[Evaluation of diagnostic criteria for hyperostotic diseases on a series of skeletons. Epidemiological implications]

Three sets of diagnostic criteria for diffuse idiopathic skeletal hyperostosis were evaluated in 78 medieval skeletons from subjects aged 30 years or more at the time of death. Prevalence of the disease ranged from 7.6 to 11.5% according to the criteria used. Gross examination of skeletons was consistent with hyperostosis in 16.6% of cases. The lesions observed are described. A new set of criteria is suggested: 1) involvement of three vertebras (bridging of two intervertebral spaces) at the lower thoracic spine; 2) involvement of four vertebras (bridging of three intervertebral spaces) at any level; 3) flowing ossification along the anterolateral aspect of at least two contiguous vertebras; 4) enthesopathies without remodeling of the cortex symmetrically involving the posterior calcanei, olecranons, and upper patellas. Decreased disk height in elderly subjects and para-articular bony bridging of the sacroiliac joints do not rule out the diagnosis. The diagnosis is definite in patients with criteria 1 or 2, probable in patients with criteria 3 and 4, and possible in patients with criterion 3 or criterion 4.