Plantar force deviations in dynamic pedobarography – The role of insole and platform based systems as influencing factors

Summary Background Pedobarography systems have been used in numerous studies and have become an important tool for the evaluation of foot loads during sports activities. The aim of this study was to provide a valid comparison of plantar force patterns obtained with insole based and platform based systems. Material and methods 14 healthy participants were recruited from the medical faculty. A total of two trials were performed. Firstly the participants walked on the platform under barefoot conditions (emed ® -n50 platform, novel Inc., Munich, Germany). The second trial used a "neutral-shoe" with an in-shoe measurement system (Pedar ® X system, novel Inc.). Peak force values were analysed from four foot regions. Results For all foot portions, forces on the platform were significantly lower than the corresponding in-shoe values, excepting the toes ( p =0.11) and metatarsal heads ( p =0.067) of the non-preferred foot. The biggest difference was observed for the midfoot (preferred foot: 24%, non-preferred foot: 33%). Forces under the metatarsal heads displayed the smallest difference between the systems (preferred foot: 10% ( p p =0.067)). Conclusion Absolute maximum force values from platforms cannot be equated to those from sensor-loaded insoles. Interpretation and comparison of pedobarographic data should be performed cautiously if different systems are chosen. Level of Evidence IV, Case series.