A Clinical Comparison in Cervical Epidural Pressure Changes Between Midline and Paramedian Approaches

Study Overview
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Brief Summary
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Ligamentum flavum in the cervical region is thin or not fused at the midline. The investigators inferred that the size and elasticity of the ligamentum flavum, in combination with mildline appraoch, the gaps could be responsible for a failure to recognize a LOR in some patients. If so, the investigators hypothesized that the paramedian approach would be advantageous for finding cervical epidural space more easily during cervical epidural steroid injections (CESIs).

Detailed Description
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Ligamentum flavum in the cervical region is thin or not fused at the midline. The distinct elastic resistance offered by the ligamentum flavum before entering the epidural space when using the loss of resistance (LOR) technique may be blunted or even absent. The investigators inferred that the size and elasticity of the ligamentum flavum, in combination with mildline appraoch, the gaps could be responsible for a failure to recognize a LOR in some patients. If so, the investigators hypothesized that the paramedian approach would be advantageous for finding cervical epidural space more easily during cervical epidural steroid injections (CESIs). Therefore, the investigators randomly divide our patients into 2 groups; the midline approach group and the paramedian group. Then, the investigators examine the patterns of the pressure changes at the moment of a puncture of the ligamentum flavum during CESIs.

Official Title
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Advantages of the Paramedian Approach for Cervical Epidural Steroid Injections: A Clinical Comparison in Cervical Epidural Pressure Changes Between Midline and Paramedian Approaches

Conditions
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Herniated Nucleus Pulposus, Whiplash Injury

Intervention / Treatment
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* Procedure: Cervical epidural steroid injection


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 20 to 80 yr Cervical radicular pain caused by herniated nucleus pulposus, spinal steonosis, or other conditions, including herpes zoster-associated pain and whiplash injury for more than 3 months Pain intensity > 4 of maximum 10 NRS Failure to improve with conservative treatment Cervical epidural location of needle confirmed by the fluoroscopic images Exclusion Criteria: Acute infection Patient refusal Previous cervical spine surgery Structural spinal deformities or A space-occupying epidural mass Rapidly worsening pain, numbness, weakness, hyperreflexia, changes in bladder function, and other neurological symptoms that should prompt a reevaluation and surgical evaluation Pregnancy Allergy to contrast media or drugs to be used in the procedure

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: midline approach<br>cervical epidural steroid injection with 18G Touhy epidural needle by midline approach | Procedure: Cervical epidural steroid injection<br>* cervical epidural steroid injection with a solution (5 ml) containing 10 mg triamcinolone acetonide suspension, 1.5 ml of 0.75% levobupivacaine hydrochloride, and 3.5 ml of normal saline (0.9% NaCl)<br>|
| Active Comparator: paramedian approach<br>cervical epidural steroid injection with 18G Touhy epidural needle by paramedian approach | Procedure: Cervical epidural steroid injection<br>* cervical epidural steroid injection with a solution (5 ml) containing 10 mg triamcinolone acetonide suspension, 1.5 ml of 0.75% levobupivacaine hydrochloride, and 3.5 ml of normal saline (0.9% NaCl)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| precipitous decrease | Existence of the precipitous decrease in pressure at the moment of entering the cervical epidural space (exist or not) | It will be measured at the moment of puncture of ligamentum flavum during interventional procedure, then participants will be followed for the duration of hospital stay, an expected average of 1 hour. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| popping sensation | Existence of the tactile sensation of give by pain experts (exist or not) | It will be measured at the moment of puncture of ligamentum flavum during interventional procedure, then participants will be followed for the duration of hospital stay, an expected average of 1 hour. | 
| spreading levels of dye according to dye volume | Dye Volume / Dye Spreading Level after injection of 0.5 cc contrast dye, then check the spreading level such as the number of vertebral body and unilateral or bilateral spreading | It will be measured during interventional procedure, then participants will be followed for the duration of hospital stay, an expected average of 1 hour. | 
| cervical epidural pressure | The bevel of the needle is considered to have entered the epidural space when a typical waveform is observed, which consists of small cardiac oscillations superimposed on greater respiratory oscillations. The needle is then held immobile in the epidural space for 120 s to allow the epidural pressure to stabilize, and CEP is measured. | It will be measured during interventional procedure, then participants will be followed for the duration of hospital stay, an expected average of 1 hour. |