Do Cervical Interlaminar Epidural Steroid Injections With Low-dose Lidocaine Cause Transient Objective Upper Extremity Weakness? A Prospective Randomized
Phase: PHASE4
Conditions: Cervical Radiculopathy
Sponsor: University of Utah

PI:  Zachary McCormick, MD 
Title: Do Cervical Interlaminar Epidural Steroid Injections with Low-dose Lidocaine Cause Transient Objective Upper Extremity Weakness? A 
Prospective Randomized Controlled Trial  
Version:  3.0, 17JUL2017 
 
Page 1 of 9 
 
Title: Do Cervical Interlaminar Epidural Steroid Injections with Low-dose Lidocaine 
Cause Transient Objective Upper Extremity Weakness? A Prospective Randomized 
Controlled Trial  
 
Co-Primary Investigator: Zachary McCormick, MD, Richard Kendall, DO 
 
 
Research Question(s):  
Primary: Does lidocaine versus saline as a steroid diluent affect objective upper extremity 
strength following cervical epidural steroid injection in patients being treated for cervical 
radicular pain?  
 
Secondary: Does lidocaine versus saline as a steroid diluent affect short-term pain, function, 
medication use, and global impression of change outcomes of cervical epidural injection for the 
treatment of radicular pain? 
 
Null Hypothesis: 
1. Cervical epidural steroid injections that include local anesthetic as a diluent have no 
effect on objective upper extremity strength following the injection. 
2. Cervical epidural steroid injections for radicular pain that include lidocaine compared to 
saline as a diluent do not improve short-term pain, function, medication use, and global 
impression of change outcomes. 
 
Introduction 
Cervical radicular pain is a common problem that is often treated by epidural steroid injection 
(1). While clinical practice guidelines do not specifically recommend or discourage the use of 
local anesthetic in the epidural injectate (2), the majority of the published literature on clinical 
outcomes of cervical epidural steroid injection includes the use of lidocaine in the epidural 
injectate (3-11). Consequently, many practitioners elect to use local anesthetic in the epidural 
injectate in order to obtain additional diagnostic information when the precise source of pain is 
not clear from clinical presentation and imaging. Local anesthetic may also be included in order 
to provide immediate pain relief in cases of painful acute radicular symptoms.  
 
Local anesthetic injection into the epidural space has the potential to cause transient weakness of 
the upper extremities. High dose local anesthetic in the cervical epidural space (12) and 
inappropriately placed low-dose local anesthetic in the subdural space or subarachnoid space (13, 
14) are known to cause motor weakness. Appropriately placed, low-dose local anesthetic injected 
into the epidural space via a transforaminal approach, in close proximity to the exiting spinal 
nerve root, causes motor block in a small proportion of patients (15). However, the effect of low-
dose injection of local anesthetic in the cervical interlaminar epidural space on objective upper 
extremity strength has not been characterized in the published literature. This proposition affects 
post-procedure instructions, as even mild weakness may pose a hazard during performance 
manual activities that require the upper extremity/extremities such as using a handrail or cane 
handle for support.   
 

PI:  Zachary McCormick, MD 
Title: Do Cervical Interlaminar Epidural Steroid Injections with Low-dose Lidocaine Cause Transient Objective Upper Extremity Weakness? A 
Prospective Randomized Controlled Trial  
Version:  3.0, 17JUL2017 
 
Page 2 of 9 
 
Dynamometry is an established and validated method for assessing muscle strength and motor 
neuron function with high reliability, and has been used to objectively assess changes in upper 
extremity strength. 
 
This study aims to determine whether a standard dose of 2 mL 1% lidocaine included as a steroid 
diluent in a C7-T1 cervical interlaminar epidural steroid injection (CESI) causes an objective 
change in strength as measured by dynamometry. We hypothesized that cervical epidural 
lidocaine will cause an objective decrease in strength in functional movements of the upper 
extremity.  
 
Significance: 
Cervical radicular pain is relatively common, often treated with epidural steroid injection (ESI), 
when conservative treatments like oral analgesics, physical therapy, and activity modification 
have failed. There are no universal clinical practice guidelines for the use of diluents when CESI 
are performed.  
 
Interlaminar CESI may be performed with or without the use of local anesthetics, due to training 
bias or theoretical concerns of weakness. CESI without the benefit of local anesthetic as a steroid 
diluent increases the latency of pain relief and may decrease diagnostic information immediately 
after a CESI with regard to pain generators responsible for symptoms, and may potentially 
decrease patient satisfaction. 
 
By evaluating the effects of local anesthetic as a diluent during interlaminar cervical ESI, we will 
enhance the safety of this treatment with regard to expectations of objective motor weakness as 
well as post procedure pain control in the recovery phase after the injection procedure.  
 
