could you help clarify normal ER in infants? In your MSK developmental study guide, it states ~100 degree range, but in Campbell’s p.106, it talks about ER being 30 degrees due to cumulative effects of anteversion & antetorsion? Thanks!
If you were to assess the full passive range of motion of a neonate’s hips, the external rotation would be 90 degree or greater. The resting posture of the hip within the joint is ~30 degrees of external rotation due to anteversion (60 degrees) being greater than antetorsion (30 degrees) at birth. The 100 degrees of external rotation is related to PROM of the hip joint and the 30 degrees of external rotation is related to the position of the head of the femur in the acetabulum.