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Notes: Abstract Local immobilization is a good model for studying disuse-induced bone loss and to appreciate the effects of drugs, especially preventive action of antiresorptive therapy. In fact, increased osteoclastic activity is the main point of such a bone loss. The effect of salmon calcitonin was investigated on immobilization-induced osteoporosis in the sheep. Twenty-four nonovariectomized, adult, female, Welsh mountain sheep were submitted, by an external fixator procedure, to hock joint immobilization from the tibia to the the metatarsus for 12 weeks. The sheep were randomized into two groups receiving either an injection of placebo or salmon calcitonin (100 IU) three times per week, for 12 weeks. Histomorphometric analysis was performed on pre-and posttherapeutic transiliac bone biopsies, and on immobilized (left) and nonimmobilized calcanei removed after sacrifice. Results showed a 29% significant decrease of cancellous bone volume in the placebo group due to a significant reduced trabecular thickness when we compared immobilized versus nonimmobilized calcaneus. This structural adaptation appeared to be the consequence of an overall increased bone turnover. In the calcitonin group, same changes were observed, with a 23% reduction of bone mass in the immobilized calcaneus. By comparing calcitonin with placebo groups in both left and right calcanei, no difference was found. On the other hand, a significant increase of mineralization parameters in the iliac crest was only observed in the calcitonin group. In conclusion, salmon calcitonin, at a dose of 100 IU/day three times a week, was ineffective in preventing local disuse osteoporosis in this sheep model.

Notes: Abstract. The aim of this study was to evaluate the effect of intermittent calcitonin on femoral bone quality in adult ewes from the time of ovariectomy. Six months after the start of the experiment, bone density measurements and mechanical testing (torsion and resonant frequency analysis of the diaphysis and compression of an excised trabecular bone cylinder from the femoral neck) were performed in sham-control and ovariectomized (OVX) ewes treated with placebo or salmon calcitonin (50 or 100 units, 3 times/week). Crystallinity of bone was evaluated by measuring X-ray diffraction line broadening. After OVX, a nonsignificant bone loss was found at all measured sites in the femur (−3 to −9%) together with a decreased biomechanical competence in the trabecular bone (compressive strain −28%, P 〈 0.05). Treatment with salmon calcitonin, 50 or 100 IU subcutaneously three times a week from the time of ovariectomy, resulted in a significant dose-dependent preservation of bone strength in the trabecular bone of the femoral neck compared with OVX. No adverse effects of calcitonin were observed on bone crystal composition as assessed by diffractiometry. We conclude that in adult ewes intermittent calcitonin treatment from the time of OVX was associated with a significant preservation of cancellous bone strength and strain in trabecular bone of the femoral neck, without affecting crystalline properties of bone.

Notes: Abstract: Vertebral fractures may be minor or lead to pain, decreased physical function, immobility, social isolation and depression, which together contribute to quality of life. A Working Party of the European Foundation for Osteoporosis has developed a specfic questionnaire for patients with vertebral fractures. This questionnaire, QUALEFFO, includes questions in the domains pain, physical function, social function, general health perception and mental function. QUALEFFO was validated in a multicenter study in seven countries. The study was done in 159 patients aged 55–80 years with clinical osteoporosis, i.e., back pain and other complaints with at least one vertebral fracture and lumbar bone mineral density T-score 〈−1. Patients with a recent vertebral fracture were excluded because of unstable disease. Controls were age- and sex-matched, and did not have chronic back pain or vertebral fractures. Subjects with conditions exerting a major influence on quality of life were excluded. The QUALEFFO was administered twice within 4 weeks and compared with a generic questionnaire, the Short Form 36 of the Medical Outcomes Study (SF-36). Standard spinal radiographs were made for assessment of vertebral height. Seven questions were removed from the analysis because of low response rate, linguistic ambiguities or redundancy. The 41 remaining questions were analyzed for repeatability, internal consistency and the capacity to discriminate between patients with vertebral fractures and controls. Comparison with the SF-36 was performed within similar domains by conditional logistic regression and by receiver operating characteristic (ROC) curves. The repeatability of QUALEFFO was good (kappa statistics 0.54–0.90) and 26 of 41 questions had a kappa score ≥0.70. The internal consistency of the five domains was adequate, with Crohnbach α around 0.80. All except five questions discriminated significantly between patients and controls. The median scores of QUALEFFO were significantly higher in patients with vertebral fractures than in controls in all five domain (p〈0.001), which is consistent with decreased quality of life in patients with osteoporosis. Spinal radiographs were assessed using the McCloskey–Kanis algorithm. According to this, 124 patients (78%) had vertebral fractures of ≥3 SD severity, in contrast with 7 controls (4%). Significant correlations existed between scores of similar domains of QUALEFFO and the SF-36, especially for pain, physical function and mental function. All five domains within each questionnaire discriminated significantly between fracture cases and controls. The odds ratios for pain and social function were greater for QUALEFFO, while general health perception was more discriminating using the SF-36. The ROC curve analysis of QUALEFFO indicated that all five domains were significantly predictive of vertebral fractures. When comparing similar domains of the two questionnaires, QUALEFFO domains demonstrated significantly better performance for pain, physical function and social function. The QUALEFFO total score and SF-36 physical composite score showed similar performance. In conclusion, QUALEFFO is repeatable, coherent and discriminates well between patients with vertebral fractures and control subjects. The results of this study confirm the decreased quality of life in patients with vertebral fractures.

Notes: Abstract The morbidity of osteoporosis is caused by fractures. Vertebral fractures lead to pain and disability and a decrease in quality of life. A Working Party of the European Foundation for Osteoporosis has developed a specific questionnaire for patients with established vertebral osteoporosis. This questionnaire is intended for use in clinical trials. The questionnaire consists of questions and visual analogue scales in the following domains: pain, activities of daily living, jobs around the house, mobility, leisure and social activities, general health perception and mood. The questionnaire has been translated from English into French, German, Italian, Hebrew, Swedish and Dutch. The questionnaire is currently being validated in a multicentre study involving patients with stable osteoporosis and control subjects. Preliminary results indicate that the reproducibility is sufficient and that the questionnaire is able to discriminate between patients with vertebral osteoporosis and control subjects.