Additionally, investigation of short-term pain, function, medication use, and global impression of 
change following use of local anesthetic versus saline as a diluent during interlaminar cervical 
ESI will provide evidence to inform the optimization of clinical outcomes related to steroid 
diluent choice. 
 
Subjects 
A total of 104 subjects, aged 18-80 on the day of enrollment, will be recruited for participation in 
this study.  Patients will be randomized to one of two groups based on a random computer-
generated schedule.  
 
Those assigned to Group #1 will undergo a interlaminar cervical ESI with local anesthetic as a 
steroid diluent. Those in Group #2 will receive a interlaminar cervical ESI with saline as a 
steroid diluent. 
 
 
De-identification 
All subjects will be assigned a unique alphanumeric identifier.  No personally identifiable 
information will be used in the final database, in order to ensure compliance with HIPPA and 
hospital policy.  All data will be stored on a highly secure, password protected computer. 

PI:  Zachary McCormick, MD 
Title: Do Cervical Interlaminar Epidural Steroid Injections with Low-dose Lidocaine Cause Transient Objective Upper Extremity Weakness? A 
Prospective Randomized Controlled Trial  
Version:  3.0, 17JUL2017 
 
Page 3 of 9 
 
 
Participant Recruitment 
Our intended subject demographic includes an active population between the ages of 18 and 80 
years on the day of enrollment.  We intend to recruit participants primarily through word-of-mouth 
and from a database or participant pool for which participants have given prior permission to be 
contacted for research studies. Additionally, recruiting will take place through the distribution of 
flyers to the Health Sciences Education Building, University of Utah Student Life Center, the 
University of Utah South Jordan Health Center, the University of Utah Orthopaedic Center, and 
the University of Utah hospital.  Upon first contact with the potential participant, the study 
coordinator or research associate will provide a basic description of the study and review inclusion 
and exclusion criteria, general health status, and past and current athletic participation.  Interested 
volunteers who qualify will be asked to report to the University of Utah Orthopaedic Center.  Prior 
to screening procedures and after being informed of any potential risks involved in the study, 
volunteers will be asked to provide written, informed consent for study participation. 
 
Inclusion criteria: 
1) Age 18-80. 
2) Clinical diagnosis of cervical radicular pain. 
3) Magnetic resonance imaging pathology consistent with clinical symptoms/signs. 
4) Numerical Rating Scale (NRS) pain score of 4 or higher. 
5) Pain duration of more than 6 weeks despite trial of conservative therapy (medications, 
physical therapy, or chiropractic care).  
6) Patients who will undergo CESI for treatment of cervical radiculitis.  
 
Exclusion criteria: 
1) Refusal to participate, provide consent, or provide communication and follow-up 
information for duration of the study. 
2) Inability to perform handgrip or arm strength testing. 
3) Contraindications to Cervical ESI (active infection, bleeding disorders, current 
anticoagulant or antiplatelet medication use, allergy to medications used for CIESI, and 
pregnancy). 
4) Cervical spinal cord lesions; cerebrovascular, demyelinating, or other neuro-muscular 
muscular disease.  
5) Patient request for or requirement of conscious sedation for the injection procedure. 
 
Study design: 
 
Prospective, randomized, controlled, double blinded trial in patients undergoing CESI for 
symptoms of cervical radicular pain. 
 
Patients will be randomized to group #1 or #2 based on a random computer-generated schedule. 
 
Group #1:  Interlaminar cervical ESI at the C7-T1 level with triamcinolone 80 mg (40 mg/mL) + 
2 mL 1% lidocaine (total volume 4 mL). 
 

PI:  Zachary McCormick, MD 
Title: Do Cervical Interlaminar Epidural Steroid Injections with Low-dose Lidocaine Cause Transient Objective Upper Extremity Weakness? A 
Prospective Randomized Controlled Trial  
Version:  3.0, 17JUL2017 
 
Page 4 of 9 
 
Group #2: Interlaminar cervical ESI at the C7-T1 level with triamcinolone 80 mg (40 mg/mL) + 
2 mL preservative saline (total volume 4 mL).  
 
Adults who are eligible and scheduled to have an epidural steroid injection with triamcinolone 
for treatment of cervical radicular pain at the University of Utah Orthopaedic Center or 
University of Utah South Jordan Health Center will be approached by authorized research 
personnel.  All eligible patients will be offered to participate in the study and all patients will 
sign a written informed consent form before proceeding and will also be consented for the 
procedure. Participating in the study is voluntary. The patients may choose not to enroll in the 
research. Patients will be presented with the same options of treatment whether they enroll or 
decide not to. 
 
