Figure 2. The infrared marker cluster system used in this study to capture 3D foot motions.

(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.