Magnetic resonance arthrographic classification of labral tears
| Stage 0 | Labra have homogeneous low signal intensity, a triangular shape, and a continuous attachment to the lateral margins of the acetabulum without a notch or a sulcus. There is a recess between the joint capsule and the labrum, a so-called labral recessus, which consists of a linear collection of the contrast material extending between the cranial margin of the acetabular labrum and the joint capsule |
| Stage 1A | Labra have an area of increased signal intensity in the centre which does not extend to the margins, a triangular shape, and a continuous attachment to the lateral margin of the acetabulum without the sulcus. A normal labral recessus is also present |
| Stage 1B | Labra are similar to stage 1A except that they are thickened and no labral recessus is present |
| Stage 2A | There is an extension of contrast material into the labra without detachment from the acetabulum; they are triangular and have a labral recessus |
| Stage 2B | Same as stage 2A except that they are thickened and the labral recessus is not present |
| Stage 3A | Labra are detached from the acetabulum but are triangular in shape |
| Stage 3B | Labra are thickened and detached from the acetabulum |