Bone Pain Flashcards
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
What is the main action of parathyroid hormones?
Increase serum calcium
- activates osteoclasts by causing increased rank ligand expression on osteoblasts
- increases resorption of calcium by the renal tubules and increases urinary excretion of phosphate
- increases synthesis of vitamin D
What is the most common cause of asymptomatic hypercalcaemia?
- primary hyperparathyroidism
What is primary hyperparathyroidism usually caused by?
Sporadic parathyroid adenoma (benign tumours starting in the epithelial tissue of a gland or gland-like structure) and less commonly by a parathyroid hyperplasia and parathyroid carcinoma
How is hypercalcaemia detected?
By routine blood tests
What is secondary hyperparathyroidism caused by?
It is caused by hypercalcaemia secondary to renal failure and the parathyroid glands are hyperplastic
Is primary or secondary hyperparathyroidism more severe?
Primary
What is the most common cause of symptomatic hypercalcaemia
Malignancy
What are the clinical effects of parathyroid adenoma?
- Bone resorption - osteoporosis
- Brown tumour of hyperparathyroidism
- Osteitis fibrosa cystica (widespread resorption of bone leading to fibrosis and formation of cystic spaces)
- Nephrolithiasis - kidney stones
- Nephrocalcinosis - metastatic calcification of renal tubules
- GIT disturbances - constipation, peptic ulceration, acute pancreatitis
- CNS disturbance > depression and seizures
What are the clinical features of Paget’s disease?
- bone pain in pelvis, spine and femur
- Deformity
- Skull becomes so heavy that it becomes difficult to lift the head (Leontiasis ossea)
- Chalk stick fractures of legs, compression fractures of spine and kyphosis (hunchback)
- Elevated alkaline phosphatase
- Anterior bowing of femurs and tibiae (distorting femoral heads causing secondary osteoarthritis)
Paget’s disease is life threatening. TRUE or FALSE
FALSE
What is the pathogenesis of Paget’s disease?
- 50% of familial disease and 10% of sporadic(isolated) cases have a mutation in the SQTM1 gene which increases activity of nuclear factor kappa beta, which in turn increases osteoclast activity
- viral infections
- activation of mutations in RANK and inactivating mutations in OPG causes juvenile Paget’s disease
Why are bones affected by Paget’s disease more likely to be fractured?
Because the bones are denser meaning they cannot resist deformity as much and break
Who is renal osteodystrophy (mineralisation deficiency) seen in?
chronic renal disease - damaged kidney can not transport vitamin D in its active form (causes hypocalcaemia)
What does renal osteodystrophy cause?
- associated with osteomalacia
- can cause osteosclerosis
- growth retardation
- osteoporosis
- increases osteoclastic bone resorption
What is the treatment for osteomalacia and rickets?
- vitamin D replacement
What investigations should you take for osteomalacia?
- can be seen in laboratory investigations:
- low/normal calcium
- low/ normal phosphate
- raised serum alkaline phosphate
- low serum vitamin D
- raised parathyroid hormone levels
- low urinary calcium excretion
X-ray changes can also be seen e.g incomplete fractures
What are the clinical features of osteomalacia?
- bone pain
- lethargy (lack of energy)
- severe localized pain
- proximal myopathy (muscle disease/muscle weakening)
- skeletal deformity
- fracturing
Growth is impaired in children with rickets. TRUE OR FALSE
TRUE
What radiological changes are seen in patients with rickets?
- thin cortices
- widened growth plates
- delayed opacification of the epiphysis
What are the clinical features of osteoporosis
- deformity
- bone pain
- immobility due to fractures
- OSTEOPOROSIS IS USUALLY ASYMPTOMATIC AND THEREFORE THE IMPORTANCE OF TREATMENT TO PREVENT FRACTURES MUST BE EMPHASIZED TO PATIENTS
How is Paget’s disease investigated and diagnosed?
- serum alkaline phosphatase will be elevated
- plain radiographs show areas of disorganized bone with areas of lysis and sclerosis (cortex is usually thickened)
- isotope bone scans often show multiple areas of focal increased uptake and are most sensitive test for detecting pagetic lesions
What are lesions?
Damage to any tissue
What are the red flags in pagetic lesions?
Pagetic bone is highly vascular and bleeds a lot during surgery so patients are cross matched for blood in advance of planned surgery and blood is made available for emergency situations
How is paget’s disease treated?
- bisphosphonates are effective in inhibiting bone resorption and reducing the symptoms of Paget’s disea.se
- asymptomatic disease should only be monitored
- surgical treatment is used to manage complications
- e.g surgical stabilization, osteotomy( cutting and reshaping bone)
What are the main management techniques for osteoporosis/osteopenia?
- Modification of risk factors
- Drug therapies e.g bisphosphonates, denosumab, teriparatide etc.
- prevention of falls as most osteoporotic fractures are caused by falls
Why are elderly patients more predisposed to falls?
- aging process leads to slower reaction time
- poor mobility
- poor eyesight
- medical comorbidities e.g cardiac arrhythmia
- inadequate/unsafe housing environment