Effects of heel height and shoe shape on the compressive load between foot and base: a graphic analysis of principle

Even in the ever-changing and increasingly technical realm of medicine, common sense approaches are needed. We can still learn from our predecessors by using their practical and simple methods. In this article a graphic approach in the sagittal plane is used to explain the relationship between the heel height of a shoe and load under the foot. By using an elementary theoretical model based on schematic sketches, an analysis of principle can be performed to calculate the change in the distribution of mechanical stress in the planta with change in foot orientation. The model shows that when standing posture remains unaltered, load under the forefoot increases and load under the heel decreases with elevated heel height and the corresponding changes in shoe shape. These results can be confirmed by pedobarographic and gait-analysis measurements, but the graphic method can be used without application of advanced instrumentation. The rationale behind the model is to use common terms and simple means to facilitate a more fundamental understanding of complex mechanical orthopedic problems. The method is meant to be a helpful supplement to clinical judgment in the many situations in which advanced instrumentation is not available.