Primary bone retention in a young adult male with limb disuse: a bioarchaeological case study

Bone mineral and mass are low in limb bones that experience prolonged lack of, or minimal, mechanical stimulation. Cases of ancient human limb paralysis offering an opportunity to examine histological markers of cortical bone modelling and remodelling are rare. To improve our understanding of the spectrum of bone tissue response to its muscular disuse environment in archaeological contexts, we tested whether bone histology in an individual afflicted with long-term loss of muscle function showed unremodelled primary bone due to minimal/absent, mechanical stimulation. We examined cortical bone histology in a 1906–1523 cal BC atrophied post-cranium of a young adult (mid-20s) male who had suffered from Klippel-Feil Syndrome Type III, experiencing minimally paraplegia and potentially complete or intermittent quadriplegia in late childhood/early adolescence. Samples taken from the humeral and femoral midshaft displayed thin cortices and extensive retention of primary bone with only localised Haversian tissue or isolated secondary osteons. The retention of widespread primary bone and thin cortices in this adult individual is evidence for stunted modelling and remodelling due to immobility during early ontogeny. Our bone histology descriptions should be of interest to palaeobiologists investigating the effects of physical inactivity on bone microstructure in fossilised and archaeological human remains.