Developmental dysplasia of the hip (DDH) is an important newborn-related topic. A 2016 report gave new updates that highlighted the “primary goal of preventing and/or detecting a dislocated hip by 6 to 12 months of age in an otherwise healthy child, understanding that no screening program has eliminated late development or presentation of a dislocated hip and that the diagnosis and treatment of milder forms of hip dysplasia remain controversial.”
Materials for this week:
- Case and discussion
- Evaluation and Referral for Developmental Dysplasia of the Hip AAP Clinical Report 2016
- Developmental Dysplasia of the Hip – Pediatrics in Review article 2012 (see really helpful figures in this article)
- Helpful videos: Video of Ortolani and Barlow; hip-safe swaddling technique and info about hip-safe carrying
- What are the primary risk factors for DDH? Female gender (up to 75% of DDH), family history, and breech position in the 3rd trimester. As of the updated guideline, there is now also a risk factor noted for tight swaddling with legs adducted and extended. As many as one in six newborn babies have mild hip instability at birth, and approximately one per thousand has a dislocated hip.
- How do we screen for and prevent DDH? All children should receive routine clinical evaluation of their hips at each scheduled health supervision visit. Based on consensus (due to the lack of clinical studies), children who have equivocal findings on exam, or increased risk factors for DDH (and normal exam findings) should have imaging. Hip-safe swaddling allows the legs to move into flexed and abducted hip position (i.e., legs not confined to a straight extended position). Safe baby carrying is the “Spread Squat position” – also known as the M-Position, or Jockey Position – with the thighs spread around the mother’s torso and the hips bent so the knees are level with or slightly higher than the buttocks.
- What physical exam techniques should be used? Look for asymmetry* of the thigh or gluteal folds or limb length discrepancy while supine with the hips and knees in straight leg position, and then with the hips and knees in flexed position (*be aware if hip dysplasia is bilateral, we obviously can’t compare sides). Galeazzi sign is unequal knee height when legs are flexed. Use Ortolani maneuver (abduction movement to detect a dislocated femoral head reducing into the acetabulum), which the newest guidelines say has the best predictive value. Barlow manuever may not be necessary and/or harmful if too much pressure is applied. If Barlow is used, it should be gentle pressure applied while adducting the hip after performing Ortolani. The Ortolani and Barlow maneuvers are really most reliable in the first 6 weeks up to 12 weeks, as the hip laxity decreases with time. After that, we use observation of skin folds, hip movement, and leg length. Limited hip abduction or asymmetric hip abduction after the neonatal period (4 weeks) should be referred.
- What imaging do we use to screen? Ultrasound at age 6 weeks to 6 months, or plain x-rays at 4-6 months are considered fairly equivalent according to the data, and are implemented based on local availability of trained sonographers. Note, there are more false positives with early ultrasound, and many children with more subtle findings may be watched and rescreened.
- What constitutes a positive screen? Based on consensus, children who have unstable hips on exam (a “clunk” on Ortolani) or abnormal findings on radiographic evaluation, should be referred to an orthopedist. Isolated hip clicks without the sensation of instability usually represent normal laxity and myofascial tissue movement over the bones and do not require referral.