Housemaid’s knee is also known as prepatellar bursitis. It is caused by inflammation of the bursa (a small fluid-filled sac) in front of the kneecap. It more commonly occurs in people who spend long periods of time kneeling. Housemaid’s knee is more common in tradesmen who spend long periods of time kneeling -for example, carpet fitters, concrete finishers and roofers. In sports medicine, this injury is common in wrestlers, who get it from their knees rubbing on the mats.
Any age group can be affected by housemaid’s knee. It is generally more common in males than in females. Housemaid’s knee in children is more likely to be caused by infection. Infection is also a common cause of housemaid’s knee in people whose immune systems are not working normally; people include those receiving steroid treatment or those on chemotherapy treatment for cancer.
What is bursitis?
Bursitis means inflammation within a bursa. A bursa is a small sac of fluid with a thin lining. There are a number of bursae in the body. Bursae are normally found around joints and in places where ligaments and tendons pass over bones. They can also be found in other places if there has been unusual pressure or friction placed on that area.
Generally, the function of a bursa is to help reduce friction and allow maximum range of motion around joints. When there is inflammation within a bursa (bursitis), the bursa swells due to an increase in the amount of fluid within the bursa sac.
What is housemaid’s knee?
There are four bursae located around the knee joint. They are all prone to inflammation, or bursitis. However, the prepatellar bursa (the bursa in between the skin and the kneecap) is most commonly affected. Its position is shown in the diagram. Housemaid’s knee is the name given to inflammation of the prepatellar bursa.
What causes housemaid’s knee?
There are a number of different things that can cause housemaid’s knee:
· A sudden, one-off, injury to the knee – For example, a fall or direct blow on to the knee
· Recurrent minor injury to the knee – This usually happens after spending long periods of time kneeling down, putting pressure on the kneecap (patella). Historically, this was typical of housemaids who spent long periods of time on their knees scrubbing floors; hence, the term housemaid’s knee.
· Infection – The fluid in the prepatellar bursa sac can become infected and cause inflammation within a bursa (bursitis). This is particularly common in children with housemaid’s knee. This usually follows a cut, scratch or injury to the skin on the surface of the knee. This injury allows germs (bacteria) to spread infection into the bursa.
· Another inflammatory disease – If you already have an inflammatory disease such as rheumatoid arthritis, you have an increased risk of developing a bursitis. Rheumatoid arthritis is a form of arthritis that causes inflammation, pain and swelling of joints.
· Gout – If you have gout or pseudogout, you have an increased risk of developing a bursitis. Gout is caused by a build-up of uric acid crystals. Uric acid is a chemical in the blood that is usually harmless and passed out with the urine. In gout, it builds up and collects within a joint, causing pain, inflammation and joint swelling.
How is housemaid’s knee diagnosed?
Dr. Stickney is usually able to diagnose housemaid’s knee simply by examining your knee. He may ask you questions about your occupation or if you have had any recent knee injury and if you have any history of other joint problems.
If Dr. Stickney suspects that housemaid’s knee is caused by infection, he may suggest that they draw some fluid from the bursa. This is a straightforward procedure. The skin on the front of your knee is sterilized with some fluid and the procedure is carried out in a clean environment. A small needle is used to take a sample of the fluid from your prepatellar bursa, which is directly underneath the skin in front of your kneecap. This fluid is sent off to the laboratory to look for signs of infection. If infection is confirmed, the laboratory may be able to suggest which antibiotic medicines will treat it.
Treatment options for Housmaid’s Knee
Episodes’ of housemaid’s knee will settle with medical or supportive treatment unless infected, in which case, your Dr. Stickney may draw fluid, send for lab tests and prescribe some form of antibiotics. Drug or surgical treatment is determined in the treatment plan if the injury is recurring and/or infection is extreme.
If you are suffering from housemaid’s knee, call Dr. Stickney and schedule an appointment at 425-823-400 or email him at ProOrthoAppointment@proliancesurgeons.com.