AbstractThe trajectory of the paediatric foot size and shape is poorly understood despite existing data. Furthermore, the two-dimensional (2D) foot anthropometrics typically captured using manual methods tell us very little about the multiplanar three-dimensional (3D) morphology of the foot. Finally, although 3D scanning allows for a quick, accurate and high resolution foot assessment, most paediatric foot studies to date use 2D methods.Therefore, this thesis aims to (1) investigate the reliability of a novel hand-held 3D scanning method to assess static paediatric foot shape, (2) establish 3D variables to evaluate foot surface morphology and (3) describe the development of children’s 2D foot anthropometry and 3D surface morphology between the ages of 2 and 7 years. In the pilot study good reliability of hand-held 3D scanning of the paediatric foot was demonstrated in bipedal stance from the age of 3 years. The ability of curvedness and shape-index to evaluate surface morphology was also established, highlighting their capability to describe novel aspects of foot surface morphology development. In the main study, 148 children were recruited to participate for 3D hand-held scanning in bipedal stance. Thirteen 2D measures in three foot regions (rear-, mid- and fore-foot) were analysed using one-way ANOVA, and post-hoc multiple comparisons, to explore differences in foot size and proportions among the age-groups of 3, 4, 5, 6 and 7 years. Curvedness and shape-index were also investigated among the same age-groups, to explore differences in 3D surface morphology using statistical parametric mapping. Finally, simple linear regression was used to explore if age or normalized 2D measures can predict the 3D surface morphology changes identified. The key foot anthropometric findings revealed, for the first time, that foot regions have distinct developmental trajectories, indicating that the rear-foot grows differently compared to the mid- and fore-foot in height, width, and proportions. These results imply that the development of foot shape and size should not be described based on a few selected measures, instead, a comprehensive characterization of all three regions should be considered. The analysis of 3D foot surface morphology demonstrated (1) an increase in local 3D slenderness, (2) increasing prominence of anatomical landmarks, (3) a reduction in rear-foot eversion and (4) a novel trajectory in the development of the medial longitudinal arch (MLA). Most differences occurred between the ages of 4 and 6 years, with a distal to proximal development of the MLA until the age of 5 years, after which it was proximal to distal. The simple linear regressions of normalized 2D measures with 3D shape-descriptors showed that in the absence of 3D scanning technology, normalized rearfoot height, normalized mid- and fore-foot width can predict aspects of 3D foot surface morphology development. This analysis, for the first time, has also revealed that the changes of rear-foot and MLA surface morphology are less dependent on age, but can be predicted using normalized 2D anthropometric foot measures such as normalized rear-foot
height, normalized mid- and fore-foot width.
This thesis presents a novel protocol and a comprehensive dataset for a higher resolution understanding of paediatric foot anthropometry and 3D surface morphology. These contributions will help inform approaches to research, footwear design, clinical assessment, and monitoring the impact of surgical and non-surgical interventions
|Date of Award||May 2021|
|Supervisor||Stewart Morrison (Supervisor) & Carina Price (Supervisor)|