Q: I have knee bursitis. What is bursitis? What can I do to relieve my discomfort?
A: A bursa is a sac-like structure that sits over large joints such as the knee or hip joints. Bursae act as cushions between muscle and bone and reduce friction during movement.
When a bursa becomes painful or inflamed, the condition is called bursitis. The symptoms of knee bursitis include pain made worse by movement of the knee, but which is still present even when the knee is not moving.
There often is swelling of the area above the kneecap (the patella). Finally, if you push on the area where you feel pain, you'll feel tenderness.
The knee has several bursae. The bursa that lies directly over the kneecap (called the prepatellar bursa) and the bursa located just below the knee joint, toward the inside (the anserine bursa) are the most likely to cause pain.
Sometimes, bursitis develops from a disease that can affect joints, such as gout or rheumatoid arthritis. Sometimes a bacterial infection carried in the blood finds its way into the bursa and causes an infection (not just an inflammation). This is rare compared to the more common causes of knee bursitis.
The common causes of knee bursitis are overuse or prolonged kneeling. Knee bursitis used to be called "housemaid's knee" because it was a common affliction. Carpet layers and baseball catchers are two other professions afflicted by knee bursitis. But often bursitis develops for no apparent reason.
During the healing process, which usually lasts two to six weeks, you'll need to avoid activities that aggravate your bursitis.
If you have prepatellar bursitis and can't avoid resting on your knee, use a kneeling pad as a cushion. If you have anserine bursitis, sleep with a small pillow between your thighs so that the other knee does not rest its weight on the sore knee at night.
In the meantime, try RICE (rest, ice, compression and elevation) to reduce swelling. You can take acetaminophen (Tylenol) or an anti-inflammatory drug such as aspirin or ibuprofen (Advil, Motrin, others) to relieve discomfort and reduce inflammation.
If the pain is intense or does not quickly improve, your doctor may inject a corticosteroid drug directly into the area. However, repeated steroid injections can damage the tissue in your knee.
Your doctor may also recommend physical therapy to strengthen and stretch your thigh muscles, which help to protect your knees. (I've put descriptions and illustrations of two strengthening exercises on my website, AskDoctorK.com.)
After your bursitis heals, take these preventive measures to prevent a recurrence:
• Get up and stretch your legs regularly if you work on your knees for long periods of time.
• Stretch your legs before and after you exercise.
• Vary your workouts to rest your knees.
• Elevate and ice your knees after you exercise or spend a long time on your knees.
• Try over-the-counter arch supports in your shoes.
• Dr. Komaroff is a physician and professor at Harvard Medical School. To send questions, go to AskDoctorK.com.