Paget's disease
Paget's disease is the most common form of bone inflammation, or osteitis. The bones become weakened, soft and abnormally enlarged. Any part of the skeleton can be affected, but the most common sites include the skull, spine, pelvis, thigh bone, shin and the bone of the upper arm.
Paget's disease tends to affect people over the age of 40 years, with around three per cent of this age group affected. The rate increases to about 10 per cent in people over 80 years of age. It affects men and women equally. The cause of Paget's disease is not yet fully understood. Some theories suggest people with a genetic predisposition to the disorder may become infected with an unidentified virus, which then triggers the bone abnormalities.
Paget's name is also given to a skin disease, which is usually associated with an underlying cancer.