Anatomy of the Hip
A bursa is a small sac of fluid that acts as a cushion between bones and the overlying soft tissues, reducing friction between the bone and muscles. There are four bursae associated with the hip. One, the trochanteric bursa, overlies the greater trochanter, which is the bony point of the hip that serves as a point of attachment for many of the muscles that move the hip joint. This is the largest bursa of the hip and the most common to cause symptoms. Another, called the iliopsoas bursa, is located on the groin side of the hip and lies between the bone the and iliopsoas tendon. The ischiogluteal, or simply ischial, bursa is deep in the pelvis below the hip joint and overlies the ischium of the pelvis. The gluteus medius bursa is near the trochanteric bursa and lies between the femur and the gluteus medius tendon. When any of these bursae become irritated and inflamed, the condition is commonly referred to as hip bursitis.