (P < 0.001).
Limitations: The results of this study are limited by potentially inadequate double blinding, by
the lack of a placebo group, and the preliminary report of one-year follow-up.
Conclusions: Percutaneous adhesiolysis in chronic function-limiting, recalcitrant low back pain
in post lumbar surgery syndrome demonstrated effectiveness in 73% of the patients.
Key words: Post lumbar surgery syndrome, post lumbar laminectomy syndrome, chronic low
back pain, epidural adhesions, epidural steroid injections, percutaneous adhesiolysis, epidural
fibrosis, spinal stenosis, randomized trial, comparative effectiveness
A Medical-Legal Review Regarding the
Standard of Care for Epidural Injections, with
Particular Reference to a Closed Case
Authors: Helm Standiford
Published: March 2021

Interventional pain management is an evolving field, with a primary focus on
the safety of the patient. One major source of risk to patients is intraarterial or
intraneural injections. Interventional pain physicians have considerable interest
in identifying techniques which avoid these complications. A recent article has
reviewed complications associated with interventional procedures and concluded
that the complications were due to deviation from a specific prescribed protocol.
One of the cases reviewed went to jury trial and the record of that case is in the
public domain. Two of the authors of the recent review were expert witnesses
in the trial. They provided conflicting testimony as to alleged violations of the
standard of care. Their criticisms also differed from a third criticism contained in
the article as well as the protocol being advocated in the article, thus contravening
the claim that there is one prescribed protocol which must be followed.
The definition of standard of care varies amongst jurisdictions, but is generally
defined as either that care which a reasonably well-trained physician in that
specialty would provide under similar circumstances or as what would constitute
reasonable medical care under the circumstances presented. Analysis of the case
which went to trial indicates that there is not one prescribed protocol which must
be followed; the definition of standard of care is broader than that. Interventional
pain management is an evolving field and the standard of care is broadly
defined.
Key words: Spine injection, complications, medical legal, standard of care,
transforaminal injections, compression fracture, low back pain
Intrathecal Catheter-Syringe Adaptor for
Short-Term Intrathecal Analgesia with an
Externalized Pump: A Case Report
Authors: WIlkes Denise
Published: March 2021

Background: In most patients, cancer pain is effectively treated with conservative medical
management consisting of oral and/or transdermal analgesics. Cancer patients tend to fail
conservative medical management near the end of their life expectancy, thus requiring alternative
routes of analgesia such as intravenous, epidural, or intrathecal. The intrathecal route provides
the most effective analgesia due to the close proximity of the opioid receptors in the spinal cord.
Though there are many techniques that exist for intrathecal drug delivery, complications can
limit effectiveness such as infection, bleeding, cerebrospinal fluid (CSF) leaks, post-dural puncture
headaches (PDPH), pump and/or catheter malfunctions, or limitations of technical expertise.
Therefore, an important goal in palliative cancer pain therapy is to use equipment that is going
to have the fewest number of complications and will be the most familiar to the health care
providers. We describe the combination of the Medtronic Indura 1P catheter, which has the least
catheter-related complications and can be used with any external drug infusion pump. These
are regular infusion pumps that the health care workers are familiar with so they can provide
excellent and efficient service to the patient.
Methods: In an operating room, the intrathecal catheter was placed using sterile technique under
fluoroscopic guidance. The epidural space was identified with loss of resistance technique. Then
the introducer needle (supplied in the Indura 1P catheter kit) was advanced until free-flowing CSF
was obtained. The spinal catheter was advanced into the intrathecal space through the introducer
needle to lumbar 2-3 level. The catheter was tunneled subcutaneously 10 cm lateral to the catheter
exit site. A syringe filling device was inserted into the catheter opening and was secured with silk
suture. A luer lock syringe was attached to the syringe filling device and CSF was aspirated. The
syringe filling device was capped and later attached to an external drug infusion pump.
Results: We report the successful use of the Medtronic Indura 1P, one piece intrathecal catheter,
connected to the external drug pump for a 3 week period in a patient with metastatic cervical
cancer for palliative pain control.
Limitations: Case report only.
Conclusion: This technique is simple to perform by pain specialists. The catheter modification
allows the use of the Medtronic intrathecal catheter with standard external drug infusion pumps.
This facilitates the patient’s care in the hospice setting.
Key words: Intrathecal drug delivery, palliative medicine, intrathecal analgesia, intrathecal
catheter complications, cancer pain, end of life pain control
Root Cause Analysis of Paraplegia Following
Transforaminal Epidural Steroid Injections: The
‘Unsafe’ Triangle
Authors: Glaser Scott E.
Published: March 2021

