Bursitis. Joints and tendons are housed in a fluid-filled sac called bursae that works as a cushion during movement. Bursitis is a condition that results when the bursa becomes inflamed. An injury, infection or chronic inflammatory disease can cause bursitis and result in groin pain. Bursitis in the groin area can cause a person to favor one leg over another, resulting in knee pain on the opposite side from the groin pain. Doctors may prescribe an anti-inflammatory drug and suggest protecting and resting the area to allow for healing.