Hip Labral Tears

hip-labral-tearsThe socket of the hip joint is surrounded by a thick ring of dense fibrocartilage called the acetabular labrum. This is similar to the labrum in the shoulder. However, the function of the labrum in the hip is very different from that in the shoulder in that it does not provide additional stability to the hip joint. It serves to help lubricate the joint surface with synovial fluid. Tears of the acetabular labrum are becoming more commonly diagnosed because our ability to recognize the symptoms and imaging studies have both improved. Labral tears are more common in women than men (3:1 female to male).

MRI Arthrogram showing an anterior labral tear

Most patients presents with symptoms of intermittent sharp pain in the groin especially with deep flexion (knee to the chest) and sometimes have mechanical clicks or clunks in the hip joint. It is unusual for most people to recall an identifiable injury that caused the tear. In addition, patients often complain of increased pain after exercise. This is typically the next day rather than during exercise.

Possible locations of labral tears

The diagnosis is established with the use of a contrast enhanced MRI arthrogram, in which a small amount of contrast agent is injected into the hip joint prior to the MRI scan. Standard MRI scans have a very low positive predictive value in identifying labral tears and are not used routinely. The tear can be in various locations throughout the hip socket but anterior and superior tears are the most common.

Pincer type impingement with labral tear

Treatment of labral tears is controversial. In most cases the tear is caused by some type of mechanical impingement of the hip joint. Diagnosing the underlying mechanism is as important as treating the labral tear itself. Treating the labral tear without addressing the impingement will often lead to recurrent tears within a year or two.