MSK

Question 1

Osteoporosis
- risk factors
- investigations
- Mx

Answer 1

Risks: (SHATTERED)
Steroid use
Hyperthyroid/hyperparathyroid
Alcohol/smoking
Thin (BMI <22)
Testosterone reduced (e.g., anti-androgen therapy)
Early menopause
Renal failure/liver failure
Erosive/inflammatory bone disease (e.g., rheumatoid arthritis)
Dietary calcium deficiency/type 1 diabetes

Investigations:
* Bloods—Calcium, phosphate alkaline phosphatase, vitamin D, thyroid function
* Imaging—Dual-energy X-ray absorptiometry (DEXA) is the gold standard. Bone density at the hip is compared to the standard of a young healthy adult to give a T score ( ≤2.5 is indicative of osteoporosis).

Mx:
* Bisphosphonates (e.g., alendronic acid, risedronate) inhibit osteoclast bone resorption. Side-effects include dysphagia and gastric ulcers.
* Denosumab is a monoclonal antibody that reduces osteoclast activity and is used if bisphosphonates are not tolerated.
* Hormone replacement therapy can prevent but not treat osteoporosis in postmenopausal women.

Question 2

Osteomalacia
- causes
- investigations
- treatment

Answer 2

Causes:
* Vitamin D deficiency
* Renal failure
* Liver failure
* Drugs—Liver enzyme induction (e.g., anticonvulsants)
* Tumours

• Bloods
• Bone profile—Typically low vitamin D, low/normal calcium, low phosphate, high alkaline phosphatase
• Parathyroid hormone is typically high.
• Check renal function.
• Imaging—X-ray for loss of cortical bone, looser/milkman pseudofractures (partial undisplaced fractures)

Mx:
* Calcium and vitamin D3 supplementation (if diet is insufficient)
* Alfacalcidol or calcitriol for renal disease (monitor for hypercalcaemia)
* Ergocalciferol or calcitriol for hepatic disease or malabsorption

Question 3

Pagets disease of the bone
- Sx
- Investigations
- Mx

Answer 3

Symptoms:
* Commonly asymptomatic (around 70% of cases) and found incidentally
* Bone pain and deformity are the most common symptoms; most commonly skull, lumbar spine, pelvis, femurs, or tibia.
* Classically associated with a sabre tibia

Investigations:
Blood results
* Bone profile—Alkaline phosphatase markedly raised, phosphate normal, calcium normal or raised
* Parathyroid hormone—Usually normal
* Imaging
* X-ray—Localised enlargement, deformity, osteolysis (radiolucency), and sclerosis
* Radionuclide bone scans—High uptake in affected area

Management:
* Analgesia—Paracetamol and NSAIDS
* Anti-resorptive therapy—Bisphosphonates (e.g., alendronate to correct calcium and vitamin D prior to starting)
* Surgery can be required for severe deformity or nerve compression.
* Orthotics can be useful to reduce pain and improve mobility.

Question 4

What is the typical cause of a fracture to the 5th metacarpal (base of little finger)?

Answer 4

Punching someone - Boxers fracture