Osteoporosis

Systemic skeletal disease characterized by low bone mass and deterioration of bone microarchitecture, leading to bone fragility and increased fracture risk (diagnosed by a bone density T-score ≤ -2.5 on DEXA).

• Extremely common in older adults (especially postmenopausal women) and a major cause of fragility fractures. These fractures (e.g., hip fractures) result in significant morbidity (loss of independence, chronic pain) and even mortality, so early detection and prevention are crucial.

• Often silent until a fracture occurs – typical fragility fractures (from minimal trauma like a standing-height fall) include those of the hip, vertebrae (compression fractures), or distal radius (wrist).
• Vertebral fractures cause chronic back pain, loss of height, and kyphosis (Dowager hump). A patient may notice their posture stooping and clothes fitting differently due to height loss. Hip fractures usually present after a minor fall with acute hip pain and inability to bear weight.
• Risk factors: age (elderly), female (postmenopausal estrogen loss), low body weight or frailty, smoking, excess alcohol, family history, and long-term glucocorticoid use. (Men with osteoporosis often have a secondary cause such as chronic steroid use, hypogonadism, hyperthyroidism, or alcoholism.)

1. Screening: All women ≥65 (and younger women with high risk) should undergo bone density testing. Men ≥70 or those with significant risk factors may also be screened.
2. Confirm diagnosis with DEXA (dual-energy X-ray absorptiometry) of hip and spine. Interpret the T-score: ≥ -1.0 is normal, -1.0 to -2.4 = osteopenia, ≤ -2.5 = osteoporosis. A fragility fracture at this bone density indicates severe osteoporosis.
3. Lab workup: Check for secondary causes if suspicion arises – e.g., serum calcium, 25-OH vitamin D, TSH (thyroid), PTH (parathyroid), testosterone in men, and renal function. This helps rule out conditions like hyperthyroidism, hyperparathyroidism, vitamin D deficiency (osteomalacia), or multiple myeloma contributing to bone loss.
4. Risk assessment: Use the FRAX calculator (or similar tools) to estimate 10-year fracture risk based on BMD and clinical factors. High risk (e.g., hip fracture risk ≥3% or major osteoporotic fracture ≥20%) can guide the decision to treat even if BMD is in osteopenia range.

1. Lifestyle is foundational: adequate calcium and vitamin D intake, regular weight-bearing exercise (to strengthen bone), smoking cessation, limiting alcohol, and fall prevention measures (home safety, vision correction, assistive devices if needed).
2. Bisphosphonates are first-line pharmacotherapy – e.g., alendronate (oral) or zoledronic acid (IV) – these anti-resorptive drugs inhibit osteoclasts and substantially reduce hip, spine, and wrist fracture risk.
3. Other options: SERMs like raloxifene (selective estrogen receptor modulator) for postmenopausal women primarily needing spine protection; denosumab (RANKL inhibitor) for high-risk patients intolerant of bisphosphonates; teriparatide (PTH analog) or abaloparatide – anabolic agents used in severe cases to build bone. Hormone replacement therapy (estrogen) can prevent bone loss in recently menopausal women but is not first-line due to risks.

• Mnemonic ACCESS for key osteoporosis risk factors: Alcohol use, Corticosteroid use, Calcium low (dietary deficiency), Estrogen low (postmenopause), Smoking, Sedentary lifestyle.
• Often called a 'silent disease' because no symptoms until a fracture occurs – osteoporosis itself doesn't cause bone pain. Diffuse bone pain suggests another issue (like osteomalacia or bone metastases).
• Glucocorticoids (e.g., prednisone) are notorious for causing secondary osteoporosis – always consider bone protection (calcium/Vit D supplements, bisphosphonates) when patients are on long-term steroids.

• Fragility fracture occurrence (e.g., hip or multiple vertebral fractures) is a red flag signaling advanced osteoporosis – it confers high short-term mortality/morbidity risk and necessitates urgent management (surgical fix for hip, aggressive osteoporosis treatment).
• Osteoporosis in an atypical population (men, premenopausal women, or anyone under 50) should raise suspicion for a secondary cause – evaluate for underlying issues like hyperthyroidism, Cushing syndrome, malabsorption, or malignancy.

1. Risk factors or age ≥65 (women) → screen for osteoporosis (DEXA).
2. If DEXA shows T-score ≤ -2.5 or patient has a low-trauma fracture → diagnose osteoporosis.
3. For T-scores in osteopenia range, calculate FRAX risk; high fracture risk may warrant treatment even without full osteoporosis-range BMD.
4. Rule out reversible causes: address low vitamin D, manage thyroid or parathyroid disorders, and modify any contributing medications (like chronic steroids).
5. Initiate treatment: lifestyle modifications for all, plus pharmacotherapy (bisphosphonates or other agents) for diagnosed osteoporosis or high-risk osteopenia; follow up with periodic DEXA to monitor bone density.

• Thin, elderly woman with a dowager's hump (increased thoracic kyphosis), loss of height, and a history of wrist and vertebral compression fractures → Osteoporosis (postmenopausal type).
• Patient with rheumatoid arthritis on long-term prednisone who presents with a low-impact hip fracture → Glucocorticoid-induced osteoporosis (secondary osteoporosis).
• 75‑year‑old who slips on ice, falls from standing height, and sustains a femoral neck hip fracture → fragility fracture due to osteoporosis.