What is the role of epidural steroid injections (ESI) in treating lumbar spine conditions?

Epidural Steroid Injections for Lumbar Spine Conditions

Direct Recommendation

Lumbar epidural steroid injections (ESI) are indicated ONLY for patients with true radiculopathy (pain radiating below the knee) who have failed 4-6 weeks of conservative therapy and have MRI-confirmed nerve root compression—they are NOT appropriate for axial low back pain alone. 1, 2

Clinical Indications

When ESI is Appropriate

• Radicular pain must extend below the knee—not just back pain or thigh pain—as this defines true radiculopathy requiring intervention 1, 3

• MRI must demonstrate nerve root compression, moderate to severe disc herniation, or foraminal stenosis that anatomically correlates with the clinical radicular symptoms 1, 2

• Clinical examination should document dermatomal sensory loss and positive straight leg raise test to confirm radiculopathy 1, 3

• Minimum 4-6 weeks of failed conservative therapy including physical therapy, NSAIDs, and activity modification must be documented before considering ESI 1, 2

When ESI is NOT Appropriate

• The American Academy of Neurology explicitly recommends AGAINST epidural steroid injections for non-radicular low back pain due to limited supporting evidence 1, 3

• Axial back pain from spinal stenosis, facet arthropathy, or degenerative disc disease without radiculopathy is not an indication for ESI 1, 2

• The 2025 BMJ guideline provides a strong recommendation AGAINST epidural injections for chronic axial spine pain, stating "all or nearly all well-informed people would likely not want such interventions" 1

Technical Approach Selection

Transforaminal vs Interlaminar Routes

• Transforaminal epidural steroid injection (TFESI) is more effective than interlaminar or caudal approaches for L5-S1 disc herniations with radicular pain, achieving complete pain relief in 30% versus 10% and 3% respectively at 24 weeks 4

• The transforaminal supraneural approach is most frequently selected by experienced practitioners for radicular pain at L4-L5 and L5-S1 levels 5

• TFESI delivers medication directly to the ventral epidural space where pathology typically occurs, explaining superior efficacy compared to other routes 4

Mandatory Fluoroscopic Guidance

• Fluoroscopic guidance is non-negotiable and must be used for all epidural injections to ensure proper needle placement and minimize complications 1, 2

• The American Society of Anesthesiologists strongly recommends image guidance for both interlaminar and transforaminal approaches with high-quality evidence 1

Treatment Protocol

Initial Injection Series

• Patients may receive 1-3 injections every 2 weeks as part of the initial treatment series 6, 4

• ESI must be part of a comprehensive multimodal pain management program including physical therapy, patient education, psychosocial support, and appropriate oral medications—not a standalone treatment 1, 2

Repeat Injection Criteria

• Repeat therapeutic injection is appropriate ONLY if the initial injection resulted in at least 50% pain relief lasting at least 2 months according to Spine Intervention Society criteria 1, 2

• Do not repeat injections based solely on patient request without objective evidence of prior benefit—this exposes patients to unnecessary risks 1

Expected Outcomes

Efficacy Data

• For lumbar disc herniations with radiculopathy, 77% of surgical candidates avoided surgery with average follow-up of 1.5 years after epidural steroid injection 7

• For spinal stenosis with radiculopathy, 44% of patients had long-term relief at 2 years and required no further treatment, while only 32% opted for surgery 8

• Transforaminal injections for discogenic radicular pain showed 59% of patients with greater than 50% improvement at one year, compared to 35% for spinal stenosis 6

• Pain scores improved significantly from baseline mean of 7.3 to 3.4 at 2 months, 4.5 at 6 months, and 3.9 at 12 months across all patient groups 6

Duration of Benefit

• Relief typically lasts from 2 weeks to 27 months, with most studies reporting assessment periods of 2 weeks to 3 months 1

• The evidence for chronic low back pain without radiculopathy supports only short-term relief of less than 2 weeks with Level III data quality 9

Safety Considerations

Mandatory Informed Consent Discussion

• Shared decision-making must include specific discussion of potential complications including dural puncture, insertion-site infections, cauda equina syndrome, sensorimotor deficits, discitis, epidural granuloma, and retinal complications 1, 2

• Rare catastrophic complications include paralysis and death, particularly with transforaminal injections 1

• Transforaminal injections carry higher risk than interlaminar approaches and require explicit discussion of the elevated risk profile 1

Steroid Selection

• Dexamethasone is the most frequently used steroid for both interlaminar (35.1%) and transforaminal (71.1%) epidural injections, reflecting a shift toward safety-oriented protocols 5

Common Pitfalls to Avoid

• Do not perform ESI for mechanical back pain from spondylosis, facet arthropathy, or hip pathology—these are not radicular conditions 1

• Do not ignore alternative pain generators such as sacroiliac joint pathology when physical examination suggests their involvement 1

• Do not proceed with ESI if imaging was performed more than 24 months prior—updated imaging is required to rule out new pathology 1

• Do not use ESI as a delay tactic before inevitable surgery—it should be part of comprehensive pain management with realistic goals 1

• The high dropout rates in studies (51-60% lost to follow-up) severely compromise conclusions about long-term efficacy for chronic low back pain without radiculopathy 9