The influence of hind-foot bone size and shape on the scaling of joint surface area

Introduction: Despite the wide variation in the size and shape of humans and their feet, less is known about how our feet change shape with increasing size. The square-cube law states that if a bone grows isometrically, the surface area (SA) will grow at a slower rate than the volume (SA = volume^2/3), with either side of this termed allometry. Following isometric scaling, as bone and body mass increase in volume joint contact stress increases more rapidly (stress = force/SA). For example, someone with a talar dome joint surface area (JSA) of 18cm2 and body mass of 75kg will have an estimated pressure of 1.6MPa at heel strike, whereas someone with the same size JSA that weighs 90kg will have an estimated pressure of 1.9MPa, a 20% increase in relative pressure.
Source: Journal of Science and Medicine in Sport - Category: Sports Medicine Authors: Tags: O2023SMA-307 Source Type: research