Medical
Communication
Biosci. Biotech. Res. Comm. 10(2): 148-154 (2017)
Comparative studies on the success level of sonographic
guided epidural steroid injection and its effectiveness with
uoroscopy techniques in treating lumbar radicular pain
Alireza Gelinimoghaddam, Masoud Hashemi*, Payman Dadkhah and Mehrdad Taheri
Department of Anesthesiology and Pain, Shahid Beheshti University of Medical Sciences, Tehran, Iran
ABSTRACT
Limitations of using uoroscopic guidance in epidural steroid injection have encouraged the researchers to look for
an appropriate alternative method. Compared to uoroscopy, sonography has exceptional properties that have made
it a useful method. The present research seeks to study the success of sonographic guided epidural steroid injection
and compare its effectiveness with uoroscopy in treating lumbar radicular pain.This is a single-blind, randomized
research conducted on 50 patients complaining about lumbar radicular pain. The participants were then randomly
divided into two therapeutic groups consisting of 25 people: sonographic guided and uoroscopy guided groups. The
initial examination recorded the demographic information of each patient in his pro le. The pain scale and perform-
ance disability and therapeutic satisfaction of each patient were measured 48 hours and 2 weeks after intervention
and analyzed using statistical tests. The patients studied aged from 23 to 70 years (with an average of 45.74 ± 16.02
years) and were divided equally between the two groups in terms of gender. There was no statistically signi cant
difference between the two groups in terms of contrast matter distribution, but the average injection procedure in
sonography group (101.22 ± 36.48 s) was signi cantly faster than what was observed in uoroscopy group (311.46
± 52.13 s) (P-value < 0.05). There was no statistically signi cant difference between the two groups in terms of pain
variable, performance disability and patients’ satisfaction (P-value > 0.05). There was no statistically signi cant cor-
relation between gender and BMI with pain and performance disability in any one of these groups.The results have
shown that sonographic and uoroscopic tools have equal capabilities in epidural steroid injection. The superiority
of sonography to uoroscopy have made it possible to use this technique for epidural steroid injection.
KEY WORDS: SONOGRAPHY, FLUOROSCOPY, EPIDURAL, STEROID, LUMBAR RADICULAR PAIN
148
ARTICLE INFORMATION:
*Corresponding Author: hashemimasoud@gmail.com
Received 10
th
May, 2017
Accepted after revision 11
th
June, 2017
BBRC Print ISSN: 0974-6455
Online ISSN: 2321-4007 CODEN: USA BBRCBA
Thomson Reuters ISI ESC and Crossref Indexed Journal
NAAS Journal Score 2017: 4.31 Cosmos IF : 4.006
© A Society of Science and Nature Publication, 2017. All rights
reserved.
Online Contents Available at: http//www.bbrc.in/
Alireza Gelinimoghaddam et al.
INTRODUCTION
Backache is the most common cause of limitations
among people above the age of 45 in modern societies
(Kozinoga et al., 2015). Backache is usually observed
among the middle-aged people with women being
more prone to it. The prevalence of backache among
the elderly is reported to be 84% (Balague et al., 2012).
Radicular pains are usually the result of nerve root
in ammation or, sometimes, take place without mechan-
ical stimulation (Chang et al., 2017). One of the major
complications caused by intervertebral disc herniation
is the epidural space and nerve roots in ammation. As
clinical studies indicate, radicular pain caused by nerve
root in ammation in epidural space is the result of disk
leakage, pressure on nerve root arteries or stimulation
of dorsal root ganglia due to spinal stenosis (Chang
et al., 2017).
As radicular backache may be caused by epidural
space and nerve root in ammation, the mechanism of
in ammation suppression and repression by steroid
medicines is largely used to treat this complication (Di
Donato et al., 2010). Steroids are powerful anti-in am-
matory medicines that reduce the in ammation caused
in nerve roots by disk herniation or other pathologies in
epidural space. Various studies conducted in this eld
have con rmed the effectiveness of epidural steroid
injection in reducing the acute in ammation of nerve
roots. In comparison to oral steroids, the superiority of
epidural steroid injection lies in using lower amounts
of medicines limited to the areas of the damaged nerve
roots and reduced possibility of these medicines’ side
effects (Nampiaparampil et al., 2012). Radicular pain
and backache relief, better cooperation of patient in
physiotherapy, improved life quality, less consumption
of analgesics and improved performance of the patient
are some advantages of lumbar epidural steroid injec-
tion (Kurgansky et al., 2016). Although steroid epidural
injections are largely used to reduce and control radicu-
lar pain, we should never forget the complication of this
method including spinal cord infarction, hypertrophy of
fat, menstrual changes and adrenal suppression (Bagheri
et al., 2015, Brinks et al., 2010 Sehmbi et al., 2017).
