Paget's disease can cause complications such as:
- Osteoarthritis. Paget's disease can damage the bone around a joint. This can cause the cartilage in the joint to weaken and break down, which leads to arthritis. Many people feel bone or joint pain before they are diagnosed with Paget's disease and osteoarthritis.
- Broken bones (fractures). After a bone is weakened by Paget's disease, it can break easily. Even minor injuries can cause a complete break in a bone affected by Paget's disease.
- Fractures are most common in long bones or bones that hold up the weight of the body, such as the thighbone (femur), the forearm, or the back (spine). Broken long bones can be very serious and can lead to severe bleeding. Small breaks may cause pain that is made worse when you walk or you lift objects.
- Paget's disease may cause abnormal healing of a broken bone.
- Nervous system problems. Paget's disease can affect bone growth in the skull or spine, causing pressure on a nerve. Also, Paget's disease can damage the tiny bones in the ear, leading to hearing loss. Paget's disease can cause nerve problems such as:
- Hearing loss or ringing in the ears (tinnitus).
- Vision problems or blindness.
- Trouble walking or keeping your balance.
- Weakness and numbness in an arm or leg.
Rare complications of Paget's disease include:
- Heart failure. Bone tissue contains many blood vessels. Paget's disease causes increased blood flow to the bones, and sometimes it is difficult for the heart to keep up with the demand for increased blood flow. This can lead to heart failure.
- Bone cancer (osteogenic sarcoma). This is a rare but serious complication of Paget's disease. Severe bone pain and swelling of tissue around the bone are the most common symptoms of bone cancer.
People with Paget's disease often develop kidney stones and/or calcium deposits in blood vessels and heart valves. These problems are caused by increased calcium in the body from the faster-than-normal breakdown of bone tissue.