Objective: The purpose of this thesis was to determine the degree of difference between anthropometric and heel pad tissue characteristics of the lower extremities of PMHS compared to living populations as well as to establish a wholistic procedure for extensive measurements of the foot using methodology previously used in lower limb anthropometry, x-ray imaging, and ultrasound imaging studies.
Methods: Thirty-seven PMHS were included in the anthropometry analysis, 21 PMHS were included in the x-ray analysis, and 32 PMHS were included in the ultrasound analysis. For the anthropometry, measurements were taken in seated and standing positions and included bimalleolar breadth, heel breadth, navicular height (medial prominence), navicular height (inferior medial border), talar head height, plantar curvature height, lateral malleolar height, medial malleolar height, acropodion foot length, hallux foot length, horizontal foot breadth, ball of foot length, and dorsum height. Comparisons were then made between left and right feet, seated and standing positions, males and females, and PMHS and living populations. For the x-ray analysis, two of the anthropometry measurements, navicular height (inferior medial border) and talar head height, had values for anthropometry compared against measurements determined through x-ray imaging. For the ultrasound analysis, ultrasound images were taken of the plantar foot at the calcaneus at loadings of 0, 5, 10, 15, 20, and 30 Newtons. Thicknesses, stiffnesses, and compressibility indexes were determined using the images, and these values were then compared against values seen in living populations.
Results: Left and right feet were found to have no significant differences in anthropometry. Seated and standing positions were found to be significantly different in 12 of the 13 measurements. Male values were found to be significantly different from female values in both seated and standing positions for all measurements except for plantar curvature height. By determining percent difference values between seated and standing positions for both males and females, no significant difference was found between sexes in their respective measurement changes from seated to standing positions except in plantar curvature height and lateral malleolus height. Eleven of the 13 measurements showed agreement between PMHS and living populations, with talar head height and plantar curvature height showing greater than 10% difference. In the x-ray analysis, navicular height was significantly different between anthropometry and x-ray values, and talar height was not significantly different. In the ultrasound analysis PMHS were found to have thinner and stiffer heel pads with lower compressibility than living populations.
Conclusions: A wholistic procedure for foot measurements and analysis was developed which incorporates methodology from previous literature. For foot measurement, x-ray imaging was shown to be necessary for certain landmarks but not for others. Results from this study have provided quantification of posture and sex differences as well as quantification for differences between PMHS and living populations for foot anthropometry. Differences were also quantified for the thickness, stiffness, and compressibility of PMHS compared to living populations. The results show that PMHS anthropometry sufficiently represents that of living people’s anthropometry when sex and postural differences are accounted for, but PMHS is not representative of living populations regarding heel pad thickness, stiffness, or compressibility, and these differences must be considered in lower extremity testing.