bluuebunny/crossref_metadata_2025 huggingface dataset:
The Best-Laid Plans of “Back Mice” and Men:
A Case Report and Literature Review of
Episacroiliac Lipoma
Authors: Bicket Mark C.
Published: February 2021

Background: Back mice, or episacroiliac lipoma, represent a potentially treatable cause of low
back pain that may be under-recognized in clinical practice. Despite being well characterized
based on clinical history and physical examination findings, implementation of appropriate
treatment may be delayed or missed based on a lack of familiarity with the diagnosis.
Objectives: In this case report and literature review, we describe a 47-year-old woman with
history of persistent low back pain who presented with a pain exacerbation consistent with a
back mouse. The history, epidemiology, clinical characteristics, differential diagnosis, potential
mechanisms for pain, and treatment options for back mice were then reviewed.
Study Design: Case report and literature review.
Setting: Academic university-based pain management center.
Results: Studies included one randomized clinical trial, 4 cross-sectional studies, 8 case reports
or series, and 16 other publications prior to 1967.
Limitations: A single case report.
Conclusions: Firm, rubbery, mobile nodules that are located in characteristic regions of the
sacroiliac, posterior superior iliac, and the lumbar paraspinal regions may represent fatty tissue
that has herniated through fascial layers. When painful, these back mice may be confused
with other causes of low back pain. In particular, the presence of point tenderness may mimic
myofascial pain, and reports of radicular pain may imitate herniated nucleus pulposus. However,
back mice may be distinguished from other entities based on findings from the history and
physical examination such as absence of neurological deficit. Treatment consisting of injection
of local anesthetic into the nodule with or without corticosteroid followed by repeated, direct
needling has been reported to relieve pain in many case reports. The one clinical trial comparing
injection of local anesthetic to normal saline, which did not include repeated needling, found
only mild and transient benefit in the treatment group.
Key words: Low back pain, back mice, back mouse, episacroiliac lipoma, lumbar subcutaneous
nodules, multifidus triangle syndrome, subcutaneous fatty nodes, case report, review
Treatment Outcomes after Combination
Interventional and Cognitive Motivational
Counseling on Analgesic Medication Use in
Patients with Chronic Spine Pain
Authors: Jerome John
Published: February 2021

Background: Pain interventionists can interrupt pain through anesthetic blockade of neural
transmission to virtually any part of the body. Temporary pain relief can be achieved by the
direct application of targeted anesthetic. Diagnostically, nerve blocks help identify specific pain
generators, refine differential diagnosis, and disrupt the neural transmission mechanisms to stop
pain generation peripherally.
Objective: This study of patients with chronic spine pain was conducted to test the hypothesis that
decreasing pain through interventional techniques coupled with cognitive motivational counseling
can be highly effective in reducing chronic pain interference, reliance on prescription opioids, and
enhancing overall function and quality of life.
Study Design: Retrospective case series.
Setting: Rehabilitation center.
Methods: Patients: This study involved a retrospective cohort of 78 consecutive patients with
spine pain that underwent interventional procedures and cognitive motivational counseling, as
well as a comparison group of 77 consecutive patients that underwent interventional procedures
only. Outcome Measures: Pain intensity (DoD VAS), Functional capacity (DoD SS), Global Appraisal
(PGIC), Pain site measurement (Drawing), and prescription medication use questionnaires were
administered at initial evaluation and after treatment. Pre- and post-treatment changes were
compared using paired t-tests. Chi-squared analysis was performed pre- and post-treatment for
medication use.
Results: The pre- and post-treatment scores for pain intensity, function, and global appraisal
demonstrated significant response to treatment (P < 0.001) for the combined interventional and
cognitive motivational group (P < 0.001) and the interventional only group (P < 0.05). Compared
to initial intake, opioid (P < 0.01), benzodiazepine (P < 0.01), muscle relaxant (P < 0.05), and
antidepressant/antianxiolytic (P < 0.05) use only decreased for the combined interventional and
cognitive motivational group.
Limitations: This is a retrospective study using medical records and patient self-reported
symptoms with possible missed coding and no true random selection, assignment, or
genuine control group comparison.
Conclusion: This study’s results support the hypothesis that a combined interventional and
cognitive motivational counseling treatment program can be effective in decreasing spine pain,
reducing prescription pain medication use, and improving overall quality of life in chronic spine
pain patients.
Key words: Spine pain, interventional pain procedures, cognitive motivational counseling,
analgesic medication
Anatomical Flow Pattern of Contrast in Lumbar
Epidural Space: A Human Study with a Midline
vs. Parasagittal Interlaminar Approach under
Fluoroscopy
Authors: Kazempour Morteza Kazempour
Published: February 2021