The utilization rate of transforaminal epidural steroid injections (TFESIs), an elective
diagnostic and therapeutic spinal procedure, has risen dramatically over the past
decade. In 2006 alone, greater than 300,000 thoracolumbar TFESIs were performed
on Medicare beneficiaries. Despite the purported superiority of the transforaminal
route, compared to other modes of epidural injection, TFESIs are associated with
potential hazards.
The artery of Adamkiewicz (ARM) might enter any mid thoracic, lower thoracic,
or lumbar foramen; the exact level, in a specific patient, will be unknown to the
proceduralist· The authors propose that the “safe triangle” approach to transforaminal
epidural injections is not safe (TFESIs).
Injury to the ARM can lead to paraplegia, independent of operator skill or adjuvant
safety initiatives (digital subtraction angiography, local anesthetic test dose). Injury to
the ARM is a “black swan” event. The authors believe that catastrophic injury may be
averted when performing TFESIs by avoiding the “un-safe,” superoanterior triangle
in the foramen and that transforaminal injections should be performed at the inferior
aspect of the foramen, known as Kambin’s triangle.
Key words: transforaminal, spinal cord, artery of Adamkiewicz, paraplegia, foramen,
radiculomedullary, root cause analysis, patient safety, medico-legal, black swan
Activated Microglia in Nociception
Authors: Smith Howard
Published: March 2021

Microglial cells appear to play a vital role in the initiation of certain
neuropathic pain states. In order to initiate neuropathic pain, microglia
need to be activated. Microglia activation in the spinal cord involves both
hypertrophy as well as hyperplasia, progressing through a hypertrophic
morphology, with thickened and retracted processes (observed within the
first 24 hours after nerve injury), and an increase in cell number (observed
around 2–3 days after nerve injury). There seems to be at least 5 major paths
to activate microglia. These 5 pathways will be discussed and are identified
by their main signaling mediator and/or receptor which include fractalkine,
interferon-gamma, monocyte chemoattractant protein-1, TLR4, and P2X4.
Thus, one or more of these mediators/pathways which lead to microglial
activation might contribute to neuropathic pain. A greater appreciation of
the roles of various mediators/paths which activate microglia might help lead
to future novel therapeutic targets in efforts to ameliorate severe symptoms
of neuropathic pain.
Key words: microglial cells, glia, C-fiber nociceptors, neuropathic pain,
hypertrophy, hyperplasia
Pulse Width Programming in Spinal Cord
Stimulation: A Clinical Study
Authors: Yearwood Thomas L.
Published: March 2021

Background: With advances in spinal cord stimulation (SCS) technology, particularly rechargeable
implantable, patients are now being offered a wider range of parameters to treat their pain. In
particular, pulse width (PW) programming ranges of rechargeable implantable pulse generators
now match that of radiofrequency systems (with programmability up to 1000µs). The intent of
the present study was to investigate the effects of varying PW in SCS.
Objective: To understand the effects of PW programming in spinal cord stimulation (SCS).
Design: Single-center, prospective, randomized, single-blind evaluation of the technical and
clinical outcomes of PW programming.
Setting: Acute, outpatient follow-up.
Methods: Subjects using fully-implanted SCS for > 3 months to treat chronic intractable low
back and/or leg pain. Programming of a wide range (50-1000μs) of programmed PW settings
using each patient’s otherwise unchanged ‘walk-in’ program.
Outcome Measures: Paresthesia thresholds (perception, maximum comfortable, discomfort),
paresthesia coverage and patient choice of tested programs.
Results: We found strength-duration parameters of chronaxie and rheobase to be 295 (242 –
326) μs and 2.5 (1.3 – 3.3) mA, respectively. The median PW of all patients’ ‘walk-out’ programs
was 400μs, approximately 48% higher than median chronaxie (P = 0.01), suggesting that chronaxie
may not relate to patient-preferred stimulation settings. We found that 7/19 patients selected new
PW programs, which significantly increased their paresthesia-pain overlap by 56% on average (P =
0.047). We estimated that 10/19 patients appeared to have greater paresthesia coverage, and 8/19
patients appeared to display a ‘caudal shift’ of paresthesia coverage with increased PW.
Limitations: Small number of patients.
Conclusions: Variable PW programming in SCS appears to have clinical value, demonstrated by
some patients improving their paresthesia-pain overlap, as well as the ability to increase and even
‘steer’ paresthesia coverage.
Key words: Spinal cord stimulation, pulse width, paresthesia, dermatome, implantable pulse
generator, neurostimulation, chronic pain, neuropathic, dorsal column, dorsal root, chronaxie.
A Treatment Option for Post-Injection
Sciatic Neuropathy: Transsacral Block with
Methylprednisolone
Authors: Eker H. Evren
Published: March 2021

