Endemic fluorosis of the skeleton: radiographic features in 127 patients.

Abstract

A wide range of radiographic appearances have been reported in skeletal fluorosis, but little has been written about the spectrum of radiographic features. We evaluated the spectrum of radiographic appearances in this disorder to help with its diagnosis and differentiation from other metabolic skeletal disorders. One hundred twenty-seven patients with clinically proved endemic fluorosis had radiographs of the chest, spine, pelvis, elbow, forearm, and knee obtained. The radiographic findings were classified as osteosclerosis, osteopenia, intermittent growth lines, diaphyseal widening, or soft-tissue ossification. Two different osteopenic patterns were defined: an osteoporotic pattern with overall decreased bone density and an osteomalacic pattern that combines the features of osteoporosis with bone deformity. Soft-tissue ossification included involvement of ligaments, tendons, and interosseous membranes. Ninety-eight of the patients (89% of the adults) had some evidence of calcification and/or ossification of the attachments of ligaments, tendons, muscles, and interosseous membranes. Osteosclerosis was seen in 54 patients (43%), and osteopenia was seen in 51 patients (40%). Of the patients with osteopenia, the osteoporotic pattern was seen in 28 and the osteomalacic pattern in 23. Growth lines were found in 89 patients (70%). Metaphyseal osteomalacic zones were found in children. Diaphyseal widening was present in 35 patients (28%). Endemic skeletal fluorosis can have a wide variety of radiographic appearances, including calcification and/or ossification of the attachments of soft-tissue structures to bone, osteosclerosis, osteopenia, growth lines, and metaphyseal osteomalacic zones.