Osteoarthritis (OA) is the most common joint disease causing disability, affecting more than 7 million people in the United States. It is a degenerative joint disease characterized by the breakdown and loss of joint cartilage that is meant to cushion the joint. This causes the bones to rub together with movement, resulting in extreme pain at the joint.
The knee is the joint that is most commonly affected by OA. The knee joint is formed by the intersection of the femur (thigh bone) and the tibia (shin bone), with the patella (knee cap) sitting on top. In a normal functioning knee these bones are able to glide seamlessly against each other over a layer of cartilage that covers the ends of the bones. The cartilage protects the bones and allows them to glide smoothly with normal activity and acts as a shock absorber for high impact activity, like running or jumping. With knee OA, this cartilage begins to wear away. This results in pain, tenderness, stiffness of the joint (usually after periods of inactivity), lack of flexibility, a grinding sensation with movement, and sometimes bone spurs, which are small hard lumps felt around the joint.
What causes knee OA?
The most common cause of knee OA is age, as the ability of the cartilage to heal with injury decreases as a person gets older. Gender is also a factor, as women 55 and older are more likely to experience knee OA than men. Obesity, additionally puts an individual at risk of developing knee OA and is often a cause of OA’s further progression as the added body weight further increases the pressure on the joints. Heredity can also contribute to one’s likelihood of developing knee OA, including inherited abnormalities in the shape of the bones that make up and surround the knee.
Overuse and repetitive stress to any joint can also predispose people to knee OA. For example, people with certain occupations that include kneeling, squatting, or lifting heavy weights are more at risk for developing knee OA due to the constant pressure on the joint. The same goes for athletes, particularly in sports such as soccer and tennis, as the repetitive cutting can breakdown the cartilage, or long distance running due to the high impact of forces over an extended period of time.
With that said, it is important to note that regular moderate exercise strengthens the muscles surrounding the knee joint and can help decrease the risk of developing knee OA. In fact, there is a correlation between decreased quad strength and the disability and pain associated with knee OA.
Physical Therapy of Knee OA
Exercise has been proven to increase knee joint function and decrease symptoms of knee OA. Recent research suggests that physical therapy treatment of knee OA can reduce the need for knee surgery and steroid injections. The combination of strengthening exercises with manual therapy demonstrates improvements in motion, pain, and walking speed. Therapy programs should be designed specifically for each individual based on their particular impairments. For example, if you are lacking knee extension, meaning the ability to fully straighten your knee, both your exercises and manual therapy should focus on moving the joint in that direction. The same is true if you are lacking knee flexion and are unable to fully bend your knee. The problem may also be muscle tightness, in which case exercises should focus on stretching the muscles surrounding the knee. Following exercise it is always recommended to apply ice to the knee to decrease swelling and pain throughout the joint.
If conservative treatment such as physical therapy is unsuccessful in decreasing knee pain, there are other options to consider. Corticosteroid injections fight inflammation and can offer fast pain relief that may last several months. However, the benefits of injections are only temporary with a short term effect.
A more drastic option would be surgery. Arthroscopic surgery is a procedure where the surgeon can remove the damaged cartilage or any loose bone that may be causing pain in order to “clean up” the joint. This again can be seen as a short term solution in order to delay a more complex surgery, like a total knee replacement, which should be considered when all other options have failed. In this procedure, all or part of the knee joint is removed and replaced with an artificial joint made of metal and plastics. Though this surgery may take months to recover from, the relief can last years.
Physical therapy is a great place to start when experiencing knee pain. Surgery should only be considered if therapy is unsuccessful in reducing the pain caused by knee OA. It may be considered if the pain is severe and limits your everyday activities, if it persists while resting both during the day and at night, if you experience chronic swelling or if stiffness limits motion at the knee, causing inability to bend or straighten the knee. However, as previously stated, to prevent the need for knee surgery or to slow the progression of knee OA, regular moderate exercise is recommended. For more information on physical therapy services visit www.totalperformancept.com.