Access to this full-text is provided by Springer Nature.
Content available from Trials
This content is subject to copyright. Terms and conditions apply.
S T U D Y P R O T O C O L Open Access
Caudal epidural steroid injections versus
selective nerve root blocks for single-level
lumbar spinal stenosis: a study protocol for
a randomized controlled trial
Akram Osman, Wei Hu
*
, Jianhua-Sun, Jing Li, Xiao Luo, Nianrong Han, Ehsan Abduhani and Zhenqiang Liu
Abstract
Background: Lumbar spinal stenosis (LSS) is a common degenerative condition associated with old age. Its
incidence continues to increase with the rapidly aging population in China. Treatment for LSS usually begins with
conservative treatments, as some patients refuse surgical procedures or have surgery contraindications. Caudal
epidural steroid injections (CESIs) and selective nerve root blocks (SNRBs) are two commonly used conservative
treatments for LSS, which have proven to be effective at relieving LSS symptoms in many studies. However, there
are no randomized controlled trials comparing these two procedures. We planned the first study to assess which
one of these two procedures is more effective in treating LSS. We will compare the efficacy of these two treatment
methods in terms of duration of symptom relief and recurrence rate. We hope our findings will help clinicians
choose an optimal treatment for LSS patients.
Methods/design: We plan to conduct a 1-year randomized controlled trial that will include a total of 76 subjects.
They will be randomly divided into two groups: group A (patients will receive CESIs) and group B (patients will
receive SNRBs). Two days before the procedure, we will assess these patients using the Leeds Assessment of
Neuropathic Symptoms and Signs (LANSS) pain scale, Oswestry Disability Index (ODI), and numeric rating scale
(NRS) for pain. One day, 2 weeks, 3 months, 6 months, and 1 year after the procedure, we will assess the condition
of these patients again with the NRS and ODI.
Discussion: We hope our findings will lay the foundation for the design of further comprehensive studies and help
clinicians make a choice between CESIs and SNRBs for LSS patients.
Trial registration: Chinese Clinical Trial Registry ChiCTR1900028038. Registered on 8 December 2019
Keywords: Caudal epidural steroid injections, Selective nerve root blocks, Lumbar spinal stenosis, Randomized
controlled trial
© The Author(s). 2021 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License,
which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give
appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if
changes were made. The images or other third party material in this article are included in the article's Creative Commons
licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons
licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain
permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the
data made available in this article, unless otherwise stated in a credit line to the data.
* Correspondence: realhuwei@163.com
The Second Spine Department of the Fourth School of Clinical Medicine of
Xinjiang Medical University, Spine Department of the First Affiliated Hospital
of Shihezi University, Shihezi, China
Osman et al. Trials (2021) 22:524
https://doi.org/10.1186/s13063-021-05485-1
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
Background
Lumbar spinal stenosis (LSS) is a lower back condition
where the central canal, lateral recess, or neural foram-
ina becomes narrowed. Common LSS symptoms are
lower back pain, burning pain in the buttocks or legs,
weakness, numbness or tingling, and loss of sensation
[1]. However, some people with LSS may be asymptom-
atic. Other patients may have to lean forward to relieve
pain while walking, but physical examination often fails
to find positive signs [2]. LSS is typically caused by de-
generative arthritis, and less common causes include
space-occupying lesions and fibrosis. The prevalence of
LSS is estimated to be 47.2%, and its classical symptoms
are neurogenic claudication and lower back pain [3].
Given that the causes of LSS tend to differ among dif-
ferent patients, doctors need to determine how and why
a patient develops LSS in order to formulate a treatment
plan that works best for him/her. The main pathogenesis
of LSS is inflammatory changes around the nerve roots,
congestion, and edema, which is also an important cause
of root pain and the theoretical basis for corticosteroid
injection to improve clinical symptoms [4–6]. Ma et al.
believed that long-term inflammation, chronic strain,
ligamentum flavum, and facet hypertrophy reduce the
normal space available for nerves in the spinal canal and
result in direct pressure on nerve roots causing lower
back pain [7]. Chagnas et al. pointed out that LSS is sec-
ondary to facet joint osteoarthritis, ligamentum flavum
hypertrophy, and/or bulging of the intervertebral disc
that leads to narrowing of the spaces around neurovas-
cular structures of the spine [8].
To provide a scoring system that can guide LSS treat-
ment and based on the pathogenesis and imaging charac-
teristics of LSS, researchers have proposed the following
grading system: grade 0—a normal intervertebral foramen;
grade 1—mild foraminal stenosis with perineural fat oblit-
eration in either the transverse or vertical direction; grade
2—moderate foraminal stenosis with perineural fat oblit-
eration in both the transverse and vertical directions; and
grade 3—severe foraminal stenosis with nerve root col-
lapse or morphologic change [9,10].
Most patients seeking treatment for lower back pain
have LSS. Treatments for LSS can be conservative and
surgical. Conservative management is successful in most
patients and is recommended as first-line treatment.
Common conservative treatments for LSS include caudal
epidural steroid injections (CESIs) and selective nerve
root blocks (SNRBs). The reasons for their popularity
among primary care physicians are as follows: First,
compared with conventional surgical interventions,
SNRBs and CESIs greatly reduce the time that physi-
cians are exposed to X-rays, thus protecting their health.