Background: Accidental intraneural injection induced nerve injury is an iatrogenic tragedy and
intramuscular injection (IM) is the most common injury mechanism affecting the sciatic nerve. The
most frequent presentation of sciatic nerve injury includes radicular pain and paresthesia with almost
immediate onset of variable motor and sensory deficit.
Objectives: Intraneural injection is a common injury mechanism of the sciatic nerve and generates
neuropathic pain with inflammatory neuritis. Steroids inhibit the production of inflammatory mediators
and reduce ectopic discharges on damaged neural membranes. The results of transsacral steroid
injection on neuropathic pain in 5 patients with accidental sciatic nerve injury due to intraneural
injection were presented in this report.
Design: Report of 5 cases.
Description of Cases: Five patients, 32, 34, 45, 54 and 70 years old respectively, complaining of
severe neuropathic pain, paresthesia and progressive weakness of the lower extremity with difficulty
in walking secondary to gluteal injection were admitted to the clinic. The symptoms were resistant to
drug therapies. Electromyography disclosed axonal damage of the sciatic nerve. The initial examination
of the patients revealed a Numeric Rating Scale (NRS) of 10, 10, 9, 9, and 10 respectively.
Results: Diagnostic block was performed through the unilateral S1-S2-S3 sacral foramina with 22-
G spinal needle by 5 mL 1% lidocaine into each foramen. NRS scores decreased to 1, 2, 2, 2 and
1, respectively. One week later, the patients were administered 80 mg methylprednisolone with 1%
lidocaine in 15 mL solution shared equally in each foramen. The patients were checked one month
after therapeutic block and a full recovery was achieved in all patients.
Conclusion: The neuropathic pain due to accidental intraneural injection of the sciatic nerve would
be an acceptable indication for transsacral nerve block with corticosteroids in the treatment of sciatic
neuropathic pain symptoms.
Key words: Sciatic neuropathy, transsacral block, methylprednisolone
Trial Spinal Cord Stimulator Reimplantation
Following Lead Breakage after Third Birth
Authors: Naozumi Takeshima Naozumi Takeshima
Published: March 2021

Background: Many studies have reported lead migration and breakage as complications
of epidural spinal cord stimulation. In cases where rapid changes in physique such as those
caused by pregnancy are expected, it is unclear whether extra consideration regarding
possible adjustments and care to avoid complications such as lead breakage are required.
Objective: This article presents a case in which spinal cord stimulation was used to
manage these complications in a woman during the perinatal period.
Design: Case report
Setting: Pain management clinic
Methods: The patient was a 36-year-old female, approximate weight of 100 pounds,
and 5-foot 1 inch in height, whose chief complaint was lower back and bilateral leg pain.
The pain could not be alleviated by conservative therapies such as nerve blockade, oral
medications with non-steroidal anti-inflammatory drugs, antidepressants, anticonvulsants
or physical therapy. A spinal cord stimulator was implanted at another facility, which relieved
the pain. The patient subsequently had 2 vaginal births without any problems relating to
the stimulation sites, and both infants were healthy. She experienced lead breakage after
the third vaginal birth that led to the subsequent reimplantation procedure.
Results: The patient had 2 subsequent vaginal births following the initial implantation
with no problems related to the stimulation sites, and both infants were healthy. At age
34, following her third vaginal birth, the stimulator became ineffective and was removed.
The withdrawn lead wire was found to be broken in 2 places.
Limitations: A case report.
Conclusion: Pregnancy following implantation of a spinal cord stimulator might result in
lead breakage as abdominal girth increases. The present case exemplifies how pregnancy
following implantation of a spinal cord stimulator might cause lead breakage as abdominal
girth increases. Extra care is required to prevent lead breakage when anchors are fixed.
Key words: spinal cord stimulator, reimplantation, lead breakage, pregnancy
Radiation Exposure in Percutaneous Spinal
Cord Stimulation Mapping: A Preliminary
Report
Authors: Wininger Kevin L.
Published: March 2021

Background: The utilization of spinal cord stimulation (SCS) to treat intractable pain has
increased substantially in recent years. Integral to this therapy, the fluoroscope assists with
requisite mapping protocols during trialing procedures to identify topographical dermatomal
representations of spinal segments, and its use demands measurements of radiation exposure.
However, such data is not found in the literature.
Purpose: The aim of this study was to report on radiation exposure during percutaneous SCS
trialing procedures.
Design: An observational study.
Setting: A non-university out-patient Interventional Pain Management practice in the United
States.
Methods: Fluoroscopy time from 110 SCS trialing procedures performed in a non-university,
outpatient setting was studied retrospectively. Summary statistics were reported for all procedures
collectively, as well as for lead arrangement and location. The interventional spine team carried
out all procedural cases with the same mobile C-arm fluoroscopy system. Incident air kerma was
evaluated by simplistic modeling.
Results: Mean total fluoroscopy time was 133.4 s with a standard deviation of 84.8 s, and the
mean percentage of time allocated to pulsed fluoroscopy was 31.9%. Fluoroscopy time for the
most common lead arrangement/location, neural canal dual leads/low-thoracic (n=87), ranged
from 28.5 s to 387.4 s. Incident air kerma was 1.8–43.7 mGy.
Limitations: A preliminary report with a sample size of 110.
Conclusion: Various lead placement options are available to the spinal interventionalist to treat
pain with SCS. Our data set provides first steps to obtain benchmark reference estimates on
fluoroscopy times and radiation exposure during SCS trialing procedures/spinal segment mapping.
Fluoroscopy times for such interventions may be considerable when compared to more commonly
performed pain medicine procedures; however, skin injury is improbable.
Key words: Neuromodulation, radiation safety, fluoroscopy, dosimetry, dose reduction, health
physics
Application of X STOP Device in the Treatment
of Lumbar Spinal Stenosis
Authors: Yi Xiaobin
Published: March 2021

