Snapping hip syndrome, also referred to as dancer's hip, is a medical condition characterized by a snapping sensation felt when the hip is flexed and extended. This may be accompanied by a snapping or popping noise and pain or discomfort. Pain often decreases with rest and diminished activity. Snapping hip syndrome is commonly classified by the location of the snapping as either extra- articular or intra-articular. Symptoms In some cases, an audible snapping or popping noise as the tendon at the hip flexor crease moves from flexion (knee toward waist) to extension (knee down and hip joint straightened). It can be painless. After extended exercise, pain or discomfort may be present caused by inflammation of the iliopsoas bursae. Pain often decreases with rest and diminished activity. Symptoms usually last months or years without treatment and can be very painful. Extra-articular Lateral extra articular The more common lateral extra-articular type of snapping hip syndrome occurs when the iliotibial band, tensor fasciae latae, or gluteus medius tendon slides back and forth across the greater trochanter. This normal action becomes a snapping hip syndrome when one of these connective tissue bands thickens and catches with motion. The underlying bursa may also become inflamed, causing a painful external snapping hip syndrome. Medial extra-articular Less commonly, the iliopsoas tendon catches on the anterior inferior iliac spine, the lesser trochanter, or the iliopectineal ridge during hip extension, as the tendon moves from an anterior lateral (front, side) to a posterior medial (back, middle) position. With overuse, the resultant friction may eventually cause painful symptoms, resulting in muscle trauma, bursitis, or inflammation in the area. Intra-articular Because the iliopsoas or hip flexor crosses directly over the anterior superior labrum of the hip, an intra-articular hip derangement (i.e. labral tears, hip impingement, loose bodies) can lead to an effusion that subsequently produces internal snapping hip symptoms. Causes The causes of snapping hip syndrome are not fully understood. The onset is often insidious with reports of a "non-painful" sensation or audible snapping, clicking, or popping with certain activities. Individuals often ignore the "snapping" sensation, which may lead to future discomfort with activity. Athletes appear to have an increased risk of snapping hip syndrome due to repetitive and physically demanding movements. Among athletes such as ballet dancers, gymnasts, horse riders, track and field athletes and soccer players, military training, or any vigorous exerciser, repeated hip flexion can lead to injury.