Hip Ultrasonography

Hip ultrasonography (USG) is a safe, effective, and painless imaging method used to examine the hip joints of infants suspected of having developmental dysplasia of the hip (DDH). This technique provides clear imaging of the soft tissues and cartilage structures of the joint, which have not yet fully ossified, enabling early diagnosis and treatment.

After performing hip USG, the alpha and beta angles are measured for classification using the Graf Method, which is the standard classification system for developmental dysplasia of the hip:

Hip USG Classification According to the Graf Method

• Type I: Normal hip. The alpha angle is greater than 60°. The cartilage/bone structure of the hip is normal.
• Type II: Developing or mildly immature hip. The alpha angle is below 60°.
  • Type II-a: If the alpha angle is below 60° in infants younger than 3 months, it is considered physiological immaturity and does not require treatment but should be monitored.
  • Type II-b: If the alpha angle remains below 60° after 3 months, it is classified as Type II-b, which requires immediate treatment.
• Type III: There is a subluxation (partial dislocation). The femoral head (the head of the thigh bone) does not fit properly into the acetabulum (hip socket). If not corrected with early intervention, it may lead to permanent joint problems.
• Type IV: Complete dislocation (luxation). The femoral head is entirely displaced from the acetabulum, and urgent treatment planning is necessary.

Importance and Advantages

• Unlike X-rays, ultrasound does not use ionizing radiation, making it safe and suitable for repeated use.
• The procedure is quick and does not cause pain or discomfort to the baby.
• When diagnosed early, DDH can be easily treated without surgery using devices such as the Pavlik harness or Tübingen orthosis.
• Early detection with hip USG is crucial in DDH treatment, allowing timely initiation of appropriate treatment options to prevent future complications such as hip pain and walking disorders.