Synopsis
Distinguish active pagetic bone pain from mechanical joint and fracture complications, map affected sites and coordinate antiresorptive treatment with safe deformity, fixation and arthroplasty planning.
- Paget disease is focal accelerated remodelling that produces expanded, hypervascular and mechanically disorganised bone, commonly affecting pelvis, spine, femur, tibia and skull.
- First-line confirmation uses radiographs of suspected sites plus total ALP with liver tests; normal ALP does not exclude limited monostotic disease.
- After characteristic radiographic diagnosis, radionuclide bone scintigraphy is the reference test for mapping active skeletal extent, with radiographic correlation of unexpected uptake.
Key red flags
A new fracture through expanded femur or tibia can bleed, displace and be technically difficult to stabilise; protect the limb and refer urgently.
Investigation priorities
Confirm characteristic architecture, identify deformity and fracture and screen for an aggressive alternative.
Management branches
Characteristic symptoms, incidental imaging or isolated bone-source ALP raises suspicion.
- Obtain targeted radiographs and total ALP with liver, calcium, phosphate, renal and vitamin-D tests.
- Confirm typical anatomy before ordering a radionuclide scan to map active skeletal distribution.
Key medicines
Zoledronic acid preferred active-disease bisphosphonateGive a single 5 mg intravenous infusion over at least 15 minutes after confirming suitable creatinine clearance, hydration, corrected calcium and adequate vitamin-D and calcium intake.
Risedronate alternative oral bisphosphonateWhere intravenous treatment is unsuitable, a specialist may use risedronate 30 mg orally once daily for two months, taken fasting with plain water while upright according to the product instructions.