Anaesthetic and corticosteroid response immediately following epidural injection in patients with MRI confirmed lumbar disc herniation.

Abstract

Objectives: To describe a rapid, community-based assessment, referral and management system for acute symptomatic LDH. To identify and describe specific local anaesthetic and corticosteroid patterns of pain intensity change during the first week post-epidural injection.

Setting: Private practice, specialist physiotherapy clinic, community-based radiology facility.

Design: Cohort study.

Method: Consecutive patients with clinical and MRI diagnosis of acute LDH causing radicular pain and/or radiculopathy were referred for lumbar epidural injection. Pre- and post-procedure measures of back, buttock and lower limb pain intensity were acquired at 1,2,4,6 h, and at 1 week. Analysis of changes in back, buttock and lower limb pain intensity to identify different patterns that may influence clinical management.

Results: A detailed clinical assessment, MRI and epidural steroid injection was completed for 51 patients. Pain intensity change patterns were highly heterogeneous. Three broadly different pain intensity response patterns: "Steroid Responsive" (41%), "Mechanical" (37%) and Unconfirmed Diagnosis (22%), were identified. Psychosocial factors did not influence tendency of patients to follow one clinical pathway versus another.

Conclusions: Radicular pain associated with LDH responds to epidural injection in patterns that may be described as "steroid responsive" or "mechanical". LDH is not confirmed as the cause of pain in the remainder. Immediate post procedure anaesthetic and one week corticosteroid responses can guide management pathway and identify a subgroup requiring further diagnostic workup.