A weight bearing method for determining forefoot posting for orthotic fabrication

Orthotic prescription for forefoot posting is commonly based upon measures of the forefoot performed on a non-weightbearing foot. However, the relationship of measures of the unloaded foot to determine orthotic prescription for compensatory forefoot function during gait is still in question. Another approach to determine orthotic prescription is to measure the height of forefoot posting necessary to prevent excessive pronation of the subtalar joint during weightbearing. Therefore, the purpose of this study was to determine the intrarater, interrater and day-to-day reliability of forefoot measures during an active, weightbearing movement. Thirty-two volunteers, 18 females (mean age 38.9 +/- 15.3 yr) and 18 males (mean age 44.8 +/- 20.6 yr) participated in the study. Four examiners performed repeated forefoot measures on both feet using the weightbearing technique during two test sessions separated by a week. Intrarater and interrater reliability (ICC (3,1)) ranged from 0.90 to 0.95 and 0.87 to 0.94, respectively. Day-to-day reliability (ICC (1,1)) ranged from 0.84 to 0.88 for all measures. We conclude that the weightbearing method used in this study to determine forefoot posting is reliable. The acceptable reliability of this method justifies the need for future investigations of the validity and the clinical efficacy of this technique for orthotic prescription.