Prepatellar bursitis, sometimes called 'water on the knee' or 'housemaid's knee¹', is an extremely painful condition. But what is it? What are its causes? And how may it be treated?

What is it?

Just in front of the kneecap (the patella) lies a a small thin sac, filled with the body's natural lubricating fluid, called a bursa. This sac may become inflamed for a number of reasons, including repeated friction between the skin and the kneecap, injury, infection or an underlying inflammatory condition. This inflammation is known as bursitis.

Symptoms of the condition may include swelling and tenderness in front of the kneecap, the skin may appear red and hot, and movement of the joint and weight bearing may cause differing degrees of pain. Pain may be relieved when sitting, but aggravated when bending or kneeling.

Treatment

It is advisable to see a doctor as soon as possible if you have pain in your knees. If you have this condition, anti-inflammatory drugs are usually the first treatment prescribed. These may be tablets, or a gel to apply to the affected areas, and may include some pain relief. If anti-inflammatory treatment doesn't work, the doctor may wish to aspirate² the excess fluid from the bursa, or try to inject steroids into the site. In severe cases, surgical removal of the bursa may be necessary.

Other things that may help relieve the pain are: cold compresses, knee support bandages, over-the-counter creams such as Deep Heat and regular gentle movement to avoid stiffening in the joint.