Assesment of efficacy of local steroid injection for heel enthesitis in patients with seronegative spondyloarthropathy: A serial ultrasound study

Abstract

Introduction: Corticosteroid injection for heel enthesitis in SpA is controversial. We studied soft tissue changes at symptomatic heel enthesitis, by ultrasound examination and compared VAS pain score and USG findings, at baseline and 6 weeks after local corticosteroid injection. Methods: SpA patients with symptomatic heel enthesitis, refractory to 6 weeks of full dose NSAIDs, were offered local corticosteroid injection. Heel entheses were examined by USG before and 6 weeks after injection. Standard OMERACT definitions were used to define enthesitis, Achilles tendon >5.2 mm and plantar fascia >4.4 mm thick at 2 cm proximal to insertion, were considered thickened). Results: Forty two symptomatic entheses were examined by USG in 32 patients, which included 22 right and 16 left tendoachilles, 1 right and 3 left plantar fascia. Mean age of patients was 29.2 years, 29 were males. Cohort included 17 patients with Ankylosing SpA, 7 with JIA-ERA and 2 each with IBD associated Arthritis, PsA, ReA and Undifferentiated SpA. Sixweek followup (post-injection)wasavailable for 26patients.All patients reported improvement in Pain on VAS after injection (p<0.0001), which correlated with USG findings. There was significant reduction in entheseal thickness (p<0.0001), power Doppler signal (p<0.0001), peritendinous edema (p1⁄40.002), bursitis and bursal vascularity (p1⁄40.003 and <0.0001 respectively). There was no change in bone erosions and enthesophytes. None of the patients had injection related complications at 6 weeks of follow up. Conclusions: This study confirms the clinical and sonographic efficacy of local steroid injection for refractory heel enthesitis in patients with SpA