A test of the New Coimbra method of recording entheseal changes as applied to the foot skeleton

Prior studies have indicated that entheseal changes throughout the skeleton are largely reflective of age and body mass with mixed results concerning activity patterns. To add to this debate, this study tests the effectiveness of employing the New Coimbra method to record entheseal changes of the calcaneus (Calcaneal tendon enthesis), hallucal metatarsal (Peroneus longus m. tendon, and Tibialis anterior m. tendon entheses), and fifth metatarsal (Peroneus brevis m. tendon enthesis) to understand past activity patterns. Presence and severity of entheseal changes were scored for 71 white adults from the William M. Bass Donated Skeletal Collection, and these scores were contrasted according to age, sex, stature, body mass (BMI), and occupation. Spearman's rank correlations show that age has the greatest impact on changes for the Calcaneal tendon enthesis, the Peroneus brevis m. tendon enthesis, and the Tibialis anterior m. tendon enthesis. For all of these entheses, entheseal scores increase as age increases. Stature is the largest contributing factor to changes in the Peroneus longus m. tendon enthesis, and this relationship is negative: entheseal scores decrease as stature increases. BMI has a limited effect on entheseal changes in the foot skeleton, and this relationship may instead be mediated by gait differences related to stature. No statistically significant relationships between entheseal changes and occupational standing ranks were found, although this may be related to the ways in which occupations were recorded and ranked. It is possible that statistically significant effects of physical activity patterns on the expression of entheseal changes could be documented using other measurements of activity patterns beyond occupational standing. These findings support prior studies that established age as a major contributor to entheseal changes but show that stature also contributes to enthesis formation in the foot.