There is no doubt that acetabular labral tears are becoming increasingly common in sports medicine and rehab. It is unknown whether the incidence is on the rise from increased or changing patterns of activity or if we are simply better at finding these lesions with improvements in diagnostic imaging. It is likely a combination of each. Regardless, rehab professionals should be prepared with a solid rationale for intervention strategies when treating individuals with labral tears.
Acetabular labral tears are typically caused by trauma or developmental etiologies. The developmental causes often occur as linked to morphologic variance such as femoroacetabular impingment (FAI) and hip dysplasia. Frequent aggravating movements of the hip can also cause and accelerate labral degeneration.
The vast majority of labral tears in western society will occur in the anterior-superior margin with anterior translation of the head of the femur contributing to labral overload. The increased anterior translation of the femoral head occurs with excessive hip extension with standing or moving with hip hyperextension or in posterior pelvic tilt. Also remember that with external rotation we also get accessory anterior gliding. In individuals with excessive anteversion if they are to center the femoral head in the acetabulum, without compensatory tibial external rotation, they will walk with a degree of in-toeing. If they correct the in-toeing at the hip, the femur will be in a relatively externally rotated position with a propensity for increased anterior glide of the femoral head. On the other hand retroversion has been linked to labral tears as the retroverted femur will more likely impinge the anterosuperior labrum with flexion especially when combined with adduction. It is pertinent to assess femoral version. Craig’s test has been shown both valid and reliable for detecting femoral version (study, study.)
So with these considerations, here are some items to keep in mind when treating a patient with an anterosuperior acetabular labral tear.
- Do not stretch into hip extension! This should be pretty clear considering the location of injury and the mechanics associated with hip extension as mentioned above. Stretching into extension will only further irritate the anterior hip as the femoral head will slide anteriorly in this position.
- Strengthen (and pattern) the glute max without driving the hip into hyperextension. The glute max can help direct a posterior translation force on the proximal femur. The glute max should be trained with attention to end range position avoiding driving into hip (hyper)extension.
- Address any posterior pelvic tilt. As mentioned above posterior pelvic tilt can increase load to the anterior labrum. Examine for possible causes of posterior tilt especially tight/stiff hamstrings and/or abdominals and weak lumbar erectors and/or iliopsoas. The iliopsoas has been implicated by Lewis and Sahrman as a contributor to stabilization of the anterior hip during straight leg raise activity. Weakness/inactivity in this muscle as compared to the rectus femoris may be noted in those with anterior labral injury as the rectus femoris will tend to translate the femur forward while the iliopsoas was modeled to stabilize the anterior hip.
- Perform gait analysis. If an individual who has been determined to have increased anteversion walks with compensatory external rotation of the hip to walk with toes forward the femur will glide anteriorly. I would not recommend teaching gait in a toe-in position even with anteverted hips, however, any out-toeing beyond neutral should be corrected in these instances. Also assess for knee and hip hyperextension as marked by prolonged foot flat position late in stance phase.
- Limit isolated training of quadriceps and hamstrings, both of which can cause anterior translation of the femur.
- And finally good guiding principles of rehab are to simply avoid aggravating positions, strengthen joints and surrounding areas outside of the painful positions, and gradually reintroduce required and acceptable movements as tolerated by the patient.
For a good read on the topic see Shirley Sahrmann and Cara Lewis’s paper on the topic of labral tears.