Second, SNRBs and CESIs are easy to perform and have
a short learning curve.
The efficacy of CESIs has been demonstrated in many
studies. Delport et al. analyzed 140 patients treated with
epidural steroid injection (ESI) [11]. Fifty-three percent
reported improvement in their functional abilities and
74% were at least somewhat satisfied with ESI as a form
of treatment. Fukusaki et al. conducted a prospective,
randomized, double-masked trial evaluating the efficacy
of ESI in 53 patients with LSS [12]. The patients were
randomized into three groups: epidural saline injection,
epidural local anesthetic, and epidural anesthetic plus
steroid. They found that there was a significant differ-
ence in the efficacy of the different treatments at 1
month. However, after 3 months, there was no signifi-
cant difference between the three groups, proving the
short-term effect of ESI. Koc et al. reported findings
from a prospective, randomized controlled trial of 33 pa-
tients comparing the effects of ESI and a conservative in-
patient physical therapy program on pain and function
for patients with LSS [13]. They found that the ESI
group had significant improvement in visual analog scale
(VAS) scores at the 2-week follow-up. They concluded
that ESI and physical therapy are equally effective in
treating LSS up to 6 months of follow-up, while ESI has
better short-term efficacy.
A selective nerve root block (SNRB) is a minimally in-
vasive procedure; a needle is inserted into the epidural
space in the foramen at the suspected spinal level, and
medications such as steroids and local anesthetics are
then injected into the area of a specific nerve root [14].
This procedure is considered a very safe and effective
treatment option for spinal neuropathy and chronic back
pain [15,16]. Zhang et al. performed SNRBs in 56 LSS
patients and found that 80% of them achieved excellent
short-term surgery outcomes [17]. Weiner et al. analyzed
30 patients with herniated discs who underwent nerve
root blocks and noted immediate relief in 27 patients.
During 1–10 years of follow-up, 22 patients (79%) expe-
rienced substantial and permanent pain relief [18].
Martin et al. retrospectively analyzed 30 (20 disc hernia-
tions, 10 foraminal stenoses) patients with minor sen-
sory/motor deficits who were treated with a SNRB [19].
They found that 87% of patients had rapid and signifi-
cant regression of pain in 1–4 days, and 60% had per-
manent resolution of pain. Therefore, they believe that
SNRBs are very effective in treating lumbar neuropathy
and recommend them as the treatment of choice for this
condition.
Narrowing of the spinal canal caused by lumbar spine
degeneration usually occurs slowly, over many years or
decades. Substantial narrowing compresses the spinal
nerves, which causes symptoms including pain at the
early stage, and numbness and weakness of the extrem-
ities at the middle and late stages, severely affecting pa-
tients’quality of life. Therefore, doctors should aim for
Osman et al. Trials (2021) 22:524 Page 2 of 8
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
early-stage interventions, offer effective treatments in
the middle stage, and absolutely avoid late-stage surgery.
In addition, it is recommended that patients in need of
conservative treatments receive interventions as early as
possible to prevent exacerbation of lumbar neuropathy.
It follows from the above that both CESIs and SNRBs
can effectively relieve clinical symptoms and improve
neurologic function in patients with LSS. SNRBs are dif-
ferent from epidurals. Instead of administering medica-
tion to cover all the nerve roots, selective blocks are
performed to target a particular pinched nerve root.
SNRB injections can therefore be performed to manage
a specific area of pathology without causing damage to
nearby normal nerve tissues.
To our knowledge, however, there have been no ran-
domized controlled trials comparing the efficacy of
SNRBs and CESIs. In clinical practice, primary care phy-
sicians often have to choose between a selective nerve
block and a caudal epidural injection based on their own
experience, as there is no guideline for them to refer to.
To fill this gap, we plan to conduct the first study to
compare the effects of SNRBs and CESIs on LSS. We
will use outcome measures such as duration of symptom
relief and recurrence rate to determine whether SNRBs
or CESIs are more effective. We hope our findings will
help physicians make a choice between SNRBs and
CESIs for LSS patients.
Hypothesis
Our hypothesis is that SNRBs have a lower recurrence
rate than CESIs in treating patients with single-level
LSS.
Methods/design
This is a randomized controlled trial, aimed at compar-
ing the recurrence rate of LSS following treatment with
SNRBs and CESIs in patients with one-level LSS. This
study was approved by the Ethics Committee of the
Fourth School of Clinical Medicine of Xinjiang Medical
University and will be conducted in accordance with the
World Medical Association Declaration of Helsinki. This
study is registered in the Chinese Clinical Trial Registry
(Registration No. ChiCTR1900028038). Written in-
formed consent will be obtained from all patients before
initiating treatment.
Evaluation of the results and statistical analysis will be
performed by professionals who are blinded to the group
assignment. Participant flow is shown in Fig. 1. The
study will last for 1 year. Patients will be randomly di-
vided into two groups with patients in group A receiving
a CESI and patients in group B receiving an SNRB.
