The infrared marker cluster system used in this study to capture 3D foot motions.

<p>(A)The foot was divided into five segments including hindfoot, midfoot, medial and lateral forefoot and toes. A set of thermal plastic plates, each carrying four infrared markers was mounted firmly on each segment to capture the segmental motions. A number of hemispherical infrared markers were also attached on the anatomical landmarks. (B) The configuration of the rigid marker cluster and the hemispherical marker.