Anterior Sublabral Recess

The anterior sublabral recess of the hip joint is a normal anatomical variant characterized by a potential space or cleft at the interface between the acetabular labrum and the acetabular rim, most commonly located in the anteroinferior or anterosuperior quadrant of the acetabulum. This recess represents a partial, non-pathologic separation of the labrum from the acetabular cartilage, without extension into the substance of the labrum or through the full thickness of the labral base. It typically appears as a linear or crescentic area of contrast interposition on MR arthrography and should not be associated with abnormal labral signal, cartilage lesions, osseous abnormalities, or perilabral cysts, distinguishing it from a labral tear.