Secondary osteoarthritis: What are the causes?

I'm 29 years old. I was diagnosed with osteoarthritis at age 23. What can you tell me about the cause of osteoarthritis in younger adults? Everything I read is about older adults.

- Donna / Indiana

Mayo Clinic rheumatologist April Chang-Miller, M.D., and colleagues answer select questions from readers.

Answer

In most cases, the cause of osteoarthritis isn't known. This is referred to as primary osteoarthritis. Primary osteoarthritis is most prevalent in middle-aged and older adults. When osteoarthritis occurs in younger adults, it may be due to an underlying condition. This is called secondary osteoarthritis. Causes of secondary osteoarthritis include:

Metabolic disorders that damage cartilage, such as hemochromatosis and ochronosis
Prior joint injury or surgery
Prior avascular necrosis, a temporary or permanent loss of blood supply to bone
Musculoskeletal and connective tissue disorders, such as Legg-Calve-Perthes disease and congenital hip dislocation
Hypermobility disorders, such as Ehlers-Danlos syndrome
Chronic joint inflammation, such as rheumatoid arthritis
Prior joint infection (septic arthritis)

Treatment of secondary osteoarthritis is directed at the underlying cause when possible. However, treatment may not repair joint damage from osteoarthritis.