The main outcome measures include the Leeds As-
sessment of Neuropathic Symptoms and Signs (LANSS)
pain scale to determine whether the pain experienced is
due to nerve damage, the Oswestry Disability Index
Fig. 1 Schematic presentation of patient flow. LSS, lumbar spinal stenosis; CESI, caudal epidural steroid injection; SNRB, selective nerve root block;
NRS, numeric rating scale; ODI, Oswestry Disability Index; LANSS, Leeds assessment of neuropathic symptoms and signs
Osman et al. Trials (2021) 22:524 Page 3 of 8
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
(ODI) to assess functional status, and a numeric rating
scale (NRS) for pain to evaluate pain intensity [20]. Two
days before the procedure, we will assess the condition
of patients using the LANSS pain scale, ODI, and NRS
for pain. One day, 2 weeks, 3 months, 6 months, and 1
year after the procedure, we will evaluate these patients
again using the NRS for pain and the ODI.
Recruitment
First, we will assess the potential candidates and inform
them of our study procedure. We will randomly divide
the eligible patients into two groups after obtaining writ-
ten informed consent from each patient. Treatment will
be given to each patient based on the group he/she is in.
Sample size
Because the present study is a clinical application, ac-
cording to the actual situation, it is difficult to calculate
the sample size by pre-experiment, so we finally decided
that the sample size of this study was obtained from the
previous relevant literature data. The sample size out-
come effect size is based on studies found in the litera-
ture using the ODI and NRS scores [21]. The mean
change of ODI and NRS in group B is expected to be
93% and 0–1 scores, while in group A it is expected to
be 80% and 3–4 scores. The sample size was calculated
using the sample size formula for a quantitative equiva-
lence trial: n=2(Z
α
+Z
β
)
2
δ
2
/(D−Δ)
2
(α= 0.05, β=
0.2). After we entered δof 2.17, Dof 0.1, and Δof 1.2
into the formula, we found that it required 31 patients
in each group. Given a loss to follow-up rate of 20%, ap-
proximately 76 subjects are required.
This experiment was conducted simultaneously in the
Second Spine Department of the Fourth School of Clin-
ical Medicine of Xinjiang Medical University and Spine
Department of the First Affiliated Hospital of Shihezi
University, and inpatients meeting the inclusion criteria
were included in the study.
Since the LSS patient base of the above two depart-
ments is large enough to recruit subjects at the same
time, there is no need to worry about the sample size.
Some benefits can also be provided to patients partici-
pating in the study to supplement the sample size (such
as free professional counseling, functional exercise
instruction)
Inclusion, exclusion, and diagnostic criteria
The inclusion criteria are shown in Table 1. The exclu-
sion criteria are shown in Table 2. All recruited patients
who meet the diagnostic criteria for LSS will be screened
for eligibility in strict accordance with the inclusion and
exclusion criteria.
Diagnostic criteria
According to the “Clinical Guideline for the Diagnosis
and Treatment of Degenerative Lumbar Spinal Stenosis
by the North American Spine Society (NASS)”in 2011:
Degenerative lumbar spinal stenosis describes a condi-
tion in which there is diminished space available for the
neural and vascular elements in the lumbar spine sec-
ondary to degenerative changes in the spinal canal.
The main clinical symptoms include sacroiliac joint
pain and sharp radiating pain in the lateral thighs, lower
legs, and feet, as well as lower extremity numbness and
decreased muscle strength. Some patients also experi-
ence intermittent claudication. Leg pain and weakness
are precipitated by walking or standing for a long time
and relieved with forward flexion, sitting, and rest.
Magnetic resonance imaging (MRI) represents the
gold standard for the assessment of LSS: sagittal diam-
eter of the lumbar central canal, 13–15 mm (abnormal),
10–13 mm (narrow), and < 10 mm (absolute stenosis);
dural sac area, < 100 mm
2
(relative stenosis) and < 70
mm
2
(absolute stenosis).
Randomization and blinding
Dr. Jianhua Sun and Dr. Jing Li from the Spine Depart-
ment of the First Affiliated Hospital, School of Medicine,
Table 1 Inclusion criteria
1) Lumbar MRI scan shows LSS at a single level (sagittal diameter of
lumbar central canal < 13 mm; dural sac area < 100 mm
2
), with no
prolapsed or sequestered discs.
2) Recurrent intermittent claudication and unable to walk long
distances.
3) Aged 50–85 years and in need of pain relief.
4) Inflammation-induced pain.
5) Less than a 3-month history of radiating pain in the lower legs.
6) LANSS score ≥12.
MRI, magnetic resonance imaging; LSS, lumbar spinal stenosis; LANSS, Leeds
Assessment of Neuropathic Symptoms and Signs
Table 2 Exclusion criteria
1) Patients unable or unwilling to receive treatment
2) Allergic to contrast medium or drugs planned to be injected
3) Untreated local infection at the planned surgical site
4) Patients who cannot cooperate during the procedure or have a
history of mental disease
5) Pregnancy
6) Receiving anticoagulant therapy
7) Congenital or surgical anatomical diseases which affect the safety and
success of the procedure
8) Systemic infection
9) Severe respiratory or cardiovascular diseases
10) Immunosuppression
Osman et al. Trials (2021) 22:524 Page 4 of 8
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
Shihezi University, will use computer software to gener-
ate random sequences, which will be sealed in envelopes
and concealed from recruiters and subjects. Ehsan from
the Second Spine Department and investigator Akram
are responsible for recruiting eligible patients. Zhenqiang
Liu from the Second Spine Department will randomly
assign recruited patients into two groups. In this study,
we will use the single-blind approach in which the par-
ticipant is unaware of which treatment he/she is receiv-
ing. The specific procedure performed will be kept
hidden from all participants before unblinding.
