The effect of short-term calcitonin administration on biochemical bone markers in patients with acute immobilization following hip fracture.

The effect of salmon calcitonin on changes in mineral metabolism was studied in 40 elderly patients with recent hip fracture. All patients underwent surgery (internal fixation) 1 week after admission and were randomly divided into two equal groups: group A, which received no treatment, and group B, which received 100 IU/day salmon calcitonin intramuscularly for 2 weeks starting on admission. Blood and 24-h urine parameters of mineral metabolism were measured on admission and at the end of weeks 1 and 2. No intra- or intergroup changes in serum calcium, phosphorus or alkaline phosphatase were observed. At the end of week 2 biochemical markers of bone resorption (urinary calcium and hydroxyproline) had significantly increased in group A and significantly decreased in group B, indicating a reduction in bone resorption in group B. Urinary phosphorus had also increased in group B, possibly due to the phosphaturic effect of calcitonin. It is concluded that immobilization resulting from a hip fracture, and possibly surgery itself, causes significant changes in biochemical markers of bone resorption. Calcitonin successfully reverses these changes and may also be effective in preventing subsequent bone loss, particularly in patients who cannot be remobilized immediately.