What is knee arthritis?
In a healthy knee, flexible connective tissue called cartilage coats the end of these bones and a thick liquid lubricates it. This allows for smooth, normal movement. In the arthritic joint, the cartilage has worn away and the joint surface has become rough and irregular. This prevents the joint from moving correctly. As the cartilage wears down, bone on bone rubbing occurs. This results in further damage, increased pain and bone spurs.
The knee joint is composed of three bones; the femur (thigh bone), the tibia (shin bone) and the patella (kneecap). Arthritis can occur in any of these areas. It can be caused by many factors including prior injury, genetics, some diseases such as rheumatoid arthritis, and excessive weight.
What causes knee arthritis?
Age is the most common cause of knee osteoarthritis, as the ability of cartilage to heal decreases as we get older. Most people will eventually develop some degree of osteoarthritis.
The following factors increase the risk of developing significant arthritis at an earlier age:
- Weight. Weight increases pressure on all the joints, especially the knees.
- Heredity. Some people are more apt to develop arthritis based on the shape of their bones around the knee.
- Gender. Women who are 55 and older are more likely than men to develop osteoarthritis of the knee.
- Repetitive stress injuries. People with jobs requiring a lot of kneeling, squatting, or lifting of heavy weights are at increased risk for knee osteoarthritis.
- Other illnesses. People with rheumatoid arthritis (a disease of the immune system that’s the second most common type of arthritis) are more likely to develop osteoarthritis. Other metabolic disorders, such as iron overload or excess growth hormone, also increase the risk of osteoarthritis.
What are the symptoms of knee arthritis?
Symptoms of osteoarthritis typically develop gradually and include:
- Pain and swelling
- Clicking or grinding sensation
- Decreased ability to move the joint
- Difficulty standing/walking for extended time periods
- Difficulty sitting for extended periods of time
- Difficulty getting out of a chair
How is osteoarthritis of the knee diagnosed?
Knee arthritis may be identified based on your medical history, your symptoms (such as the location of the pain), and the activities that make the pain better or worse. Your physician will also observe the movements and strength of your knee. If knee arthritis is suspected, an X-ray will typically confirm or deny the diagnosis.
How is knee arthritis treated?
The severity of your arthritis will determine the most appropriate course of action. For early-stage arthritis, physical therapy and anti-inflammatories can be effective treatment. In more advanced cases, the following can be effective at relieving your symptoms:
- Activity Modification: Patients with arthritis typically have to undergo some lifestyle modifications. If specific activities make your symptoms worse, then avoiding those activities can provide relief. Low-impact exercises such as cycling, elliptical, swimming, and light strength training are the best options.
- Anti-Inflammatory Medication: Oral anti-inflammatories may be effective at decreasing inflammation due to injury. However, some people suffer from side effects while taking them. If you experience anything unusual when taking these medications, contact your specialist immediately to determine if continued use is appropriate.
- Unloader Braces: Your specialist may prescribe an unloader brace. This brace acts to apply a force on the knee in such a way that the pressure on the worn area of the joint is relieved. You will need to wear this brace when participating in such activities as walking, hiking, etc. For some, this brace may provide significant symptomatic relief, allowing the enjoyment of physical activity again.
Steroid Injections: A steroid injection allows your specialist to place anti-inflammatory medication directly inside the joint. This can result in dramatic and potentially long-term relief of pain and swelling. If this does provide relief, you can safely have repeat injections done every three to four months without any harmful effects.
- Physical Therapy: Your specialist may prescribe several sessions with a physical therapist to increase your range of motion and strength, and to decrease your pain. After several visits, your therapist may recommend a home exercise program to help maintain any gains you have achieved during therapy.
- Joint Fluid Therapy: The only joint that the Food and Drug Administration has approved for this type of treatment is the knee. The medication is injected into the knee in three doses, typically spaced one week apart. The substance injected is hyaluronic acid, which helps to reduce friction between rough cartilage while cushioning the joint. This treatment can be done every six to nine months if your symptoms warrant it. Further information regarding this medication can be provided to you upon your request.
Ice is a convenient and inexpensive treatment option for knee pain. Placing a bag of ice directly on the knee for twenty minutes prevents swelling and inflammation from occurring inside the knee.
Finally, in the case of severe arthritis, surgery may be the best treatment option.
- Arthroscopy: In this scenario, the specialist will use a miniature video camera and tools to remove any loose cartilage. The result is a smooth joint surface free of loose tissue and minimal internal derangement that can cause irritation. This can provide significant relief and allow the joint to flow freely through its range of motion. Arthroscopy is useful in early arthritis or with internal derangement to treat problems that could lead to more severe arthritis down the road.
- Joint Replacement: In advanced cases of arthritis you may be a candidate for a total knee replacement. The techniques and prosthetics used in this surgery have made significant advances over the past decade. Patients who undergo a total joint replacement are living longer and getting more use out their new joint than ever before.
Meet the Expert: Doctor Bio Video Series
Did you know that a hip labral repair doesn’t always require surgery?
Ask the Expert: Regenerative Medicine Video Series