Studies have shown significant correlations between ulceration and high pressure areas on the foot, however, few studies have quantified plantar pressure patterns for normal walking. There is no normative data nor is there a standardized variable set for describing plantar pressure patterns. The purpose of the study was to quantify in-shoe plantar pressure patterns during walking and provide an initial database and variable set for use in both clinical and research environments.

Thirty males free of lower extremity deformity volunteered as subjects. The FScan Insole System (Tekscan, Boston, MA) was used to collect foot pressure data during walking (100 Hz) simultaneously with ground reaction force (GRF) data (AMTI, 500 Hz) for the purpose of calibration validation. A total of five steps of data per subject was collected. The FScan data were evaluated using a custom foot pressure analysis software package.

One hundred and twenty-five variables were identified and used to develop a database describing normal plantar pressure walking patterns. The GRF results showed no statistical differences between the FScan and force platform (FP) magnitude data, however, the FScan data exhibited a slight temporal shift for the first maximum and minimum forces. Correlation coefficients between corresponding points on the two curves showed lesser values at initial contact and prior to toe-off due primarily to foot sensor orientation relative to the walking surface. The data analysis indicated that plantar pressure patterns could be effectively quantified using the identified variable set but that caution must be exercised due to the strengths and weaknesses associated with different variables. The ratio variables are very sensitive measures but are prone to error. The summation variables are more reliable and comparable to the measures from the FP system. The timing variables provide useful timing pattern information. The variables from the 12-area foot model appear to be valuable clinical tools for diagnosing foot disorders. Continuous measures are recommended since they provide both spatial and temporal information over the entire support phase and are easy to visualize relative to function. Quantification of the variables provided a normal database for future use in the diagnosis and evaluation of foot disorders.