[Comparative study of serum osteocalcin and of the histomorphometric evaluation of iliac biopsy in postmenopausal osteoporosis].

The histological examination of iliac biopsies in patients with osteoporosis shows varying stages of remodeling which cannot be detected by the usual laboratory tests. We measured the serum osteocalcin level, a new test, specific for bone, in 26 postmenopausal women with primary osteoporosis. The results were correlated to the findings of the iliac biopsy. Osteocalcin is significantly related to all the parameters of bone formation but not with bone resorption. When patients were divided into 3 groups, depending on the stage of remodeling from the biopsy, osteocalcin was significantly increased in the group with a high level of bone formation, and lowest in the group with decreased osteoblastic activity than in the group with normal remodeling. Neither the serum alkaline phosphatase nor the measurement of urinary hydroxyproline could distinguish between these group.