Does Electrodiagnostic Confirmation of Radiculopathy Predict Pain Reduction after Transforaminal Epidural Steroid Injection? A Multicenter Study
Zachary McCormick, Daniel Cushman, Mary Caldwell, Benjamin Marshall, Leda Ghannad, Christine Eng, Jaymin Patel, Steven Makovitch, Samuel K Chu, Ashwin N Babu, David R Walega, Christina Marciniak, Joel Press, David J Kennedy, Christopher Plastaras, Zachary McCormick, Daniel Cushman, Mary Caldwell, Benjamin Marshall, Leda Ghannad, Christine Eng, Jaymin Patel, Steven Makovitch, Samuel K Chu, Ashwin N Babu, David R Walega, Christina Marciniak, Joel Press, David J Kennedy, Christopher Plastaras
Abstract
Objective: Minimal definitive literature identifies patients with radicular pain who would benefit most from epidural steroid injection (ESI). This study investigated if electromyographic (EMG) confirmation of radiculopathy with active or chronic denervation predicts a positive treatment outcome following ESI.
Design: Longitudinal cohort study of adults who underwent EMG and subsequent transforaminal ESI within 6 months. The proportion of individuals who experienced >50% pain relief and mean change in daily morphine equivalents (DME) were calculated.
Results: 170 individuals with respective mean (Standard Deviation) age and duration of symptoms of 55 (15) years and 36 (56) months were included. Mean time to <30 day and >30 day follow-up post-injection were 18 (6) and 99 (130) days, respectively. At >30 day follow-up, a larger proportion of EMG-confirmed individuals (37.7%) reported >50% pain reduction compared to EMG-negative individuals (17.8%) (p=0.03). This was significant for lumbosacral (40% vs. 15%, p=0.01) but not cervical symptoms (p>0.05). Mean decrease in DME at long-term follow-up in EMG-confirmed compared to EMG-negative individuals trended toward significance (-4 vs. -1, p=0.11). There was no significant relationship between myotomal spontaneous activity and pain or opioid use.
Conclusions: Needle EMG predicts long-term pain reduction from transforaminal ESI in patients with lumbosacral radiculopathy, regardless of the presence of active denervation.
Keywords: Electromyography; Prediction tool; cervical; epidural; lumbar; lumbosacral; pain; radiculopathy.
Conflict of interest statement
Conflict of interest: Dr. Plastaras has a patent RICPLAS licensed. None of the other authors report any conflict of interest.
Source: PubMed