Low back pain is exceptionally ubiquitous, complex, and costly. Nevertheless, lumbar
spinal stenosis (LSS) with neurogenic intermittent claudication (NIC) is a frequent cause
of low back and lower extremity pain. Although the phenomena and pathophisiology
of lumbar spinal stenosis has been described for decades, therapeutic treatment
options remain considerably limited.
Current care consists of conservative measures including physical therapy, rest,
medications, and epidural steroid injection therapy or invasive surgical treatment
including laminectomy with or without fusion. Despite standard of care intervention,
many patients are often left inadequately treated and suffer from debilitating low back
and lower extremity pain as a result of lumbar spinal stenosis. Interspinous process
distraction (IPD) devices were originally described in the 1950s, but technological
advances, which have contributed to improved safety and efficacy, have rekindled an
interest in IPD implantation. By mimicking lumbar flexion at affected levels of stenosis,
it is thought these devices decompress neural structures within the neural foramina
and therefore provide pain relief. X-STOP is one such device that is currently approved
in the United States for the treatment of mild to moderate NIC resulting from LSS.
This manuscript presents a focused review of NIC and LSS and comprehensively
presents literature related to the use of the X-STOP IPD device.
Key words: Interspinous process distraction (IPD), X STOP, interspinous spacer (ISS),
lumbar spinal stenosis (LSS), neurogenic intermittent claudication (NIC), low back
pain, sciatica
In Response
Authors: Kapural Leonardo
Published: March 2021

Leonardo Kapural, MD, PhD
Hemorrhagic Gastritis and Duodenitis Following
Celiac Plexus Neurolysis
Authors: Pello Scott
Published: March 2021

Introduction: Neurolytic celiac plexus block is a well established intervention to palliate
pain, and it potentially improves quality of life in patients suffering from an upper abdominal
malignancy, specifically pancreatic cancer.
Methods: We describe a 61-year-old female with a history of pancreatic cancer, unexplained
transfusion dependent anemia with a normal recent upper endoscopy, and abdominal pain,
who had previously undergone gastrojejunostomy and a Roux-en-Y hepaticojejunostomy as
well as chemotherapy and radiation therapy. She suffered from intractable abdominal pain and
elected to undergo palliative celiac plexus neurolysis.
Results: The patient initially appeared to tolerate celiac plexus block well, however, 45 minutes
after the procedure, the patient had bright red blood per rectum followed by bloody diarrhea.
Her abdomen was soft and non-tender with minimal distention and positive bowel sounds. The
patient’s hemoglobin decreased to 7.5 g/dl from 9.0 g/dl, and she received a blood transfusion.
Upper endoscopy and enteroscopy demonstrated diffuse hemorrhagic gastritis and duodenitis.
The bleeding was controlled and the patient remained hemodynamically stable. Ultimately, the
patient did well and was discharged home.
Discussion: We report a case of a patient with known history of gastritis and duodenitis, who
developed severe upper GI bleeding immediately following the celiac plexus neurolysis. There
are no published reports documenting similar cases. It is difficult to offer a precise physiologic
explanation for this complication. However, we speculate that inhibition of sympathetic tone
from the celiac plexus neurolysis caused increased blood flow to the GI system, and this resulted
in active bleeding from previously indolent hemorrhagic gastritis and duodenitis.
Conclusion: It may be beneficial for patients with a history of gastritis, duodenitis or GI
bleeding to undergo a careful upper GI evaluation prior to celiac plexus neurolysis.
Key words: Case report, pancreatic cancer, celiac plexus neurolysis, anemia, hemorrhagic
gastritis and doudenitis, sympathetic block
Alternative Approach To Needle Placement In
Cervical Spinal Cord Stimulator Insertion
Authors: Zhu Jie
Published: March 2021

Background: Neuromodulation with spinal cord stimulation is a proven cost
effective treatment for the management of common conditions such as chronic
radicular leg pain from failed back surgery syndrome, complex regional pain
syndrome, and other painful neuropathic pain syndromes. The traditionally
instructed method for percutaneous spinal cord stimulator (SCS) lead placement
promotes the use of a “loss of resistance” (LOR) technique under anteroposterior
(AP) fluoroscopic guidance to assure midline lead placement and proper entry
into the epidural space.
Objective: To describe the relevant anatomy and method for a precise
needle placement approach for placement of percutaneous cervical spinal cord
stimulation (SCS) leads without loss of resistance (LOR) using a syringe. An
oblique fluoroscopic view is presented demonstrating successful placement of
cervical SCS leads.
Design: Technical report.
Setting: Pain management clinic.
Methods: Discussion with accompanying fluoroscopic images. This technical
report meets HIPAA compliance standards.
Results: Successful placement of percutaneous SCS leads without traditional
loss of resistance using an oblique fluoroscopic approach.
Limitations: Technical report only. The risks, potential complications, and
benefit from this approach are beyond the scope of the article.
Conclusions: This fluoroscopic technique provides an alternative means for
placing percutaneous cervical SCS leads without the use of the traditional loss of
resistance technique.
Key words: spinal cord stimulation, neuromodulation, cervical spine, fluoroscopy,
loss of resistance, epidural injection, neuropathic pain, failed neck surgery.
Comparative Evaluation of the Accuracy
of Benzodiazepine Testing in Chronic Pain
Patients Utilizing Immunoassay with Liquid
Chromatography Tandem Mass Spectrometry (LC/
MS/MS) of Urine Drug Testing
Authors: Manchikanti Laxmaiah
Published: March 2021

