Presentation
Pain at right hip during full range of hip movements.
Patient Data
Non-arthrographic MRI images acquired of the pelvis with bilateral hip joints show mildly flattened femoral head contours with slender gracile femoral necks. Also seen is mild uncovering of femoral heads relative to the acetabular cup on coronal images. Axial images reveal an anterior paralabral cyst at the right acetabulum.
The non-arthrographic oblique axial MR imaging of right hip reveals a complete anterior acetabular labral tear with labro-osseous separation and a 2.0 cm paralabral lobulated cyst.
Case Discussion
This case is a young female with no history of high impact sport activity, giving history of exceedingly difficult full range of hip movements, particularly painful on right side. In our experience, the femoral head and acetabular contour conforms to subtle developmentally dysplastic hip morphology. These individuals due to nonobvious symptoms and signs escape detection in early years and later develop labral injuries secondary to wear and tear at the hip during late adolescence to young adulthood. As seen above partly uncovered femoral heads (which is described as an extrusion index by some authors), are accompanied by a full-thickness anterior labral tear and a paralabral cyst at the right acetabulum.
Very infrequently a tear or small paralabral cyst, like this, may be confused with a normal prelabral sulcus or recess at the articular labral margin, which is usually quite sharply marginated and along only one-third or rarely one-half the thickness of the labrum.
In this case, the findings were confirmed on arthroscopy.