Renal bone disease: radiological investigation.

The bone disease associated with chronic renal impairment is complex and multifactorial, and has changed over past decades. Whereas originally features of vitamin D deficiency (rickets/osteomalacia) and secondary hyperparathroidism (erosions, osteosclerosis, brown cysts) predominated, improvement in management and therapy have resulted in such readiographic features being present in a minority of patients. Metastatic calcification and "adynamic" bone develop as a complication of disease (phosphate retention) and treatment (phosphate binders). New complications (amyloid deposition, noninfective spondyloarthropathy, osteonecrosis) are now seen complicating long-term hemodialysis and/or renal transplantation. Radiographs remain the most important imaging technique, but occasionally other imaging and quantitative techniques (CT, MRI, bone densitometry) are relevant to diagnosis and management.