Paget’s Disease of the Bone: A Brief Guide

Paget’s disease of the bone, while a frequent occurrence in Western countries, is still quite uncommon in India. Read on to learn what Paget’s disease is, how it occurs, and its diagnosis, treatment, complications, and prevention.

What is Paget’s disease of the bone?

Paget’s disease of the bone (or osteitis deformans) is a condition where the normal process of bone remodelling is disrupted, causing bones to become weak, brittle, and spongy. It most commonly affects the tibia (shin bone), although it can also affect the spine, hips, skull bone etc.

What happens in Paget’s disease?

Normal bones are living tissues that undergo constant breakdown and rebuilding, a process which is called ‘bone remodelling’. This process is irregular in Paget’s disease and the rate of old bone resorption and new bone formation is disproportional. While the exact cause behind this irregularity is unknown, one theory suggests that it can be due to abnormality in osteoclasts (cells that are responsible for breaking down old bone). This causes bones to become soft in the initial stages and, later, hard and dense.

What are the symptoms of Paget’s disease?

Most commonly, people with Paget’s disease experience –

Dull-aching pain in the affected bone
Bowing of the legs
Joint pain
Headache or loss of hearing (in case the skull is affected)
An increase in the size of your head (this can present as your cap or hat not fitting you anymore)
Pain, numbness or altered sensation in the limbs (in case of nerve compression)
Abdominal pain
Constipation
Generalised weakness and fatigue

What are the risk factors for Paget’s disease?

While the exact cause of Paget’s disease is unknown, risk factors include –

Age: Risk increases with old age
Gender: Men are affected more commonly than females
Genes: A positive family history increases your risk of developing the disease
Ethnicity: People living in Europe, USA and Australia are more likely to develop this condition; it is comparatively rare in Indians

How is Paget’s disease diagnosed?

Your doctor will take a detailed history of your symptoms and your family history, and then examine the affected areas. In case they suspect Paget’s disease, you will be asked to undergo the following tests –

Blood tests: These include serum calcium, serum phosphorous, parathyroid hormone, and alkaline phosphatase (ALP) levels. Usually, the latter will be raised while the other values are normal in Paget’s disease
X-ray: An X-ray can indicate fractures, bowing of the bones, enlargement of bones and other deformities
Bone scan: In this, a radioactive tracer is injected into your body through a vein. This tracer travels to various parts of the body and highlights areas with any kind of problems or abnormalities which can be seen on the scan

What’s the treatment for Paget’s disease?

Paget’s disease can be managed well with timely treatment. Most commonly drugs called bisphosphonates are given. These are commonly employed in conditions such as osteoporosis and osteopenia. They target osteoclasts (cells that are responsible for breaking down old bone), help slow down the rate of bone breakdown and reduce the risk of fractures and deformities.

In rare cases, surgery may be required. This is chiefly done in cases of fractures, severe deformities, advanced-stage arthritis, and in cases where the disease is affecting the spine (to relieve nerve compression).

What are the complications of Paget’s disease?

Possible complications of Paget’s disease include –

Fractures
Osteoarthritis
Kidney stones: This occurs due to excessive calcium in the blood, leading to calcium stones
Heart failure: The bones in Paget’s disease are more vascular (they receive more blood supply) compared to normal bones. Thus, the heart has to work harder in order to pump blood, which can eventually lead to heart failure
Permanent hearing loss
Loss of vision
Problems in the nervous system
Rarely it can lead to cancer

Can Paget’s disease be cured?

While Paget’s disease has no cure, timely diagnosis and treatment can help control the symptoms and prevent any complications that may occur if the condition goes untreated.

Can Paget’s disease be prevented?

Since the exact cause is unknown, Paget’s disease cannot be prevented. However, you can minimise the symptoms and complications of the disease by –

Getting adequate vitamin D and calcium in your diet
Reducing your risk of injuries and fractures by ensuring that your house is well-lit, wearing comfortable footwear, and installing handrails in the bathroom, toilet and around the house
Regularly following up with your doctor and taking your medications regularly

Is Paget’s disease related to cancer?

Paget’s disease of the bone has a small risk of cancer. Other types of Paget’s disease include –

Paget’s disease of the nipple, which is a type of invasive breast cancer that leads to patches over the nipple and surrounding area as well as crusting, eczema-like lesions, and other skin changes
Paget’s disease of the vulva, a type of ‘carcinoma in situ’ where the cells are abnormal and cancer-like but haven’t affected the other parts of the tissue yet. This condition is characterised by ulcer formation, redness, crusting, and a small risk of turning cancerous
Paget’s disease of the penis and scrotum, which chiefly affects older men and is accompanied by skin changes as well