Measurement Of First Ray Range Of Motion And Rearfoot Stance Position
This dual purpose device is utilized for the determination of the first ray range of motion and position and also for the assessment of subtalar joint supination or pronation in the relaxed and neutral stance positions.
With the subject prone or supine, the foot and ankle are placed in their neutral position attitude. The Segmometer is then positioned beneath the metatarsophalangeal joints (as shown).
For evaluation of first segment sagittal plane range of motion, the first ray is dorsiflexed and then plantarflexed, whereupon the displacements are read directly from the centerline zero of the millimeter scale of the device.
As a “Stance Pronimeter”, the device is turned on its side and placed next to the lateral malleolus as shown. The sliding arm is then adjusted to contact the lateral malleolus for an indication of ankle displacement relative to the lateral aspect of the heel. This “lateral malleolar index”of abnormal pronation or supination during relaxed stance can then be compared with more normalized alignment through orthosis intervention.