Spatiotemporal parameters and gait variability in people with psoriatic arthritis (PsA): a cross‐sectional study

Abstract Background Foot involvement is a major manifestation of psoriatic arthritis (PsA) and can lead to severe levels of foot pain and disability and impaired functional mobility and quality of life. Gait spatiotemporal parameters (STPs) and gait variability, used as a clinical index of gait stability, have been associated with several adverse health outcomes, including risk of falling, functional decline, and mortality in a wide range of populations. Previous studies showed some alterations in STPs in people with PsA. However, gait variability and the relationships between STPs, gait variability and self‐reported foot pain and disability have never been studied in these populations. Body‐worn inertial measurement units (IMUs) are gaining interest in measuring gait parameters in clinical settings. Objectives To assess STPs and gait variability in people with PsA using IMUs, to explore their relationship with self‐reported foot pain and function and to investigate the feasibility of using IMUs to discriminate patient groups based on gait speed‐critical values. Methods Twenty‐one participants with PsA (age: 53.9 ± 8.9 yrs.; median disease duration: 6 yrs) and 21 age‐ and sex‐matched healthy participants (age 54.23 ± 9.3 yrs) were recruited. All the participants performed three 10‐m walk test trials at their comfortable speed. STPs and gait variability were recorded and calculated using six body‐worn IMUs and Mobility Lab software (APDM®). Foot pain and disability were assessed in participants with PsA using the foot function index (FFI). Results Cadence, gait speed, stride length, and swing phase were significantly lower, while double support was significantly higher, in the PsA group (p 0.57, p