Mod 4-1 Paget's Disease Flashcards
Who described all forms of Paget’s disease?
Sir James Paget
Paget’s disease is the most common what?
Chronic metabolic disease
What else has Paget’s disease been known as? Why?
Osteitis deforming because the disease is characterized by localized widespread distortion or deformity of the architecture of affected bone(s) caused by an increased remodeling of bone by osteoblasts and osteoclasts.
What happens in the early stages of Paget’s disease?
Bone is rapidly resorbed (seen as lucency) and replaced with bone of a coarse, irregular consistency (seen as sclerosis) that become weak and fractures easily.
What is the etiology of Paget’s disease?
Unknown but appears to have hereditary component as well as some link to a measles-related antigen.
What are the two forms of Paget’s disease?
Monostotic (one bone) and Polyostotic (many bones)
When Paget’s disease affects one bone (monostotic) what bone is most commonly affected?
The tibia
What form of Paget’s disease is most common?
Polyostotic
In polyostotic Paget’s disease, what sites re usually the first affected?
Pelvis and weight bearing bones of the lower extremity.
List Paget’s disease site examples.
Pelvis, long bones of lower extremity, skull, vertebrae, clavicles and ribs.
How does skeletal Paget’s disease progress?
In phases, most commonly 2 phase process.
What occurs in Phase 1 of Paget’s disease?
- A large amount of blood is shunted to the affected bone and the bone becomes softened and volume is lost as bone mass is reabsorbed.
- Considered the destructive phase
- W/o the strengthening effect of osteoblastic activity, the bone(s) weaken and weight bearing structures may bow.
What occurs in phase 2 of Paget’s disease?
- Repairative phase
- The bone becomes dense as sclerosis predominates, new bone is brittle with thickened/enlarged appearance, fractures may occur
What do the symptoms of Paget’s disease depend on?
- Site of lesions
- Severity of lesions
What percentage of patients with Paget’s disease have no symptoms?
20%
Lesions that are located where seem to cause the most difficulty in Paget’s disease?
Long bones
What can happen in an advanced case of Paget’s disease?
The weakened bone may fracture with even a slight blow or vertebral collapse.
What is the most common presenting symptom of Paget’s disease?
Pain
List clinical manifestations of Paget’s disease
- Pain (most common)
- Pathologic fractures
- Headache
- Tinnitus
What is osteoporosis circumscripta?
refers to discrete radiolucent regions of the skull on plain radiographs
What happens to the skull as sclerosis increases?
Enlarges
As the cranium softens, expands and becomes heavier what else happens to the cervical area?
Bears down on cervical vertebrae, depressing the brainstem putting pressure on the cranial nerves leading to hearing loss and lightheadness and may eventaully lead to the collapse of C1 which leads to compression of the spinal cord and neural deficits.
What fraction of paget’s disease cases affect the pelvis?
2/3
What part of the pelvis is often affected?
The pubis and ischium and will show some degree of enlargement
What does the book say about the pelvis in Paget’s disease?
It is often the initial site of Paget’s with the iliac rim of the pelvic brim (superior and medial to the acetabulum) to be the first bony areas affected.
How does the destructive phase of Paget’s disease progress in the long bones?
Begins at one articular end and progresses towards teh other end creating a “blade of grass” appearance.
When only one lesion is present with Paget’s disease, it’s commonly seen in the ______ area. What form of Paget’s disease is this?
Tibial; monostatic
Describe phase 1 of Paget’s disease
- Areas of destruction (lucency)
- Lucency seen as osteoporosis circumscripta
- “Blade of grass” appearance in long bones
Describe phase II of paget’s disease
- Areas of sclerosis (dense new bone)
- Thickening
- Repairative phase
- Cortex develops coarser, trabecular pattern
- Structure enlarges as new bone is laid down
- Patchy pattern of sclerosis appears when cranium is involved called “cotton wool” pattern
What happens as bone weakens in Paget’s disease?
- Pathologic fractures
- Bowing (deformation)
What is the effect on radiographic technique?
- Depends on phase of disease
- Osteoporosis is destructive
- Sclerosis is additive
