Aetiology

Various aetiologies of labral tears have been proposed:

• trauma
  • traumatic tears are rare but can occur following a high or low velocity injury with or without subluxation or dislocation of the hip
• femoracetabular impingment
  • morphologic abnormalities affecting the acetabulum or the proximal femur, or both can result in FAI, which can crush the labrum on movement resulting in a labral tear
• capsular laxity
  • can lead to increased pressure on the anterosuperior labrum as the head moves anterior in the joint
• dysplasia
  • can cause localized anterior, posterior or diffuse tears as a result of increased stresses on the labrum because of the abnormal position of the femur within the acetabulum
• degeneration
  • a high percentage of labral abnormalities have been found in cadavers, suggesting degeneration with increasing age

Reference:

• Groh MM, Herrera J. A comprehensive review of hip labral tears. Curr Rev Musculoskelet Med 2009; 2: 105-17.
• Beaule PE, O'Neill M, Rakhra K. Acetabular labral tears. J Bone Joint Surg Am 2009; 91: 701-10.