We also plan to charge all subjects the same fee to en-
sure the nature of blinding. The specific fees charged are
as follows: nerve blocks 86 yuan + 2 vials of triamcino-
lone acetonide injection (40 mg/ml, Kunming Jida
Pharmaceutical Co., Ltd.), 18.98 yuan + 1 vial of lido-
caine (20 mg/ml, Hebei Tiancheng Pharmaceutical Co.,
Ltd.), and 2.62 yuan + 1 vial of Omnipaque (300 mg I/
ml, GE Healthcare, Shanghai, China) (83 yuan). The
total cost is 190.6 yuan.
Interventions
Patients will be randomly divided into two groups: group
A (patients will receive CESIs) and group B (patients will
receive SNRBs). Two days before the procedure, we will
assess the condition of patients using the LANSS pain
scale, ODI, and NRS for pain.
Technique for caudal epidural injections
The patient will be asked to lie in the prone position. A
soft pillow approximately 10 mm thick is placed under
the stomach area so that the sacrum is slightly elevated.
The sacral hiatus is identified and marked on the skin.
Following correct skin sterilization and draping, a sur-
geon will first practice inserting a 7-gauge spinal needle.
A subjective feeling of “give”and loss of resistance sug-
gests piercing the sacrococcygeal ligament.
An 18-gauge spinal needle is then introduced into the
anterior wall of the sacrum. Care is taken to ensure that
the needle shaft is at an angle of 90° to the skin surface.
Once the needle reaches the periosteum, it is tilted to-
wards the caudal vertebra and advanced upward for up
to 5 cm into the sacral canal with an angulation of 30° to
the surface. The hub of the needle is then attached to
the syringe. Loss of resistance when pushing air is char-
acteristic of entering the sacral canal. After removal of
the stylet and guidewire, and aspiration to check for
blood or cerebrospinal fluid, 0.2–0.3 ml of Omnipaque is
injected to confirm correct placement. If the contrast
agent can be seen in the epidural space as confirmed by
X-ray imaging, the needle is correctly placed. A mixture
consisting of 80 mg of triamcinolone acetonide and 2 ml
of 1% lidocaine is injected [22–24].
Technique for nerve root blocks
The patient is placed in the prone position. The affected
level is identified under C-arm guidance, and a horizon-
tal line is marked at the level of the lower edge of the
pedicle. After sterile preparation and draping, an 18-
gauge spinal needle is inserted 0.5 cm below the marked
line and 10 cm from the spinous process at an angle of
25–30° to the coronal plane and parallel to the interver-
tebral space on the axial plane. For local anesthesia, 1%
lidocaine is injected when advancing the needle. Under
C-arm guidance, the direction and depth of the needle
are observed, and it is inserted where the nerve root
exits. Anteroposterior and lateral X-ray imaging of the
lumbar spine is performed again when inserting the nee-
dle through the intervertebral foramen. On the anterior-
posterior view, the tip of the needle is placed approxi-
mately 0.5 cm beneath the corresponding pedicle. On
the lateral view, the needle tip is positioned just below
the pedicle and into 1/3 of the posterior aspect of the
intervertebral foramen. Radiating pain along the nerve
occurs if the nerve root is punctured. The patient is
asked whether this is the site he/she experienced pain.
Then, 0.2 to 0.3 ml of Omnipaque is injected into the
nerve root sheath to clearly visualize the existing nerve
root. When an adequate flow of contrast medium to the
target area occurs, a solution consisting of 80 mg of tri-
amcinolone acetonide and 2 ml of 1% lidocaine is
injected [25–27].
Data collection
We will evaluate the treatment outcomes using the NRS
and ODI 1 day, 2 weeks, 3 months, 6 months, and 1 year
after the procedure. The treatment plan and evaluation
of results are shown in Table 3.
Outcome measures
Multiple outcome measures were utilized which in-
cluded the NRS (0–10 scale) pain scale and the ODI on
a0–50 scale, with assessment at 1 day, 2 weeks, 3
months, 6 months, and 1 year after the procedure. The
Oswestry Disability Index (ODI): back pain-related dys-
function will be assessed using the ODI. The ODI con-
tains 10 questions about daily activities, including
inventories of pain intensity, personal care, lifting, walk-
ing, sitting, standing, sleeping, sexual life, social life, and
traveling. Each question is rated on a scale from 0 to 5
points; the lower the score, the less disabled the person
is by the pain. The NRS represented no pain with a 0
and the worst pain imaginable with a 10. NRS is an in-
strument for the self-assessment of pain and comprises a
scale with 0 and 10 at either end of a straight line. The
participants marked a point on the line to indicate their
level of average pain. The value and validity of the NRS
and ODI have been reported [28,29]. The main
Osman et al. Trials (2021) 22:524 Page 5 of 8
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
outcome measures of the present study were ODI and
NRS scores after follow-up and the final recurrence rate
calculated according to the requirements. ODI and NRS
scores were obtained by designated personnel after
follow-up work. After obtaining the above two scoring
data, the curative effect was evaluated according to the
requirements of Table 4, and the recurrence rate was
obtained. According to the ultimate purpose of this
study, the recurrence rate plays a very important role in
the outcome indicators. ODI and NRS also provide the
basis for the final calculation of recurrence rate, which
significantly affects the evaluation of the efficacy of each
subject, and also plays a decisive role in the research re-
sults. Specific criteria for evaluating the efficacy are
shown in Table 4.