Background: Eradicating or appreciably limiting controlled prescription drug abuse, such as
opioids and benzodiazepines, continues to be a challenge for clinicians, while providing needed, proper
treatment. Detection of misuse and abuse is facilitated with urine drug testing (UDT). However, there
are those who dispute UDT’s diagnostic accuracy when done in the office (immunoassay) and claim
that laboratory confirmation using liquid chromatography tandem mass spectrometry (LC/MS/MS) is
required in each and every examination.
Study Design: A diagnostic accuracy study of UDT.
Study Setting: The study was conducted in a tertiary referral center and interventional pain
management practice in the United States.
Objective: Comparing UDT results of in-office immunoassay testing (the index test) with LC/MS/
MS (the reference test).
Methods: A total of 1,000 consecutive patients were recruited to be participants. Along with
demographic information, a urine sample was obtained from them. A nurse conducted the immunoassay
testing at the interventional pain management practice location; a laboratory conducted the LC/MS/
MS.
All index test results were compared with the reference test results. The index test’s efficiency (agreement)
was calculated as were calculations for sensitivity, specificity, false-positive, and false-negative rates.
Results: Approximately 36% of the specimens required confirmation. The index test’s efficiency
for prescribed benzodiazepines was 78.4%. Reference testing improved accuracy to 83.2%, a 19.6%
increase, and 8.9% of participants were found to be taking non-prescribed benzodiazepines. The index
test’s false-positive rate for benzodiazepines use was 10.5% in patients receiving benzodiazepines.
Limitations: This study was limited by its single-site location, its use of a single type of point of care
(POC) kit, and reference testing being conducted by a single laboratory, as well as technical sponsorship.
Conclusion: Clinicians should feel comfortable conducting in-office UDT immunoassay testing.
The present study shows that it is reliable, expedient, and fiscally sound for all involved. In-office
immunoassay testing compares favorably with laboratory testing for benzodiazepines, offering both
high specificity and agreement. However, clinicians should be vigilant and wary when interpreting
results, weighing all factors involved in their decision.
Key words: Controlled substances, benzodiazepines, opioids, illicit drugs, abuse, liquid
chromatography tandem mass spectrometry, immunoassay, urine drug testing
Patient Selection and Outcomes Using a LowDose Intrathecal Opioid Trialing Method for
Chronic Nonmalignant Pain
Authors: Grider Jay S.
Published: March 2021

Background: Various methods exist for trialing patients for intrathecal drug delivery. Currently
no standards exist regarding “best practices” for trialing techniques.
Objectives: The specific aim of the current study is to report results of patients trialed using a
low-dose intrathecal morphine technique in the treatment of chronic noncancer pain.
Setting: academic pain medicine practice
Study Design: Retrospective Review
Method: Visual analog pain scores (VAS) were obtained at the initial visit, after a 6 week
opioid-free interval prior to trial, at intrathecal doses of 25, 50, 100, 200 and 400 µg of
intrathecal morphine during the trial, at one month post-implant, and current VAS. Additionally,
intrathecal opioid doses at implant and current state are reported.
Results: VAS scores at the initial visit and after 6 weeks of opioid cessation were identical.
There was a significant improvement in VAS after the trial, which was sustained over the course
of therapy. Additionally, the use of the protocol described in this article suggests that the doseresponse relationship following opioid cessation is in the 50-400 µg/d range for intrathecal
morphine and that tolerance may be reversed during the 6 week opioid-free period.
Limitations: Small trialing study
Conclusions: Opioid taper and a 6 week opioid-free period may 1) improve long-term
analgesia versus a combination of oral/ intrathecal drug delivery system therapy 2) it may be
possible to maintain analgesia at microgram doses and 3) opioid tolerance may be reversible in
6 weeks. Further it appears that a dose response relationship for effective analgesia may be less
than 400 µg of intrathecal morphine.
Key Words: Intrathecal opioids, intrathecal drug delivery, oral opioid therapy, chronic
noncancer pain
The Dosages of Corticosteroid in
Transforaminal Epidural Steroid Injections for
Lumbar Radicular Pain Due to a Herniated Disc
Authors: Hwang Byeong Mun
Published: March 2021

