Pedobarographic gait analysis on male subjects

Abstract

Numerous studies have been conducted on human and animal walking gait. Recent studies utilize data acquisition systems; such as, force plates, video cameras, tread mills, infrared detection, digital imaging and insole sensors. The pedobarograph fits into the last acquisition method. This study was conducted using a Novell Pedar/sup R/ in-shoe pedobarographic system. The sensors are imbedded between two soft thin pads. The pad covers the bottom of the foot and is inserted into the shoe between the foot and shoe's bottom. Each pad has 99 capacitance sensors connected to a computer data acquisition system. The advantage of this system over similar systems is its ability to map the gait pattern during normal walking conditions. The sensors are externally calibrated and insensitive to temperature changes. These factors make the system ideal for collecting data inside a shoe. A gait study was conducted utilizing the Pedar system to measure walking gait on human male subjects with overpronated (fallen arches) feet. Each subject was evaluated by a podiatrist for foot type characteristics. After each subject was fitted with the sensor pads, they walked a given course five times while data were recorded. The sensor's output data were divided into ten zones or masks and averaged. The divisions included two in the heel, three in the arch, three in the forefoot and two in the toe area. Data analysis examined the masks for the left and right feet separately. The results are presented in the form of graphs and statistical parameters. Various parameters were examined to determine patterns to categorize the extent of overpronation. Some of the parameters examined were the dynamic pressure line, length of contact phase, energy dissipation, bottom of the foot pressure variations and gait velocity. The conclusions drawn from the study are that the degree of pronation can be cataloged using the energy dissipation as it is related to the stride time and the pressure pattern during foot contact. Subjects with overpronation in either foot have a tendency to walk on the medial portion of the foot thereby expending more time and energy in their walking gait.