Lumbar Disc Herniation, Lumbosacral Radiculopathy
Conditions
Keywords
Epidural Steroid Injection, Parasagittal Interlaminar Injection, Transforaminal Epidural Steroid Injection, Radicular Pain, Fluoroscopy, Oswestry Disability Index, Numerical Rating Scale, Contrast Spread
Brief summary
This study will compare three fluoroscopy-guided epidural steroid injection approaches for adults with unilateral lumbosacral radicular pain caused by lumbar disc herniation. The study will evaluate whether the pattern of contrast spread in the epidural space predicts meaningful pain relief. Ninety-nine participants will be randomly assigned in equal numbers to receive one of three treatments: high-volume parasagittal interlaminar injection, low-volume parasagittal interlaminar injection, or transforaminal epidural steroid injection. Participants will not be told which injection approach they receive. Pain and disability will be assessed before treatment and at 2 weeks, 1 month, 3 months, and 6 months after injection. The main outcome is the proportion of participants with clinically meaningful improvement in pain at 3 months.
Detailed description
Lumbar disc herniation may cause lumbosacral radicular pain through nerve-root compression and inflammation. Fluoroscopy-guided epidural steroid injections are commonly used when symptoms persist despite conservative treatment. Parasagittal interlaminar (PIL) and transforaminal epidural steroid injection (TFESI) approaches may produce different patterns of contrast distribution within the epidural space. It remains unclear whether contrast spread pattern independently predicts clinical response, apart from injection approach and injectate volume. This prospective, three-arm randomized clinical trial will enroll adults with unilateral lumbosacral radicular pain and magnetic resonance imaging-confirmed lumbar disc herniation. Participants will be allocated in a 1:1:1 ratio to high-volume PIL injection (10 mL), low-volume PIL injection (7 mL), or TFESI (3 mL). Before administration of the therapeutic injectate, 2 mL of non-ionic iodinated contrast medium will be injected under real-time fluoroscopy to confirm epidural placement, exclude intravascular or intrathecal injection, and document contrast distribution. Blinded assessors will classify contrast spread according to ventral epidural spread, laterality, foraminal or nerve-root spread, epidural distribution pattern, and cephalocaudal extent. Dynamic fluoroscopic assessment will measure time to first ventral opacification. Participants, radiographic assessors, and outcome assessors will be blinded to treatment allocation where feasible; the procedural physician cannot be blinded because of the procedural differences. The study will assess whether contrast spread variables independently predict responder status at 3 months, defined as a reduction of at least 2 points or 30% from baseline in Numerical Rating Scale pain score. Additional outcomes include changes in pain intensity and Oswestry Disability Index scores, procedural efficiency, duration of pain relief, and responder status during follow-up through 6 months.
Interventions
PROCEDUREHigh-Volume Parasagittal Interlaminar Epidural Steroid Injection
Fluoroscopy-guided parasagittal interlaminar epidural steroid injection on the symptomatic side. After a standardized 2 mL non-ionic iodinated contrast injection, 10 mL therapeutic injectate is administered: betamethasone 24 mg and bupivacaine 0.5% 20 mg.
PROCEDURELow-Volume Parasagittal Interlaminar Epidural Steroid Injection
Fluoroscopy-guided parasagittal interlaminar epidural steroid injection on the symptomatic side. After a standardized 2 mL non-ionic iodinated contrast injection, 7 mL therapeutic injectate is administered: betamethasone 16.8 mg and bupivacaine 0.5% 14 mg.
Fluoroscopy-guided transforaminal epidural steroid injection at the symptomatic level and side. After a standardized 2 mL non-ionic iodinated contrast injection, 3 mL therapeutic injectate is administered: betamethasone 7.2 mg and bupivacaine 0.5% 6 mg.
Administered in volume-proportional doses: 24 mg in High-Volume PIL, 16.8 mg in Low-Volume PIL, and 7.2 mg in TFESI.
DRUGBupivacaine
Bupivacaine 0.5% is administered in volume-proportional doses: 20 mg in High-Volume PIL, 14 mg in Low-Volume PIL, and 6 mg in TFESI.
Sponsors
Benha University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Outcomes Assessor)
Masking description
Participants will be blinded to the assigned injection approach and injectate volume. Outcome assessors collecting pain and disability scores and radiographic assessors evaluating contrast-spread images will be blinded to treatment allocation. The procedural physician cannot be blinded because of inherent differences between injection techniques. Statistical analysis will be conducted with the analyst blinded to arm assignment where feasible.
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
No
Inclusion criteria
* Age 18 to 65 years. * Unilateral lumbosacral radicular pain consistent with a dermatomal distribution. * Magnetic resonance imaging-confirmed lumbar disc herniation (bulge, protrusion, or extrusion) at the corresponding clinical level. * Persistent symptoms despite at least 6 weeks of conservative management, including analgesics and physiotherapy. * Baseline Numerical Rating Scale pain score of 4 or greater. * American Society of Anesthesiologists physical status I to III. * Ability to understand and complete outcome assessments. * Written informed consent provided.
Exclusion criteria
* Previous lumbar spine surgery or failed back surgery syndrome. * Red-flag signs, including foot drop, urinary incontinence, or cauda equina syndrome. * Bilateral radicular symptoms or central canal stenosis requiring surgical intervention. * Coagulopathy or ongoing anticoagulant therapy. * Local or systemic infection or hepatic dysfunction. * Known allergy to contrast medium, local anesthetics, or corticosteroids. * Pregnancy. * Severe renal impairment contraindicating contrast use. * Chronic opioid use, defined as daily opioid use for more than 3 months before enrollment. * Uncontrolled systemic disease, including unstable diabetes or severe cardiopulmonary disease. * Inability to comply with follow-up.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Proportion of Participants With Clinically Meaningful Pain Response | 3 months after injection | Responder status is defined as a reduction from baseline of at least 2 points or at least 30% in Numerical Rating Scale (NRS) pain score. The association between contrast-spread variables and responder status will be assessed. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in Numerical Rating Scale Pain Score | Baseline, 2 weeks, 1 month, 3 months, and 6 months after injection. | Mean change from baseline in pain intensity measured using the Numerical Rating Scale (NRS), an 11-point scale ranging from 0 to 10, where 0 indicates no pain and 10 indicates the worst imaginable pain. Higher scores indicate greater pain severity. Change in NRS pain score will be calculated as the score at each follow-up time point minus the baseline score. Units of measure: i'd use points on a scale |
| Change in Oswestry Disability Index Score | Baseline; 2 weeks, 1 month, 3 months, and 6 months after injection | Change from baseline in Oswestry Disability Index score; scores are expressed from 0% to 100%, with higher scores indicating greater disability. |
| Total fluoroscopy time | During the index injection procedure | Total duration of fluoroscopy exposure during the index injection procedure. Measured in seconds. |
| number of fluoroscopic images | During the index injection procedure | Total number of fluoroscopic images acquired during the index injection procedure. Measured by number of images. |
| procedure duration | During the index injection procedure | Total duration of the index injection procedure, measured from the start of the procedure until completion of the injection. Measured in minutes. |
| Duration of Pain Relief | From injection through 6 months after injection | Time from index injection to loss of benefit, defined as return to less than 30% NRS reduction from baseline or participant request for repeat intervention or surgical referral. |
Countries
Egypt
Contacts
CONTACTanas fetian, M.B.B.Ch., M.Sc.
Outcome results
None listed