Bone Pain Flashcards
(125 cards)
What is osteopenia?
Decreased bone mass
1-2.5 SD of bone mass is below mean peak bone mass
What is osteoporosis?
It is osteopenia but the bone density is so little that it can increases the risk of a bone fracture
(>2.5 SD of bone mass is below mean peak bone mass)
Name the 2 types of primary osteoporosis and describe them
- Senile osteoporosis (when there is an imbalance between bone resorption and bone formation)
- Post- menopausal osteoporosis
Name the 3 types of secondary osteoporosis
- Endocrine disorders (hypothyroidism)
- Gastrointestinal disorders (Eating disorders/Malnutrition)
- Drugs (Corticosteroids)
What causes osteoporosis?
- Age related changes (adults osteoblasts do not respond to growth factors as much and can therefore not reform as much bone)
- Reduced physical activity (low magnitude influences bone density and weight exercises increased bone mass more than repetitive activities do (e.g cycling)
- Genetic factors (polymorphism has been linked to osteoporosis
- Adolescents that have low calcium intake and low vitamin D (reduces bone mass)
- Hormonal influences
What do WNT ligands do?
They stimulate bone growth
What are the main complications of osteoporotic fractures?
- Pulmonary embolism
- Pneumonia
Why do thromboembolisms form?
Due to the activation of the coagulation cascade which forms blood clots that can move to the heart
Why do patients that have hip fractures develop infections (Acute bronchopneumonia)
Because the patient is in pain which reduces their ability to cough and their mobility
What bacteria cause acute bronchopneumonia? Name 3
- staphylococcus aureus
- streptococcus pyogenes
- pseudomonas
What are the 2 vitamin D related disorders?
- Rickets disease
- Osteomalacia (result of unmineralized matrix)
Name some features of vitamin D
- Fat - soluble vitamin that is found in beef, cheese and salmon
- Maintains adequate plasma levels of calcium and phosphorus to support metabolic functions, bone mineralisation and neuromuscular transmissions
What is rickets disease caused by?
Deficiency of vitamin d and inadequate mineralization of children’s bone, where their epiphysis has not closed
What is osteomalacia?
Inadequate mineralization of the bone > causes softening of the bone
What is the major source of vitamin D for humans?
Synthesis in the skin
What are the main functions of vitamin D?
- In normal calcaemic states - it is required for calcium deposition
- Stimulates intestinal absorption of calcium in enterocytes and calcium reabsorption in distal renal tubules
- Upregulates Rank-ligand on osteoclasts which active rank receptors on osteoclast precursors causing differentiation into osteoclasts and bone resorption
- Promotes mineralisation of bone by stimulating osteoblasts to synthesise the calcium binding protein, osteocalcin, which promotes calcium deposition
What is vitamin D deficiency caused by?
- limited exposure to sunlight -by diets deficient in calcium and V.D
- malabsorption or renal disorders (can cause hypocalcaemia)
Vitamin D deficiency can cause bone fractures and bone loss in the elderly. TRUE OR FALSE
TRUE
In rickets ..(1).. unmineralised bone matrix causes ……(2)…
- Excess
2. Skeletal deformity
What does the inadequate calcification of the epiphyseal cartilage cause?
- causes overgrowth of the epiphyseal cartilage which causes irregular masses of cartilage which could project into the marrow cavity
- Deposition of osteoid matrix on inadequately mineralised cartilaginous remnants
- Can cause enlargement of the osteochondral junction
Name the clinical features of rickets
- Wide joints e.g hips, wrists and ankle
- Prominent forehead
- Bowing of limbs
- Rachitic rosary
- Enlarged epiphysis
What is most commonly affected by osteomalacia in the body?
The neck of femur and vertebral bodies
What other cells can produce vitamin D?
- macrophages, keratinocytes and tissues such as breast, prostate and colon can produce 1,25 - dihydroxyvitamin
Name some non skeletal effects of vitamin d
- immune cell differentiation and enhance inflammation
- inhibits tumour cell proliferation, induces differentiation and inhibits angiogenesis