Housemaid's Knee (Prepatellar Septic Bursitis).

An 83-year-old Japanese tatami craftsman with underlying diabetes mellites who complained of severe pain and feeling of warmth in his right knee, with mild chills. Fluid accumulation was seen in his prepatellar bursa and Staphylococcus aureus was detected in his synovial fluid culture, confirming the diagnosis of prepatellar septic bursitis. Prepatellar bursitis is well known as housemaid's knee, which is caused by inflammation of the prepatellar bursa among people who spend long periods of time kneeling such as housemaids, clergy, and gardeners.