Background: Intervertebral disc herniations are the most common cause of
lumbosacral radiculopathy, and transforaminal epidural steroid injection (TFESI)
is an important tool in treating lumbosacral radiculopathy. But the ideal dose
of corticosteroid in the epidural management of lumbosacral radiculopathy has
yet to be determined.
Objective: The aim of this study was to determine the effective dose of
steroids in TFESI for pain reduction in patients with lumbosacral radiculopathy.
Study Design: A randomized, double blind, controlled trial
Setting: An interventional pain management practice center.
Methods: A total of 160 participants received 2 epidural injections of either 5
mg, 10 mg, 20 mg, or 40 mg of triamcinolone in one week intervals via TFESI.
The degree of participant satisfaction and verbal numerical rating scale (VNRS)
were assessed at pretreatment, one week, and 2 weeks after the first TFESI.
Results: The number of participants experiencing pain relief was significantly
less than in other groups in the 5 mg triamcinolone group at one week after
the first TFESI. There were no significant differences among the groups at one
week after the second TFESI. VNRS decreased in the other groups except the
triamcinolone 5 mg group at one week after the first TFESI. VNRS decreased in
all groups at one week after the second TFESI.
Limitations: The limitations include lack of placebo control group and lack
of long-term follow-up.
Conclusions: We recommend a minimal effective dose of corticosteroid
(triamcinolone 10 mg) in TFESI for patients with lumbosacral radiculopathy.
Key words: herniated disc, steroid, transforaminal epidural steroid injection,
triamcinolone
Dural Sac Cross-Sectional Area Does Not
Correlate with Efficacy of Percutaneous
Adhesiolysis in Single Level Lumbar Spinal
Stenosis
Authors: Park Dr. Chan Hong
Published: March 2021

Background: Spinal stenosis is a narrowing of the spinal canal, which causes
mechanical compression of spinal nerve roots. The compression of these nerve roots
can cause low back pain and/or leg pain, as well as neurogenic claudication.
Lumbar epidural steroid injections have commonly been used in patients with
lumbar spinal stenosis (LSS). In cases that are refractory to epidural steroid injections,
percutaneous epidural adhesiolysis has been used.
Objective: The aim of our study is to determine the relationship between the severity
of spinal stenosis and the participants’ response to adhesiolysis, and to evaluate the
mid-term effectiveness of adhesiolysis.
Study Design: A prospective observational study.
Methods: Sixty-six patients with degenerative LSS were enrolled in this prospective
study. All participants underwent lumbar spine magnetic resonance imaging (MRI). The
cross-sectional area of the dural sac was measured on the transverse angled sections
through the central part of the disc on conventional MR images. All percutaneous
adhesiolyses were performed in the operating room. One hour following the procedure,
6 mL of 8% sodium chloride solution was infused during 30 minutes in the recovery
room while the patient underwent monitoring. Outcome measures were obtained
using the 5-point patient satisfaction scale at 2 weeks and 6 months post-treatment.
To evaluate outcome predictors, we divided the participants into 2 groups according to
their response to treatment.
Limitations: Secondary outcomes were not measured and the study did not include
a long-term follow-up period.
Results: Improvement (including reports of slightly improved, much improved, and no
pain) was observed in 49 participants (74.2%) at 2 weeks and 45 participants (66.7%)
at 6 months after the procedure. The dural sac cross-sectional area (DSCSA) did not
differ between participants who reported improvement and those who did not. There
was no statistically significant correlation between pain relief and DSCSA, age, or
participant sex.
Conclusion: Percutaneous adhesiolysis was shown to be effective for the treatment
of LSS, with mid-term result, without affecting DSCSA.
Key words: Low back pain, lumbar spinal stenosis, failed back surgery syndrome,
dural sac, interventional techniques, epidural injection, percutaneous adhesiolysis.
Alternative Approach To Needle Placement In
Spinal Cord Stimulator Trial/Implantation
Authors: Zhu Jie
Published: March 2021

Neuromodulation with spinal cord stimulation is a proven, cost effective treatment
for the management of chronic radicular low back pain from failed low back surgery
syndrome and other neuropathic pain conditions. The traditionally instructed method
for percutaneous spinal cord stimulator lead placement promotes the use of a “loss
of resistance” technique under anteroposterior fluoroscopic guidance to assure
midline lead placement and proper entry into the epidural space. Loss of resistance
is a reliable method to locate the epidural space in most clinical situations. However,
in certain circumstances such as a congenital underdeveloped ligamentum flavum
or defects of the ligamentum flavum, sometimes occurring after lumbar spine
surgery, it might become difficult to use a loss of resistance technique to locate the
epidural space. In this case, the level of resistance might not be clear. Further, a false
loss of resistance might occur between changes in fascial planes that might lead to
the uncertainty of needle depth. This paper introduces an alternative method for
needle placement for spinal cord stimulator (SCS) trials and implantation without
using the traditional loss of resistance technique. The technique allows for precise
visual monitoring of the Tuohy needle tip under fluoroscopy to gauge needle depth
as it enters into the tissue and the epidural space based on anatomic structural
landmarks. This method allows for multiple lead placement or single lead insertion
multiple times in the same interlaminar space. This is an alternative approach to
the loss of resistance technique based on the fluoroscopic landmarks. Theoretically,
this should be a safer approach for accessing the epidural space; however, further
studies are needed to evaluate its safety.
Key words: spinal cord stimulator, loss of resistance, epidural access, lumbar
radicular symptoms of lower limbs, neuromodulation, posterior column stimulator
Laser Doppler Imaging: Usefulness in Chronic
Pain Medicine
Authors: Grothusen John R.
Published: March 2021

