A Randomized Clinical Trial of Three Different Steroid Agents for Treatment of Low Backache through the Caudal Route

Although epidural steroids are commonly used for conservative management of sciatica, controversies exist regarding optimal approach, type and dose of steroids, volume of injectate and frequency of administration. This randomized comparative blinded study was undertaken to compare the efficacy of caudal methylprednisolone acetate with triamcinolone acetonide and dexamethasone acetate, for pain relief for sciatica associated with lumbar-disk herniations.

A Total of 163 patients with radicular pain due to lumbar-disk herniations, between 27-70 years of age were randomly divided into four groups: three were given epidural steroid injection therapy (methylprednisolone acetate, triamcinolone acetonide and betamethasone acetate) with bupivacaine; one group received bupivacaine alone via caudal approach. Injections were repeated every three weeks till a total of 210 mg of methylprednisolone (and equivalent) or three injections. Pain relief, disability and activity levels were assessed at 3, 6, 9 and 12 weeks interval.

Pain relief was present in all four groups by three weeks with no difference between the groups (p=0.006; 0.005; 0.0045; 0.005 respectively to baseline). By the 6 and 12 week, the three steroid groups had significant pain relief (p<0.001). Among these, both methylprednisolone and triamcinolone groups showed greater improvement in the finger-to-floor distance (p=0.006). A smaller proportion of patients in this group had residual sensory deficits (p=0.03) as compared to dexamethasone but difference was statistically insignificant. Overall pain relief was significantly better at all follow-up evaluations in the steroid group than in the control group (p<0.001 at all evaluations).

Short-term improvement in leg pain and sensory deficits was observed in patients with sciatica due to a herniated nucleus pulposus with both epidural bupivacaine and steroids. All long-acting steroids had no statistically significant difference between their efficacy in pain relief but methylprednisolone and triamcinolone were more effective by the second injection as compared to dexamethasone which required a third injection in a significant number of cases. Differences between methylprednisolone and triamcinolone were insignificant. Complications were negligible and temporary.