A Supination Resistance Measuring Device that assists the practitioner to determine that amount of support or arch height needed in an orthotic to reduce patient symptoms.
Supination resistance as a term was first used by a podiatrist, Dr Kevin Kirby DPM, in 1992. The term was used to describe the force that is needed to supinate the foot. The test is described as placing two fingers under the medial posterior aspect of the arch of the foot and then manually supinating the foot. An estimate is made of how hard to easy that the test is. The assumption is that if the test is hard to do, then there is a lot of force pronating the foot and could be a risk factor for a number of different pathologies. If the force is high, then more force is needed to come from the foot orthotic to counter that high force coming from the foot. If the force is low, then less force is needed to come from the foot orthotic. If the force from a foot orthotic is too low compared to the supination resistance force, then the assumption is that the foot orthotic is likely to be less effective. If the force from the foot orthotic is too high compared to the supination resistance force, then the assumption is that this might oversupinate the foot and cause other problems.
The Keystone device is the first commercially available device for clinicians to quantify the supination resistance value so they can make better clinical decisions and better communicate with other clinicians.