Sympathetic nervous system dysfunction is thought to be a factor in neuropathic pain
conditions such as Complex Regional Pain Syndrome and in vascular conditions such as
Raynaud’s phenomenon. Laser Doppler fluxmetry has been used as a fast non-invasive
method to quantify changes in skin capillary blood flow which reflect activation of
sympathetically mediated vasoconstriction of the arterioles that supply the capillaries.
Studies of dynamic change of skin capillary blood flow with sympathetic activation such
as cold or inspiratory gasp have generally used single point laser Doppler systems where
the probe is in contact with the skin. The results are a single line tracing representing the
capillary flow at a single point on the skin a few millimeters in diameter.
Laser Doppler imaging (moorLDI laser Doppler imager, Moor Instruments Ltd.) allows for
non-contact recording of skin blood flow of an area as large as 50 centimeters square
with a resolution of 256 by 256 pixels and 4 milliseconds per pixel. Most work with laser
Doppler imaging has studied changes that occur between successive scans. We have
found it useful to look at changes that occur during a scan. In this way we obtain data
that is comparable to the time resolution of single point laser Doppler methods, but with
the larger spatial information that is available with laser Doppler imaging.
We present a small series of case reports in which inspiratory gasp during laser Doppler
imaging was able to provide quick, useful and unequivocal clinical information regarding
the status of regional bilateral skin capillary response to sympathetic activation. This may
be useful for distinguishing sympathetically mediated from sympathetically independent
pain. We believe the methods described may provide the basis for future quantitative
studies similar to those that use single point laser Doppler methods.
Key words: Laser doppler, laser Doppler imaging, sympathetically maintained pain,
Raynaud’s phenomen, complex regional pain syndrome
Use of Observational Mechanical Gateway
Connector in Spinal Cord Stimulation Trials
Authors: Kim Chong H.
Published: March 2021

Background: Spinal cord stimulation (SCS) is an established treatment option for chronic
pain. Prior to permanent implantation, temporary trials are performed to evaluate the SCS
treatment. Currently there are multiple manufacturers with varying fundamental differences
in delivery and resultant paresthesias. However, trials are typically limited to one manufacturer
for the patient to evaluate.
Objective: To evaluate the role of the Observational Mechanical Gateway (OMG) Connector
for patients undergoing SCS trials.
Study Design: Retrospective cohort design study. Patients undergoing SCS trials were
offered at the end of the 7 day trial to experience stimulation using the OMG Connector.
Setting: Academic university-based pain management center.
Method: Participants were trialed using the OMG Connector at the end of the 7 day spinal
cord stimulation trial. Data based on participants’ preference were collected.
Results: The average pain score at baseline was 7.3 on a 10-point scale overall, with
improvement during the SCS trial to 2.9 overall; 3.5 in Medtronic (MT); and 2.4 in St. Jude
(SJ) SCS trials (P = 0.04). The average pain score with OMG was 2.6 overall; 2.8 in MT; and
2.4 in SJ (P = 0.28). In terms of overall coverage of pain distribution, paresthesia and overall
satisfaction, the P values were 0.24, 0.21 and 0.33 respectively. Overall, 12 of 16 participants
underwent permanent implantation. One of the 4 failed trials was successfully retrialed with
the OMG Connector.
Limitations: Small sample of participants and the duration of the OMG Connector trial.
Conclusions: The OMG Connector offers patients another opportunity to better access the
available treatment options during the SCS trial period.
Key words: Spinal cord stimulation, OMG Connector, paresthesia, neurostimulation,
constant current, constant voltage, chronic pain, dorsal column
Kyphoplasty for the Treatment of Vertebral
Compression Fractures in a Cancer Patient with
Neurological Deficits and Anterior Vertebral
Wall Destruction
Authors: Choi Sang Sik
Published: March 2021

Background: Percutaneous balloon kyphoplasty is an effective, minimally invasive
procedure that is used to relieve pain and stabilize spine fractures caused by severe
osteoporosis or osteolysis due to tumor metastasis. However, there remains a risk of
bone cement leakage during and after kyphoplasty, especially in cases with severe
vertebral wall destruction or neurological deficits.
Objective: This article presents a case in which kyphoplasty was used to manage
these complications in a woman with vertebral compression fractures caused by tumor
metastasis.
Design: Case report.
Setting: Pain management clinic.
Methods: The patient was a 76-year-old woman who had severe low back pain,
lower extremity weakness, and cauda equina syndrome because of vertebral
compression fracture and spinal metastasis with epidural involvement. The patient
had a large bony defect in the vertebra that the bone filler device could pass freely
through the anterior body wall. Nevertheless, kyphoplasty was successfully performed
by using our new cement injection technique, which is a slow injection of the highly
viscous bone cement, followed by a second injection 10 minutes later to allow the
previously injected cement to harden.
Results: The procedure significantly alleviated all symptoms. The day after the
procedure, in the absence of additional pain medication, the pain had dropped
dramatically to a numerical rating scale 3-4, and there was an improvement in motor
function that allowed the patient to sit and go to the bathroom by herself. In addition,
the voiding sensation had returned, which allowed the patient to defecate and urinate
normally.
Limitations: This report describes a single case report.
Conclusion: Our new cement injection technique may allow balloon kyphoplasty
to be safely and effectively performed in cancer patients with pathological vertebral
compression fractures, even if there are large defects in the anterior vertebral wall and
neurological deficits.
Key words: Compression fractures, kyphoplasty, metastasis, neurological deficits,
osteolysis, polymethylmethacrylate.
Feasibility Study of Rapid Opioid Rotation and
Titration
Authors: Pappagallo Marco
Published: March 2021

