The Influence Of Proprioceptive Training On Foot Pressure Of People With Ankle Joint Injury History

In this research we recruit20people with chronic unstable ankle, which includes12male and8female. They are asked to do proprioceptive training3times each week, totally6weeks according to planned program. The exercises they performed are single leg standing-open eye, single let standing-closed eye, single leg standing on Balance Pad-open eye, single leg standing on Balance Pad with arm swing-open eye, single leg standing on Balance Pad with arm and leg swing-open eye. We did test of their gait before and after training using the foot scan system developed by RS-Scan to compare the changes of their dynamic characteristic of foot pressure before and after training.The results show that:pressure ratio of medial to laterial foot before and after intervention comparison has a significant difference (P<0.01); X-COP of first metatarsal contact(FMC), forefoot flat(FFF) and heel off(HO), and the maximum value of X-COP in initial contact phase(ICP), forefoot contact phase(FFCP) and foot flat phase(FFP), and the minimum value of X-COP in forefoot contact phase(FFCP) and forefoot push off phase(FFPOP) are all having a significant differences (P<0.01). The X-COP of first foot contact (FFC) and the minimum value of X-COP in initial contact phase(ICP) and foot flat phase(FFP) have differences (P<0.05). Pmax of big toe and first metatarsal increased after training, of which the increase of Pmax of big toe has a significant differences (P<0.01), increase of Pmax of first metatarsal has differences (P<0.05). The absolute and relative impulse of big toe and the first metatarsal were increased after training, while the absolute and relative impulse of second to the fifth metatarsal was reduced. Among which only the absolute impulse of fourth metatarsal has differences (P<0.05), others all have significant differences (P<0.01). The absolute impulse of medial and lateral heel were decreased after training, the change was not significant. Relative impulse were increased after training, with a significant difference (P<0.01). The percentage of first contact of fourth and fifth metatarsal have differences (P<0.05), while the percentage of first contact of medial and lateral heel have a significant difference (P<0.01). The results of research shows that the inversion angle of foot first contact changes significantly, after proprioceptive training foot contact floor in a more neutral position. Proprioceptive training has significant influence of the function of big toe and first metatarsus, which can probably influence grip and stability of foot. In the whole foot contact process, shift of the center of pressure are all toward the middle axis which indicates that feet become more stable after training. The impulses of different areas of feet re-locate after training, the impulse of first metatarsus increases significantly and those of other metatarsus decrease. The work done by first metatarsus and the heel increase, that done by second to fifth metatarsus decrease. The ability of controlling is increased in the medial part of forefoot. After training the laterial part of forefoot contacts floor delayed, heel contacts floor also delayed, which helps increase the time to feeling the ground of the feet, therefore increase stability of the feet.