ANALYSIS OF LONGITUDINAL ARCH SUPPORTS IN STABILIZING THE ARCH OF THEFOOT

Two orthotic devices commonly prescribed as arch supports were studied to evaluate their efficacy in stabilizing the foot. Fourteen cadaveri c feet were mounted in a loading frame, and an axial load of 222, 445, or 667 N was applied while three-dimensional positions of the talus, calcaneus, navicular, and first metatarsal were monitored with a magne tic tracking system. Feet were tested with and without the use of two commonly prescribed arch supports. The two indices used to assess arch stabilization were arch height and joint rotation. Joint rotations co nsistently increased on load application. Significant differences were observed with Inserts 1 and 2 in metatarsal talar abduction, dorsifle xion and eversion, calcaneal talar eversion, and talar tibial dorsifle xion. Arch height significantly increased with both inserts. Contrary to previously published results, the arch supports that were studied p rovided measurable improvement in arch stability in a simulated standi ng at ease position.