Background: Epidural injections for managing chronic back pain are one of the most
commonly performed interventions; however, controversy continues regarding the most
effective method of epidural injections. A ventral distribution of epidural injected drug plays
a significant role in its effectiveness.
Objective: To determine the distribution of a drug in the epidural space after parasagital
and midline epidural injection.
Setting: Academic hospital.
Study Design: In randomized double-blind clinical trial, patients with a diagnosis of low
back pain (LBP) and unilateral lumbosacral radicular pains were randomized to receive drug
through either parasagital or midline approach.
Methods: Patients were assessed for anterior epidural spread of contrast under fluoroscopy
in anteroposterior and lateral views. After epidural space confirmation, triamcinolone (80 mg)
plus bupivacain was injected and patients were followed up for 2 weeks.
Results: Fifty-six patients enrolled in the study. Successful infiltration of the drug into the
ventral epidural space was successfully achieved in 75% of cases in the parasagital group but
in only 25% of the cases in using a midline approach. Effective pain relief (numeric rating
scale [NRS] < 3) was observed in 76.5% of patients in the parasagital group and 24.5% of
patients in the midline group (P = 0.001) at 2 weeks. Number of patients with improved
disability (measured by Oswestry Disability Index [ODI] < 20%) was significantly higher in the
parasagital group (78%) compared to the midline group (26%) at 2 weeks (P = 0.002).
Limitations: The results of the current study should be interpreted in relation to the study
design and future studies should include larger patient numbers and longer follow-up time.
However, the results are consistent with previous studies.
Conclusion: Parasagital epidural injection showed higher infiltration of the drug to the
ventral epidural space compared to the midline approach. The higher infiltration of the ventral
epidural space provides better improvement of clinical disability and pain in the parasagital
group.
Key words: Epidural, midline, parasagital, ventral distribution, disc herniation
Analysis of Psychological Characteristics
Impacting Spinal Cord Stimulation Treatment
Outcomes: A Prospective Assessment
Authors: Duarte Rui V.
Published: February 2021

Background: Psychological factors are recognised as influencing the outcome of spinal cord
stimulation (SCS) although there is currently no consensus as to which factors impact upon SCS
efficacy.
Objective: To identify psychological characteristics that may impact the efficacy of SCS.
Study Design: Prospective evaluation.
Setting: Single secondary care center in Dudley, United Kingdom.
Methods: Patients: Seventy-five patients were initially recruited and 56 patients (31 women
and 25 men) were followed-up for 12-months. Intervention: SCS for the management of chronic
non-cancer pain. Main Outcome Measures: Outcome measures assessed at baseline, 6 months,
and 12 months following SCS implantation included the visual analogue scale (VAS), Oswestry
disability index (ODI), hospital anxiety and depression (HAD) scale, and the pain coping strategies
questionnaire (PCSQ).
Results: Statistically significant improvements were observed for the VAS (P < 0.001), ODI (P =
0.011), anxiety (P = 0.042), and depression (P = 0.010) in the HAD scale and for the subscales
reinterpreting pain sensation (P = 0.018), control over pain (P = 0.001), and ability to decrease pain
(P < 0.001) of the PCSQ. We observed that depression and autonomous coping (control over pain,
ability to reduce pain, and catastrophizing) may impact sensory aspects such as pain intensity and
disability scores affecting the outcome of SCS treatment. Age at time of implant and duration of
pain prior to implant were also found to impact SCS efficacy.
Limitations: It has been reported that loss of analgesia may be experienced within 12 to 24
months following SCS implantation and therefore, it would be of interest to follow patients over
a longer period.
Conclusions: This study demonstrates that psychological aspects such as depression and
autonomous coping may impact SCS treatment. Addressing these issues prior to SCS implantation
may improve SCS long-term outcome.
Key words: Spinal cord stimulation, chronic pain, psychological characteristics, depression,
autonomous coping
Effects of Ultrasound-Guided Stellate Ganglion
Block on Acute Pain after Arthroscopic
Shoulder Surgery
Authors: Lee Mihyeon
Published: February 2021

Background and Objectives: Apart from a few case reports, the effectiveness
of stellate ganglion block (SGB) as a monotherapy in acute nociceptive pain has not
been determined. We aimed to assess the effects of SGB on postoperative pain after
arthroscopic shoulder surgery.
Study Design: Randomized, blind, controlled, clinical trial.
Setting: University Hospital outpatient.
Methods: Forty-six patients undergoing arthroscopic shoulder surgery were assigned
randomly to 2 groups: group S included patients who underwent SGB prior to surgery
and group C did not. In group S, subfascial ultrasound-guided SGB was conducted with
4 mL of 0.375% levobupivacaine. For the first postoperative 48 hours, postoperative
visual analog scale (VAS) and analgesic requirements were compared.
Results: The results of 40 patients were included in the study. There was no difference
between groups with regards to analgesics requirement for the first postoperative 48
hours and no difference in VAS score (P > 0.05).
Limitations: Small number of patients in study.
Conclusion: Preoperative ultrasound-guided SGB did not reduce postoperative acute
pain in arthroscopic shoulder surgery.
Key words: Acute pain, sympathetic nerve block, stellate ganglia
The Impact of Genetic Variation on Sensitivity
to Opioid Analgesics in Patients with
Postoperative Pain: A Systematic Review and
Meta-Analysis
Authors: Lu Prof. Lin
Published: February 2021

