Housemaid knee is an inflammation of:

Prepatellar's bursitis is called "housemaids knee" or miner's kneePrepatellar bursitisIt is a common cause of swelling and pain above the patellaIt is due to inflammation of the prepatellar bursa.This structure is a superficial bursa with a thin synol lining located between the skin and the patella.The bursa develops within the first years of life as a result of mechanical pressure and friction, and it serves the purpose of reducing friction on underlying structures and allowing maximal range of motion in the knee.Aseptic prepatellar bursitis is commonly caused by repetitive work in a kneeling position, hence the name "housemaid's knee".Infrapatellar bursitis/clergyman's kneeIt is the inflammation of the infrapatellar bursa, which is located just below the patella.It is often called "clergyman's knee" due to its historical frequency amongst clergyman, who injured the bursa by kneeling on hard surfaces during prayer.