Paget's Disease of Bone Flashcards
What is Paget’s disease of bone characterised by
Increased bone turnover
Most patients of Paget’s disease are extremely symptomatic. True or False
False - most are asymptomatic
What sex are affected more with Paget’s disease
Men and women are affected equally
In what areas of the world is Paget’s disease more common
Areas of the world with large concentrations of people of Anglo-saxon origin
Rare in asia, africa and scandinavia
What results in an abnormal “mosaic” pattern of lamellar bone
Excessive bone resorption by abnormally large osteoclasts followed by increased bone formation by osteoblasts in a disorganised fashion
How is a diagnosis of Paget’s disease obtained
Plain radiograph for some other reason
or Biochemistry for some other reason showing raised alkaline phosphatase
Where are the most commonly affected areas of Paget’s disease
pelvis
spine
skull
long bones (proximal and distal)
can Paget’s disease spread from one bone to the next
No - the distribution within their skeleton is likely to remain fixed
What might pain be due to in Paget’s disease
periosteal stretching caused by bone enlargement, micro fractures or secondary degenerative arthritis
What might some patients complain of
headache due to skull involvement
Describe the changes seen in Paget’s
enlarged and abnormally contoured bones e.g. anterior bowing of the tibia and anterolateral bowing of the femur
What are fractures sometimes associated with
substantial acute blood loss
Patients with Paget’s have a 1% increase in developing what
osteosarcoma
What is a marker of increased bone formation
serum alkaline phosphatase
What feature may be seen in the early stages of Paget’s disease
Lytic lesions
What does chaotic bone formation result in that can be seen on radiograph
lack of distinction between the cortex and medullary bone
What feature is helpful in differentiating Paget’s disease from sclerotic metastases
The affected bones are expanded but in sclerotic metastases, the bone is of normal size
What causes a cotton wool appearance
disruption of normal bone architecture
What is useful in determining the extent of skeletal involvement, but is not specific for diagnosis
Radioisotope bone scanning
What are Paretic bone lesions seen as
hot spots
What is the primary indication for treatment in Paget’s disease
presence of symptoms
What should be done if there is doubt about where the pain is coming from in a Patient with both osteoarthritis and Paget’s disease
Prescribe NSAIDs and paracetamol
What do drugs used to treat Paget’s disease do
suppress osteoclastic activituy
Why are bisphosphonates used as first line
Superior efficacy compared with calcitonin and their minimal side effects
What bisphosphonate is the drug of choice and how is it administered
IV pamidronate may be given fortnightly
This usually suppresses disease activity for 12-18 months
What are some side effects of pamidronate
Low grade fever and flu-like symptoms in the first 1-2 days in 20% of patients
Hypocalcaemia
Rare side effects include ocular complications (conjunctivitis, uveitis, scleritis) and osteonecrosis of the jaw
What is the main down side of using oral risedronate
may cause oesophagi’s
How is calcitonin administered
subcutaneously at bedtime
the dose is then reduced and only given every other day
What is the disadvantage of calcitonin
patients become resistant due to the development of antibodies
What are some side effects of calcitonin
Nausea
facial flushing
metallic taste
What type of surgery is sometimes beneficial for patients with refractory pain
Elective surgery for joint replacement
tibial osteotomy
internal fixation of pathological fractures
What should be measured initially every other month and then once or twice a year with good clinical response
serum alkaline phosphatase
When are repeat bone scans and radiographs not necessary
Never unless the patient has new or progressive symptoms
