Primary Hyperparathyroidism: Changes in Trabecular Bone Remodeling Following Surgical Treatment--evaluated by Histomorphometric Methods

Iliac bone biopsies from 11 patients who underwent successful surgery for primary hyperparathyroidism were examined before and median 7 months after surgical treatment. Trabecular bone volume increased (p less than 0.05) and eroded (p less than 0.005) and osteoid covered surfaces decreased (p less than 0.005) in the postoperative period. Also, a decline in tetracycline labeled surfaces was noticed (p less than 0.02). Osteoid thickness, mineral appositional rate and mineralization lag time were unchanged. Bone formation rate at the level of the basic multicellular unit (BMU) was unaffected, but at the tissue level bone formation rate diminished (p less than 0.02). The surgical cure of primary hyperparathyroidism was found accompanied by a change in bone metabolism as the trabecular bone remodeling decreased from a high turnover to a low turnover state. The spongy bone mass increased after parathyroidectomy but the clinical significance of this finding was not clear.