Osteoporosis

Osteoporosis is a disorder of reduced bone strength: bone mass falls and the internal trabecular network deteriorates. A bone may look intact on the outside yet fail when ordinary loading is applied, much like a bridge whose supporting struts have progressively thinned. Bone is continually remodelled. Osteoclasts remove older bone, and osteoblasts replace it. When resorption persistently exceeds formation—commonly after estrogen loss, with aging, glucocorticoid exposure, malabsorption, endocrine disease, or immobility—structural reserves decline. The clinical consequence is not simply a low DXA value; it is a higher probability of fracture. A fragility fracture occurs with low trauma, usually a fall from standing height or less. The hip, vertebrae, proximal humerus, and distal forearm are classic sites. Vertebral fractures are especially easy to miss because many cause no dramatic acute event. A patient may describe “shrinking,” worsening kyphosis, persistent mid-back pain, or clothes fitting differently rather than reporting a fracture. Pain alone does not identify osteoporosis. Diffuse musculoskeletal pain without fracture, inflammatory findings, or height loss should prompt consideration of other causes rather than attribution to low bone density. Osteoporosis is...