Bursitis is inflammation of a bursa sac. Over 150 bursae are in the body. Most bursae are present at birth, but some come into existence in sites of repetitive pressure. Common areas where bursitis can occur include the elbow, knee, and hip. Different types of bursitis include traumatic, infectious, and gouty.
Traumatic bursitis is the type involved with repetitive motion injuries.
Traumatic bursitis is most common in people younger than 35 years. When the body is unable to repair the tears in the tissue as fast as they are being made, inflammation occurs, leading to the sensation of pain. Tendinitis is made worse by active motion of the inflamed tendon. The skin overlying the inflamed tendon may be red and warm to the touch. The painful spot is usually in the groove where the arm meets the shoulder.