The mode of progression of subperiosteal resorption in the hyperparathyroidism of chronic renal failure.

Subperiosteal resorption in finger phalanges is usually thought to be the result of osteoclastic bone resorption on the periosteal surface of bone, progressive centripetally, with creation of the serrated appearances and "lace-like" patterns in periosteal cortical bone. Our longitudinal microradioscopic observations in patients with secondary hyperparathyroidism of chronic renal failure have revealed evidence of another pathogenetic mechanism: by the enlargement of intracortical juxtaperiosteal resorption spaces, the remaining thin layer of bone is broken down from inside the bone, i.e., a centrifugal rather than centripetal process.