From the Guidelines
Ultrasound screening for Developmental Dysplasia of the Hip (DDH) is indicated for infants with risk factors, such as breech presentation, positive family history of DDH in first-degree relatives, and clinical findings like hip instability or limited hip abduction, as well as for those with abnormal physical examination findings. The primary indications for ultrasound screening include:
- Breech presentation during the third trimester
- Positive family history of DDH in first-degree relatives
- Clinical findings such as hip instability, limited hip abduction, or asymmetric skin folds
- Female infants, who have a higher risk and may warrant screening, particularly when combined with other risk factors
According to the most recent and highest quality study, ultrasound is typically performed between 4-6 weeks of age 1, as earlier scans may detect physiologic immaturity that resolves spontaneously. For breech infants, screening is recommended even after normal physical examinations due to their significantly increased risk. Ultrasound is preferred over radiographs in infants under 4-6 months of age because it can visualize the cartilaginous components of the hip that aren't visible on X-rays, and it avoids radiation exposure. The examination assesses hip morphology and stability, allowing for early intervention when necessary to prevent long-term complications such as early-onset osteoarthritis, gait abnormalities, and chronic pain. Selective ultrasound screening can identify DDH in children at high risk for DDH and negative physical examination findings, as supported by studies 1.
From the Research
Indications for Ultrasound in Developmental Dysplasia of the Hip (DDH)
The following are indications for ultrasound in DDH:
- Persistent clinical or sonographic dislocatability or dislocation 2
- Major dysplasia or minor dysplasia combined with an unstable femoral head 2
- Sonographically immature or minor dysplastic but stable hips that do not show improvement 2
- Infants with risk factors such as breech position or positive family history 3
- Infants with clinically unstable hips or dislocated hips 2, 3
Ultrasound Techniques and Screening Programs
Different ultrasound techniques are used for screening, including:
- Graf method: a quantitative classification system 4, 3
- Harcke method: a qualitative definition 4
- Terjesen method: a combination of quantitative and qualitative descriptions 4
- Suzuki method: a qualitative definition 4 Screening programs vary across European countries, with some using universal screening and others using selective screening based on risk factors 3
Age-Related Indications
- Infants under 6 months: ultrasound is the preferred imaging modality 3
- Infants over 6 months: X-ray or MRI may be used in addition to ultrasound 5, 6
- 6-month-old infants: ultrasound can be used as an alternative to X-ray for diagnosing DDH 6
Diagnostic Accuracy
The diagnostic accuracy of ultrasound in DDH is high, especially when combined with other imaging modalities such as MRI and X-ray 5