Supervision, safety, and quality control
During the 1-year follow-up period, we will use paper
case report forms and self-reported questionnaires to
collect data. All data collection will be supervised in
strict accordance with the standard procedure of the
clinical trial center to ensure full compliance with Inter-
national Council for Harmonization (ICH) standards
and Good Clinical Practice (GCP) principles. Any pa-
tient who experiences adverse events such as worsening
of clinical symptoms and loss of ability to perform daily
activities during the study period will be fully evaluated
by doctors’inquiries, physical examination, and imaging
studies. If the adverse event is believed to be caused by
the intervention received, the treatment will be termi-
nated and the patient will be offered symptomatic treat-
ment. We will analyze relevant data on adverse events
and LSS interventions to improve treatment. All adverse
events will also be reported to the investigators. Given
the short period and low risk of our study, we did not
set up a Trial Steering Committee. Any unexpected
events will be directly reported to the investigators for
advice. There is no interim analysis was set in this proto-
col, and WH and AO will have access to decide whether
to make the final decision to terminate the trial.
For the control group and the experimental group,
other treatments allowed for the patients are as follows:
(1) both groups can be given routine nursing treatment
in Department II of Spine of Traditional Chinese Medi-
cine Hospital of Xinjiang Uygur Autonomous Region,
including daily inquiry of patients’condition, pain im-
provement, and care for patients. (2) Acupuncture and
moxibustion treatment of lumbar spinal stenosis was
performed by a doctor designated by the Acupuncture
and Moxibustion Department of the said hospital. Stan-
dardized acupuncture and moxibustion treatment of
lumbar spinal stenosis was adopted, that is, acupuncture
and moxibustion treatment was the same for all subjects.
(3) The massage treatment of lumbar spinal stenosis was
performed by the designated physician in the Depart-
ment of Massage of the said hospital. The standardized
treatment of lumbar spinal stenosis with acupuncture
and massage was used, that is, all subjects had the same
massage treatment. (4) The treatment can be performed
by the designated nurse of Department II of Spine and
ensure that all subjects are electrically treated in the
same position. The other treatments allowed are trad-
itional Chinese medicine treatment, which can play the
role of adjuvant treatment, and the two groups of pa-
tients received the same treatment. As a result, the effect
of the above treatment on the experimental results can
be avoided. For the control group and experimental
Table 3 Treatment plan and evaluation of results
Data collection/recording Person in
charge
Observational phase Follow-up phase
2 days before
intervention
1 day after
intervention
2 weeks after
intervention
3 months after
intervention
6 months after
intervention
1 year after
intervention
Obtaining informed consent Luo Xiao ×
Collecting patients’basic
information and medical history
Han Nirong ×
Screen patients for eligibility Ehsan Abduhani ×
LANSS pain scale Akram Osman ×
ODI Akram Osman
Liu Zhenqiang
××××××
NRS for pain Akram Osman
Liu Zhenqiang
××××××
LANSS, Leeds Assessment of Neuropathic Symptoms and Signs Pain Scale; ODI, Oswestry Disability Index; NRS , numeric rating scale
Table 4 Efficacy evaluation
Cured: neither CESI nor SNRB cured LSS
Marked effect: NRS score < 2 points or ODI score < 50%
Effective: NRS score 2–4 points or ODI score 50–70%
Relapse: NRS score > 4 points or ODI score > 70% or the use of
analgesics of the patient’s own choice
Note: We will record the time a patient has recurrence and stop follow-up
CESI, caudal epidural steroid injection; SNRB, selective nerve root block; LSS,
lumbar spinal stenosis; NRS, numeric rating scale; ODI, Oswestry
Disability Index
Osman et al. Trials (2021) 22:524 Page 6 of 8
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
group, the other treatments prohibited from the patients
are as follows: (1) In the course of the experiment, other
invasive treatments for lumbar spinal stenosis were per-
formed, (2) It is forbidden for the subjects to take drugs
that can improve the clinical symptoms of lumbar spinal
stenosis. (3) Patients were not allowed to receive other
treatments for lumbar spinal stenosis without the con-
sent of the researcher. (4) They took related analgesics
by themselves.
Xiao Luo, a physician of Spine Department II, had an
informed conversation with the subjects 2 days before
the operation and obtained consent from the subjects.
