Cortical bone loss in a sample of human skeletons from the Muge Shell middens

The Muge shell middens of Cabeco da Arruda, Cabeco da Amoreira and Moita do Sebastiao (central Portugal) have been key sites of archaeological research for 150 years, possibly working as residential sites occupied by semi-sedentary communities during the final Mesolithic. The purposes of this article include the biocultural assessment of metacarpal cortical bone fragility and its associations with age at death, sex and osteoporotic fractures in the Portuguese Mesolithic, as well as a diachronic comparison of cortical bone health in Mesolithic (N = 34) and modern reference (N = 219) samples. Cortical bone at the Muge shell middens displays age and sex-specific trajectories of periosteal apposition and endosteal bone loss, most likely associated with hormonal and behavioural/cultural influences. Metacarpal endocortical bone loss seems to increase with age at death in females, with a simultaneous expansion of the diaphysis. The overall pattern of cortical bone health is similar to the pattern observed in a reference skeletal collection, but elderly women from Muge seem to lose less cortical bone than late twentieth century counterparts from Coimbra. Two older males exhibited vertebral compression fractures, but only one is possibly related with bone fragility.