Radiographic manifestations of experimental aluminum toxicity in growing bone

To evaluate the effect of aluminum on growing bone in the presence of normal renal function, the following experiment was performed. Eight littermate pair-fed pigs (5 weeks old) were randomly assigned to one of two study groups: control C, n = 4, or aluminum treated Al, n = 4. Daily intravenous injections of either aluminum 1.5 mg/kg/day (Al group) or vehicle only (C group) were given during the 8-week duration of the study. The radiographic findings which appeared in the aluminum-treated group and not in the controls consisted of areas of sclerosis in the submetaphyseal regions and the periphery of epiphyses. In addition there was separation of the anterior tibial tubercle. The growth plates did not increase in width despite the presence of osteomalacia and histologic evidence of extensive deposition of aluminum in bone. The area of sclerosis visualized in the radiographs correlated histologically with thickened bony trabeculae. The increased width of these trabeculae is attributable to an increase in primary spongiosum and broadened seams of osteoid.