Figure 13.

Pathomechanisms of acetabular labral tears. A) Hip dysplasia: subluxation of the femoral head results in “inside-out” tears the hypertrophied labrum from the acetabular rim together with a sleeve of cartilage. Typically, this results in an intrasubstance labral tear. B) Impingement: dynamic abutment of the femur against the acetabular rim as seen with femoroacetabular impingement. Typically, this is results in an intersubstance tear. C) Levering out: femoral torsional abnormality resulting in impingement against the ischium. Typically, this results in an intrasubstance tear