The Influence of Needle-insertion Depth on Successful Epidurogram and Clinical Outcome in Caudal Epidural Injections

Study Overview
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Brief Summary
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Caudal epidural injections have been commonly performed in patients with low back pain and radiculopathy. Conventional caudal epidural injections, which the needle is advanced into the sacral canal, present a potential risk of penetration of the epidural venous plexus or dura. The investigators hypothesized that a new caudal injection technique, which the needle only penetrates the sacrococcygeal ligament without being inserted into the sacral canal, might represent a safe alternative, with a lower incidence of intravascular injections and patient's discomfort during the procedure than the conventional technique. The study is designed to investigate the influence of the depth of the inserted needle on successful epidurogram and clinical outcome in caudal epidural injections under the ultrasound and digital subtraction angiography.

Official Title
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The Influence of Needle-insertion Depth on Successful Epidurogram and Clinical Outcome in Caudal Epidural Injections: A Randomized Clinical Trial

Conditions
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Lumbosacral Radicular Pain

Intervention / Treatment
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* Procedure: new caudal injection technique


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult patients (20-80 years of age) who were scheduled to receive caudal epidural injection for lumbosacral radicular pain at our 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: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Group A<br>Conventional method group (n=85): caudal injection after advancement of the needle into the sacral canal. Ultrasound is used to achieve accurate needle placement and we will check intravascular injection using digital subtraction angiography. | |
| Experimental: Group B<br>New method group (n=85): same as conventional method group except caudal injection right after penetrating the sacrococcygeal ligament. | Procedure: new caudal injection technique<br>* new caudal injection technique is applied to the Group B, which is that the needle only penetrates the sacrococcygeal ligament without being inserted into the sacral canal<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the incidence of intravascular injection | the incidence of intravascular injection in the conventional method group and the new method group during the caudal epidural injections. | 5 seconds after injection of contrast media via block needle. |