Developmental dysplasia of the hip (DDH) is usually diagnosed by a physical examination. A medical history and other tests also may be useful in diagnosing DDH.

All babies are examined for DDH at birth. Newborns who have risk factors for DDH, such as having foot, knee, or leg deformities, are examined very closely for the condition.

If a newborn's thighbone (femur) feels loose, the health professional usually will apply a Pavlik harness to hold the bone in place.

Your child's hips are also examined during regular well-child checkups. But a baby with DDH who is older than 1 to 3 months may have fewer visible signs, making it more difficult to detect. These babies may have only slightly less mobility or flexibility of the affected hip joint(s).

Imaging tests to diagnose DDH

Tests that show images of the hip joint are often done to help diagnose DDH if results from physical examinations are unclear. These tests are also used to monitor treatments for DDH.

Imaging tests used to diagnose and monitor DDH include:

• Ultrasound of the hip. This test provides the clearest images in babies younger than 5 months when the hip joints are still made of cartilage. Ultrasound can provide images to help a doctor identify the subtle signs of DDH that often aren't detected during a physical examination.
• Hip X-rays. These tests are most useful after a child is 4 to 6 months old. Before this age, a baby's bones are too soft to show up well on an X-ray.
• CT scans. These tests are mostly used to help doctors monitor treatment for DDH.

An orthopedic surgeon or a pediatric orthopedist usually confirms a diagnosis of and provides treatment for DDH. Your health professional will refer you to one of these specialists if he or she suspects your child has DDH.