When the cartilage in your knee wears away — a condition that increases with age
Knee osteoarthritis is a condition where the cartilage inside the knee joint gradually wears down, causing pain and stiffness.
Cartilage acts as a cushion between the bones. As we age, it slowly deteriorates and thins out.
It is most common in middle-aged and older adults, and approximately 25 million people in Japan are affected.
Over time, cartilage loses its elasticity and becomes more prone to wearing away
Excess weight increases load on the knee; bow-legs or knock-knees concentrate stress unevenly
Without the cushion, bones rub together, leading to pain and swelling
As the disease progresses, the shape of the joint changes and movement becomes limited
With consistent strengthening exercises and weight management, many patients experience pain relief and slower progression. If conservative treatment is not enough, surgical options such as total knee replacement or osteotomy may be considered.
When Surgery May Be Considered
If conservative treatments have been thoroughly tried but pain persists and daily life is significantly affected, total knee replacement or osteotomy may be discussed. The timing and approach are carefully determined based on each patient's condition.
This may not be your arthritis getting worse.
If the knee suddenly swells and becomes red and hot, or if you have a fever, the cause may be an infection or gout/pseudogout rather than worsening osteoarthritis. Please see a doctor promptly.