What are the considerations and potential risks for a patient with back pain undergoing a transforminal epidural steroid injection (ESI), specifically a corticosteroid such as triamcinolone or betamethasone?

Transforaminal Epidural Steroid Injection (TFESI): Clinical Considerations and Risk Profile

Direct Recommendation

Transforaminal epidural steroid injections should only be performed for radicular pain (pain radiating below the knee) with MRI-confirmed nerve root compression after at least 4-6 weeks of failed conservative therapy, and must be done under fluoroscopic guidance with full informed consent about catastrophic risks including paralysis, stroke, and death. 1, 2, 3

Critical FDA Warning

The FDA explicitly states that the safety and effectiveness of epidural administration of corticosteroids have not been established, and corticosteroids are not approved for epidural use. 3 Serious neurologic events resulting in death have been reported with epidural injection of corticosteroids, including:

• Spinal cord infarction
• Paraplegia and quadriplegia
• Cortical blindness
• Stroke 3

These catastrophic complications occur with and without fluoroscopy. 3

Absolute Requirements Before Proceeding

Patient Selection Criteria

You must verify ALL of the following before considering TFESI:

• Radicular pain pattern: Pain and/or numbness radiating below the knee (not just back pain or buttock pain) 2, 4
• MRI confirmation: Nerve root compression documented on imaging within 24 months 2, 4
• Failed conservative therapy: Minimum 4-6 weeks of physical therapy, NSAIDs, and activity modification 2, 4
• Anatomic-clinical correlation: MRI findings must match the dermatomal pain distribution 2

Absolute Contraindications

Do NOT perform TFESI for:

• Chronic axial spine pain without radiculopathy - The 2025 BMJ guideline provides a strong recommendation stating "all or nearly all well-informed people would likely not want such interventions" 1, 2
• Spinal stenosis without significant radicular symptoms 1, 2
• Non-radicular low back pain 1, 4
• Facet-mediated pain 1

Procedural Safety Requirements

Mandatory Fluoroscopic Guidance

Fluoroscopy is absolutely required for transforaminal injections to ensure proper needle placement and minimize (but not eliminate) catastrophic complications. 2, 4, 5 The transforaminal approach carries higher risk than interlaminar approaches due to proximity to vascular structures. 2

Corticosteroid Selection

Particulate steroids (triamcinolone, betamethasone acetate) carry higher risk of catastrophic neurological complications than non-particulate steroids (dexamethasone) when administered transforaminally. 6 Seven of 10 comparative studies found non-particulate steroids had comparable efficacy to particulate steroids. 6

Common pitfall: Many commercial formulations contain neurotoxic preservatives - verify preservative-free preparations. 6

Required Informed Consent Discussion

You must explicitly discuss these specific complications with the patient:

• Dural puncture
• Insertion-site infections
• Cauda equina syndrome
• Sensorimotor deficits
• Discitis
• Epidural granuloma
• Retinal complications
• Paralysis and death 2, 4, 3

Evidence for Efficacy

When TFESI May Be Appropriate

For disc herniation with radiculopathy: Evidence is Level II-1 for short-term relief (up to 6 months) and Level II-2 for long-term relief. 7, 8 The 2021 ASIPP guidelines provide moderate to strong recommendations for fluoroscopically guided transforaminal injections in disc herniation. 1

For spinal stenosis with radiculopathy: Evidence is fair for local anesthetic and steroids. 8

When TFESI Should NOT Be Used

The evidence is poor, inadequate, or limited for:

• Axial low back pain 8
• Post-lumbar surgery syndrome 8
• Chronic low back pain without radiculopathy 1

Repeat Injection Criteria

Do not repeat TFESI unless the initial injection provided at least 50% pain relief for at least 2 weeks (preferably 2 months). 2, 4 Exposing patients to catastrophic risks without demonstrated prior benefit is not justified. 2

Common pitfall: Do not repeat injections based solely on patient request without objective evidence of prior benefit. 2

Multimodal Treatment Context

TFESI must be part of a comprehensive pain management program including:

• Ongoing physical therapy
• Patient education
• Psychosocial support
• Oral medications where appropriate 2, 4

TFESI should never be performed in isolation or as maintenance therapy. 2, 9

Alternative Diagnoses to Consider

Before proceeding with TFESI, evaluate for:

• Sacroiliac joint dysfunction: If 3 of 6 provocative tests are positive, consider diagnostic SI joint injection first 2
• Facet-mediated pain: Consider diagnostic medial branch blocks 1
• Hip pathology: Especially in older patients with groin/lateral thigh pain 2

Risk-Benefit Analysis

The 2025 BMJ guideline notes that patients would be disinclined to receive treatment with an interventional procedure for which there is very low certainty of evidence for benefit or low certainty of evidence for no benefit, combined with moderate to high certainty evidence of risk of harm. 1

Catastrophic complications are rare enough that true incidence cannot be calculated from existing cohorts, but even a single case of paralysis or death is unacceptable without clear indication and informed consent. 10

Documentation Requirements

Your medical record must clearly document:

• Radicular pain pattern extending below the knee 2
• MRI findings with anatomic-clinical correlation 2
• Minimum 4-6 weeks of failed conservative therapy 2
• Comprehensive informed consent discussion including catastrophic risks 2, 3
• Fluoroscopic guidance utilized 2, 4
• Multimodal treatment plan 2