Knee Arthritis osteoarthritis of the knee degenerative joint disease of the knee
Knee arthritis is when the cartilage that caps the ends of the bones in the knee joint wears away or is damaged.  Without healthy, smooth cartilage, the bones begin to grind together.  This causes pain, swelling, and stiffness.
Knee arthritis is caused by wear and tear.  Cartilage does not have a very good blood supply and does not heal as well as other tissues.  Over time, it can begin to soften and peel away from the bone.  An injury to the knee can damage the cartilage and speed up the wear and tear.  Lifestyle, obesity, and genetics can play a role as well.
Knee pain usually gradually worsens over time.  However, sometimes an injury can aggravate arthritis that was already present.  Sometimes the knee swells (water on the knee).  Depending on what part of the knee is arthritic, it can hurt to do certain activities with the knee.  Typically, knee pain is worse with steps, getting up from a sitting position, and prolonged walking.
Knee arthritis is diagnosed based on a history, physical exam, and x-rays.  Patients usually have a history of gradually increasing pain that is worse with steps, getting up from a chair, or prolonged walking.  Sometimes knee pain begins with an injury because the injury aggravates arthritis that is already present.
During the physical exam, the knee is inspected for a deformity.  People who have severe arthritis sometimes develop a bowlegged deformity.  The knee may be very tender along the joint line.  Sometimes the knee swells (water on the knee).  Often the knee grinds and crunches as it is bent and extended.
In early arthritis, no changes are visible on an x-ray.  As arthritis becomes more advanced, the joint space between the bones narrows and bone spurs form.  X-rays are important when there is an injury in order to rule out fractures (broken bones).
Non-surgical treatments for knee arthritis are anti-inflammatory medications like ibuprofen, ice, elevation, and activity modification to include low impact exercise (swimming, water aerobics, etc).  Steroid injections can help to reduce pain and inflammation.  Physical therapy may or may not be beneficial.  Hyaluronate injections (rooster comb shots) are thought to help lubricate the knee and may be of benefit.
During knee arthroscopy (knee scope) damaged cartilage can be debrided or removed.  This often provides temporary relief and may be a good option for someone who is not responding to more conservative treatment but is not yet ready for a knee replacement.
The definitive treatment for knee arthritis is a knee replacement.  During a knee replacement, the arthritic ends of the bones in the knee joint are removed and replaced with metal implants.  Weightbearing is allowed immediately following surgery, but patients often need several weeks of rehabilitation.
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normal knee x-ray
degenerative changes (arthritis)
Knee Injection
Knee Arthroscopy
Knee Replacement Surgery