Power Analysis 
Statistical Plan & Sample Size Calculation:  
Size of study groups:  
Group 1: n = 52 
Group 2: n = 52 
 
A power analysis was performed based upon previous observations of UE strength (28) using 
Fisher’s Exact Test. Sample sizes of 52 in each of the two treatment groups will achieve > 80% 
power to detect a group different in proportions, assuming 20% of patients in the Lidocaine 
group will demonstrate a motor deficit after the CESI and those in the Saline group will 
demonstrate no difference in motor strength after the CESI, assuming a 2% measurement error 
with the strength testing method described.  The alpha level of this test statistic is set at 0.05, but 
the significance level actually achieved by this study design is 0.0004.  
 
Procedure 
All patients evaluated in the University of Utah Orthopaedic Center who will have a CESI with 
triamcinolone will be considered for participation in the study. Subjects will be consented for 
participation in the study and informed consent will be obtained. Each subject will be 
randomized into a group assignment in a 1:1 manner, #1 or #2, as outlined in the Methods 
section above. All documentation will be stored using a unique coded identifier to ensure 
compliance with HIPPA. 
 
A Report Form will be used to record all pre- and post-procedure data (See Appendix)  
 
In every participant in Control Cohort, Group 1 and Group 2, a pre-procedure NRS pain score, 
pain medication use, and presence of subjective or objective symptoms of UE weakness will be 
recorded. Bilateral handgrip, wrist extension, elbow flexion, and elbow extension strength 
(myotomes C5-T1) will be measured by a trained research assistant prior to the injection 
procedure using a handheld JAMAR® PLUS+ digital dynamometer (Sammons Preston, 
Bollingbrook, IL) for hand grip strength and a Lafayette Manual Muscle Testing System model 
01163 (Lafayette Instrument Company, Lafayette, IN) for arm strength assessment.  Three 
baseline strength measurements will be recorded for each strength test (20,21). Validation studies 
using similar protocols for upper extremity functional strength measurement show a high degree 

PI:  Zachary McCormick, MD 
Title: Do Cervical Interlaminar Epidural Steroid Injections with Low-dose Lidocaine Cause Transient Objective Upper Extremity Weakness? A 
Prospective Randomized Controlled Trial  
Version:  3.0, 17JUL2017 
 
Page 5 of 9 
 
of test-retest reliability with a narrow range of variability [22–26]. Additionally, light touch and 
pinprick sensory testing in the C5-T1 dermatomes will performed with a tapered whisp of cotton 
and a disposable safety pin, respectively, in accordance with the methods described when 
performing an American Spinal Injury Association (ASIA) examination in accordance with the 
international standards for neurological classification of spinal cord injury (27). 
 
Measurements will be taken prior to and 30 minutes following the injection procedure. 
Participants in Group #1 and Group #2 will also be queried with the Upper Extremity Functional 
Index (UEFI) before the injection procedure and again 1 day after the procedure (administered 
via telephone).  
For Group 1 and Group 2, patients will be randomized to treatment group based on a random 
computer-generated schedule.  Participants will be blinded to the group to which they are 
randomized.  All standard procedures for CESIs will be followed as is standard practice 
including time out, skin prep, hemodynamic monitoring, image guidance, etc.  
Per randomization, triamcinolone acetonide 80 mg (Kenalog) (E. R. Squibb & Sons Limited, 
Uxbridge UK) will be combined with 2mL Lidocaine 1% or 2 mL preservative free saline and 
will be injected during the CESI procedure. In all cases, the total injectate volume will be 4 mL.  
All injections will be image guided with fluoroscopy, as is the current standard practice.  
Fluoroscopy time will be recorded.  
The participant will be discharged from the clinic with written discharge instructions (current 
standard practice). 
 
Participants will be telephoned and emailed by clinic personnel 1 day after the CESI to assess for 
subjective weakness in the hands or arms as well as any other adverse reactions.  As above, the 
UEFI will be administered at this time. 
 
Participants will only be recruited for this study for a single CESI.  Those who require repeat 
injections will not be recruited a second or third time.  
 
Data Collection: 
 
1   Data evaluation (See Case report form)  
 
 
2   Interpretation of Anticipated Results: 
 
Statistical analysis 
Differences in strength as measured by dynamometry pre-and post-injection will be assessed  
by Fishers exact test.  
Means and standard deviations of subject demographic data, as well as pain scores and UEFI 
scores will be calculated. 
 
Data Storage  

PI:  Zachary McCormick, MD 
Title: Do Cervical Interlaminar Epidural Steroid Injections with Low-dose Lidocaine Cause Transient Objective Upper Extremity Weakness? A 
Prospective Randomized Controlled Trial  
Version:  3.0, 17JUL2017 
 
Page 6 of 9 
 
Hard copy data will be collected and stored in a password-protected computer located in the 
Division of PM&R. Subjects will each be assigned an ID number that will be used as the sole 
identifier on any documents. Subject data will be compiled onto a single password protected file, 
where they will only be identified by their ID number. An enrollment log will be the only file 
where subject names are correlated with ID numbers. This will be kept in a separate, secure, 
password-protected file in the Division of PM&R.  
 
