It is a formidable task to condense into a single presentation what is now approaching 20 years of personal investigation into uremic osteodystrophy. The attempt will be made by concentrating discussion on those aspects of azotemic osteodystrophy that have been established by actual measurement, and by avoiding, so far as is possible, inferences based purely on clinical impressions.
It was first necessary to discard the false dogma that renal rickets is "not rickets at all but renal osteitis fibrosa."1 Systematic osteopathological surveys, using technics adequate for the demonstration of osteoid tissue,2 have proved that defective mineralization of lamellar bone and of the growth cartilage is extremely common in chronic renal failure.3-10 Bony changes of this type may develop in patients with less advanced renal impairment11-13 and, in Europe at any rate, they are commonly recognized as clinically overt rickets (Fig 1) or osteomalacia.8,9,11-16 As a