The Efficacy Of Orthopaedic Insole In Metatarsalgias’ Gait Biomechanic Characteristics

Objective:Metatarsalgia is one of foot deformities in clinic,it shows forefoot pain when poople walk. Foot pain may affect normal gait, unnormal gait may increase the risk and decrease physical activity. Insoles are used to treat the metatarsalgias, as one of effective methods. The research is to find if the insoles are effective to the metatarsalgias and explore the biomechnic mechnics of its treatment.Methods:Eight women patients with secondary metatarsalgia from Beijing Wangjing Hospital participated in this study. Experiment concluding VAS subjective measurement, three dimensional kinematics (Motion Analysis Raptor-4, USA) and dynamics (Kistler9281CA, Switzerland) measurement, planta pressure distribution (Footscan plate system, Belgium) measurement was taken in Beijing Sport University Research Center.1. Every subject was gived one pair of insoles that fit their sizes, Visual analog scale(VAS) scares of pain were obtained from all subjects before treatment and one time every week after wearing orthopaedic insoles, totally five times.2. Their normal walking gait was measured by three dimensional kinematics and dynamics and plantar pressure distribution under two condition of barefoot and wearing insoles. The first time of test time is before treat, the second time of test is after four weeks. Statistical analysis was performed using SPSS.Results:1, Orthopaedic insoles is effecive to decrease forefoot pain for the metatarsalgias, the VAS score after four weeks decreased 84.9% than the first time (p<0.01).2, Compared with bare foot, at the moment of heel contect, the foot plantar flexion angle decreased(p=0.005), the foot eversion angle decreased(p=0.047);the maximum force moment of ankle increased (p=0.028). the peak force under the sencond and third metatarsal bone all decreased(p=0.032, p=0.013), the peak force under midfoot increased(p=0.003),the peak pressure under the sencond and third metatarsal bone all decreased(p=0.015, p=0.013), the impulse of the third metatarsal bone decreased(p=0.008), impulse of the midfoot increased (p=0.003).3, Compared with the first test, the second test showed that:the foot maximum eversion torque decreased(p=0.000). the first peak and second peak of vertical ground reaction force all decreased(p=008, p=002).Conclusion:1, Orthopaedic insoles decreased the matatarsalgias’ subjective pain.2,the metatarsalgias’over eversion at the moment of heel contact increased the risk of injury.3, the foot eversion angle decreased at the moment of heel contact when wearing orthopaedic insoles, so wearing orthopaedic insoles could decreas the risk of injury. 4, The excessive force under metatarsal bone caused metatarsalgias’pain, orthopaedic insoles redistribute the forefoot’peak force, peak pressure, midfoot’s peek force and impluse increase, metatarsal bone’s force decrease, subjective pain decrease.