Epidural steroid injection is a lumbar disk closed
surgery method with various cognitive and therapeu-
tic advantages. In cognitive terms, analgesia following
local anesthetics injection to epidural space and the site
of possible damage highlights the role of epidural space
as the potential source of pain. Furthermore, the long
term pain relief of the patient for several weeks follow-
ing injection indicates existence of an in ammatory
component in patient’s pain and highlights the role of
injection in reduction of this in ammatory procedure
(White et al., 1980).
Fluoroscopy guided lumbar disk closed surgery is the
method currently used for this complication. Studies
have shown that injection is carried out in the wrong
are in 30% of the cases with no uoroscopy and contrast
con rmation (Manchikanti et al., 2004). High resolution
of linear probe, harmonic imaging of tissue, two dimen-
sional matrix probe technology, imaging with a wider
viewing area, and duppler sonography power are some
advantages of sonography in comparison with uoros-
copy. These advantages have turned ultrasound into a
superior tool for analyzing skeletal-muscular disease.
Previous studies have described sonography-guided
caudal epidural steroid injection with an accuracy equal
to uoroscopy and with advantages such as the simplic-
ity of this technique and refraining from being exposed
to radiation (Park et al., 2013).
Current available researches conducted in this eld
are focused on measuring the correct placement of nee-
dle in caudal epidural space with no evidences presented
concerning sonography-guided epidural injection and it
has never been compared with uoroscopy. Considering
the constraints and limitations of uoroscopy such as
ionizing radiation and reduction of injection side effects
such as random intravenous injection, researchers are
looking for a better alternative for uoroscopy. High
resolution of probe, harmonic imaging of tissue, two
dimensional matrix probe technology, imaging with a
wider viewing area, higher pace, and the greater ease of
injection are some advantages of sonography in com-
parison with uoroscopy. These advantages have turned
ultrasound into a superior tool for analyzing skeletal-
muscular disease. Considering the potential of ultra-
sound technique, the present research seeks to study
the success level of sonography-guided epidural steroid
injection and compare its effectiveness with uoroscopy
in treating lumbar radicular pain through a single-blind,
randomized, clinical trial.
MATERIAL AND METHODS
This is a clinical trial research. In a period of three
months, as many as 50 patients aging 23 to 70 suffer-
ing from lumbar radicular pain whose diagnosis was
con rmed through clinical les, medical examination
results and electromyographic tests or were diagnosed
with disk herniation or spinal stenosis in CTScan or MRI
took part in the research. With due observation of medi-
cal ethics principles and after obtaining the consent of
patients and making them aware of the research proc-
ess, the participants took part in the research voluntar-
ily. Systematic in ammatory diseases, treatment using
anticoagulants, uncontrolled diabetes, history of allergic
reaction to contrast material, diagnosed infection, der-
mal defects in the injected area, mental problems, history
BIOSCIENCE BIOTECHNOLOGY RESEARCH COMMUNICATIONS COMPARATIVE STUDIES ON THE SUCCESS LEVEL OF SONOGRAPHIC GUIDED EPIDURAL STEROID INJECTION 149
Alireza Gelinimoghaddam et al.
of injection or surgery within the last three months, need
for non-steroid analgesics were exclusion criteria. The
initial examinations recorded the demographic infor-
mation of patients such their age, gender, height, and
BMI. Visual analogue scale (VAS) and Oswestry disabil-
ity index (ODI) questionnaires were completed by each
patient. The patients were randomly and consecutively
divided into two groups of sonography and uoroscopy
each consisting of 25 people. All patients assumed a
prone position and the area was disinfected using alco-
hol solution. Dye contrast material was injected through
sonography or uoroscopy guide and after con rming
standard contrast distribution pattern, 8 milliliter con-
taining 80 mg triamcinolone (40 mg if the patient had
diabetes), 2 milliliter of 0.5% Marcaine and up to 8 mil-
liliter sterilized N.S solution was injected to the patient.
