Osteoporosis. 3rd year mbbs course.pptx

Ppt by 3rd year mbbs student

1. Osteoporosis

2. What is osteoporosis ? A disease characterized by low bone mass and detoriation of bone tissue, leading to enhanced bone fragility and consequent increase in fracture risk Mostly affects women who have crossed the age of 50 and also few men Most common sites of osteoporosis related fractures are :Colles fracture ,spine ( vertebral fractures ), humerus and hip Out of all hip fractures are the most dangerous ones

3. Pathophysiology In osteoporosis, there is increased loss of bone mass, despite normal mineralization Mainly it develops due to an imbalance in bone remodeling, it can be due to increased breakdown of bone (absorption of bone ) by osteoclasts or decreased formation due to osteoblasts Many factors affect it : -Mainly genetic factors (80%)variation in bone density -environmental factors such as exercise and calcium intake during growth -postmenopausal bone loss due to decreased estrogen secretion -Smoking can have a detrimental affect on bone mass density -heavy alcohol intake also is an increased risk factor

4. Types of osteoporosis Idiopathic type : osteoporosis in patients who have no underlying issue Mainly due to age related osteoporosis , or inheritance of genetic variant Secondary osteoporosis :can occur due to variety of diseases and drug treatments In men it can be seen due to hypogonadism or use of glucocorticoids Or various other diseases Glucocorticoid induced osteoporosis : usually seen in patients with systemic inflammatory diseases and chronic pulmonary diseases Depends on the dose and duration of glucocorticoid therapy They mainly reduced bone density by inhibiting the formation of osteoblasts and osteocytes Pregnancy induced osteoporosis : rare form and usually seen in second and third trimester Presents as back pain and multiple vertebral fractures

5. Graph showing bone density with age

6. Clinical features The clinical signs of fracture are pain, tenderness and deformities Fragility Fracture – Low trauma fracture, occur in trabecular bone. The most common sites are : Spine – sudden severe back pain that radiates around the front suggesting vertebral crush fracture. Hip – Fracture of proximal fever usually in older people. The patient is usually unable to weight bear and has a shortened externally rotated limbs Wrist Fracture – Colles fracture. Sometimes there is height loss and kyphosis.

7. Investigation Conventional plain radiograph: It is useful along with CT or MRI, for detecting complications of osteopenia Bone biopsy: Tetracycline labelling of the skeleton on bone biopsy determines the rate of skeletal growth Biochemical markers: Markers for bone formation are serum bone-specific alkaline phosphatase, serum osteocalcin, serum propeptide of type I procollagen, Markers for bone resorption are urine and serum cross-linked N-telopeptide, urine and serum cross-linked C-telopeptide and urine total free deoxypyridinoline

8. Bone mineral density (BMD) : It is a measure of the mineral content of bone Methods used to measure BMD * Dual energy X-ray absorptiometry: It measures areal bone density,It uses low doses of radiation and is the ‘gold standard’ for the diagnosis of osteoporosis. Results from DXA are expressed as either the T-score or the Z-score. *Quantitative ultrasound *Quantitative CT scanning

9. Treatment The aim of treatment is to reduce the risk of fracture It includes 1) diagnosis of individuals at highest risk 2) exclusion of secondary causes of osteoporosis 3) selecting appropriate treatment Pharmacological Management: The two main classes of drug used 1) antiresorptive agents 2) anabolic agents

10. Antiresorptive agents : They block bone resorption by inhibiting the activity of osteoclasts. These include bisphosphonates,raloxifene, and calcitonin. Bisphosphonates include i alendronic acid, risedronate, pamidronate ,etidronate. anabolic agents: They stimulate bone formation by acting primarily on osteoblasts. These include parathyroid hormone and teriparatide.

11. Prevention Nutrition:Sufficient daily calcium intake (1200–1500 mg/day) and vitamin D Cessation of smoking Reduction in alcohol intake Increase weight bearing exercise

12. Thank you