An exploratory, uncontrolled, pilot study investigating the effects of subtalar joint manipulation on two outcome measures: weight bearing dorsiflexion range of motion and center of pressure excursion index
Faulty biomechanical foot function, excessive pronation or supination, has been implicated in the generation of various lower extremity overuse injuries. Central to the creation of these complex movements is the function of the subtalar joint. The subtalar joint also plays a role in producing joint coupling movements that facilitate the development of gross functional foot movements, such as weight bearing dorsiflexion. It is postulated that subtalar joint manipulation may be able to correct aberrant subtalar joint motion and re-establish proper joint coupling during functional lower extremity maneuvers. Considering the subtalar joint pronates to contribute to the development of weight bearing lower limb dorsiflexion, the weight bearing dorsiflexion lunge test may be used to study the effects of subtalar joint manipulation. Plantar pressure parameters, specifically the center of pressure excursion index (CPEI), has been used previously to study various foot and ankle movements and pathologies. This measure has the potential to be used to study the effects of subtalar joint manipulation on dynamic foot function. No studies to date have investigated the effects of subtalar joint manipulation. Consequently, there exist no studies in the literature that can be used to obtain a sample size estimate. It is the purpose of this uncontrolled, exploratory pilot study to evaluate the utility of 2 outcome measures (weight bearing dorsilfexion range of motion and center of pressure excursion index) to study the effects of subtalar joint manipulation on foot function and to obtain data to determine a sample size estimate for a larger study investigating the effects of subtalar joint manipulation on foot function.