Sonography group: after anesthetizing the injection
area, No. 18 Tuohy epidural needle was inserted through
sonographic guide and scanning in parasagittal oblique
view in accordance with in plane principles. Immediately
after insertion of the needle into Ligamentum avum,
an auto-detect syringe was attached to the needle and
inserted to the epidural space through LOR technique. To
assure the correct placement in the post-injection are of
1-2 mm of contrast material, some images were captured
in the lateral view. Having con rmed the standard dis-
tribution pattern, medicines with the above-mentioned
combinations were injected in the area.
In uoroscopy group: images were captured of the
standard AP and lateral views. LOR technique was
utilized to get to epidural space and paint using the
contrast material. Having con rmed the standard dis-
tribution pattern, medicine with the above-mentioned
mixture was injected in the area.
The present research studied the pattern of contrast
distribution in terms of lling epidural space with con-
trast material. The length of injection time since the rst
imaging until the end of injection period was measured
and recorded using a chronometer. The complications
observed during the intervention such as vasovagal
intervention, ashing or sudden lumbar pains within
a few minutes following the injection were recorded
in patients’ pro le. All injections and interventions in
sonography group were conducted by a professional
using x-porte Sonosite sonography machine, c35xp
high-frequency curve probe and Episure autodetect LOR
syringe. In uoroscopy group, ECORAY C-arm uoros-
copy X-ray systems was used to undertake epidural pro-
cedure. All patients were examined within 48 hours (T-1)
and two weeks (T-2) following intervention in terms of
fever, headache, hematoma, diabetes, high blood pres-
sure, and passing pain. VAS was the most widely used
pain measurement tool and ODI was set as the golden
standard to assess the degree of disability and estimate
the life quality of the patient suffering from backache.
Pain levels of each patient were measured prior to pro-
cedure (T-0) and within 48 hours (T-1) and 2 weeks
(T-2) after intervention using VAS and ODI scales and
the measurements were analyzed using Mann Whitney
U statistical test. To study patients’ level of satisfaction
within 48 hours (T-1) and 2 weeks (T-2) following the
intervention, a questionnaire containing a ve-option
scale was utilized where 1 indicated dissatisfaction and
5 showed maximum satisfaction.
VAS: this scale consists of a 100-mm at horizontal
line with one end titled “no pain” and the other side
titled “the worst pain possible”. The patients mark the
pain scale they often feel on a 100-mm continuum of
this at line.
ODI questionnaire: this questionnaire includes 10
topics concerning pain levels, lifting objects, ability to
take care of oneself, ability to walk, sexual performance,
ability to stand, social life, sleep quality, and ability to
go on a trip and each topic consists of 6 alternatives. The
patients selected the option that most resembled their
status (0 indicating very limited disability and 5 indicat-
ing highest level of disability) and the total scores were
added up and multiplied by two (ranging from 0 to 100)
where 0 indicated the lowest level of ability and 100
showed maximum ability. To study satisfaction level,
a ve-scale questionnaire was used with 1 indicating
dissatisfaction and 5 showing maximum satisfaction.
To make the research blind and prevent possible bias,
radiologic images were simultaneously examined and
studied by radiologists out of research and another phy-
sician not aware of injection method.
The resulting raw data was analyzed using IBM SPSS
statistics v.23 and Kolmogorov-Smirnov Test was used
to study the normality of all data and proper statistical
tests were used in accordance with the normality status.
Chi-square, Mann Whitney U and Spearman correlation
tests were used to analyze the data. The level of statisti-
cal signi cance (P-value) in this research was set to less
than 0.05.
RESULTS AND DISCUSSION
As many as 50 patients suffering from lumbar radicu-
lar pain participated in this research and were randomly
divided into sonography-guided and uoroscopy-guided
groups each consisting of 25 people. The patients’ age
ranged from 23 to 70 years old (45.74 ± 16.02 years)
and they were divided randomly in terms of their age in
both groups (Figure 1). Other demographic information
is presented in table 1.
Contrast distribution pattern of both groups was
studied in terms of lling epidural space using con-
trast material and the length of injection procedure and
150 COMPARATIVE STUDIES ON THE SUCCESS LEVEL OF SONOGRAPHIC GUIDED EPIDURAL STEROID INJECTION BIOSCIENCE BIOTECHNOLOGY RESEARCH COMMUNICATIONS
Alireza Gelinimoghaddam et al.
