Osteoporosis Flashcards
What is osteoporosis?
A systemic skeletal disease characterised by low bone mass and deterioration of bone tissue, with consequent increase in bone fragility and susceptibility to fracture.
What is the presentation of osteoporosis?
Most pts unaware they have it till sustain fracture
(Silent till fracture sustained)
What are the common sites of fractures from osteoporosis?
Hip
Clinical vertebrae
Forearm
Woman more likely to sustain fractures then men.
What are the risk factors for osteoporosis?
Age - over 50 for women and 65 for men
Low bone density (modifiable)
Steroid
Hyperthyroidism and hyperparathyroidism
Alcohol and smoking
Thin (BMI<22)
Testosterone deficiency
Early menopause
Renal/liver failure
Erosive/inflammatory bone disease
Diabetes
Family history
What is the investigation for osteoporosis?
DEXA scan - T score less than -2.5 = osteoporosis, score -1.5 = osteopenia
Tests for underlying causes:
FBC, ESR/CRP
Serum calcium (albumin)
Alkaline phosphatase
Liver tests
Thyroid
Myeloma screen
25-hydroxyvitamin D
PTH
Endocrine - oestrogen, diabetes, cortisol
GI - coeliac disease antibodies
Markers of bone turnover
Plain radiogram , MRI, isotope bone scan
What is the pathology of osteoporosis?
Imbalance of osteoblastic and osteoclastic activity - measured in bone modelling units (BMUs)
Age related - osteoblasts in elderly have reduced proliferation, biosynthetic potential and response to growth factors = diminished capacity to make bone.
Reduced physical activity - mechanical forces stimulate normal bone remodelling
Hormonal influences - reduced oestrogen increases bone resorption
What is the management of osteoporosis?
Drugs:
Bisphosphonates- alendronic acid, zolendronic acid, risedronate, ibandronate
Ca supplements and Vit D
Denosumab - given ever 6 months, targets RANKL, reduces rate of bone loss
Teriparatide (anabolic)
Raloxifene
HRT
strontium ranelate - reduces rate of boen turoner and stimates bnoe growth
Lifestyle advice:
Stop smoking
Diabetic control
Diet - vit D, Ca, protein
Weight-loss
Weight-bearing exercises
Hip protectors in nursing homes
DEXA scan?
Dual energy x-ray absorptiometry
Low dose radiation
Measure 2 sites - lumbar spine, left hip
T or Z score given
What is T score?
Difference between mean bone density between the patient and a healthy young women.
What is z score?
Compares bone density with that of a heathy aged matched women/ control .
What is osteogenesis imperfecta?
Syndrome of bone fragility due to mutations on type 1 collagen gene.
Mostly caused by dominant gene defect
What is the treatment for osteogenesis imperfecta?
Preventing/controlling symptoms
Maximzing independent mobility
Developing optimal bone mass and muscle strength
Care of fractures
Braces, wheelchairs and other moiety aids commonly used
Symptoms of osteogenesis imperfecta?
Frequent fractures
Coloured sclera
Hypermobility with laxity of joints and muscles
Bone deformity
Scoliosis
Brittle teeth
Deafness
Respiratory failure - due to vertebral and rib fractures
Collagen abnormalities
Stature abnormalities
