Objective: To assess the impact of ultrasonography (US) on local corticosteroid (CS) injections of painful ankle, hindfoot, and midfoot in chronic inflammatory diseases.
Methods: Consecutive patients with chronic rheumatic diseases admitted to the hospital for local CS injections of painful ankle, hindfoot, or midfoot were enrolled in this study. Clinical and radiographic evaluation was performed by the physician in charge of CS injections, and US examination was performed by an independent examiner blinded to the clinical and radiologic findings. According to a randomized weekly-periods design, the physician planned CS injections either aware (G1 group) or unaware (G2 group) of US results. In the latter case, he was nonetheless informed of US results after he had performed the injections. Impact of this information on the treatment planning was assessed in all cases. Prognostic impact of US was also evaluated by comparing the change in global assessment of efficacy of CS injections, in activity of the disease, and in the Western Ontario and McMaster Universities (WOMAC) subscales after 1 and 3 months, between G1 and G2 groups.
Results: The knowledge of US findings led the physician to change his decision of local CS injections in 56 (82%) of 68 patients studied. Among 1,131 assessed sites, by clinical, radiographic, and US evaluation, injection was cancelled in 37 (15%) of 242 proposed sites, whereas it was decided in 74 (8%) additional sites. After 1 month, there was an improvement in G1 as compared with G2 groups. The mean +/- SD change in WOMAC physical function subscale was 15.6 +/- 17.5 in G1 versus 8 +/- 13 in G2 (P = 0.0305). After 3 months, only the global assessment of efficacy of CS injections was statistically greater in G1 than in G2 group (P = 0.0170).
Conclusion: US frequently led the physician to change his diagnosis of inflammatory lesions in painful foot, and consequently his planning of CS injections. Moreover, US could improve the response to local treatment.