Background: Individual response to opioid analgesics varies among patients.
Objective: This study sought to clarify the impact of distinct genetic variations on pain, opioid
consumption, and opioid side effects in patients with postoperative pain.
Study Design: A systematic review and meta-analysis of associations between genetic singlenucleotide polymorphisms (SNPs) and opioids used for acute postoperative pain.
Setting: This meta-analysis examined all studies involving an association between genetic
polymorphisms and the analgesic efficacy or clinical outcome of opioid analgesics for postoperative
pain.
Methods: A literature search was performed up to January 31, 2014, using the PubMed, EMBase,
ISI Web of Science, and Cochrane Library databases.
Results: Fifty-nine studies were included in this systematic review, and 23 studies (a total of
5,902 patients) were included in the final meta-analysis. The results showed that human μ-opioid
receptor gene (OPRM1) 118G allele variant carriers consumed more opioids for analgesia (SMD
= -0.17, 95% CI = [-0.25, -0.10], P < 0.00001), but reported higher pain scores (MD = -0.11,
95% CI = [-0.17, -0.04], P = 0.002) and less nausea and vomiting (odds ratio = 1.30, 95% CI =
[1.08, 1.55], P = 0.005) than the homozygous 118AA patients during the first 24 hour but not
the 48 hour postoperative period. Moreover, CYP3A4*1G carriers consumed less opioids than
homozygous CYP3A4*1/*1 patients during the first 24 hours postoperative period (MD = 45.12,
95% CI = [36.17, 54.06], P < 0.00001). No significant differences were found in CYP3A5*3,
ABCB1 C3435T, and G2477T/A genetic polymorphisms.
Limitations: Some potential non-genetic factors can modify the effects of gene SNP on pain
and opioid consumption during the postoperative period, such as age, gender, mood, anxiety, and
drug-drug interactions. But further analyses could not be performed in the present meta-analysis
due to limited information.
Conclusion: The results indicate that among the genetic SNPs we studied which include those
affecting analgesic drug metabolism, transport of analgesic agents across the blood-brain barrier,
and their activity at target receptors and ion channels and in the modulation of neurotransmitter
pathways, the A118G allele variant of OPRM1 has the most potent influence on pain management
of postoperative patients. Opioid receptor gene information may provide valuable information for
clinicians to properly manage the analgesic use of opioids individually for better pain management.
Key words: Postoperative pain, meta-analysis, single-nucleotide polymorphism, opioid
Systematic Review of Radiofrequency
Ablation and Pulsed Radiofrequency for
Management of Cervicogenic Headache
Authors: Asopa Amit
Published: February 2021

Background: Cervicogenic headache is a secondary headache that has a source in the
upper cervical spine. There is a small but growing body of evidence to establish effectiveness
of radiofrequency (RF) neurotomy, and the pulsed RF (PRF) procedure for management of
cervicogenic headache.
Objective: To investigate the clinical utility of RF neurotomy, and PRF ablation for the
management of cervicogenic headache.
Study Design: Systematic review.
Methods: The review included relevant literature identified through searches of PubMed,
Cochrane, Clinical trials, U.S. National Guideline Clearinghouse and EMBASE from 1960
to January 2014.The quality assessment and clinical relevance criteria utilized were the
Cochrane Musculoskeletal Review Group criteria for randomized control trials and the
Newcastle-Ottawa Scale criteria for observational studies. The level of evidence was
classified as good, fair, and poor based on the quality of evidence.
Outcomes Measured: The primary outcome measures were reduction in pain scores
and improvement in quality of life.
Results: The primary outcome measures were headache relief and improved quality of
life. Twenty five studies were identified for full text review of these, 9 studies met inclusion
criteria. There were 5 non-randomized, among them 4/5 were of moderate quality, 3/5
showed RF ablation and 1/5 showed PRF as an effective intervention for cervicogenic
headache. There were 4 randomized trials among them 2/4 were of high quality, 3/4
investigated RF ablation as an intervention for CHA, 1/4 investigated PRF ablation as an
intervention for CHA and none of the randomized studies showed strong evidence for RF
and PRF ablation as an effective intervention for CHA.
Limitations: In the selected studies there were inconsistencies between randomized
trials, flaws in trial design, and gaps in the chain of evidence.
Conclusion: There is limited evidence to support RF ablation for management of CHA as
there are no high quality RCTs and/ or multiple consistent non-RCTs without methodological
flaws. There is poor evidence to support PRF for CHA as there are no high quality RCTs or
Non-RCTs.
Key Words: Chronic pain, cervicogenic headache, radiofrequency (rf) neurotomy, pulsed
radiofrequency (PRF) ablation, reduction in pain, improvement in quality of life, level of
evidence
Comparison of High-Viscosity Cement
Vertebroplasty and Balloon Kyphoplasty
for the Treatment of Osteoporotic Vertebral
Compression Fractures
Authors: Nie Lin
Published: February 2021

Background: Percutaneous vertebroplasty is a widely used vertebral augmentation procedure
for treating osteoporotic vertebral compression fractures (OVCFs). But high cement leakage
rate caused by a low-viscosity cement and high injection pressure has limited its general use.
Balloon kyphoplasty (BKP) and high-viscosity cement vertebroplasty (HVCV) are 2 modifications
of vertebroplasty designed to decrease cement leakage.
Objective: To assess the safety and efficacy of HVCV compared with BKP.
Study Design: A prospective cohort study.
Setting: Department of Spine Surgery, an affiliated hospital of a medical university.
Method: One hundred seven patients suffering from painful OVCFs were randomly assigned
into HVCV or BKP groups. Visual Analog Scale (VAS), Oswestry Disability Index (ODI), cement
leakage, and vertebral height restoration were evaluated. All occurring complications and
injected cement volumes were recorded. The follow-up time was one year.
Results: VAS and ODI scores improved in both groups, and did not differ significantly between
the 2 groups. More cement was used in the BKP group than in HVCV group (4.22 vs. 3.31
mL, P < 0.0001). The incidence of cement leakage in the HVCV group was lower than that of
the BKP group (13.24% vs 30.56%, P < 0.05). No symptomatic cement leakages occurred in
the HVCV group. In the BKP group, one patient experienced discogenic back pain related to a
disc leak, and another patient had asymptomatic cement emboli in the lung related to venous
leakage. The mean compression rate before the procedure was 29.98% in the HVCV group
and 28.67% in the BKP group (P = 0.94). The vertebral height was improved significantly
and maintained at one-year follow-up in both groups. BKP was more effective in vertebral
height restoration than HVCV (44.87% vs. 23.93%, P < 0.0001). There was one case of a new
adjacent vertebral fracture in the HVCV group (2%), and 4 cases of new nonadjacent vertebral
fractures in the BKP group (7.84%) (P = 0.18).
Limitations: A single-center and relatively small-sample size study.
Conclusion: HVCV and BKP are safe and effective in improving quality of life and relieving
pain. HVCV has a lower cement leakage rate, whereas BKP is more effective in vertebral height
restoration. Subsequent fractures are not different between the 2 groups.
Key words: Vertebral compression fracture, spine, osteoporosis, cement augmentation,
balloon kyphoplasty, vertebroplasty, cement leakage
Concordant Pain Provocation During
Transforaminal Epidural Steroid Injection for
Lumbosacral Radiculopathy: Effect on Pain
Outcome and Predictive Factors
Authors: McCormick Zack
Published: February 2021

