Pes Anserine Bursitis is a common cause of anterior knee pain that occurs when the anserine bursa (sub muscular bursa) becomes inflamed. Bursae are fluid-filled jelly-like sacs that act as cushions and decrease friction between tendons and their attachments to bone. If the bursae become inflamed, then there is an increased fluid and increased pressure on the knee-tendon. The bursae and tendon become painful, known as bursitis.
The pes anserine bursa or “goose foot” (latin) is a bursa on the inside of the knee 2-3 inches below the knee. When is bursa becomes irritated and painful, it’s known as pes anserine bursitis.
Pes anserine bursitis palpation
Knee pain or swelling on the pes anserinus 2-3 inches down the knee on the skin may feel “boggy” when compressed by fingers. The pes anserine may show redness and feel warm to the touch. Pain increases with activities that involve loaded knee extension, such as climbing stairs or hill running.