Metabolic Bone Diseases Flashcards
This deck covers:
Paget’s Disease
Rickets/Osteomalacia
Osteogenesis Imperfecta
What is Paget’s Disease?
A localised disease of increased bone turnover.
Resorption increases and leads to increased formation
What effect does Paget’s disease have on bone?
It becomes extremely disorganised:
- Bigger
- Less Compact
- More vascular
- More susceptible to deformity & fracture
How are you likely to see a case of Paget’s disease?
70% of cases are asymptomatic so the commonest finding is an elevated serum ALKP
- Deep boring bone pain & local heat
- Bone deformity or fracture
- Nerve damage (mostly hearing loss)
- ~Osteosarcoma
How do we test for Paget’s disease?
Blood tests:
- ALKP raised
- Ca & PO4 normal
Can x-ray for lytic lesions and thickened bone cortices
How do we treat Paget’s Disease?
Analgesia is first line, if it’s asymptomatic after that don’t fuck with it.
If analgesia isn’t sufficient:
- IV bisphosphonates
What are rickets and osteomalacia?
Diseases of insufficient bone mineralisation due to a deficiency of Vit D or Ca
In this there is still a normal bone volume but it is unmineralised. In osteoporosis its the opposite.
What’s the difference between rickets and osteomalacia?
Rickets occurs in growing kids
Osteomalacia occurs in adults after closure of the epiphyseal plates
They present differently
How would a case of rickets present in an infant?
Growth retardation
Apathy and hypotonia
They may also show deformities e.g. wide joints, odd shaped ribs, persistant fontanelles & oddly curved spine
Kids with rickets are obviously ill
How might rickets change when a child starts walking?
Can notice bow legged or knock kneed as well as the aforementioned:
- Growth retardation
- Wide joints (elbows, wrist, ankles)
- Curved spine
- Large forehead/fontanelles
How might osteomalacia present?
In adults with:
- Bone pain/tenderness
- Proximal myopathy (waddling gait)
- Increased falls & fractures
How do we test for Rickets & Osteomalacia?
Bloods:
- Low calcium
- Low phosphate
- high PTH
- high ALKP
Bone biopsy
How do we treat Rickets & osteomalacia?
Look for any thing that could cause a deficiency e.g. Liver damage, anti-convulsant drugs, renal failure or malabsoption disorders
Assuming it’s a primary deficiency then treat with Ca & Vit D supplements
What is Osteogenesis Imperfecta?
A genetic disorder of absent/defective type 1 collagen that is characterized by fractures due to mild trauma or activities of daily living
When does OI onset?
Can be from pre-natally fatal all the way up to 40yr olds diagnosed with “Early onset OP”
