Figure 1

Selected gait parameters normalised for 100% stance (each graph is individually scaled and the gray band represents the mean ± 1 SD for the able-bodied adults and the solid line is the mean ± 1 SD error bars for the RA patients. A – Initial foot-to-floor and terminal stance heel rise angles during stance, measured as the angle of the plantar surface of the foot to the horizontal. Positive angles decreasing to zero indicate increasing foot-to-floor contact, zero indicates foot flat, and increasing negative angles indicate progressive heel rise; B – frontal plane motion of the rearfoot in the shank coordinate system during stance phase (+ inversion/- eversion); C – ground reaction forces normalised to body mass acting perpendicular to the plantar aspect of the foot; D – sagittal plane ankle joint power during stance).