Signs and symptoms of
The density of the bone determines the strength of the bone. Osteoporosis is a thinning or weakening of the bones. In primary hyperparathyroidism, the diseased gland makes too much parathyroid hormone (PTH), which in turn causes an increased breakdown of normal bone. As the bone breaks down, the bone density decreases which in turn increases the risk of fractures or broken bones. In extreme cases called "osteitis fibrosa cystic" the bone becomes so soft that it becomes deformed. Osteitis fibrosa cysticaOsteitis fibrosa cystica - An extreme form of bone disease in which the bone become so soft that it deforms. is very rare in developed countries. The density of bone can be measured by a dual-energy x-ray absorptiometry(DEXA) scan. Typically, this test measures bone density at three sites: forearm, spine and hip. The World Health Organization ranks bone density based on the "T-score" which is a measure of how dense a patient's bone is compared to a normal, healthy 30-year-old adult.
- Normal (normal bone mass): T-score between 0 and -1
- Osteopenia (low bone mass): T-score between -1 and -2.5 There is an increased fracture risk but does not meet the criteria for osteoporosis.
- Osteoporosis (very low bone mass): T score less than or equal to -2.5 Patients with osteoporosis are in the highest risk category for fractures.
Studies show that after successful parathyroid surgery the bone density will improve by as much as 8 to 12% and the risk of fracture will decrease. 1