Bursae in the knee may become swollen and inflamed as a result of an injury such as a blow to the front or side of the knee.  Wear and tear – particularly kneeling on hard surfaces – may also cause swelling, along with conditions such as arthritis, gout and infection.  There are different types of knee bursitis:  Prepatellar bursitis (housemaid’s knee)  Prepatellar bursitis is commonly known as housemaid’s knee and is the irritation of the thin bursa in between the kneecap and the skin. It’s most often caused by kneeling and is seen in carpet layers, plumbers or gardeners. It can also be caused by a direct blow to the front of the knee – and is common in contact sports.  Baker’s cyst  Also called a popliteal cyst, this is the swelling of the bursa at the back of the knee joint. It can be caused by a blow to the knee or other conditions such as arthritis and gout.