Width of clavicular cortex in osteoporosis.

Thinning of the upper cortex of the clavicle, measured on a standard chest radiograph, may help in the diagnosis of osteoporosis. No precise level at which osteoporosis occurs can be given, but a reading of 1.5 mm. or under is indicative of osteoporosis, while a smaller incidence is associated with readings of 2 mm. and above. There is significant correlation between thinning of the clavicular cortex and other radiological indications of osteoporosis. Thinning may occasionally point to unsuspected bone disease, in osteomalacia as well as in osteoporosis. As chest radiographs are taken in a high proportion of both outpatients and inpatients, the method has a wide applicability.