Age-related differences in foot structure and mobility

Abstract

Previous research has suggested that changes in foot anthropometrics occur with age, however, these age-related changes remain unclear. The use of portable technology, such as of three-dimensional (3D) body scanners, to collect foot anthropometrics facilitates the exploration of potential differences between and within individuals. Therefore, the purpose of this study was to examine age-related differences in foot anthropometrics using a 3D foot scanner. Sixteen young (8 males, 8 females, mean age 23.6±3.7 years) and sixteen older (8 males, 8 females, mean age 71.6±5.9 years) adults without foot deformities or lower-extremity injuries were recruited. Eight anthropometric measures of each foot were obtained during weight bearing (WB) and non-weight bearing (NWB) conditions using a portable, white light, 3D scanner (TechMed 3D Inc., QC). Measures included dorsal arch height (DAH), foot length (FL), truncated foot length (TFL), forefoot width (FFW), midfoot width (MFW), rearfoot width (RFW), arch height ratio (AHR) and foot mobility magnitude (FMM). Significant differences in foot measures between age groups were analyzed using an independent samples t-test. A secondary comparison between age groups was also evaluated using an analysis of covariance (ANCOVA) with TFL as a covariate. The older group had greater arch height ratio (AHR) during weight bearing (WB) and non-weight bearing (NWB), as well as greater dorsal arch height (DAH) in the NWB condition, suggesting that the older group had a higher arch. Further, the older group had significantly greater rearfoot width (RFW) during WB than the younger group, indicating a greater splay of the metatarsus in the older group. After controlling for the TFL, the older group also showed a greater DAH in the NWB condition. In addition, the forefoot width (FFW), RFW and midfoot width (MFW) in the NWB condition were also significantly greater for the older adults. Furthermore, for the WB condition, the older group had significantly greater DAH and RFW. Additionally, the older group showed less mobility of the foot. Preliminary results based on the sample size of the study provide evidence of anthropometric foot variations between younger and older adults. Examining differences in foot structure and mobility between younger and older adults is fundamental for comprehending foot mechanics and function during movements, such as gait.