Bone modeling and remodeling Bone modeling n Child

Bone modeling and remodeling Bone modeling n Child and adolescent n Non-coupling : bone formation and resorption occur on separate surfaces Bone remodeling n The replacement of old bone tissue by new bone tissue in the adult skeleton n Coupling

Osteoporosis imbalance in bone remodeling Results in thinning and eventual loss of trabecular connectivity

Definition of Osteoporosis is defined as a skeletal disorder characterized by compromised bone strength predisposing a person to an increased risk of fracture. Bone strength primarily reflects the integration of bone density and bone quality. NIH Consensus Conference Normal bone Osteoporosis NIH Consensus Development Panel on Osteoporosis. JAMA 285: 785 -95, 2001

Osteoporosis n Primary osteoporosis n n Older persons and women past menopause in which bone loss is accelerated over that predicted for age and sex. Secondary osteoporosis n Metabolic bone disease n n n Primary prevention n comprehensive measures against other lifestyle-related diseases n Secondary prevention n hyperparathyroidism multiple myeloma or metastatic carcinoma n Malnutrition n Drug therapy n with corticosteroids n Prolonged immobilization n Weightlessness with space travel Should target people at higher risk of osteoporotic fractures Neoplasia n Should provided all the people as n Tertiary prevention n Should be provided the patients and at frail elderly people using medical or long-term care insurance Osteoporosis Tutorial

Factors affecting bone metabolism

Medical treatment for osteoporosis Anti-resorptive agent n Estrogen n SERM Raloxifene (Evista) n Calcitonin n Bisphonate Alendronate (Fosamax) Risedronate (Actonel) Ibandronate (Bonviva) Anabolic agent n PTH (cyclic use) ( Bone formation) n Strontium ranelate ( Bone formation) ( Bone resorption)

Protos OPG

NEJM 2004; 350: 459 -468

AEs of strontium ranelate (Protos) PROTOS Placebo p Gastritis 3. 6 5. 5 0. 066 Gastric ulcer 1. 0 1. 1 NS Esophagitis 0. 8 0. 6 NS Diarrhea 6. 1 3. 6 0. 019 Symptoms (%) • 2 g of strontuim ranelate mix with a glass of water and drink immediately. • Taken before bedtime or 2 -h before/after the meals 16