Diagnosis of Metabolic, Endocrine, and Congenital Bone Disease

Although metabolic bone diseases are common, they may be difficult to diagnose on the basis of clinical and radiological findings. Understanding their diverse manifestations using different imaging studies allows early and specific diagnosis. Generally, in the early stages of the disease, bone scintigraphy shows generalized increased uptake. As the disease progresses, bone scintigraphy has well-recognized features, such as focal and generalized increased uptake in the long bones, axial skeleton, and periarticular areas. Generalized uptake of the skull, mandible, and sternum is another pattern. Finally, focal uptake in the costochondral junctions, soft tissue calcification, and faint, or absent, kidney uptake are additional features. Knowledge of these different scintigraphic patterns helps obtain the highest diagnostic value. Important practical applications of bone scan in metabolic bone disease are the detection of focal conditions or focal complications of such generalized disease such as the detection of fractures in osteoporosis and pseudo fractures in osteomalacia and the evaluation of Paget’s disease, particularly disease activity. Specific conditions show different scintigraphic features, sometimes specific and diagnostic, and are presented.