Background: Anecdotal report suggests that provocation of pain during epidural steroid injection
(ESI) that is concordant with typical radicular symptoms predicts pain outcome following injection.
However, limited evidence exists that substantiates this theory. Additionally, there is a paucity of
literature investigating factors associated with the provocation of pain during ESI.
Objectives: The goal of this study was to determine whether provocation of concordant radicular
pain during transforaminal ESI predicts pain relief immediately after injection and at short-term
follow-up. Demographic, radiologic, and procedural factors associated with the pain provocation
and pain outcomes at immediate and short-term follow-up were also investigated.
Study Design: Longitudinal cohort study.
Setting: Urban academic outpatient interventional spine clinics.
Methods: Adults who underwent a fluoroscopically guided transforaminal ESI without sedation
between January 1, 2006, and October 29, 2007, for the treatment of lumbosacral radicular pain
were included in this study. The relationships between provocation of concordant pain, immediate
post-injection, and follow-up visual analogue scale (VAS) pain scores, as well as with demographic,
radiologic, and procedural factors were determined using chi-square/Fisher’s exact tests for
categorical variables and t-tests or ANOVA for numerical variables.
Results: One thousand twenty one patients, 42.4% (433) male/57.6% (588) female, with a
mean (SD) age of 54.1 (16.7) years were included in the study. Concordant pain provocation
did not predict the magnitude of pain reduction (P = 0.9255) or the frequency of achieving >
50% pain relief (P = 0.7449) at short-term follow-up. Radiologic evidence of foraminal stenosis or
nerve root impingement (P < 0.0001) and the lack of a medial-superior contrast flow pattern (P =
0.0199) were associated with a greater frequency of pain provocation during transforaminal ESI.
Limitations: This study is primarily limited by possible selection bias given that patients who
did not follow-up in the clinic could not be studied, and an incomplete follow-up rate (66%).
Conclusions regarding subacute and long-term pain outcomes cannot be determined from this
study as only short-term data were available.
Conclusions: Provocation of concordant radicular pain does not predict pain relief at short-term
follow-up after a transforaminal ESI. Foraminal stenosis, nerve root impingement, and lack of a
medial-superior contrast flow pattern are associated with pain during the transforaminal ESI. Thus,
clinicians should be aware of these radiologic and procedural risk factors for inciting pain during
transforaminal ESI.
Key words: Epidural steroid injection, lumbar, radicular pain, outcomes, prognostic
Pressure Pain and Isometric Strength of Neck
Flexors Are Related in Chronic Tension-Type
Headache
Authors: Castien Rene
Published: February 2021

Background: In patients with chronic tension-type headache (CTTH) changes in pressure pain in
the cervical region are associated with peripheral or central sensitization. It is hypothesized that an
increase of isometric strength of neck flexors would lead to a decrease of pressure pain in CTTH,
as an expression of reduced peripheral or central sensitization
Objective: In this study we aimed to analyze the correlation between change in isometric strength
of the neck flexors and change in pressure pain scores (PPS) in patients with CTTH.
Study Design: Comparative analysis of data from previous study.
Setting: Primary healthcare center.
Methods: Data from 145 patients with CTTH who underwent a manual therapy program
including isometric strength training of the neck flexors were analyzed at 8 and 26 weeks posttreatment. PPS were measured as a total of pain scores on a numeric rating scale (score 0 to 10)
on application of a pressure stimulus of 3kg/cm at 8 cervical- and suboccipital muscles. Isometric
strength of the neck flexors was measured in seconds. Correlations were computed between
changes in PPS and isometric neck flexor strength.
Results: Isometric strength of neck flexors scored significantly different compared to baseline
measurement (mean 30.0 seconds, sd:25.2), and increased with a mean difference of 17.33
seconds (95%CI: 20.61 to 14.05) at 8 weeks and 19.18 seconds (95%CI: 23.48 to 14.87) at 26
weeks. Similarly, compared to PPS baseline measurement (31.6 points, sd:18.6), mean difference
in PPS was significantly decreased at 8 and 26 weeks: -11.3 points (95%CI: -8.77 to -13.83) and
-11.15 points (95%CI: -8.31 to -13.99). There is a negative correlation between changes in PPS
and changes in isometric strength of neck flexors which is weak at 8 weeks (r = -0.243, P = 0.004)
and moderate at 26 weeks (r = -0.318, P < 0.000).
Limitations: Correlational analysis.
Conclusion: Decrease in PPS correlates with increases in isometric strength of neck flexors in
patients with CTTH in short- and long-term
Key words: Chronic tension-type headache, pressure pain, neck flexors, manual therapy,
sensitization, isometric strength, cervical spine
Occult Spinal Dysraphism: A Challenge in Pain
Management
Authors: Gerges Frederic J
Published: February 2021

