Clinical History:
Correlative MR and US images of the same hip in the same patient with interval of 5 months (MRI done 5 months prior to the follow-up US). Anterolateral labrum shows a vertical tear on both US and MRI. Superior labrum shows a horizontal tear on US that was not evident on the previous MRI (? developed in interval between scans).
Imaging:
Diagnosis:
Acetabular labral tear
Discussion:
Ultrasound is not as sensitive as MRI for the detection of labral tears, and is prone to error if care is not taken to eliminate anisotropy and other artefacts. The presence of an associated peri or para-labral cyst (not seen in this example) is confirmatory.