Clinical value of transforaminal epidural steroid injection in lumbar radiculopathy.

Objectives: To identify the diagnostic, therapeutic, and prognostic values of transforaminal epidural steroid injection as interventional rehabilitation for lumbar radiculopathy. Design: Case series. Setting: Regional hospital, Hong Kong. Patients: A total of 232 Chinese patients with lumbar radiculopathy attributed to disc herniation or spinal stenosis received transforaminal epidural steroid injection between 1 January 2007 and 31 December 2011. Interventions: Transforaminal epidural steroid injection. Main outcome measures: Patients' immediate response, response duration, proportion of patients requiring surgery, and risk factor's affecting the responses to transforaminal epidural steroid injection for lumbar radiculopathy. Results: Of the 232 patients, 218 (94.0%) had a single level of radiculopathy and 14 (6.0%) had multiple levels. L5 was the most commonly affected level. The immediate response rate to transforaminal epidural steroid injection was 80.2% in 186 patients with clinically diagnosed lumbar radiculopathy and magnetic resonance imaging of the lumbar spine suggesting nerve root compression. Of patients with single-level radiculopathy and multiple-level radiculopathy, 175 (80.3%) and 11 (78.6%) expressed an immediate response to transforaminal epidural steroid injection, respectively. The analgesic effect lasted for 1 to <3 weeks in 35 (15.1%) patients, for 3 to 12 weeks in 37 (15.9%) patients, and for more than 12 weeks in 92 (39.7%) patients. Of the 232 patients, 106 (45.7%) were offered surgery, with 65 (61.3%) undergoing operation, and with 42 (64.6%) requiring spinal fusion in addition to decompression surgery. Symptom chronicity was associated with poor immediate response to transforaminal epidural steroid injection, but not with duration of pain reduction. Poor response to transforaminal epidural steroid injection was not associated with a preceding industrial injury. Conclusions: The immediate response to transforaminal epidural steroid injection was approximately 80%. Transforaminal epidural steroid injection is a useful diagnostic, prognostic, and short-term therapeutic tool for lumbar radiculopathy. Although transforaminal epidural steroid injection cannot alter the need for surgery in the long term, it is a reasonably safe procedure to provide short-term pain relief and as a preoperative assessment tool.