Paget's Disease of Bone Flashcards
1
Q
Define Paget’s disease of bone
A
A chronic bone disorder that is characterised by focal areas of increased bone remodelling, resulting in overgrowth of poorly organised bone
2
Q
Explain the aetiology / risk factors of Paget’s disease of bone
A
Divided into three stages:
- Osteolytic (osteoclast predominant)
- Osteolytic-osteosclerotic (osteoblasts try to rebuild bone)
- Quiescent osteosclerotic (there is disorganised, mineralised bone)
Aetiology:
- Paget’s is characterised by accelerated and disorganised but localised bone remodelling
- Excessive bone resorption (osteoclastic overactivity) is followed by a compensatory increase in bone formation (osteoblasts) IN a woven structure
- New bone formed = WOVEN bone structurally disorganised and mechanically weaker than normal adult lamellar bone
- This leads to BONE FRAILTY, HYPERTROPHY & DEFORMITY
Risk Factors:
- Over 50
- Paramyxovirus/Measles
- FHx of Paget’s (autosomal dominant)
3
Q
Epidemiology
A
- Age of onse over 55
- No sex predilection
4
Q
Recognise the presenting symptoms of Paget’s disease of bone
A
- Mostly ASYMPTOMATIC
- Sensorineural hearing loss (temporal bone hypertrophy)
- Fragility fractures
- Bone pain
- Facial pain
- Sciatic pain
5
Q
Recognise the signs of Paget’s disease on physical examination
A
- Warm skin over bone
- Bone deformities (frontal bossing, prognathism/mandibular protrusion)
6
Q
Identify appropriate investigations for Paget’s disease of bone and interpret the results
A
- Plain X-ray:
- Lytic changes (mainly in the skull OSTEOPOROSIS CIRCUMSCRIPTA)
- Bowing of long bones
- Cotton wool spots in the skull
-
Technetium 99 bone scan
- Areas of dense uptake of Tec99 show pagetic bine
- Total/Bone-specific ALP: Elevated
- LFTs: Monitor if liver disease is causing raised ALP
- Serum P1NP: bone formation marker (RASIED)
- Serum CTX: bone resorption markrer (RAISED)
7
Q
Management
A
IV Zolendronate and monitor ALP every 6-8 months
