Frequency and patterns of costovertebral osteoarthritis in two Medieval English populations

Osteoarthritis is one of the most frequently identified lesions in palaeopathological research. It has been extensively studied by both bioarchaeologists and medical researchers for decades, yet the aetiology of osteoarthritis remains unclear. One of the most important aspects of osteoarthritic studies is identifying the distribution patterns of the condition throughout the skeleton. Despite many studies reporting the occurrence of postcranial osteoarthritis, including in the spine, the costovertebral articulations have received little focus. The current study describes the occurrence of costovertebral osteoarthritis in two Medieval English populations from Chichester and Hereford. The presence of eburnation on the joint surfaces was used to indicate osteoarthritis. It was found that osteoarthritis of these joints had a similar frequency in both populations. An interesting pattern also emerged, with the joints of the costo-transverse articulations showing more eburnation than the costovertebral articulations with the vertebral body, except in the first rib. The pattern of distribution identified throughout the spine may provide insight into possible aetiological factors leading to the development of costovertebral osteoarthritis.