A Qualitative and Quantitative Analysis of the Developing Distal Tibia and Talus

Understanding the factors which influence healthy bone development may inform geriatric clinical interventions, in addition to treating and analysing paediatric trauma and pathology. The overall project aim was to investigate ontogenetic changes in the trabecular structure of the juvenile distal tibia and talus, which both have important weight-bearing roles within the talocrural joint during locomotion. The project aimed to address three research objectives. Research Objective 1 aimed to identify general ontogenetic trabecular patterns within the distal tibia and talus. Research Objective 2 aimed to examine the internal structural heterogeneity of the distal tibia and talus during development. Finally, Research Objective 3 aimed to compare the trabecular architecture of the distal tibia and talus throughout development. Despite the relationship between the distal tibia and talus within the ankle joint, the juvenile trabecular architecture of these bones has not been studied in conjunction with each other. Comparing two anatomically different bones that share similar locomotive demands may provide insight into how developmental and biomechanical influences interact to result in adult intra-skeletal and inter-skeletal variation. These research objectives were pursued through a qualitative radiography study, followed by a qualitative and quantitative microcomputed tomography (μCT) study on distal tibiae and tali from the Scheuer Juvenile Collection. Overall, the results of the radiographic and the microcomputed tomography studies agreed with each other. Early trabecular development appears to be genetically driven, dictated by the progression of endochondral ossification and presence of vasculature. Before 1 year of age, the distal tibia and talus undergo constructive regression, as adaptation to biomechanical influences begins. After 1 year of age, structural heterogeneity of the skeleton increases as the trabecular architecture of these bones becomes increasingly adapted to their local functional requirements as gait matures. After 8 years of age, changes in the internal structure of the talus appear to be driven by growth resulting in increased body weight forces. This project therefore explores the trabecular development of the distal tibia and talus, providing insight into the factors that drive healthy bone development, which in turn may be useful in the treatment and analysis of paediatric trauma and pathology.