Non-functional BMA machine.

• Collection of epidemiological data
• Biological assessment as part of routine care.
• Measurement of the Hurst coefficient at D0
• Measurement of bone density and TBS on D0
• Zoledronic acid infusion the month following inclusion
• phone call at 1 month (observance of zoledronic acid)
• Measurement of bone density, calculation of the Hurst coefficient at M12

Inclusion Criteria:

• Women < 85 years old
• Postmenopausal women (amenorrhea for more than 12 months), a confirmation diagnosis should be obtained (amenorrhea for at least 12 months before the inclusion visit).
• Post-menopausal osteoporosis with one or more severe fractures (upper end of the humerus, femur, or tibia; 3 adjacent ribs; lower end of the femur; thoracic or lumbar spine; pelvis), or T score <-3 which justifies setting up a bisphosphonate treatment
• Affiliated to social security

Exclusion Criteria:

• Contraindication to zoledronic acid (allergy to the product, creatinine clearance <35 ml / min, hypocalcemia, open and unhealed lesions of the soft tissues of the mouth)
• Hormone replacement therapy taken in the last 12 months
• Osteoprotective treatment (bisphosphonates, teriparatide, raloxifene, strontium ralenate or denosumab) taken in the last 12 months
• Secondary osteoporosis: hyperthyroidism, hyperparathyroidism, long-term corticosteroid therapy, hypercorticism, hypogonadism, treatment with anti aromatases / LHRH analogues, neoplastic pathology (solid or hemopathy)
• History of bilateral wrist or femur fracture
• Person deprived of liberty by an administrative or judicial decision or person placed under the protection of justice / guardianship or curatorship
• Patient participating in another trial / having participated in another trial within 6 months