Paget's Disease of Bone Flashcards
What is Paget’s Disease of Bone?
Paget’s disease of bone refers to a disorder of bone turnover.
There is excessive bone turnover due to excessive activity of both osteoblasts and osteoclasts.
This excessive turnover is not coordinated, leading to patchy areas of high density (sclerosis) and low density (lysis).
This results in enlarged and misshapen bones with structural problems that increase the risk of pathological fractures.
It particularly affects the axial skeleton (the bones of the head and spine).
Clinical presentation
Paget’s disease typically affects older adults.
Bone pain
Bone deformity
Fractures
Hearing loss can occur if it affects the bones of the ear
Key investigations
X-ray
Biochemistry
X-ray features
Bone enlargement and deformity
“Osteoporosis circumscripta” describes well defined osteolytic lesions that appear less dense compared with normal bone
“Cotton wool appearance” of the skull describes poorly defined patchy areas of increased density (sclerosis) and decreased density (lysis)
“V-shaped defects” in the long bones are V shaped osteolytic bone lesions within the healthy bone
Biochemistry findings.
Raised ALP
Normal calcium
Normal phosphate
Management of Paget’s
Bisphosphonates are the main treatment.
They are generally very effective. They interfere with osteoclast activity and seem to restore normal bone metabolism. They improve symptoms and prevent further abnormal bone changes.
Other measures include:
NSAIDs for bone pain
Calcium and vitamin D supplementation, particularly whilst on bisphosphonates
Surgery is rarely required for fractures, severe deformity or arthritis
Monitoring involves check the serum alkaline phosphatase (ALP) and reviewing symptoms. Effective treatment should normalise the ALP and eliminate symptoms.
Complications of Paget’s
Two key complications to remember are:
Osteogenic sarcoma (osteosarcoma)
Spinal stenosis and spinal cord compression