After Dr. Luo Xiao obtained the informed consent from
the subjects, Nianrong Han, a physician of Spine Depart-
ment II, asked the subjects for the basic information and
related medical history of the patients required for the
experiment, which was also completed 2 days before the
operation. Ehsan Abduhani, a physician of Spine Depart-
ment II, checked whether the subjects met the pre-
scribed criteria 1 day before the operation and finally
determined whether they were included in the experi-
ment. Researcher Akram Osman completed his work of
LANSS scoring 2 days before the operation after Dr. Luo
Xiao and Dr. Han Nianrong completed their work. After
then, Akram Osman and Zhengqing Liu completed the
follow-up collection of ODI and NRS. It should be noted
that for the same subject, the same person should always
follow up and collect data, which cannot be carried out
alternately. The follow-up collection of data must be
completed within 24 h on the specified date. Akram
Osman is responsible for sorting and inputting the col-
lected data into the designated data collection table and
setting the password to save independently. This work is
completed within 24 h after receiving the data.
Dropouts and loss to follow-up
All patients have the right to drop out of the study at
any time. If a patient chooses to discontinue participa-
tion, we will withdraw consent from this patient and ter-
minate the study. The chief investigator can also
terminate a subject’s participation if he/she breaks the
rules governing this study or has severe adverse events.
Data on these subjects will be excluded from our final
analysis.
Statistical methods
Two investigators will use EpiData 3.0 for data entry.
SPSS18.0 will be used to analyze all data. All patients’
demographic and clinical characteristics (e.g., gender,
age, and weight) will be subject to descriptive analysis.
Quantitative data will be expressed as mean ± standard
deviation, medians, and ranges, while qualitative data
will be expressed as frequency and percentage. A chi-
squared test will be used to compare the incidence of
adverse events between patients in the two groups.
Publication of study results
The study results will be published in relevant medical
journals. The chief investigator together with the mem-
bers of the research management team and other inves-
tigators will write the manuscript and submit it to a
journal for publication.
Discussion
Both SNRBs and CESIs have proven efficacy against LSS.
However, there are no studies comparing the effective-
ness of these two treatments in LSS. In clinical practice,
primary care physicians often have to choose between
these two procedures based on their own experience as
there is no guideline for them to refer to. Such subjectiv-
ity raises the risk of adopting a suboptimal treatment
plan for a patient, which can result in less than desirable
outcomes and increase the uncertainty surrounding the
prognosis of patients. In severe cases, treatment can fail,
increasing patients’pain and economic burden. To avoid
patients receiving inappropriate treatment, we evaluated
the effects of SNRB and CESI treatment for LSS. We will
divide recruited LSS patients into two groups and offer
them either SNRBs or CESIs. Data including duration of
symptom relief and time to relapse in patients in the
two groups will be recorded, and the recurrence rate will
be calculated to determine whether SNRBs or CESIs are
more effective in relieving patients’symptoms long term.
We hope our findings will provide a reference for physi-
cians and help them make a choice between SNRBs and
CESIs for LSS patients based on scientific and clinical
evidence so that these patients can receive optimal treat-
ment with maximal efficacy.
Trial status
The version number of this protocol is no. 3.0, date:
2020-1-28. The date of subject start recruitment is 2020-
4-16, and we expect to complete all research processes
by the end of 2021.
Abbreviations
LSS: Lumbar spinal stenosis; LANSS: Leeds Assessment of Neuropathic
Symptoms and Signs; ODI: Oswestry Disability Index; NRS: Numeric rating
scale
Acknowledgements
The Second Spine Department of the Fourth School of Clinical Medicine of
Xinjiang Medical University; Spine Department of the First Affiliated Hospital,
School of Medicine, Shihezi University.
Authors’contributions
HW and AO conceived and designed the study and wrote the manuscript.
AO and EA recruited the subjects. SJH and LJ generated the randomized
sequences and evaluated the research results. LX reminded the subjects of
matters requiring attention and obtained their informed consent. HNR
Osman et al. Trials (2021) 22:524 Page 7 of 8
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
collected and collated the data. LZQ randomly grouped the patients. All
authors have read and approved the final manuscript.
Funding
Not applicable.
Availability of data and materials
Only AO and HW will have access to the final trial dataset, and the rest are
barred from accessing the data. Any data required to support the protocol
can be supplied on request.
Declarations
Ethics approval and consent to participate
The study participants will be given their informed consent prior to
recruitment and will be included in the study after signing the informed
consent.
This study was approved by the Ethics Committee of the Fourth School of
Clinical Medicine of Xinjiang Medical University and will be conducted in
accordance with the World Medical Association Declaration of Helsinki.
If the protocol needs to be amended, all materials in the trial will be
reported to the ethics committee, and the amended protocol can be
implemented only after consent acquirement.
The data collected in this protocol will not be allowed to be used for other
purposes.
Consent for publication
Not applicable.
Competing interests
The authors declare that they have no competing interests.
Received: 6 August 2020 Accepted: 25 July 2021
References
1. Abbas J, Hamoud K, May Het al. Degenerative lumbar spinal stenosis and
lumbar spine configuration. Eur Spine J 2010;19(11):1865-1873, DOI: https://
doi.org/10.1007/s00586-010-1516-5.
