Corticosteroid Use Questioned in Nerve Root Infiltration
In lumbar disc herniation, dexamethasone-lidocaine combination produces no added benefits
WEDNESDAY, April 9 (HealthDay News) -- In the non-surgical treatment of lumbar disc herniation with nerve root infiltration, corticosteroids show no additional benefit when combined with a local anesthetic, according to the results of an animal study published in the April issue of Spine.
Hisayoshi Tachihara, M.D., Ph.D., of the Fukushima Medical University School of Medicine in Fukushima, Japan, and colleagues exposed the left L5 nerve root and dorsal root ganglion in 174 adult female Sprague-Dawley rats. They treated the rats with nerve root infiltrations containing 1 percent lidocaine, 0.4 percent dexamethasone, a combination of lidocaine and dexamethasone, or saline.
The researchers found nerve root infiltration prevented mechanical allodynia. They also found no decreases or significant group differences in withdrawal thresholds amongst those receiving lidocaine, dexamethasone or a combination of the two. The expression of TNF-α in the dorsal root ganglia was found to be lower in these three groups compared to non-treatment with no significant differences seen among the three.
"The present study focused on TNF-α, which plays a crucial role in the development of nucleus pulposus-induced inflammatory changes in the nerve root," the authors write. "Our results suggest that corticosteroid is unnecessary for nerve root infiltration."