PTH acts on the bone, kidney and intestine to have a net effect of increasing serum calcium and decreasing serum phosphorous. PTH acts to increase serum calcium by releasing it directly from the bone. This involves removal of bone and replacing it with osteoid tissue, and in more advanced cases osteoid plus fibrous tissue. Other radiographic findings are resorption of subperiosteal bone, best seen along the margins of the phalanges of the hands. In the skull there may be gross trabeculations or a granular appearance resulting from lytic skull lesions.
Fractures can also occur.
Refer to the forearm radiograph again. As noted before, a right radial fracture is noted with generalized severe demineralization, which can occur solely due to rickets or secondary hyperparathyroidism. Metaphyseal fraying and cuffing are noted, consistent with rickets. Multiple lytic lucent lesions within the diaphyses consistent with brown tumors are indicative of secondary hyperparathyroidism. Alagille D. Alagille syndrome today.