Effectiveness of cushioning foot orthosis for Sepak Takraw players during roll spike landing : finite element analysis

Abstract

The aim of this study was to evaluate impact force reduction during roll spike landing in Sepak Takraw through provision of a cushioning foot orthosis through finite element analysis. A prototype cushioning foot orthosis was designed via computer software with a full-length polyethylene foam top layer, forefoot and medial longitudinal arch cushion with polyurethane foam and ethyl vinyl acetate (EVA) lateral midfoot and hindfoot second layer, and midfoot reinforcement by Podiaflex? as a base layer. The forefoot model was divided into 5 sections as hallux, 1st metatarsal head (MTH), 2nd MTH, 3rd- 4th MTH and 5th MTH. Each section had an applied mass and velocity as a roll spike landing. The experimental was finite element method (FEM) and input data consisted of material properties, plantar weight distribution in specific areas, and body weight 40 kg, 50 kg, 60 kg and 70 kg respectively, Impact force at the forefoot and deformation of cushioning foot orthosis was collected while impact force was compared with and without intervention. The cushioning foot orthosis reduced impact force during roll spike landing while great toe was the most reduction area. Meanwhile deformation of cushioning foot orthosis evidence that these cushioning foot orthosis design was suitable for weight 40 - 70 kg. However, first metatarsal head was the highest pressure and the most deform in all weight. The cushioning foot orthosis has the potential to reduce impact forces during roll spike landing in Sepak Takraw. However, results are from a computer simulation which mathematically predict the percentage of force reduction. Experiments of available material and its properties as well as clinical experimentation with athletes are recommended, to provide more reliability and validity of testing.