Snapshot A 67-year-old woman presents to the emergency department after falling while walking down the stairs of her home. She landed on her rear on a carpeted floor and denies hitting her head. She experienced severe pain in her right hip after the fall and is unable to bear weight on the affected side. Menopause began 17 years ago. She has smoked 1-pack of cigarettes for the past 40 years. On physical exam, her right leg is shortened, adducted, and externally rotated. Laboratory testing is unremarkable. Introduction Clinical definition decreased bone mass (osteopenia) that significantly increases the patient's risk of fracture Epidemiology Incidence most common types of osteoporosis are post-menopausal senile Risk factors post-menopausal women being ≥ 65 years of age people of Caucasian and Asian descent lifestyle factors such as poor physical activity vitamin D deficiency and poor calcium intake smoking alcohol use disorder medications such as warfarin, lithium, proton pump inhibitors, and glucocorticoids hyperparathyroidism hyperthyroidism multiple myeloma malabsorption syndromes Etiology Pathogenesis in young adulthood, peak bone mass is achieved and this is determined by a number of factors (e.g., genetics) after this peak bone mass is attained, there is a small decrease in bone formation with every cycle of bone remodeling senile osteoporosis osteoblasts have their biosynthetic and proliferative ability reduced with age poor physical activity mechanical force on bone stimulates bone remodeling athletes have increased bone density decreased physical activity results in bone loss decreased estrogen levels such as in menopause, decreased estrogen levels increase bone resportion and formation however, the rate of formation is less than resorption resulting in a net bone loss increased osteoclast activity is significant in areas of bone with large surface area such as the vertebral bodies, leading to vertebral compression fractures there is trabecular and cortical bone loss Presentation Symptoms fractures (e.g., vertberal and hip), otherwise, patients are typically asymptomatic Physical exam may see loss in height Imaging DEXA indication all women ≥ 65 and all men ≥ 70 years of age smoking and sedentary lifestyles are risk factors notes T-score ≤ -2.5 Studies Labs serum calcium, phosphorus, parathyroid hormone, and alkaline phosphatase are normal Histology histologically normal; however, there is a decreased quantity of normal bone Differential Laboratory Abnormalities in Select Bone DisordersEtiologySerum PhosphateSerum CalciumSerum Alkaline PhosphataseParathyroid HormoneOsteomalacia / ricketsDecreasedDecreasedIncreasedIncreasedOsteoporosisNormalNormalNormalNormalOsteopetrosisNormalNormal or decreasedNormalNormalPaget disease of the boneNormalNormalElevatedNormalOsteitis fibrosa cysticaPrimary•hyperparathyroidism- decreasedSecondary•hyperparathyroidismincreasedPrimary•hyperparathyroidismincreasedSecondary•hyperparathyroidismdecreasedPrimary and secondary hyperparathyroidism increasedPrimary and secondary hyperparathyroidism increasedHypervitaminosis DIncreasedIncreasedNormalDecreased Treatment Conservative calcium and vitamin D supplementation strength training smoking cessation Medical bisphosphonates indication first-line for pharmacologic therapy in osteoporosis raloxifene second line therapy for osteoporosis can cause hot flashes and venous thromboembolism does not cause endometrial hyperplasia or increase risk of breast cancer teriparatide indication considered first-line in patients with a very high risk of fracture Complications Fractures Prognosis Generally good if detected early and appropriately managed