The benefit of an intradiscal injection of corticosteroids for low back pain with active discopathy is not totally resolved.

The objective of this study was to estimate the clinical efficacy of an intradiscal injection of glucocorticoids versus lidocaine in patients with low back pain and active discopathy (Modic 1 changes).

A prospective, single-blind, randomized controlled study was conducted in 2 tertiary care centers with spine units. We enrolled 50 patients (mean age 50 years; 46% women) with lumbar active discopathy on MRI and failure of medical treatment for more than 6 weeks. Participants were randomly assigned to receive an intradiscal injection of glucocorticoids [50mg prednisolone acetate (GC group), n=24] or lidocaine [40mg (L group), n=26] by senior radiologists. Outcome measures were low back pain in the previous 8 days (10-point visual analog scale), Dallas Pain Questionnaire, Oswestry Disability Index, analgesic treatment and work status at 1, 3 and 6 months as well as pain at 1, 2 and 3 weeks. The primary outcome was change in pain between baseline and 1 month.

Data for 39 patients (78%; 17 in the GC group, 22 in the L group) were analyzed for the primary outcome. Pain intensity was significantly reduced at 1 month in the GC versus L group [mean (SD) −2.7 (2.3) and +0.1 (2.0), P<0.001] but not at 3 and 6 months. At 1 and 3 months, the groups significantly differed in daily activities of the Dallas Pain Questionnaire in favour of the GC group. The groups did not differ in consumption of analgesics or professional condition at any time. No serious intervention-related adverse events occurred. Study limitations included patients lost to the study because of injection-related technical issues in the L5/S1 disc and short time of follow-up.

As compared with intradiscal injection of lidocaine, intradiscal injection of prednisolone acetate for low back pain with active discopathy may reduce pain intensity at 1 month but not at 3 and 6 months.