Measurement Of The Frontal Plane Rearfoot Attitude
The Rearfoot Measurement Device consists of an acrylic plate positioned over the posterior aspect of the leg and heel. It presents a scored midline for referencing the posterior midline of the calf and a movable pointer arm which records the position of the heel reference line (Tuber Axis).
With the scored plate midline positioned over the posterior midline of the calf, the subtalar joint is firmly supinated, as reflected by heel inversion. The movable pointer arm is centered over the heel and the protractor dial is read and recorded. Then with the subtalar joint firmly pronated, the everted protractor reading is entered into the biometry record.
Finally, with the subject in the relaxed stance attitude, the measuring device is placed on end behind the posterior aspect of the leg and foot . In this position, two things are accomplished. First, the “relaxed calcaneal stance position” can be measured using the protractor at the bottom of the plate. Then, with the subtalar joint in its “neutral position”, the movable pointer is used to determine the frontal plane slant of the tibia, or “tibial varum” angle.