The Relation Between Injection Volumes and Efficacy of Epidural Steroid Injections in Treatment of Acute Low Back Pain

Background: Low back pain (LBP) is one of the most common complaints that is reported by all age groups. Objective: This study was aimed to investigate the efficacy of epidural steroid injections (EPSI) related to different volume injections for treatment of acute low back pain with radiculopathy. Patients and Methods: The study is consisted of seventy five patients who had acute discogenic pain. Three groups composed namely Group 1, Group 2 and Group 3. All patients were assigned to one of the groups randomly and recevied combination of triamcinolone (80 mg) and bupivacaine (12.5 mg) as a single epidural dose. Volume of 10 mL, 15 mL, and 20 mL epidural injections were used for Group 1, 2 and 3 respectively. The efficacy of treatment was assessed with visual analog scale; VAS (O = no pain, 10 = unbearable pain) straight leg elevation test; SLET (0° = worst, 85° = best), and oswestry disability index; ODI (0 to 20%: minimal disability, 80 to 100%: bed bound patients) before and 2 weeks after the epidural steroid injections (EPSI). Results: Fifty seven 57 (76%) female and 18 (24%) male were entered to the study. Two weeks after the procedure, significant improvement was observed in each group regarding the results of VAS, SLET and ODI. Temporary radicular pain, not required treatment, was reported for 10 patients; 40% of group II and 18 patients; 72% of group III, but not reported in group I (P < 0.001). Conclusions: Different volumes of EPSI in patients with acute low back pain associated with radiculopathy causes significant pain relief in all groups. There was no superiority between the groups. Temporary radicular pain we encountered can be explained by high volumes.