Paget's disease

Paget's disease of bone is a focal disorder of bone remodelling characterized by an increase in the number and size of osteoclasts in affected skeletal sites while the rest of the skeleton is spared.

Paget’s disease most commonly involves the axial skeleton, the pelvis being the most common, but it can affect any area. In the majority of patients, the disease affects at least two bones, but in one third of patients only one bone is affected. In the skull, the 8th nerve can be compressed, resulting in hearing loss. This is one of the more common complaints, being present in 37% of respondents in a recent survey of 2000 patients with Paget's disease . Other causes of hearing loss include pagetic involvement of the middle ear ossicles, which dampens the motion of these ossicles.

Unlike osteoarthritis, pagetic bone pain usually increases with rest, on weight bearing, when the limbs are warmed, and at night. An estimated 70% of patients who have Paget’s disease have no symptoms. The diagnosis is typically found incidentally on radiographs and laboratory investigations.

Fig 1: Osteoblasts and Osteoclasts

Fig 1: Paget's Disease of Bone

Fig 2: "Cotton Wool' appearance of Paget's Disease

Source: Fig 1, Fig 3,