LAUSR

Ankylosing Spondylitis (AS) is a systemic inflammatory disease of unknown origin. It affects mainly males. Chronic inflammatory back pain is the commonest presenting symptom and regularly develops between 20 and 40 years age. AS can likewise, have extra-articular manifestations. These manifestations commonly develop after the onset of axial symptoms but hardly can precede them. Even though AS is a systemic disease, the presenting symptoms, treatment, and morbidity are largely dependent on spine affection. Epidural injections for managing chronic low back pain are one of the most frequently performed interventions in the United States. Friedly et al reported administration of epidural injections in 36% of patients with axial low back pain. However, there is no clinical evidence for the use of epidural injections in axial SPA and most recommendations are limited to radicular pain with disc herniation. The evidence for caudal epidural injections is Level I in managing pain secondary to disc herniation and radiculitis. To our best of knowledge, this is the first study evaluating the role of caudal epidural steroid and lidocaine injections in managing pain and function of the spine in radiographic axial SPA.To evaluate the significance of caudal epidural injections in controlling pain and spinal stiffness in radiographic axial SPA.In our study 32 Patients were included. They were randomly doled out into 2 equivalent groups; Group I received caudal epidural injections ultrasound guided with 1% lidocaine hydrochloride (xylocaine, AstraZeneca) 9 mL mixed with 1 mL of triamcinolone 40 milligrams (Kenacort, Bristol Myers Squip), whereas Group II did not receive. Both groups were matched regarding age, sex and disease duration (table) and both were under treatment with anti TNF and NSAIDs with or without sDMARDs. All participants fulfilled the ASAS criteria for radiographic axial SPA. Outcomes measures included: visual Analogue Scale (VAS), and ASDAS score with assessment at baseline, 2 weeks and 8 weeks post-treatment. Significant pain relief was defined as 50% or more or no pain. ASDAS improvement is considered when the score reduction ≥ 1.1.There was a significant difference between both groups regarding pain (Figure 1) and ASDAS scores (Figure 2) in favor of group I. This effect was maximum after 2 weeks interval. More than two thirds of the cases (68.8%) had significant pain relief among group 1, compared to only 18.8% among group 2. Despite the decline of this effect after 8 weeks, still the difference significant between both groups. Shorter disease duration and older age of onset were associated with better outcomes among group 1 but not group 2. However, these correlations were non-significant.Figure 1.Change of VAS between the two groups.Figure 2.Change of VAS between the two groups.Caudal epidural injection is cheap, effective and practical technique in controlling pain and stiffness of the spine in radiographic axial SPA with acceptable complications and relatively sustained effect. Studies including bigger number of participants and longer span of follow up still required.Table.Comparison between the two groups as regards demographic and outcome dataItemGroup 1Group 2P valueAge40.31±4.5438.88±5.440.423SexMale10(62.5%)9(56.2%)0.719Female6(37.5%)7(43.8%)Disease duration(in years)3.13±1.483.22±1.240.847VASAt baseline7.88±0.817.75±0.770.658After 2 weeks4.06±0.686.13±1.54<0.001After 8 weeks4.44±0.636.56±1.21<0.001% improved at 2 weeks11(68.8%)3(18.8%)0.004% improved at 8 weeks6(37.5%)2(12.5%)0.102ASDASAt baseline3.62±0.513.58±0.370.814After 2 weeks2.50±0.533.04±0.710.020After 8 weeks2.72±0.523.13±0.550.036% improved at 2 weeks10(62.5%)3(18.8%)0.012% improved at 8 weeks7(43.8%)2(12.5%)0.057NoneNone declared