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. In excessive weightlifting or running, the cause is usually attributed to extreme thickening of the tendons in the hip region. Snapping hip syndrome most often occurs in people who are 15 to 40 years old. Extra-articular
Extra-articular snapping hip syndrome is commonly associated with leg length difference (usually the long side is symptomatic), tightness in the iliotibial band (ITB) on the involved side, weakness in hip abductors and external rotators, poor lumbopelvic stability and abnormal foot mechanics (overpronation).
Popping during external snapping hip (lateral-extra articular), occurs when the thickened posterior aspect of the ITB or the anterior gluteus maximus rubs over the greater trochanter as the hip is extended. Internal snapping hip (medial-extra articular) is usually described by the patient as a snapping or locking of the hip with an audible snap and occurs when the iliopsoas tendon snaps over underlying bony prominences. Almost half of patients with internal snapping hip also have inter-articular pathology. Intra-articular
The causes of intra-articular snapping hip syndrome seem to be broadly similar to those of the extra-articular type, but often include an underlying mechanical problem in the lower extremity. The pain associated with the internal variety tends to be more intense and therefore more debilitating than with the external variety. Intra-articular snapping hip syndrome is often indicative of injury such as a torn acetabular labrum, ligamentum teres tears, loose bodies, articular cartilage damage, or synovial chondromatosis (cartilage formations in the synovial membrane of the joint). Diagnostic
Ultrasound during hip motion may visualize tendon subluxation and any accompanying bursitis when evaluating for iliopsoas involvement in medial extra-articular cases. MRI can sometimes identify intra-articular causes of snapping hip syndrome. Treatment
This condition is usually curable with appropriate treatment, or sometimes it heals spontaneously. If it is painless, there is little cause for concern.