Bursae are small fluid-filled sacs that are present between tense tendinous structures and bony prominences and serve to reduce friction between these structures.

There are multiple bursae around the knee joint. The pes anserine bursa, which is located between the tibia and three tendons of the hamstrings at the inside of the knee, is usually affected.

When the knee is overused or when there is more than the usual stress on the bursa, it can get inflamed, swollen and painful. This is called Bursitis. It is a common condition in athletes, particularly runners.

What are the causes for bursitis?

  • Meniscus tear
  • Incorrect training techniques
  • Tight hamstrings
  • Obesity
  • Osteoarthritis of the knee

How does a bursitis present?

Bursitis presents as a swelling, warmth and inflammation in the affected area. The most common location is 2-3 inches below the kneecap, in the location of the anserine bursa. Pain, usually, worsens with activity such as climbing stairs.

What is the treatment for bursitis?

Nonsurgical Treatment

Most cases of knee bursitis can be treated with rest, ice, compression, elevation and anti-inflammatory medications.


When a bursal swelling and pain doesn’t improve with the above treatment or gets infected, it may need drainage or excision through a small incision over the top of the swelling.