Paget’s disease involves which of the following bone-a) Pelvisb) Vertebraec) Skulld) Phalangese) Toes
**Core Concept**
Paget's disease is a chronic bone disorder characterized by an abnormal breakdown and regrowth of bone tissue, leading to deformities and an increased risk of fractures. This disease involves the osteoclasts, which are responsible for bone resorption, and the osteoblasts, which are responsible for bone formation.
**Why the Correct Answer is Right**
Paget's disease typically affects the bones of the pelvis, skull, spine, and long bones, such as the femur and humerus. The disease often starts in one of these areas and then spreads to other bones. The affected bones may become enlarged, deformed, and prone to fractures. In the skull, Paget's disease can lead to a characteristic "cotton wool" appearance on radiographs due to the thickened and disorganized bone.
**Why Each Wrong Option is Incorrect**
**Option A:** While Paget's disease can affect the pelvis, it is not the most commonly affected area.
**Option B:** Although Paget's disease can involve the vertebrae, it is not as characteristic of the disease as involvement of the skull.
**Option C:** The skull is a classic site for Paget's disease, which can lead to characteristic deformities and complications.
**Option D:** Paget's disease is not typically associated with the phalanges or toes.
**Clinical Pearl / High-Yield Fact**
Paget's disease can be distinguished from other bone disorders by its characteristic "cotton wool" appearance on radiographs, which is due to the thickened and disorganized bone.
**Correct Answer:** C. Skull.