2. Botwin KP, Gruber RD, Bouchlas CGet al. Fluoroscopically guided lumbar
transformational epidural steroid injections in degenerative lumbar stenosis:
an outcome study. Am J Phys Med Rehabil 2002;81(12):898-905, DOI:
https://doi.org/10.1097/00002060-200212000-00003.
3. Smith CC, Booker T, Schaufele MK, Weiss P. Interlaminar versus
transforaminal epidural steroid injections for the treatment of symptomatic
lumbar spinal stenosis. Pain Medicine (Malden, Mass). 2010;11(10):1511–5.
4. Fan ZQ, Fan YY. Discussion on the problems of using caudal epidural
steroid injections for treating lower back and leg pain associated with
lumbar disc herniation. J Cervicodynia Lumbodynia. 2009;30(5):441–3.
5. Masini M, Paiva WS, Araujo AS Jr. Anatomical description of the facet joint
innervation and its implication in the treatment of recurrent back pain. J
Neurosurg Sci. 2005;49(4):143–6.
6. Cavanaugh JM, Lu Y, Chen C, Kallakuri S. Pain generation in lumbar and
cervical facet joints. J Bone Joint Surg Am. 2006;88(Suppl 2):63–7.
7. Ma YQ, Yuan HS, Liu C. Current status and progess of lumbar selective
nerve root blocks. Chin J Pain Med. 2011;17(07):436–9.
8. Chagnas MO, Poiraudeau S, Lefevre-Colau MM, Rannou F, Nguyen C.
Diagnosis and management of lumbar spinal stenosis in primary care in
France: a survey of general practitioners. BMC Musculoskelet Disord. 2019;
20(1):431. https://doi.org/10.1186/s12891-019-2782-y.
9. Wildermuth S, Zanetti M, Duewell S, Schmid MR, Romanowski B, Benini A,
et al. Lumbar spine: quantitative and qualitative assessment of positional
(upright flexion and extension) MR imaging and myelography. Radiology.
1998;207(2):391–8. https://doi.org/10.1148/radiology.207.2.9577486.
10. Lee S, Lee JW, Yeom JS, Kim KJ, Kim HJ, Chung SK, et al. A practical MRI
grading system for lumbar foraminal stenosis. AJR Am J Roentgenol. 2010;
194(4):1095–8. https://doi.org/10.2214/AJR.09.2772.
11. Delport EG, Cucuzzella AR, Marley JK, Pruitt CM, Fisher JR. Treatment of
lumbar spinal stenosis with epidural steroid injections: a retrospective
outcome study. Arch Phys Med Rehabil. 2004;85(3):479–84. https://doi.org/1
0.1016/S0003-9993(03)00472-6.
12. Fukusaki M, Kobayashi I, Hara T, Sumikawa K. Symptoms of spinal stenosis
do not improve after epidural steroid injection. Clin J Pain. 1998;14(2):148–
51. https://doi.org/10.1097/00002508-199806000-00010.
13. Koc Z, Ozcakir S, Sivrioglu K, Gurbet A, Kucukoglu S. Effectiveness of physical
therapy and epidural steroid injections in lumbar spinal stenosis. Spine (Phila
Pa 1976). 2009;34(10):985–9. https://doi.org/10.1097/BRS.0b013e31819c0a6b.
14. Wang JW. Clinical analysis of conservative treatments and surgical
treatments for lumbar disc herniation. Contemp Med. 2017;23(2):79–80.
15. Wu LJ, He YH, Wang L. The efficacy of epidural nerves blocks in the
treatment of lumbar disc herniation: a randomized controlled study.
Contemp Med. 2016;22(29):3–4.
16. Run W, Yang L. Preliminary assessment and study of the efficacy of selective
nerve root block in the treatment of lumbar degenerative diseases. China
Foreign Med Treatment. 2016;35(6):30–2.
17. Zhang H, Yang YL, Li Y, et al. The effectiveness study of selective nerve
block surgery in lumbar foraminal stenosis therapy. J Cervicodynia
Lumbodynia. 2016;37(3):182–5.
18. Weiner BK, Fraser RD. Foraminal injection for lateral lumbar disc herniation. J
Bone Joint Surg Br. 1997;79(5):804–7. https://doi.org/10.1302/0301-620X.
79B5.0790804.
19. Narozny M, Zanetti M, Boos N. Therapeutic efficacy of selective nerve root
blocks in the treatment of lumbar radicular leg pain. Swiss Med Wkly. 2001;
131(5-6):75–80.
20. He J, L J, Feng Y, et al. The correlation between LANSS score and pain
intensity.Chinese Journal of Pain Medicine 2017;23(1): 39-43.
21. Manchikanti L, Cash KA, McManus CD, Pampati V, Abdi S. Preliminary results
of a randomized, equivalence trial of fluoroscopic caudal epidural injections
in managing chronic low back pain: part 4-spinal stenosis. Pain Physician.
2008;11(6):833–48.
22. Sadiq M, Hussain SA. Comments on the article “selective nerve root blocks
vs. caudal epidural injection for single level prolapsed lumbar intervertebral
disc - a prospective randomized study”. J Clin Orthopaedics Trauma. 2019;
10(Suppl 1):S264.