Spina bifida is a common birth defect affecting the central nervous system and represents
a group of neural tube defects caused by congenital dysraphic malformations of the
vertebral column and/or spinal cord. The anatomy in these patients is challenging and
includes structural and vascular abnormalities including arteriovenous malformation or
fistulae, and fatty substitution of paravertebral tissues. A magnetic resonance image
(MRI) is needed for management of patients with lumbar radiculopathy and clinical
features suspicious of occult spinal dysraphism. Risks and benefits of lumbar epidural
steroids should be discussed comprehensively with those patients and in the best case
scenario be avoided. Occult spinal dysraphism poses a clinical dilemma for interventional
pain specialists managing those patients with lumbar radiculopathy. We report a case
of occult spinal dysraphism discovered following the development of post-traumatic
radicular symptoms.
Key words: Occult spinal dysraphism, spina bifida, lumbar radiculopathy, pain, pain
management, physical findings
Economic Analysis of Kiva VCF Treatment
System Compared to Balloon Kyphoplasty Using
Randomized Kiva Safety and Effectiveness Trial
(KAST) Data
Authors: Hornberger John
Published: February 2021

Background: Vertebral compression fractures (VCFs) are the most common osteoporotic fractures
and cause persistent pain, kyphotic deformity, weight loss, depression, reduced quality of life, and
even death. Current surgical approaches for the treatment of VCF include vertebroplasty (VP) and
balloon kyphoplasty (BK). The Kiva® VCF Treatment System (Kiva System) is a next-generation
alternative surgical intervention in which a percutaneously introduced nitinol Osteo Coil guidewire
is advanced through a deployment cannula and subsequently a PEEK Implant is implanted
incrementally and fully coiled in the vertebral body. The Kiva System’s effectiveness for the treatment
of VCF has been evaluated in a large randomized controlled trial, the Kiva Safety and Effectiveness
Trial (KAST). The Kiva System was non-inferior to BK with respect to pain reduction (70.8% vs.
71.8% in Visual Analogue Scale) and physical function restoration (38.1 % vs. 42.2% reduction in
Oswestry Disability Index) while using less bone cement. The economic impact of the Kiva system
has yet to be analyzed.
Objective: To analyze hospital resource use and costs of the Kiva System over 2 years for the
treatment of VCF compared to BK.
Setting: A representative US hospital.
Study Design: Economic analysis of the KAST randomized trial, focusing on hospital resource use
and costs.
Methods: The analysis was conducted from a hospital perspective and utilized clinical data
from KAST as well as unit-cost data from the published literature. The cost of initial VCF surgery,
reoperation cost, device market cost, and other medical costs were compared between the Kiva
System and BK. The relative risk reduction rate in adjacent-level fracture with Kiva [31.6% (95% CI:
-22.5%, 61.9%)] demonstrated in KAST was used in this analysis.
Results: With 304 vertebral augmentation procedures performed in a representative U.S. hospital
over 2 years, the Kiva System will produce a direct medical cost savings of $1,118 per patient
and $280,876 per hospital. This cost saving with the Kiva System was attributable to 19 reduced
adjacent-level fractures with the Kiva System.
Limitations: This study does not compare the Kiva System with VP or any other non-surgical
procedures for the treatment of VCF.
Conclusion: This first-ever economic analysis of the KAST data showed that the Kiva System for
vertebral augmentation is hospital resource and cost saving over BK in a hospital setting over 2
years. These savings are attributable to reduced risk of developing adjacent-level fractures with the
Kiva System compared to BK.
Key words: Vertebral compression fracture, vertebral augmentation, osteoporosis, adjacent-level
fractures, kyphoplasty, balloon kyphoplasty, Kiva System
Reducing Opioid Analgesic Deaths in America:
What Health Providers Can Do
Authors: Agarin Taghogho
Published: February 2021

Background: Available data have shown steady increases of drug overdose deaths between
1992 and 2011. We review evidenced-based recommendations provided by a few prominent
North American pain societies and suggest ways on how health providers might help reduce
opioid analgesic deaths by implementing these practices.
Objective: To identify health care providers’ roles in reducing opioid analgesic deaths.
Study Design: A comprehensive review of current literature.
Methods: The review included relevant literature identified through searches of MEDLINE,
Cochran reviews, and Google Scholar, PubMed and EMBASE from January 1998 to January
2014. The level of evidence was classified as I (good), II (fair), and III (limited) based on the
quality of evidence developed by the U.S. Preventive Services Task Force (USPSTF).
Results: Several practices such as too high doses overall, giving too high doses to opioid
naive patients, too fast opioid titration, insufficient use and knowledge of urine drug testing,
not updating knowledge of drug metabolism/interactions, and inadequate patient monitoring
are associated with higher risks of opioid analgesic deaths. Suboptimal risk stratification of
patients, rotation practices, and use of opioids analgesics in chronic noncancer pain are also
associated factors.
Limitations: There were a paucity of good evidence studies which show recommendations
reduce death.
Conclusion: Providers should be aware of all associated factors with opiate analgesic deaths
and apply the available evidence in reducing opioid analgesic deaths.
Key words: Opioid analgesic deaths, methadone deaths, opioid mortality, opioid guidelines,
genetic testing for opioids, urine drug testing
Superior Hypogastric Plexus Combined with
Ganglion Impar Neurolytic Blocks for Pelvic
and/or Perineal Cancer Pain Relief
Authors: Ahmed Doaa Gomaa
Published: February 2021

