Developmental dysplasia of the hip: Clinical sciences

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Introduction0:00–1:00

Developmental dysplasia of the hip, or DDH for short, is a condition associated with misalignment of the femoral head and acetabulum, which results in an unstable joint.
Normally, the femoral head sits within the acetabulum, allowing both to grow together over the first few years of life to create a ball and socket joint.
But, when the acetabulum is too shallow, the femoral head is unable to stay in place, and both of these bony structures grow independently.
If this persists, eventually they will no longer fit together. It’s critical to screen all infants for DDH for early identification and treatment, as early treatment ensures better functional outcomes and reduces the risk of hip joint osteoarthritis.
Screening for DDH is often done during well-child visits via the hip exam, which differs based on whether the child is younger or older than 6 months.For infants under 6 months old, you should perform a thorough physical exam and check for any abnormalities on the hip exam using the Ortolani and Barlow maneuvers.

Less than 6 months1:00–1:51

Both maneuvers begin with the infant on their back with their hips flexed. The Ortolani maneuver involves slowly abducting the hip and then gently pressing upwards on the lateral thigh.
If the femoral head is dislocated, the Ortolani maneuver will push the femoral head up and into the acetabulum, making a “clunk.” This is also known as the Ortolani clunk.
On the other hand, the Barlow maneuver involves slowly adducting the hip and then gently pressing down on the knee. If there’s hip joint instability, the femoral head will be pushed down and out of the acetabulum, making a “click.” This is also called the Barlow click.

Normal hip exam1:51–3:01

If the infant’s hip exam is normal, meaning the Ortolani and Barlow maneuvers are negative, you should assess for DDH risk factors.
These include a family history of DDH, as well as breech orientation during pregnancy but after 34 weeks of gestation, regardless if an external cephalic version was successful.
If the infant has no risk factors, no further workup is needed, so you can continue with routine physical exam screenings at future well-child visits.
However, if DDH risk factors are present, you should order a bilateral hip ultrasound. If the ultrasound is normal, you can continue with routine physical exam screenings at future well-child checks.
On the flip side, if the screening ultrasound detects hip instability, asymmetry, subluxation, or even dislocation of the femoral head outside of the acetabulum, diagnose DDH.
Once you diagnose DDH, you should consult your surgery team, more specifically a pediatric orthopedist, who may recommend an abduction splint, like the Pavlik harness.Now let’s go back to the hip exam and discuss what to do if a patient has an abnormal hip exam, meaning a positive Ortolani or Barlow maneuver.

Abnormal hip exam3:01–3:32

In this case, you should immediately suspect DDH, and order a bilateral hip ultrasound. If the ultrasound detects hip instability, asymmetry, subluxation, or dislocation of the femoral head, diagnose DDH.
Just as before, you should consult your surgery team for an abduction splint, like the Pavlik harness.Now, let’s switch gears and discuss screening infants older than 6 months.

Older than 6 months3:32–5:34

First, you should perform a thorough hip exam and assess for abnormalities. Signs of DDH in older children include limited hip abduction, a thigh length discrepancy, or asymmetry of the thigh or gluteal skin folds.
If the infant is ambulatory, you could also observe an uneven gait while they are walking, which should also make you suspect DDH.
Now, here’s a clinical pearl! In some cases of DDH, the posterior dislocation of the femoral head can create the appearance of a shorter thigh segment, and a shorter leg overall.
This thigh length discrepancy is best appreciated by the Galeazzi test. To perform this test, place the infant on their back with their hips and knees flexed, so that their heels touch their bottom.
Then look at the height of the knees. If the knees are different heights, that means there’s a thigh length discrepancy, and the Galeazzi test is positive.
Once you suspect DDH, your next step is to order X-rays of the bilateral hips. If the imaging shows hip asymmetry and delayed ossification with subluxation or dislocation of the femoral head, you can diagnose DDH.
Again, consult your surgery team for further management, which typically varies by age. Infants between 6 months and 2 years old require closed reduction of the hip joint followed by abduction splinting, usually with a spica cast.
On the flip side, children who are older than 2 years require surgical open reduction of the hip joint followed by abduction splinting.And here’s one last clinical pearl!
After treatment, all children with DDH require routine X-rays of their hips to ensure proper development until they are skeletally mature.
This is also useful to screen for late complications of DDH repair, including osteonecrosis and osteoarthritis.Alright, as a quick recap… All children are screened for developmental dysplasia of the hip at their routine well-child visits, and your hip exam will help determine the next steps.

Review5:34–6:32

In infants under 6 months old, if the hip exam is normal, use DDH risk factors to determine whether to get a hip ultrasound.
However, if the hip exam is abnormal, meaning it reveals a positive Ortolani or Barlow maneuver, get a bilateral hip ultrasound to confirm the diagnosis.
Treatment involves an abduction splint, like the Pavlik harness. On the other hand, in infants over 6 months old, use your hip exam to determine if you need bilateral X-rays.
For treatment, infants between 6 months and 2 years old require closed reduction of the hip joint followed by abduction splinting, usually with a spica cast; while children older than 2 years need surgical open reduction followed by abduction