Hip Ultrasound

Doctors order a hip ultrasound when they suspect a problem called "progressive hip dysplasia" (DEC). Evolutionary hip dysplasia is a malformation that can occur before, during, or weeks or months after birth.

The probability of developing progressive hip dysplasia increases in the following circumstances:

- Pregnancies where the fetus is compressed within the uterus (due to a reduction in the amount of amniotic fluid or "oligohydramnios")
- Abnormal position of the baby inside the womb (when it comes from the breech)
- Babies with a family history of progressive hip dysplasia

Likewise, developmental hip dysplasia occurs more frequently in girls than in boys and in first-borns.

Doctors will take all of these factors into account when deciding whether to evaluate a baby's hip using ultrasound. In addition, the baby will undergo an ultrasound if the doctor detects any abnormalities in the hip during the physical exam, such as the following:

- At birth, inability to move the thigh out from the hip as far as is usually possible
- The doctor notices a clicking sound or hears a "click" when moving the baby's thigh outward during the routine exam
- Difference in length or appearance between the baby's legs