Background: The superior hypogastric plexus (SHGP) carries afferents from the viscera
of the lower abdomen and pelvis. Neurolytic block of this plexus is used for reducing
pain resulting from malignancy in these organs. The ganglion impar (GI) innervats the
perineum, distal rectum, anus, distal urethra, vulva, and distal third of the vagina. Different
approaches to the ganglion impar neurolysis have been described in the literature.
Objectives: To assess the feasibility, safety, and efficacy of combining the block of the
SHGP through the postero-median transdiscal approach with the GI block by the transsacro-coccygeal approach for relief of pelvic and/or perineal pain caused by pelvic and/or
perineal malignancies or any cancer related causes.
Methods: Fifteen patients who had cancer-related pelvic pain, perineal pain, or both
received a combined SHGP neurolytic block through the postero-median transdiscal
approach using a 20-gauge Chiba needle and injection of 10 mL of 10% phenol in saline
plus a GI neurolytic block by the trans-sacro-coccygeal approach using a 22-gauge 5 cm
needle and injection of 4 – 6 mL of 8% phenol in saline. Pain intensity (measured using
a visual analogue scale) and oral morphine consumption pre- and post-procedure were
measured.
Results: All patients presented with cancer-related pelvic, perineal, or pelviperineal
pain. Pain scores were reduced from a mean (± SD) of 7.87 ± 1.19 pre-procedurally to
2.40 ± 2.10 one week post-procedurally (P < 0.05). In addition, the mean consumption
of morphine (delivered via 30 mg sustained-release morphine tablets) was reduced from
98.00 ± 34.89 mg to 32.00 ± 28.48 mg after one week (P < 0.05). No complications or
serious side effects were encountered during or after the block.
Limitations: This study is limited by its small sample size and non-randomized study.
Conclusion: A combined neurolytic SHGP block with GI block is an effective and safe
technique for reducing pain in cancer patients presented with pelvic and/or perineal pain.
Also, a combined SHGP block through a posteromedian transdiscal approach with a GI
block through a trans-sacrococcygeal approach may be considered more effective and
easier to perform than the recently invented bilateral inferior hypogastric plexus neurolysis
through a transsacral approach.
Key words: Superior hypogastric plexus block, ganglion impar block, cancer pain, pelvic
pain, perineal pain
Resorption of Massive Lumbar Disc Herniation
on MRI Treated with Epidural Steroid Injection:
A Retrospective Study of 28 Cases
Authors: Kang Sang Soo
Published: February 2021

Background: Although herniated disc fragments may resolve spontaneously, the optimal
treatment option for massive lumbar disc herniation (LDH) has not been determined.
Objective: To evaluate the extent of reduction in the size of massive LDH on magnetic
resonance imaging (MRI) and the pain relief effect of transforaminal epidural steroid injection
(TFESI) during the study period.
Study Design: Retrospective evaluation.
Setting: Hospital and ambulatory pain clinic, Korea.
Methods: After Institutional Review Board approval, we conducted a retrospective review of
28 patients who underwent at least 2 MRIs during the period from January 2012 to December
2014. The size of the herniated mass was determined from the ratio of the anterior-posterior
diameter of the spinal canal (C-value) to the maximum anterior-posterior diameter of the
herniated disc (H-value) on axial MRI (C-H ratio). We also analyzed visual analogue scale (VAS)
scores at baseline (T0), 2 weeks after the first and second TFESI (T1, T2), and at the second
follow-up MRI (T3).
Results: The mean C-value was 18.3 ± 2.9 mm. The mean H-value changed from 10.4 ± 1.9
mm to 4.5 ± 2.7 mm, and the mean C-H ratio changed from 58 ± 1.0% to 24 ± 1.4% (P <
0.001). Twenty-four of 28 patients demonstrated a reduction in the size of the herniation, and
the mean reduction rate of the C-H ratio was 59%. In 4 patients, the LDH had not resolved on
MRI, but the symptoms had diminished to such an extent that surgery was not required. The
mean VAS score had significantly decreased at T1 and showed a continued decrease at the
time of the last follow-up (P < 0.001).
Limitations: This is a retrospective study and only offers data for patients who chose not to
undergo surgery. In addition, the timing of repeat MRI was not standardized.
Conclusion: The majority of cases of massive LDH demonstrated resolution at variable points
between 3 and 21 months. TFESI could provide effective pain relief for patients with massive
LDH in the interval without severe neurologic deterioration.
IRB approval: Kangdong Sacred Heart Hospital: IRB Number # 14-1-10
Key words: Lumbar disc herniation, magnetic resonance imaging, migration, regression,
resorption, sequestration, transforaminal epidural steroid injection
Calcitonin as an Additive to Local Anesthetic
and Steroid Injection Using a Modified
Coronoid Approach in Trigeminal Neuralgia
Authors: Amr Yasser Mohamed
Published: February 2021

Background: Pharmacotherapy is the main treatment for management of trigeminal
neuralgia. However, many patients become refractory to drugs.
Objectives: The present study aimed to evaluate the effect of adding calcitonin to local
anesthetic and methylprednisolone using a modified coronoid approach in management of
trigeminal neuralgia pain involving the mandibular and/or maxillary branches.
Study Design: Randomized double blind clinical trial.
Setting: Hospital outpatient setting.
Methods: Thirty-three patients received maxillary and mandibular blocks by a modified
coronoid approach. Patients were allocated into 2 groups. Group 1 received a block with
3 mL of lidocaine 0.5% plus 40 mg of methylprednisolone and another syringe contained
1 mL of 0.9% saline. Group 2 received a block with 3 mL of lidocaine 0.5% plus 40 mg of
methylprednisolone and another syringe contained 50 international units of calcitonin. Pain
was evaluated by visual analog scale (VAS) before the block (basal), at 2 weeks, one month
after the procedure, and monthly for one year. Duration of the effective pain relief of the first
block (VAS ≤ 3) was reported. Repeated blockade was allowed for any patient reporting a
VAS > 30 mm during one year of follow-up and the number of blocks were reported. Adverse
effects were also reported.
Results: A significantly longer duration of effective pain relief was noticed in group
2 compared with group 1 (P < 0.0004) while the duration of effective pain relief of the
second block in group 1 was 28.5 ± 8.9 weeks. Four patients did not need repeated blocks in
group 1 versus 15 in group 2. Six patients received 2 blocks versus 2 patients in each group,
respectively. Moreover, 6 patients needed 3 blocks in group1 versus none in group 2. No
serious adverse events were reported during or after the interventional procedure. VAS was
comparable in both groups (P > 0.05).
Limitations: Small sample size.
Conclusion: Calcitonin may be a useful additive to local anesthetic and steroid in
management of trigeminal neuralgia. Also, a modified coronoid approach for maxillary and
mandibular nerve is simple, free of radiation, safe, and may be an effective percutaneous
procedure in trigeminal neuralgia.
Key words: Calcitonine, modifed, coronoid approach, trigeminal neuralgia
Occipital Neuromodulation: A Surgical
Technique with Reduced Complications
Authors: Pagani-Estévez Gabriel L
Published: February 2021

