Biochemical studies in the evaluation and management of osteoporosis: current status and future prospects.
OBJECTIVE
To examine the current status of biochemical markers of bone remodeling and to offer a perspective on their future clinical applications.


METHODS
We provide a comprehensive overview of the bone remodeling cycle, the hormonal control of bone remodeling, the specific biochemical markers of bone resorption and bone formation, and their current clinical applications.


RESULTS
Bone remodeling occurs in discrete packets, known as bone modeling units, on the surfaces of the skeleton. Osteoclasts are responsible for bone resorption, and osteoblasts are responsible for bone formation. Bone resorption and formation are normally coupled, and an imbalance in these processes can lead to metabolic bone diseases such as osteoporosis. Investigators have attempted to measure various biochemical markers of bone resorption (such as urine calcium and hydroxyproline) and formation (such as bone-specific alkaline phosphatase and osteocalcin) as a reflection of response to therapy. Although several markers of bone resorption and formation can be assayed, an ideal marker has yet to be discovered or proved.


CONCLUSIONS
Until a precise, inexpensive assay is developed, currently available biochemical markers, used in conjunction with measurements of bone density, are considered the most reasonable tools for classifying and directing the management of osteoporosis.
Kleerekoper
M
M
Division of Endocrinology, Department of Internal Medicine, Wayne State University, Detroit, Michigan, USA.
Edelson
G W
GW