Understanding Paget’s Disease of Bone

It was a routine day at the clinic when Peter, a retired architect in his late 60s, came in for a check-up. He was a regular patient, always diligent about his health. However, today he seemed more anxious than usual.

“Doctor Priya,” Peter began, “I’ve been feeling this deep, dull ache in my hips and legs, especially at night. I thought it was just old age creeping in, but the pain seems to be getting worse. I even noticed my gait has changed—I seem to be walking with a bit of a waddle.”

After a detailed discussion and examination, I suspected that Peter might be dealing with Paget’s disease of bone—a condition not widely known but more common than people realize. It’s a disorder where the normal bone maintenance process is disrupted, leading to weakened and misshapen bones.

What is Paget’s Disease of Bone?

Paget’s disease of bone is a chronic condition affecting the skeletal system. In a healthy body, bone tissue is continually broken down and replaced with new bone tissue—a process called bone remodeling. However, in Paget’s disease, this process becomes disorganized. The bone breaks down faster than it should, and the new bone that forms is softer, weaker, and more prone to deformities.

The exact cause of Paget’s disease remains unknown, but it’s believed that both genetic and environmental factors play a role. Some studies suggest a possible viral trigger.

Peter listened intently as I explained the condition. “Is it common?” he asked.

“Yes,” I replied. “In Western countries, it’s estimated that about 1 in 10 people over the age of 80 have Paget’s disease. It’s more prevalent in certain populations, such as those of Anglo-Saxon descent.”

How Common is Paget’s Disease and Who Gets It?

While Paget’s disease is relatively rare in people under the age of 40, its prevalence increases with age. It’s twice as common in men as in women and tends to cluster in families, suggesting a hereditary component.

Certain populations are more affected by Paget’s disease, particularly those of Northern European descent. The condition is less common in Asian and African populations.

Research Insight: A study published in The Lancet found that individuals with a family history of Paget’s disease are at a higher risk of developing the condition. The study emphasized the importance of genetic predisposition in the disease’s onset.

Which Bones are Affected?

Paget’s disease can affect any bone in the body, but it most commonly targets:

• Pelvis
• Femur (thigh bone)
• Tibia (shin bone)
• Vertebrae (spinal bones)
• Skull
• Humerus (upper arm bone)
• Clavicle (collar bone)

The affected bones may become enlarged, misshapen, and structurally weak. This can lead to complications such as fractures, arthritis in nearby joints, and nerve compression.

Peter pointed to his hip. “So this ache could be because my hip bone is affected?”

“Exactly,” I confirmed. “Paget’s disease often presents as a deep, dull ache, especially in weight-bearing bones like the pelvis and femur.”

What are the Symptoms?

Interestingly, many people with Paget’s disease remain asymptomatic and are only diagnosed incidentally through X-rays or blood tests done for unrelated reasons. When symptoms do occur, they can include:

• Bone pain: Usually a deep, dull ache that worsens at night.
• Joint pain and stiffness: Particularly in the hips and knees.
• Deformities: Bowed legs or an enlarged skull.
• Hearing loss: If the skull is affected, it can lead to nerve compression and hearing impairment.

Peter nodded. “I’ve noticed some hearing difficulties recently. Could that be related?”

“It’s possible,” I replied. “If the bones in your skull are affected, they can press on the auditory nerves, leading to hearing issues.”

What are the Signs?

Paget’s disease doesn’t always present with obvious signs, but some noticeable changes include:

• Bowed legs
• Enlarged skull
• Waddling gait
• Warmth over the affected area

The increased blood flow to the affected bones can cause the skin over those areas to feel warm.

Research Insight: A study in Bone journal highlighted that increased vascularity in affected bones is a hallmark of Paget’s disease, contributing to the warmth felt over the affected areas.

What are the Risks?

If left untreated, Paget’s disease can lead to several complications:

• Fractures: The weakened bones are more prone to breaks.
• Arthritis: The abnormal bone shapes can put extra stress on joints, leading to arthritis.
• Nerve compression: Enlarged bones can press on nearby nerves, causing pain, tingling, or numbness.
• Hearing loss: Due to skull involvement.
• Heart problems: In rare cases, the increased blood flow required by affected bones can strain the heart.

Who Should Be Treated?

Not everyone with Paget’s disease requires treatment. Asymptomatic individuals may not need intervention, but those with symptoms or at risk of complications should receive medical care.

Generally, treatment is recommended for:

• Relatively young patients
• Those with symptoms, especially in the legs and spine

What is the Treatment for Paget’s Disease?

The goal of treatment is to manage symptoms, prevent complications, and improve quality of life.

General Measures

• Healthy diet: Ensure adequate intake of calcium and vitamin D to support bone health.
• Regular exercise: Gentle weight-bearing exercises can help maintain bone strength.
• Pain management: Over-the-counter painkillers like paracetamol can help relieve bone pain.

Medication

In the past, there were limited options for treating Paget’s disease. However, modern medicine offers effective solutions:

• Bisphosphonates: These drugs slow down bone breakdown, helping to regulate the bone remodeling process. They can be taken orally or through injections.
  • Examples include alendronate, risedronate, and zoledronic acid.
• Calcitonin: A hormone that helps regulate bone metabolism, though it’s less commonly used today.

Research Insight: A review in Osteoporosis International found that bisphosphonates significantly reduce bone turnover and improve bone density in patients with Paget’s disease.

Surgical Intervention

In severe cases, surgery may be necessary to:

• Correct bone deformities
• Relieve nerve compression
• Replace damaged joints

FAQs About Paget’s Disease of Bone