Figure 1. Ultrasound tracking of calf muscles during standing.
- The newly constructed balance platform is depicted in A). The ultrasound probe from the new Toshiba Aplio 500 machine is shown attached to the left medical gastrocnemius.
- B) shows the resulting ultrasound image, with the red lines depicting the matlab-tracked fascicle length.
- C) shows ankle angle (blue) and muscle fascicle length (red) during a period of voluntary sway in the sagital plane.
- The cross-correlation between ankle angle and muscle length is shown in D). The strong negative correlation represents ‘paradoxical’ muscle movement, ie; during forward sway the muscle shortens.
- E) and F) depict the same graphs for a period of normal quiet standing.