Complications

Complications are seen in around 30% of patients (1).

• fractures
  • a frequent complication of Paget's disease
  • most commonly arise in the weight-bearing long bones
  • typically transverse in nature (similar to a piece of chalk that has snapped) (1)
  • those in the femur are associated with a high rate of non - union
  • small stress fractures are often very painful.
  • on X-ray, they resemble Looser's zone
• osteoarthritis
  • is not uncommon in the hip or knee
  • thought to be primarily a consequence of the remodelling process rather than of abnormal loading from deformity
  • pain caused by arthritis of the hip which results in impaired mobility is the most common cause of hip replacement in Paget's patients (1)
• osteosarcoma
  • is a serious complication, occurring in about 1% of patients
  • the tumour is particularly invasive and most commonly affects the jaw, pelvis or femur
  • it may be the first presentation of Paget's and should be suspected in any elderly patient in which a previously diseased bone becomes increasingly painful, swollen and tender.
• high output cardiac failure
  • occurs rarely
  • most common in polyostotic disease and is the result of increased bony blood flow.
• hypercalcaemia
  • seen in patients whom are immobilised for long periods
• impaired vision, facial palsy, trigeminal neuralgia and deafness are all consequences of cranial nerve compression.
• radiologically both sclerotic and lytic phases are recognized; the lytic phase may be defined in the calvarium of the skull where it is called osteoporosis circumscripta.

Reference:

• (1) Singer FR. Paget disease: when to treat and when not to treat. Nat Rev Rheumatol. 2009;5(9):483-9.