BIOSCIENCE BIOTECHNOLOGY RESEARCH COMMUNICATIONS COMPARATIVE STUDIES ON THE SUCCESS LEVEL OF SONOGRAPHIC GUIDED EPIDURAL STEROID INJECTION 151
FIGURE 1. The gender frequency of individuals in both groups.
FIGURE 2. Contrast distribution pattern in both groups.
Table 1. Demographic information of the patients participating in the research
Variables Minimum Maximum Mean SD
Age (year) 23.00 70.00 45.74 16.02
Height (cm) 140.00 188.00 161.26 12.60
Weight (kg) 45.00 92.00 69.88 12.73
BMI 18.73 36.73 26.84 3.78
the resulting data was recorded. Chi-square and Mann
Whitney U tests were used to analyze contrast distribu-
tion pattern and injection procedure length respectively.
The results showed contrast distribution pattern in both
groups was completely similar. In both groups, there
were 24 standard compatible contrast distribution pat-
terns and only 1 non-compatible pattern (Figure 2). As
a result, there was no statistically signi cant difference
between the two groups in terms of contrast distribution
pattern (P-value > 0.05). The average lengths of injec-
tion procedure in both groups were completely different.
The injection procedure in sonography group had an
Alireza Gelinimoghaddam et al.
152 COMPARATIVE STUDIES ON THE SUCCESS LEVEL OF SONOGRAPHIC GUIDED EPIDURAL STEROID INJECTION BIOSCIENCE BIOTECHNOLOGY RESEARCH COMMUNICATIONS
Table 2. Statistical details of contrast distribution pattern and the length of injection procedure in
groups studied
Groups
df P-Value
Ultrasound Fluoroscopy
Distribution
Standard compatible
24 24
1 1.000
Non-compatible
11
Total
25 25
Groups
Ultrasound Fluoroscopy
Variables Min Max Mean SD Min Max Mean SD P-Value
Duration (s) 60 180 101.36 22.48 216 400 311.52 46.13 0.000
Table 3. A comparison of VAS and ODI before the procedure (T-0), within 48 hours (T-1) and two weeks (T-2)
following intervention in both groups
Variables Min Max Mean SD Min Max Mean SD P-Value
VAS_0 4 10 7.52 1.38 6 9 7.20 0.86 0.248
ODI_0 42 88 67.28 12.48 50 88 71.84 9.62 0.167
VAS_1 2 8 3.88 1.26 2 8 3.76 1.12 0.544
ODI_1 20 80 37.92 12.07 26 82 40.56 10.97 0.220
VAS_2 2 8 3.12 1.36 2 8 3.00 1.19 0.827
ODI_2 20 80 30 12.27 20 80 32.48 11.52 0.187
average length of 101.22 ± 36.48 s, while this procedure
in the other group lasted 311.46 ± 52.13 s (P-value <
0.05) (Table 2).
The information collected from the participating
groups concerning VAS and ODI prior to procedure
(T-0) and within 48 hours (T-1) and 2 weeks (T-2) after
intervention and patients’ satisfaction levels in both
groups within 48 hours (T-1) and two weeks (T-2) after
intervention were collected using a questionnaire with
a 5-alternative scale and analyzed using Mann Whit-
ney U test. The results of these statistical tests failed to
nd any statistically signi cant difference between the
two groups in terms of these variables (P-value > 0.05).
The performance of sonography and uoroscopy meth-
ods had no signi cant in uence on VAS and ODI and
patients’ satisfaction (Tables 3 & 4).
The present research also studied the effect of age,
gender and BMI on VAS and ODI within 48 hours (T-1)
and two weeks (T-2) following epidural steroid injec-
tion under sonography and uoroscopy guidance.
The results found a statistically signi cant correlation
between age and VAS and ODI within two weeks after
intervention (ODI_2 & VAS_2) in sonography group and
ODI_2 in uoroscopy group (P-value < 0.05). As the
age grew older and older, the level of these variables
also increased (in other words, the post-procedure pain
reduction and performance power of the patients would
increase in older ages). There was no statistically signi -
cant correlation between sex and BMI with VAS and ODI
within 48 hours (T-1) and two weeks (T-2) after epidural
steroid injection (P-value > 0.05) (Table 5).
