On the differential diagnosis of vertebral ankyloses in paleoanthropological material: an example of the Early Iron Age case from the Lower Kama region

Abstract

Differentiating various pathological conditions involving the spine, particularly those leading to vertebral anky-losis, is a challenging task both in paleopathology and clinical practice. The Introduction summarizes cases of ankylosing spondylitis (Bekhterev’s disease) and diffuse idiopathic skeletal hyperostosis (Forestier disease) from the territory of former USSR. In this regard, it is important to mention that, having different etiologies, DISH and seronegative spondyloarthropathies have different reconstructive potential. It is assumed that the increase in DISH prevalence may be associated with an increase in life expectancy and characteristics of the group’s nutri-tional status, while spondyloarthropathies – with endogamy, increased population density due to sedentary life-style and the intensification of agriculture. It is noted that differential diagnostic procedure has been reported only in few Russian-language publications that deal with the topic. This often leads to the statement of not quite justi-fied paleopathological diagnoses. This paper presents results of paleopathological study of a 25–40-year-old male skeleton from burial 183 of the Novo-Sasykul cemetery, dated to the 1st–2nd centuries AD. The site is located in the Lower Kama River region (Bakalinsky District, Republic of Bashkortostan) and attributed to the Pyany Bor Culture. The study is focused on differentiating pathological conditions that lead to vertebral ankylosis on skeletal remains. Principal pathological changes, recorded on the skeleton from burial 183 of the Novo-Sasykul cemetery, were: 1) ankylosis of five consecutive thoracic vertebrae (T7–11) with right-sided ossification of the anterior longi-tudinal ligament and 2) bilateral fusion of the sacroiliac joints. Possible diagnoses include seronegative spondy-loarthropathies (ankylosing spondylitis, reactive and psoriatic arthritis), diffuse idiopathic skeletal hyperostosis (DISH), rheumatoid arthritis, and degenerative changes (osteoarthritis). The differential diagnosis based on mac-roscopic (morphological) indicators allows suggesting a diagnosis of DISH, possibly associated with a spondy-loarthropathy and minor degenerative changes in the spine. Ankylosing spondylitis is certainly excluded from the spectrum of probable spondyloarthropathies. It is noted, however, that specific diagnosis requires an X-ray exa-mination. As a guideline for the specialists, the need for careful differentiation between different pathological con-ditions leading to ankylosis of vertebral segments is emphasized. The latter is important, since reporting ill-considered diagnosis may severely complicate the use of the published data in bioarchaeological reconstructions.