Variability of plantar pressure data - A comparison of the two-step and midgait methods

The number of trials required to obtain a reliable representation of the pl antar pressure pattern is an important factor in the assessment of people w ith insensate feet or the use of plantar pressure data as a basis for fabri cation of foot orthoses. Traditionally, the midgait method has been used fo r the collection of pressure data, but the large number of walking trials r equired by this method can increase the risk of injury to the plantar surfa ce of the insensate foot. As a result, the two-step method of plantar press ure data collection has been advocated. The purpose of this investigation w as to determine the degree of variability in regional plantar pressure meas urements using the midgait and two-step methods of data collection. Plantar pressure data were collected from ten volunteers (five men and five women) between the ages of 20 and 35 years in 20 trials using both data-collectio n protocols. The results of the study indicate that three to five walking t rials are needed to obtain reliable regional peak pressure and pressure-tim e integral values when the two-step data-collection protocol is used. Altho ugh either method can be used for pressure data collection, one method shou ld be used consistently when repeated assessments are required.