The Outcome of Epidural Injections in Lumbar Radiculopathy Is Not Dependent on the Presence of Disc Herniation on Magnetic Resonance Imaging: Assessment of Short-Term and Long-Term Efficacy.

Objective: Lumbar radiculopathy is a condition with major physical, social, and economic consequences. Despite its favorable prognosis, the burden can be significant. In this study, we aimed to determine the value of magnetic resonance imaging (MRI) and the efficacy of transforaminal epidural injections (TEIs) in patients with lumbar radiculopathy secondary to lumbar disc herniation (LDH) and other causes (non-LDH).

Methods: Patients with lumbar radiculopathy were reviewed for radiologic diagnosis based on MRI. For patients receiving TEI therapy, response after 6-8 weeks (short-term) and 16 weeks (long-term), number of injections, subsequent surgery, and patient outcome were evaluated. Treatment response was assessed by patient-reported symptom relief and numeric rating scale pain scores.

Results: Overall, 66% of MRI examinations showed a clinically relevant LDH. A total of 486 of 1824 patients received TEI, of whom one third did not show LDH. Of patients, 70% reported a short-term effect with significant pain reduction and 44% reported a long-term effect. No significant differences were observed between the LDH and non-LDH groups. Of patients, 59% required multiple injections and reported similar efficacy compared with patients treated with a single injection.

Conclusions: A considerable part of MRI examinations in patients with lumbar radiculopathy do not show a clinically relevant LDH. Regardless of the radiologic diagnosis, most patients treated with TEI benefit in both the short-term and the long-term after a single-injection or multiple-injection regime. Subsequent injections are advisable if the effect from the first injection is unsatisfactory or wears off. MRI examination before TEI therapy may be redundant, which allows for expedition of this treatment.