Ossification of the ligamentum flavum: a unique report of a Hispanic woman

Ossification of the ligamentum flavum (OLF) is a disease of ectopic bone formation within the ligamentum flavum, which may result in mass effect and neurological compromise. The low thoracic region is the most common region of occurrence, and this is followed by the cervical, then lumbar, spine. The prevalence of OLF is significantly higher in the Japanese population compared with other nationalities and has a male preponderance. Ossification of the ligamentum flavum has been reported in association with the more common ligamentous pathological entities-ossification of the posterior longitudinal ligament and diffuse idiopathic skeletal hyperostosis. These latter two conditions have been linked to several metabolic processes, and a possible genetic basis has been hypothesized. Here, the authors present a unique case of OLF of the cervical spine in a patient with idiopathic hypercalcemia. (DOI: 10.3171/2011.1.FOCUS10266)