Bursitis is caused by inflammation of a bursa, a small jelly-like sac that usually contains a small amount of fluid. Bursae are located throughout the body, most importantly around the shoulder, elbow, hip, knee, and heel. They act as cushions between bones and the overlying soft tissues, and help reduce friction between the gliding muscles and the bone.
The bony point of the hip is called the greater trochanter. It is an attachment point for muscles that move the hip joint. The trochanter has a fairly large bursa overlying it that occasionally becomes irritated, resulting in hip bursitis (trochanteric bursitis).
Another bursa located on the inside (groin side) of the hip is called the iliopsoas bursa. When this bursa becomes inflamed, the condition is also sometimes referred to as hip bursitis, but the pain is located in the groin area. This condition is not as common as trochanteric bursitis, but is treated in a similar manner.
The thighbone (femur) is the longest and the strongest bone in the body.
To break the thighbone takes a great deal of force, as might occur in a motor vehicle accident or a fall from a high place. Because of this, a broken thighbone is often associated with potentially life-threatening injuries to other body systems.