Needle electromyography predicts outcome after lumbar epidural steroid injection

Introduction: Needle electromyography (NEE) would be more valuable if it could predict outcomes after lumbar epidural steroid injections (LESIs) in lumbosacral radiculopathy (LSR). Methods: We investigated the predictive value of NEE for outcome after LESI compared with other known predictive variables in 89 subjects with clinical LSR. Seventy patients completed the study, which included diagnostic lower extremity NEE and LESI. Outcome measures included changes in pain, physical function, and psychosocial function [assessed using the Pain Disability Questionnaire (PDQ)]. Results: NEE was an independent predictor of long-term pain improvement after LESI and was not predictive of PDQ functional improvement. A regression model, with NEE as one of several independent variables, showed strong outcome-predictive ability. Conclusions: NEE is an independent predictor of long-term pain relief after LESI for LSR. Abnormal NEE is predictive of better outcome than normal NEE. A regression equation including NEE and other independent predictors was predictive of pain and functional outcomes.