Background: Occipital neuromodulation is a promising treatment modality for refractory
headache, but lead migration remains a frequent surgical complication.
Objectives: The primary objective was to identify surgical techniques that may minimize
adverse events, particularly lead migration. We hypothesized that a surgical technique
employing 2-point anchoring of stimulator leads designed to provide a tension-relief loop
and the use of ultrasound for lead placement would decrease the complication rate.
Study Design and Setting: A retrospective analysis was performed through electronic
medical record chart review in a tertiary referral center.
Methods: Institutional Review Board (IRB) approval was obtained. Eighteen patients had a
trial and subsequent permanent occipital nerve stimulator (ONS) implantation between 2004
and 2011 and were included. Adverse events were recorded and efficacy outcome variables
analyzed for significance.
Results: The cohort was a median (IQR) 45 (37 – 58) in age and 9 (50%) were women.
Tension-relief loops placed via a 2-point anchoring technique and ultrasound use for occipital
lead placement were evident in 16 (89%) and 13 (72%), respectively. There was one (6%)
clinically insignificant lead position change, not definitively a lead migration, which could
have been an artifact of fluoroscope positioning. Adverse events included one (6%) battery
malfunction, one (6%) lead malfunction, and 2 (12%) post-implantation infections. Following
ONS, there were significant reductions in numeric rating scale (NRS) pain scores from a median
(IQR) of 9.5 (8.25 – 10) to 2.5 (1 – 4.75) (P < 0.0001), headache days per week from 7 (7 –
7) to 1.5 (0.375 – 1.75) (P = 0.0005), and the number of daily headache medication from 3
(2.25 – 4) to 2.5 (2 – 3.75) (P = 0.0112).
Limitations: Limitations include retrospective study design, investigator bias, and nonstandardized intervals of headache burden assessment.
Conclusions: In ONS, utilization of a 2-point anchoring technique with a tension-relief loop
may significantly minimize the risk of lead migration, based on the absence of definitive lead
migration in our series. Ultrasound use may improve the anatomic accuracy of lead placement
with the possibility of improved efficacy. ONS was associated with significantly decreased
headache pain, frequency, and medication use.
Key words: Occipital neuromodulation, occipital nerve stimulation, surgical technique, lead
migration, tension-relief loop
Effectiveness and Impact of Capsaicin 8% Patch
on Quality of Life in Patients with Lumbosacral
Pain: An Open-label Study
Authors: Zis Panagiotis
Published: February 2021

Background: Capsaicin 8% patch (Qutenza™) is mainly used to treat postherpetic
neuralgia and HIV-associated neuropathy. Evidence of the efficacy of Qutenza in other forms
of neuropathic pain is lacking.
Objective: To evaluate the analgesic effect and the impact on quality of life after a single
application of the capsaicin 8% cutaneous patch in patients with lumbosacral pain.
Study Design: Prospective open-label study of capsaicin 8% patch in patients with
lumbosacral pain.
Setting: Outpatient Pain and Palliative Care Center.
Methods: All recruited patients were evaluated prior to capsaicin 8% patch administration
and were followed-up at 2 weeks, at 8 weeks, and at 12 weeks post administration. Visual
analog scale (VAS) was used to record pain intensity and EQ-5D was used to assess the quality
of life of the participants.
Results: Ninety patients met our inclusion criteria (54.4% men, mean age 59.1 ± 9.2 years).
At baseline the mean VAS score of the participants was 7.6 ± 0.7. A statistically significant
reduction of the VAS score between baseline and week 2 (mean VAS score 5.6 ± 1.1, P <
0.001) was observed. The therapeutic effect further continued between week 2 and week
8 (mean VAS score 3.2 ± 1.2, P < 0.001) and between week 8 and at endpoint at week 12
(mean VAS score 2.6 ± 1.1, P < 0.001).
Between baseline and weeks 2, 8, and 12 (end-point) a significant improvement in all 5
dimensions of EQ-5D (mobility, self-care, usual activities, pain/discomfort, and anxiety/
depression) was observed (P < 0.001)
Limitations: As it is an open-label study, a prospective randomized placebo-controlled
study should be designed to confirm the effectiveness of capsaicin 8% patch in patients with
lumbosacral pain.
Conclusions: Administration of the capsaicin 8% patch resulted in a significant relief
of neuropathic pain and a significant improvement of the quality of life of patients with
lumbosacral neuropathic pain.
Key words: Lumbosacral pain, peripheral pain, Qutenza, neuropathic pain, capsaicin, patch,
quality of life, effectiveness
Currently Recommended TON Injectate
Volumes Concomitantly Block the GON: Clinical
Implications for Managing Cervicogenic Headache
Authors: Wahezi Sayed Emal
Published: February 2021

