Osteoporosis Flashcards
what is the definition of osteoporosis?
Osteoporosis is a complex skeletal disease characterised by low bone density and micro-architectural defects in bone tissue, resulting in increased bone fragility and susceptibility to fracture
what is the epidemiology of osteoporosis?
50% of women over 50
20% of men over 50
More common in white women over 50
what is the aetiology of osteoporosis?
Low bone mass can be the result of low peak bone mass or loss of bone mass with ageing. Fragility of bone is not fully explained by low bone mass or bone density (mass/volume). The quality of bone micro-architecture also contributes to bone strength. Bone remodelling and mineralisation are important determinants of the quality of bone micro-architecture.
Falls (elderly)
what are the risk factors for osteoporosis?
Women Increasing age (50 in women, 70 in men) White Prior fractures Low BMI / weight loss - (reduced skeletal loading) Family history, material hip fractures Loss of height (reduced skeletal loading) Post menopause Secondary amenorrhoea Primary hypogonadism Smoking Excessive alcohol use Prolonged immobilisation (reduced skeletal loading) Corticosteroid use Low calcium intake Vit D deficiency Glucocorticoid excess Depo-provera contraception Aromatase inhibitors GnRH analogues Inflammatory disease, endocrine disease (cortisol)
what is the pathophysiology of osteoporosis?
Bone mineral density and bone size leads to bone strength, decreases with age
Bone quality affected by bone turnover, architecture and mineralisation
- Bone mass decreases with age, but will depend on the ‘peak’ mass attained
in adult life and on the rate of loss in later life
- Genetic factors are the SINGLE MOST SIGNIFICANT INFLUENCE on peak
bone mass
- Multiple genes are involved, including collagen type 1A1, vitamin D receptor
and oestrogen receptor genes
- Nutritional factors, sex hormone status and physical activity also affect
peak bone mass
In postmenopausal women with an oestrogen deficiency, the overexpression of RANKL activity overrides the natural inhibitory activity of OPG. This disequilibrium in bone remodelling leads to high bone turnover, calceos bone loss, lower bone density and bone quality, which culminates in bone fracture.
With age, vertical trabeculae are maintained by losing horizontal trabeculae, reducing overall strength
what are the key presentations of osteoporosis?
Fractures (wrist, hip, vertebrae)
Presence of risk factors
what are the signs of osteoporosis?
Kyphosis (curvature of spine)
what are the symptoms of osteoporosis?
Back pain
Impaired vision
Impaired gait, imbalance, lower extremity weakness
Vertebral tenderness
what is the first line and gold standard investigating for osteoporosis?
DXA (dual-energy x-ray absorptiometry) - T-score determined (standard deviation care, how far from the average young adult), T-score of ≤-2.5 indicates osteoporosis; T-score ≤-2.5 with fragility fracture(s) indicates severe (or established) osteoporosis, -1-2.5 indicated osteopenia
X-ray - fractures
Bloods - Ca2+, phosphate and alkaline phosphate all normal
what other tests could be done for osteoporosis?
FRAX (fracture risk assessment tool)
what are the differential diagnoses for osteoporosis?
Multiple myeloma
Osteomalacia
CKD
how is osteoporosis managed?
lifestyle changes
Antiresorptives - Bisphosphonate (aldendronate, risedronate, zoledronate), HRT, denosumab
Anabolic - Teriparatide
Non glucocorticoid induced women:
Bisphosphonates, calcium and vitamin D supplements, denosumab (MCA), parathyroid hormone receptor agonist (teriparatide), antiresorptive agent
SERM, calcium and vit D supplements, HRT
Intranasal calcitonin, calc and vit D supplements, congested oestrogens, romosozumab
Non glucocorticoid induced men:
Bisphosphonate, cal and vit D supplements, testosterone, teriparatide, antiresorptive agent
Denosumab, cal and vit D supplements
Glucocorticoid induced:
Bisphosphonate, cal and vit D supplements, teriparatide, denosumab
how is osteoporosis monitored?
Allow 2 years between follow up DXAs
what are the complications of osteoporosis?
Hip fractures Rib fractures Wrist fractures Chronic pain Femoral fractures (bisphosphonate treatments)
what is the prognosis of osteoporosis?
Fractures cause morbidity and mortality (decreased level of motility by 1 level after hip fracture)
With preventative treatment, fragility fractures of the hip, vertebrae, and wrist can be avoided.
Prognosis is good for people at risk of osteoporosis if steps are taken to prevent decline in bone density and strength
