Radiographic cervical spine osteoarthritis progression rates: a longitudinal assessment.

Relative to other sites, the cervical spine has received little attention in the osteoarthritis (OA) literature. Using data from a longitudinal study, we provide age-specific progression rates of radiographic cervical spine OA, by gender. Data from cohort subjects (ages 40+) from the Clearwater Osteoarthritis Study were analyzed (N = 707). All study subjects' demonstrated radiographic cervical spine OA at baseline (2+). Lateral cervical spine radiographs were taken biennially. The study outcome was radiographic disease progression. A grade increase of 1, or more, by the Lawrence and Kellgren ordinal scale was considered progression. Incidence rates were calculated as per 100 person-years of observation. We show that the progression rates for cervical spine OA increase with age. For all ages combined, men demonstrated higher rates of progression compared with women. However, among subjects in their forties and fifties, women were more likely to experience worsening of their disease when compared with men. Progression rates were similar for men and women in their sixties (8.2 and 8.0, respectively). Among subjects in their seventies, men demonstrated a significantly higher rate of progression compared with women (12.5 and 8.6, respectively). As the baby-boomer population continues to increase, cervical spine OA progression assessment can be a useful tool for health-care resource planning. Cervical spine OA research offers an abundance of opportunities. Instability as a precursor to the development of cervical spine OA warrants further research. Epidemiological studies addressing demographic differences (e.g., gender, age) in the incidence of cervical spine OA will contribute to the current knowledge base.