What are the important measurements on hip ultrasound of the neonate?

The alpha angle is used most commonly as a measurement of acetabular concavity, and it is calculated as the angle between the baseline and the roof line. A normal alpha angle is 60⁰or greater. Angles of 50⁰ to 60⁰ may be physiologically typical in the immediate neonatal period, but hips with these angles are considered immature and require clinical and ultrasound follow-up. Angles of less than 50⁰ are always considered abnormal and require treatment.
The beta angle is measured between the baseline and the inclination line. It is not in common use.