The Incidence of the Intravascular Injection During S1 Transforaminal Epidural Steroid Injection in Two Approaches: Medial vs Lateral in Anteroposterior View

Study Overview
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Brief Summary
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Lumbosacral transforaminal epidural steroid injection (TFESI) is helpful for the treatment of lumbosacral radicular pain, but in case of intravascular injection, infrequently serious complication can be developed. Against this backdrop, if there is any difference of frequency of intravascular injection incidence during S1 (sacrum 1) TFESI between method using medial approach and method using lateral approach in anteroposterior view, the result can be crucial factor in selecting the approach. In addition, appropriate volume of injection will be checked in each approach.

Conditions
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Lumbosacral Radicular Pain

Intervention / Treatment
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* Drug: S1 transforaminal epidural steroid(dexamethasone) injection


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 1. Adult patients (20-80 years of age) who were scheduled to receive S1 transforaminal epidural steroid injection for lumbosacral radicular pain at pain management clinic Exclusion Criteria: pregnancy coagulopathy systemic infection any active infection at the injection site history of allergy to contrast media, local anesthetics, corticosteroid patients unable to communicate or patients with cognitive dysfunction

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: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: medial approach group<br> | Drug: S1 transforaminal epidural steroid(dexamethasone) injection<br>* medial approach group (n=85): check intravascular injection while performing S1 transforaminal epidural steroid(dexamethasone) injection in medial side of S1 foramen under fluoroscopy lateral approach group (n=85): same as medial approach group except using lateral side of S1 foramen<br>|
| Active Comparator: lateral approach group<br> | Drug: S1 transforaminal epidural steroid(dexamethasone) injection<br>* medial approach group (n=85): check intravascular injection while performing S1 transforaminal epidural steroid(dexamethasone) injection in medial side of S1 foramen under fluoroscopy lateral approach group (n=85): same as medial approach group except using lateral side of S1 foramen<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the incidence of intravascular injection in the medial approach group in S1 foramen |  | 5 seconds after injection of contrast media via block needle. | 
| the incidence of intravascular injection in the lateral approach group in S1 foramen |  | 5 seconds after injection of contrast media via block needle. |