Spinal disk bulging and degenerative narrowing of spi-
nal canal are two major causes of radicular lumbar pains
(Cyteval et al., 2006). Laboratory documents have pointed
to in ammation of nerve roots as the mechanism of caus-
ing pain (Ghahreman et al., 2010). Experts have recom-
mended injection of steroids in epidural space in order to
reduce pain and in ammation. Fluoroscopy guidance is
the method used for injection in epidural space which has
countless limitations and dangers. Considering the high
Table 4. Comparing levels of patients’ satisfaction within 48 hours (T-1) and two weeks (T-2) following intervention in
both groups
Variables Min Max Mean SD Min Max Mean SD P-Value
Satisfaction-1 1 5 4.48 0.91 1 5 4.56 0.86 0.717
Satisfaction-2 1 5 4.52 0.962 1 5 4.64 0.86 0.667
Alireza Gelinimoghaddam et al.
BIOSCIENCE BIOTECHNOLOGY RESEARCH COMMUNICATIONS COMPARATIVE STUDIES ON THE SUCCESS LEVEL OF SONOGRAPHIC GUIDED EPIDURAL STEROID INJECTION 153
potential and unique properties of ultrasound method
compared with uoroscopy, this tool can be considered
a good alternative for uoroscopy. The present research
sought to compare sonography- and uoroscopy-guided
epidural steroid injection in radicular lumbar pain.
Although no similar researches were found in our review
of literature, there are similar and comparable researches
in this eld whose results can be compared with those of
the current study. A research was conducted on ef ciency
of caudal epidural injection guided by ultrasound by Nik-
ooseresht et al in 2014.
They studied as many as 240 patients suffering from
sciatica backache. Epidurogram con rmed the success of
230 cases out of 240 injections (95.8%). They arrived at
the conclusion that ultrasound is a safe, quick and reli-
able method to assess various variations of Sacral hiatus
and, also, epidural injection (Nikooseresht et al., 2014).
Yoon et al (2005) studied the effectiveness of ultrasound
duppler and uoroscopy in nding intravascular ow in
order to con rm placement of needle in epidural cau-
dal space among 53 patients suffering from backache
and sciatica. The medicine was injected successfully into
epidural caudal space through sonography in 52 people.
They concluded that sonography was a reliable imag-
ing method for caudal epidural steroid injection. What’s
more, its advantages such as the ease and no risk of
ionization radiation turn it to a more appropriate choice
than uoroscopy (Yoon et al., 2005). Another research
conducted by Chen et al studied the correct perform-
ance of ultrasound in locating sacral hiatus and guiding
the needle to caudal epidural space in the kidneys of
70 patients. Sacral hiatus was located carefully using
ultrasound in all patients and epidural caudal needle
was successfully guided to the epidural space. The accu-
racy of needle placement in epidural space as directed
by ultrasound was con rmed by injection of contrast
material and uoroscopy (Chen et al., 2004).
The results of the researches conducted by Nik-
ooseresht, Yoon and Chen are completely in line with
those achieved in the present study. The only differ-
ence between these studies and those of our research
lies in the site of injection. Our study was based on a
new approach and investigated sonography-guided ster-
oid injection procedure to the epidural space while they
carried out this research in epidural caudal space. Ober-
nauer et al studied factors such as accuracy, time, radia-
tion level, safety and pain reduction in ultrasound- and
CT scan-guided pre-radicular injection and compared
them against one another. The results of this research
conducted on 40 patients con rmed the 100% accuracy
of ultrasound-guided intervention. The average length
of needle placement in sonography was 2:21 minutes,
while this length in CT Scan-guided method was 10:33
minutes. Both groups showed a similar reduction in
pain levels and no difference was observed between the
techniques in such terms. They nally arrived at the
conclusion that ultrasound-guided pre-radicular injec-
tion has an equal therapeutic accuracy and ef ciency
than CT scan guidance. This procedure requires a shorter
time and has no risk of ionization ray (Obernauer et al.,
2013).
Although this procedure is completely different from
our procedure, the results they have achieved (no differ-
ence in therapeutic ef ciency of methods and the high
speed of procedure in ultrasound method) are in line
with our research.
CONCLUSION
With reference to the results of the present research, we
may conclude that there is no difference between the
ability of sonography and uoroscopy in steroid epi-
dural injection. Considering the special advantages of
sonography such as less radiation than uoroscopy, it is
concluded that sonography can be used in steroid epi-
dural injection procedure to treat radicular pains, just
like uoroscopy.
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