Bursas of the knee (401/1700)

A 12yo boy presents with painful swollen knew after a sudden fall. Which bursa is most likely to
be affected?

a. Semimembranous bursa
b. Prepatellar bursa
c. Pretibial bursa
d. Suprapatetaller bursa


































answer: C

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. 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.