Step Performance in Persons With Rheumatoid Arthritis: A Case-Control Study

Abstract Smulders E, van Lankveld W, Eggermont F, Duysens J, Weerdesteyn V. Step performance in persons with rheumatoid arthritis: a case-control study. Objective To investigate factors that could lead to falls in patients with rheumatoid arthritis (RA). Design Case-control study. Setting Hospital. Participants Patients with RA (n=15) and age- and sex-matched controls (n=15; mean ± SD age, 60.5±7.1y). Interventions Not applicable. Main Outcome Measures Performance of participants on a step task. Furthermore, manual performance was assessed, as well as questionnaires for balance confidence, fear of falling, and activity level. Results Patients with RA showed nonsignificantly increased RTs (time to anticipatory postural adjustment and foot lift) and significantly increased movement times (MTs). Push-off force and step velocity were significantly lower in patients with RA. During a manual task, delayed RTs and MTs were seen. Moreover, lower levels of balance confidence and more fear of falling were reported in patients with RA. There were no differences in activity levels. Conclusions When performing a quick step, patients with RA show delayed MT and step velocity and decreased push off. Because quick stepping often is used to avoid falls, the increase in step execution time might have undesirable consequences. Furthermore, patients with RA have lower balance confidence and more fear of falling than healthy controls; these factors also contribute to higher fall risk.