23. Nakahashi M, Uei H, Hoshino M, Omori K, Igarashi H, Tokuhashi Y.
Anatomical evaluation of the sacral hiatus using ultrasound imaging: factors
that inhibit needle insertion during caudal epidural block procedures. Pain
Practice. 2020;20(1):55–61. https://doi.org/10.1111/papr.12826.
24. Bagheri H, Govsa F. Anatomy of the sacral hiatus and its clinical relevance in
caudal epidural block. Surg Radiol Anat. 2017;39(9):943–51. https://doi.org/1
0.1007/s00276-017-1823-1.
25. Ko S, Chae S, Choi W, Kwon J. Prolonged pain reducing effect of sodium
hyaluronate-carboxymethyl cellulose solution in the selective nerve root
block (SNRB) of lumbar radiculopathy: a prospective, double-blind,
randomized controlled clinical trial. Spine J. 2019;19(4):578–86. https://doi.
org/10.1016/j.spinee.2018.10.011.
26. Liu PF, Zhang W, Wang HW, et al. Transforaminal selective nerve root injection
for lumbar disc herniation. Chin J Spine Spinal Cord. 2013;23(3):286–8.
27. Lee JW, Kim SH, Choi JY, Yeom JS, Kim KJ, Chung SK, et al. Transforaminal
epidural steroid injection for lumbosacral radiculopathy: preganglionic
versus conventional approach. Korean J Radiol. 2006;7(2):139–44. https://doi.
org/10.3348/kjr.2006.7.2.139.
28. Manchikanti L, Hirsch JA, Smith HS. Evidence-based medicine, systematic
reviews, and guidelines in interventional pain management: part 2.
Randomized controlled trials. Pain Physician. 2008;11(6):717–73.
29. Fairbank JCT, Pynsent PB. The Oswestry disability index. Spine. 2000;25(22):
2940–53. https://doi.org/10.1097/00007632-200011150-00017.
Publisher’sNote
Springer Nature remains neutral with regard to jurisdictional claims in
published maps and institutional affiliations.
Osman et al. Trials (2021) 22:524 Page 8 of 8
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
1.
2.
3.
4.
5.
6.
Terms and Conditions
Springer Nature journal content, brought to you courtesy of Springer Nature Customer Service Center GmbH (“Springer Nature”).
Springer Nature supports a reasonable amount of sharing of research papers by authors, subscribers and authorised users (“Users”), for small-
scale personal, non-commercial use provided that all copyright, trade and service marks and other proprietary notices are maintained. By
accessing, sharing, receiving or otherwise using the Springer Nature journal content you agree to these terms of use (“Terms”). For these
purposes, Springer Nature considers academic use (by researchers and students) to be non-commercial.
These Terms are supplementary and will apply in addition to any applicable website terms and conditions, a relevant site licence or a personal
subscription. These Terms will prevail over any conflict or ambiguity with regards to the relevant terms, a site licence or a personal subscription
(to the extent of the conflict or ambiguity only). For Creative Commons-licensed articles, the terms of the Creative Commons license used will
apply.
We collect and use personal data to provide access to the Springer Nature journal content. We may also use these personal data internally within
ResearchGate and Springer Nature and as agreed share it, in an anonymised way, for purposes of tracking, analysis and reporting. We will not
otherwise disclose your personal data outside the ResearchGate or the Springer Nature group of companies unless we have your permission as
detailed in the Privacy Policy.
While Users may use the Springer Nature journal content for small scale, personal non-commercial use, it is important to note that Users may
not:
use such content for the purpose of providing other users with access on a regular or large scale basis or as a means to circumvent access
control;
use such content where to do so would be considered a criminal or statutory offence in any jurisdiction, or gives rise to civil liability, or is
otherwise unlawful;
falsely or misleadingly imply or suggest endorsement, approval , sponsorship, or association unless explicitly agreed to by Springer Nature in
writing;
use bots or other automated methods to access the content or redirect messages
override any security feature or exclusionary protocol; or
share the content in order to create substitute for Springer Nature products or services or a systematic database of Springer Nature journal
content.
In line with the restriction against commercial use, Springer Nature does not permit the creation of a product or service that creates revenue,
royalties, rent or income from our content or its inclusion as part of a paid for service or for other commercial gain. Springer Nature journal
content cannot be used for inter-library loans and librarians may not upload Springer Nature journal content on a large scale into their, or any
other, institutional repository.
These terms of use are reviewed regularly and may be amended at any time. Springer Nature is not obligated to publish any information or
content on this website and may remove it or features or functionality at our sole discretion, at any time with or without notice. Springer Nature
may revoke this licence to you at any time and remove access to any copies of the Springer Nature journal content which have been saved.
To the fullest extent permitted by law, Springer Nature makes no warranties, representations or guarantees to Users, either express or implied
with respect to the Springer nature journal content and all parties disclaim and waive any implied warranties or warranties imposed by law,
including merchantability or fitness for any particular purpose.
Please note that these rights do not automatically extend to content, data or other material published by Springer Nature that may be licensed
from third parties.
If you would like to use or distribute our Springer Nature journal content to a wider audience or on a regular basis or in any other manner not
expressly permitted by these Terms, please contact Springer Nature at
onlineservice@springernature.com
