Degenerative Joint Disease (Osteoarthritis)
The knee is the largest and strongest joint in your body. It is made up of the lower end of the femur (thighbone), the upper end of the tibia (shinbone), and the patella (kneecap). The ends of the three bones where they touch are covered with articular cartilage, a smooth, slippery substance that protects and cushions the bones as you bend and straighten your knee.
Two wedge-shaped pieces of cartilage called meniscus act as “shock absorbers” between your thighbone and shinbone. They are tough and rubbery to help cushion the joint and keep it stable.
The knee joint is surrounded by a thin lining called the synovial membrane. This membrane releases a fluid that lubricates the cartilage and reduces friction.
Cause & Symptoms
Cause
Osteoarthritis
Osteoarthritis is the most common form of arthritis in the knee. It is a degenerative,”wear-and-tear” type of arthritis that occurs most often in people 50 years of age and older, but may occur in younger people, too.
In osteoarthritis, the cartilage in the knee joint gradually wears away. As the cartilage wears away, it becomes frayed and rough, and the protective space between the bones decreases. This can result in bone rubbing on bone, and produce painful bone spurs.
Osteoarthritis usually develops slowly and the pain it causes worsens over time.
Symptoms
A knee joint affected by arthritis may be painful and inflamed. Generally, the pain develops gradually over time, although sudden onset is also possible.
There are other symptoms, as well:
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The joint may become stiff and swollen, making it difficult to bend and straighten the knee.
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Pain and swelling may be worse in the morning, or after sitting or resting.
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Vigorous activity may cause pain to flare up.
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Loose fragments of cartilage and other tissue can interfere with the smooth motion of joints. The knee may “lock” or “stick” during movement. It may creak, click, snap or make a grinding noise (crepitus).
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Pain may cause a feeling of weakness or buckling in the knee.
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Many people with arthritis note increased joint pain with rainy weather.
Diagnosis
During your appointment, your doctor will talk with you about your symptoms and medical history, conduct a physical examination, and possibly order diagnostic tests, such as x-rays or blood tests.
Physical Examination
During the physical examination, your doctor will look for:
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Joint swelling, warmth, or redness
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Tenderness about the knee
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Range of passive (assisted) and active (self-directed) motion
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Instability of the joint
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Crepitus (a grating sensation inside the joint) with movement
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Pain when weight is placed on the knee
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Problems with your gait (the way you walk)
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Any signs of injury to the muscles, tendons, and ligaments surrounding the knee
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Involvement of other joints (a possible indication of rheumatoid arthritis)
Imaging Tests
X-rays
These imaging tests create detailed pictures of dense structures, like bone. They can help distinguish among various forms of arthritis. X-rays of an arthritic knee may show a narrowing of the joint space, changes in the bone and the formation of bone spurs (osteophytes).
Other tests
Occasionally, a magnetic resonance imaging (MRI) scan, a computed tomography (CT) scan, or a bone scan may be needed to determine the condition of the bone and soft tissues of your knee.
Laboratory Tests
Your doctor may also recommend blood tests to determine which type of arthritis you have. With some types of arthritis, including rheumatoid arthritis, blood tests will help with a proper diagnosis.
Your Providers
Great Lakes Physical Therapy
| The Physical Therapy team at Great Lakes Orthopedics offer a wide range of programs and specialized services to help our patients restore and maintain their physical strength, performance skills, and levels of function. Our well-trained, professional staff utilize the most progressive treatment options and techniques to ensure the best possible recoveries. |
Treatment Options
Treatment
There is no cure for arthritis but there are a number of treatments that may help relieve the pain and disability it can cause.
Nonsurgical Treatment
As with other arthritic conditions, initial treatment of arthritis of the knee is nonsurgical. Your doctor may recommend a range of treatment options.
Lifestyle modifications. Some changes in your daily life can protect your knee joint and slow the progress of arthritis.
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Minimize activities that aggravate the condition, such as climbing stairs.
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Switching from high impact activities (like jogging or tennis) to lower impact activities (like swimming or cycling) will put less stress on your knee.
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Losing weight can reduce stress on the knee joint, resulting in less pain and increased function.
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Physical therapy. Specific exercises can help increase range of motion and flexibility, as well as help strengthen the muscles in your leg. Your doctor or a physical therapist can help develop an individualized exercise program that meets your needs and lifestyle.