Background: Headache (HA) is a significant cause of morbidity globally. Despite many available
treatment options, HAs that are refractory to conservative management can be challenging
to treat. Third occipital nerve (TON) and greater occipital nerve (GON) irritation are potential
etiologic agents of primary and cervicogenic HAs that can be targeted using minimally invasive
treatment options such as nerve blocks or radiofrequency ablation. However, a substantial
number of patients that undergo radiofrequency ablation do not experience pain relief despite
a positive diagnostic medial branch block (MBB).
Objective: In this study, we investigate the underlying cause for the high rate of false positives
associated with MBBs by evaluating injectate spread in cadaveric subjects.
Study Design: Cadaveric study.
Setting: Academic medical center.
Methods: After obtaining exemption status from our Institutional Review Board, TON injections
were performed on 5 preserved cadavers, a total of 10 TONs, using anatomic landmarks, partial
dissection, and palpation to guide needle placement. Cadaveric dissections were performed to
evaluate the location, vertical spread, and grossly observed injectate coating of the TON and
GON for each quantity of methylene blue injectate, 0.3 mL and 0.5 mL, administered.
Results: The average distance between the TON and GON at their respective foraminal exit
points was 1.81 cm. The average vertical spread for 0.3 mL and 0.5 mL of methylene blue
injectate was 2.02 + 0.35 cm and 3.26 + 0.48 cm when performing a TON block. When using
0.3 mL injectate, both the TON and GON were simultaneously coated 60% of the time. After
increasing the injectate volume to 0.5 mL, both the TON and GON were simultaneously coated
100% of the time.
Limitations: The cadaveric design of this study presents limitations when translating cadaveric
findings to the clinical setting. Also, the small sample size limits its power and generalizability.
Lastly, the potential for researcher bias exists as the investigators were not blinded.
Conclusions: This study demonstrates that currently recommended injectate volumes for TON
blocks may result in concomitant coating of the GON. Conventional radiofrequency ablation
(RFA) of these nerves may not lesion both the TON and GON given its restrictive circumferential
lesioning diameter of 5 – 7 mm. As such, interventionalists should consider performing
radiofrequency ablation to both the TON and GON after a positive TON block.
Key Words: Chronic pain, cervicogenic headache, third occipital nerve, greater occipital nerve,
injectate spread, radiofrequency ablation
Changes in Neuroglial Activity in Multiple
Spinal Segments after Caudal Epidural Pulsed
Radiofrequency in a Rat Model of Lumbar Disc
Herniation
Authors: Ahn Sang Ho
Published: February 2021

Background: Herniated lumbar discs can induce sciatica by mechanical compression and/
or chemical irritation. It was recently reported that neuroglial cellular activity after pulsed
radiofrequency (PRF) application to a single dorsal root ganglion (DRG) attenuated neuroglial
activity at the corresponding spinal dorsal horn. Recently, caudal epidural PRF has been used to
manage neuropathic pain, but evidence of molecular changes after the administration of caudal
epidural PRF to attenuate neuropathic pain is lacking, and it has not been determined whether
caudal epidural PRF affects neuroglial activity at different spinal levels.
Objectives: Using immunohistochemical methods in a rat model of lumbar disc herniation, the
authors investigated the effects of caudal epidural PRF administration on pain-related behavior,
on the activations of microglia and astrocytes in spinal cord, and on the expressions of calcitonin
gene-related peptide (CGRP) and Transient receptor potential vanilloid 1(TRPV1) in the DRG at the
L3, L4, L5, L6, and S1 levels.
Study Design: Controlled animal trial.
Setting: University hospital laboratory.
Methods: Forty-five Sprague-Dawley rats were randomly assigned to a sham-operated group
(n = 10) or a nucleus pulposus (NP)-exposed group (n = 35). Rats in the NP-exposed group were
further subdivided into a NP-exposed with sham stimulation group (the NP-nonPRF group; n = 13)
or a NP exposed with caudal epidural PRF stimulation group (the NP-PRF group; n = 22). Pulsed
radiofrequency was administered on postoperative day 10 (POD 10) by placing an electrode in
the caudal epidural space through the sacral hiatus and administering 5 Hz of PRF current for 600
seconds (maximum tip temperature 42°C). Rats were tested for mechanical allodynia on POD 10
and on days 7 and 14 after caudal epidural PRF administration (post-PRF). At 14 days post-PRF,
sections of the spinal cord from L3, L4, L5, L6, and S1 were immunostained for ionized calciumbinding adapter molecule 1 (Iba1) and glial fibrillary acidic protein (GFAP), and DRGs from the same
levels were immunostained for CGRP and TRPV1.
Results: Mechanical withdrawal thresholds increased at 7 days post-PRF (P = 0.04), and the
immunohistochemical expression of Iba1 in the L5 spinal dorsal horn and of CGRP in the L5 DRG
were quantitatively reduced (P < 0.001) at 14 days post-PRF. Furthermore, the upregulations of
Iba1 at L3, L4, L6, and S1 dorsal horns and CGRP at L6 DRG were also attenuated by caudal
epidural PRF (P < 0.001).
Limitation: We examined molecular changes only in ipsilateral lumbar regions and at 14 days
post-PRF.
Conclusion: Caudal epidural PRF reduced mechanical allodynia and downregulated microglia
activity and CGRP expression at the lumbar disc herniated level and in adjacent lumbar spinal levels
in a rat model of lumbar disc herniation.
Key words: Caudal, pulsed radiofrequency, multisegmental, lumbar disc herniation, microglia,
calcitonin gene-related peptide