Data Analysis Plan 
The primary outcome will be the proportion of participants with 50% or greater reduction in 
neck and arm pain on the NRS pain score at the 1-month follow-up assessment. Secondary 
outcomes included reduction in median NRS pain score (both neck pain and arm pain), NDI-5, 
MQS III, opioid consumption in daily morphine equivalents, PGIC score, and satisfaction score. 
Secondary outcomes will also be defined based on categorical “responder analysis” definitions of 
important clinical change given the National Institutes of Health recommendation for responder 
analysis in the assessment of therapeutic spine pain interventions.31 The responder analysis will 
include the proportion of patients with 30% or greater improvement on the NDI-5,32,33 a PGIC 
score less than 3 (indicating “improved” or “very much improved”), a 6.8 or greater point 
reduction on the MQS III score (equivalent to approximately 10 daily morphine equivalents),34 
and the proportion of participants who undergo surgical spine surgery. 
 
Primary outcome: 
 
• Change in strength for each individual in each treatment group before and 30 minutes 
after CESI  
• Categorical analysis based on a minimally clinically important change of 19.5% for upper 
extremity strength assessment (29). 
 
Secondary outcomes: 
 
• Change in mean arterial pressure prior to, 30 minutes after CESI, via automated blood 
pressure cuff measure. 
• Change in HR prior to, 30 minutes after CESI 
• Change in NRS pain score from pre-injection to post injection (immediate) and 1-day. 
• Change in UEFI score from pre-injection to post injection (immediate) and 1-day. 
• Change in pain medication use from pre-injection to post injection (immediate) and 1-
day. 
• Procedure complications or adverse reactions to medications used 
 
 
Risks/Benefits: 
Risks of study participation are the same as those for any standard fluoroscopically guided 
cervical ESI performed for management of cervical radiculitis when more conservative methods 
have been exhausted or failed.  These risks include: local infection, epidural hematoma or 
abscess, dural puncture and potential post-dural puncture headache, paresthesia during needle 
placement, pain at the injection side, failure of technique to decrease pain levels, allergy to latex, 

PI:  Zachary McCormick, MD 
Title: Do Cervical Interlaminar Epidural Steroid Injections with Low-dose Lidocaine Cause Transient Objective Upper Extremity Weakness? A 
Prospective Randomized Controlled Trial  
Version:  3.0, 17JUL2017 
 
Page 7 of 9 
 
iodine/chlorhexidine, adhesives or any medications used during the procedure. Utilizing 
fluoroscopy, the risk of nerve damage, spinal cord injury or intravascular injection is less than 
1:500,000. The length of stay and length of recovery is no longer than that of a standard ESI 
performed in the PM&R Spine Clinic at present.  
 
There are no risks associated with the pre- and post-injection grip and arm strength testing with 
dynamometry.  In this study, the length of stay and length of recovery is no longer than that of a 
standard CESI performed in the Orthopaedic Center at present. 
 
There are no direct benefits to the individual by participating in this study. The patients will be 
presented with the same treatment options whether they enroll in the study or decide not to 
participate.  The information gained from this study may provide the investigators a better 
understanding of a patient’s pain and strength response following a cervical epidural steroid 
injection.     
 
Study Termination Criteria 
- 
Adverse events considered/identified by the medical staff during the procedure process 
- 
The subject requests to be withdrawn from the study during the procedure. 
 
 
Safety Monitoring Plan 
Safety will be monitored by all members of the study team: 
 
Zachary McCormick, MD 
Richard Kendall, MD 
 
The Principal Investigator is an MD at the University of Utah Orthopaedic Center and University 
of Utah South Jordan Health Center.  Members of the data and safety monitoring committee will 
be in close contact with all the subjects throughout the study, both in-person and via telephone. 
The members of the data and safety monitoring committee will review potential side effects and 
adverse reactions with each subject at the time of delivery of the study drug and at the time of each 
sample collection. All the committee members are located at the University of Utah Orthopaedic 
Center; all members have research experience. 
 
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PI:  Zachary McCormick, MD 
Title: Do Cervical Interlaminar Epidural Steroid Injections with Low-dose Lidocaine Cause Transient Objective Upper Extremity Weakness? A 
Prospective Randomized Controlled Trial  
Version:  3.0, 17JUL2017 
 
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PI:  Zachary McCormick, MD 
Title: Do Cervical Interlaminar Epidural Steroid Injections with Low-dose Lidocaine Cause Transient Objective Upper Extremity Weakness? A 
Prospective Randomized Controlled Trial  
Version:  3.0, 17JUL2017 
 
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