Background: Opioid guidelines recommend opioid rotation and switching for patients who
do not achieve adequate pain relief or who experience intolerable adverse events (AEs) with
their current opioid. However, specific recommendations and protocols for opioid rotation
are lacking, making the practice time consuming and difficult for primary care physicians to
accomplish independently or coordinate with a pain specialist.
Objectives: To assess the safety and feasibility of using 24-hour intravenous patientcontrolled analgesia (IV-PCA) to achieve rapid opioid rotation and titration (RORT).
Study design: Open-label pilot study.
Setting: Hospital research center.
Methods: At admission, patients (aged ≥ 18 years) with treatment-refractory chronic pain
who were taking morphine or oxycodone for ≥ 3 months and had pain scores ≥ 4 on a 10-
point scale, underwent opioid rotation to oral oxymorphone extended release (ER). They also
received IV-PCA oxymorphone for 24 hours as needed. At discharge, the participants were
taking oral oxymorphone ER with oxymorphone immediate release (IR) as needed based on
their total 24-hour oral plus IV-PCA oxymorphone use. During a 2-week follow-up, their
oxymorphone usage was titrated as needed. Main outcome measures were AEs, Patient Global
Impression of Change (PGIC), Brief Pain Inventory (0 = no pain/interference, 10 = worst pain/
complete interference), treatment satisfaction, and change in oxymorphone dose.
Results: Twelve patients enrolled and completed the 24-hour IV-PCA; 10 completed the 2-
week follow-up post–24-hour IV-PCA. PGIC status improved by 12 hours (odds ratio [OR],
0.19, 95% CI, 0.08−0.44; P < 0.001), and both PGIC status and activity scores improved
by 24 hours (OR, 0.23, 95% CI, 0.09−0.55; P = 0.001; OR, 0.49, 95% CI, 0.25−0.96; P =
0.04, respectively) and 2 weeks (OR, 0.14, 95% CI, 0.04−0.46; P = 0.001; OR, 0.21, 95%
CI, 0.06−0.72; P = 0.01) versus 6 hours. During the 24-hour IV-PCA time period, 6 of 10
patients accomplished ≥ 50% of their overall dose titration. At 2 weeks, 8 of 10 participants
were Greatly Satisfied or Somewhat Satisfied with the overall RORT procedure. RORT was
well tolerated, with no serious AEs.
Limitations: This was a pilot open-label study in a small number of participants. A larger
randomized study with long-term follow-up and comparison to traditional protocols is
necessary.
Conclusions: Preliminary data suggest that RORT can be performed safely and effectively by
incorporating IV-PCA during the first 24 hours. Further investigations are needed to determine
whether RORT can become an ambulatory treatment intervention in pain practice.
Clinicaltrials.gov registration: NCT00580294
Key words: chronic pain, opioid rotation, opioid switching, opioid substitution, opioid
conversion, oxymorphone, oxycodone, morphine
Placebo and Nocebo in Interventional Pain
Management: A Friend or a Foe – Or Simply
Foes?
Authors: Manchikanti Laxmaiah
Published: March 2021

The present evidence illustrates that the placebo effect depends on a variety
of neurochemical and neurophysiological mechanisms, which are measurable
and modifiable. However, the placebo response is inexorably tied to the
treatment context. All medical treatments take place in a particular context;
this context includes the therapist’s attitudes, psychosocial factors affecting
the therapeutic relationship, and the patient’s mindset. Therapeutic efficacy
at least in part is attributable to the concordance between the proposed
treatment and the patient’s belief system. It is this fraction of the therapeutic
response that is commonly called the placebo effect. More formally, the
placebo effect is defined as that part of the therapeutic response that is not
attributable to the properties of active ingredients.
A proposed model of the placebo effect includes a complex reaction with
induction, psychophysiological mediators, neurobiological mediators, and
actualization of effects. Similarly, nocebo hyperalgesia is also explained by
neurobiological mechanisms resulting in anxiety and nocebo hyperalgesia.
Functional neuroanatomy of placebo indicates an anticipation phase and
modulation phase or placebo response.
In modern medicine it is well recognized that the treatment effect of many
active interventions is related to both an active treatment component and
the placebo component. Thus, clinical implications are enormous as such
placebo analgesia and nocebo hyperalgesia are not simply response biases.
Instead, they are the product of neurophysiological processes that modulate
the integration of the nociceptive signals throughout the central nervous
system. Thus, it has been suggested that clinicians should not try to avoid the
placebo effect. On the contrary, they should try to potentiate it, since this is
a very important clinical implication.
From the research perspective, the emerging knowledge of placebo continues
to cast doubts on the appropriateness of the double-blind placebo-control
design in assessing efficacy of treatment - specifically involving interventional
techniques or surgery. The research setting itself may introduce nocebo
hyperalgesia.
Key words: Placebo, placebo analgesia, placebo treatment, placebo effect,
nocebo, nocebo hyperalgesia, psychophysiological mediators, neurobiological
mediators, inert agent