Ultrasound-guided epidural block in axial spondyloarthritis patients with limited spine mobility: a randomized controlled trial

BACKGROUND: Evaluation of the effectiveness of caudal epidural injection on pain, spine mobility, disease activity, and activity of daily living in axial spondyloarthritis (SpA) patients. METHODS: A total sample of 47 patients were registered in this study. They were randomly assigned into 2 groups; Group I received caudal epidural injections, ultrasound-guided, with 1% lidocaine hydrochloride mixed with triamcinolone, whereas Group II did not receive any injections. All participants fulfilled the ASAS criteria for axial SpA. Outcome measures were as follows visual analogue scale, Oswestry disability index (ODI), modified Schober test, lateral lumbar flexion, and Ankylosing Spondylitis Disease Activity Score (ASDAS) with assessment at baseline, 2 weeks, and 8 weeks post-treatment. This clinical trial was registered on clinicaltrials.gov under the number NCT04143165. RESULTS: There was a significant difference between both groups regarding pain, ODI, spine mobility and ASDAS scores in favor of group I. This effect was at its maximum after 2 weeks. Despite the decline of this effect after 2 months, the difference between the groups remained significant. Higher disease activity, younger age, and shorter disease duration were associated with better outcomes. CONCLUSIONS: Epidural injection of lidocaine and triamcinolone is a cost effective and a practical technique for controlling pain, as well as improving the function of the spine and disease activity scores in axial SpA patients with acceptable complications and relatively sustained effect.