Prevalence and characteristics of osseous bridging between vertebral bodies in the cervical spine: A skeletal study

Osseous bridging (OB) in three or more segments of motions (SOMs) of the mobile spine was initially defined as diffuse idiopathic skeletal hyperostosis (DISH), located particularly in the thoracic spine (T-spine). This pathological phenomenon is often characterized by calcification and ossification, which take place simultaneously or separately. The soft tissues, mainly ligaments and entheses, are calcified, with bone formation not originating from the anterior longitudinal ligament (ALL). DISH formation can involve osteophytes, which are created by the ossification process and can involve soft tissue such as the ALL. The ALL can also be calcified. Until recently, the prevalence of DISH in the general population was considered low (0%–5%) and rare in the cervical spine (C-spine). In a cross-sectional observational skeletal study, we investigated the prevalence and location of C-spine OB between vertebral bodies with fewer than three SOMs. We tested a large sample (n = 2779) of C-spines housed in the Cleveland Museum of Natural History (Ohio, USA). The human sources of the samples had died between the years 1912 and 1938 and represented both sexes and two different ethnic groups: Black Americans and White Americans. The process development can be seen on the ALLs as calcification, osteophytosis, and candle-shaped. Among all of the specimens, 139 (5%) were affected by OB, mostly in one SOM. Prevalence tended to be higher in women, White Americans, and the older age group. The levels most affected were C3–C4, followed by C2–C3 and subsequently, C5–C6. OB involving two consecutive SOMs was found only at C5–C7. We believe it is important to respond to the presence of a single SOM with a presumptive diagnosis of OB and to follow up, identify whether the diagnosis is correct, and take preventive action if possible. There is a need for updated diagnostic criteria and research approaches that reflect contemporary lifestyle factors and their impact on spine health.