Paget’s Disease: Symptoms, Causes, and Treatment
Paget’s disease is a chronic bone disorder that primarily affects older adults, causing pain, fractures, deformities, and nerve compression. It is characterized by abnormal bone remodeling, where bone growth becomes excessive and chronic disease disorganized, leading to changes in the density, size, and consistency of the affected bones. The pelvis, spine, skull, femur, and tibia are the most commonly affected areas. While many cases are asymptomatic, complications like fractures, deformities, and nerve entrapment can occur.
Understanding Paget’s Disease
In healthy bone, cells that break down old bone (osteoclasts) and cells that create new bone (osteoblasts) work in harmony to maintain bone strength and structure. In Paget’s disease, both osteoclasts and osteoblasts become overly active in specific areas, resulting in accelerated bone turnover. This rapid remodeling leads to enlarged bones with an abnormal structure, making them more fragile and prone to fractures.
The condition, also known as osteitis deformans due to the inflammation and deformation of bones, was first described by Sir James Paget, an English surgeon, in 1876. It is the third most common bone disorder in Western countries after osteoporosis and osteoarthritis. Its prevalence increases with age and is uncommon before age 40.
Symptoms and Complications
Paget’s disease is often mild, with many patients experiencing no symptoms or only mild bone and joint pain that can be managed with medication. However, complications can arise as the disease progresses. A rare but serious complication is the development of osteosarcoma, a malignant bone tumor. This occurs in about 1% of patients. If the pain becomes persistent and does not respond to medication, it is crucial to consult a doctor for reassessment.
Causes and Epidemiology
The exact cause of Paget’s disease is unknown, but some theories suggest a viral origin, as certain viral inclusions (such as paramyxovirus) have been found in the osteoclasts of affected individuals. The most widely accepted theory today points to a combination of genetic and environmental factors.
Paget’s disease is more common in individuals over 60 and is rare in those under 40. The prevalence is around 2.5% in men and 1.6% in women over 55, increasing to 6.9% in men and 5.8% in women over 85. It is slightly more prevalent in men than in women, and a family history of the disease is reported in about 40% of cases.
Geographically, Paget’s disease is more common in Western Europe (especially in England), the United States, Australia, and New Zealand, affecting approximately 1.5% to 3% of people over 65. It is much rarer in regions like Scandinavia, Central and South America, Japan, China, India, and Africa.
Common Symptoms of Paget’s Disease
Many people with Paget’s disease remain symptom-free for years, and the condition is often diagnosed incidentally through an X-ray or blood test done for another reason. The most common symptoms and signs include:
- Bone Pain: The most frequent symptom, characterized by a constant, burning sensation unrelated to movement.
- Joint Pain: Commonly affects the hip, shoulder, and knee joints, often leading to osteoarthritis and mobility issues over time.
- Spinal Cord Involvement: Conditions like kyphosis (excessive curvature of the spine), vertebral compression (where vertebrae collide due to cartilage loss), and significant spinal stiffness can occur.
- Bone Deformities: Weight-bearing bones in the lower extremities may deform, resulting in a “saber shin” appearance in the tibia or a “crook femur.”
- Enlargement of the Skull: Referred to medically as a “pagetic skull,” this can lead to an increase in head size.
- Headache: Often associated with the enlargement of the skull.
- Local Temperature Increase: In superficial bones like the tibia or skull, an increase in skin temperature can be observed due to the expansion of blood vessels in the affected area.
Paget’s disease requires careful monitoring and management to prevent and treat complications. If you or someone you know is experiencing symptoms or has been diagnosed with Paget’s disease, consult a healthcare professional for a comprehensive evaluation and personalized treatment plan.