Osteoarthritis (also known as OA) is the most common type of arthritis and one of the most common causes of knee pain. In the U.S. alone, more than 10 million people are estimated to have osteoarthritis in one or both knees.
What happens in knees with osteoarthritis
A healthy knee has cartilage and lubricating joint fluid — called synovial fluid — to protect and cushion the bones, allowing the knee to move and bend.
In knees with osteoarthritis, the cartilage protecting the ends of the bones gradually deteriorates, and the joint fluid loses its shock-absorbing qualities. Bones may begin to rub against each other, causing the common symptoms of knee osteoarthritis — pain, stiffness and loss of movement in the joint.
How knee osteoarthritis progresses
Doctors use two different sets of terminology to talk about the severity of osteoarthritis. Some may characterize osteoarthritis as grade 1 to 4. Other doctors may describe osteoarthritis as mild, moderate or severe.
Small osteophytes (a type of bone spur) and joint space narrowing may be present.
The surface of the cartilage in your knee joint begins to wear down. Symptoms are generally mild and may include occasional pain and brief morning stiffness.
Joint cartilage continues to wear away, and joint fluid may lose its ability to lubricate and cushion the knee. Bony growths, or spurs, may also form on the edges of the bones. Symptoms become more severe, and moving may become more painful.
Cartilage may totally wear away, causing bones to rub against each other. Pain may be more constant or more severe; your ability to perform day-to-day activities can diminish.
Keep in mind that the grade or stage of osteoarthritis and the level of pain aren’t necessarily connected. You can have mild osteoarthritis with considerable pain or severe osteoarthritis with little pain, so it’s important to discuss your pain in detail when talking to a doctor.
What can be done about knee osteoarthritis
Osteoarthritis of the knee is a chronic condition that typically develops slowly and gradually worsens over time. Though there is no cure for osteoarthritis, the symptoms are treatable, especially in the early stages of the disease.
If you have pain or stiffness in your knees, talk to your doctor to find out if you have osteoarthritis.
PLEASE NOTE: Photos taken and permission provided by Dr. Joseph J. Ruane, DO.