Recent Developments in Ultrasound Diagnostics in relation to Breech Births:
Ultrasound is suggested for:
- 2 to 6 week old infant with questionable examination, especially first-born girls
- 6 week-old with family history of hip dysplasia even when the exam is normal
- 6 week-old girl who was in the breech position even when the exam is normal
- Consider an ultrasound for 6 week-old boys who were in breech position even when the exam is normal
American Academy of Pediatrics (AAP) has guidelines for detection of hip dysplasia. These screening guidelines are dependent on the use of history, physical exam, and imaging. AAP recommends all newborns should be examined at birth for developmental dysplasia of the hip. If the exam shows instability, then referral or treatment is recommended. The hip examination is repeated at 2-4 weeks of age. An ultrasound study or referral to orthopedics is recommended when that examination is suspicious for hip dysplasia. When the hip examination is normal, then risk factors are considered. Some of the most important risk factors are positive family history of hip dysplasia and breech position in the womb. The AAP suggests that an ultrasound study at six weeks of age or an x-ray of the pelvis at 4 months of age is warranted when there is a positive family history of hip dysplasia and also for girls who were in the breech position. Even boys have a high risk for dysplasia after breech birth so imaging studies may be useful for those infants too. A recent study out of Rady Children’s hospital in San Diego questions whether the current screening practices are sufficient for babies who were in the breech position. They found that 29% of breech babies with a normal ultrasound at six weeks developed mild hip dysplasia by 4-6 months of age. The study recommended that all breech birth babies have an X-ray of the pelvis at six months of age as a possible method to reduce the risk of developing late DDH in this group of patients.
“Imrie, Meghan, Scott, Vanessa, Stearns, Philip., “Is ultrasound screening for DDH in babies born breech sufficient?”Journal of Child Orthopedics (2010) 4:3-8”
Committee on Quality Improvement, Subcommittee on Developmental Dysplasia of the hip,. American Academy of Pediatrics (2000) Clinical practice guideline: early detection of developmental dysplasia of the hip. Pediatrics 105: 896-905
Adolescent Peri-Acetabular Osteotomy (PAO)
17 year old boy with painful left hip. Note large dysplastic acetabulum and femoral head subluxation on the patient’s left side. The head of the femur is moving in a false socket high on the side of the pelvis. The arthrogram below shows that the hip can be put back into the true socket.
During the arthrogram shown below, radiographic dye is injected into the hip joint. The dark area is fluid that is filling the joint space. In the first image the hip is abducted and internally rotated to demonstrate that the femoral head slides lower into the socket leaving fluid above the hip joint. The second image shows where the femoral head sits when the thigh is in neutral position as it is during standing. This is the position of the hip during the first x-ray above. It was determined that PAO might be possible to place the intact joint surface in a better position to support the femoral head during weight-bearing. The PAO will rotate the socket so that it is more on top of the femoral head.
The x-ray below shows the hip after PAO. Note that slope of the socket is more horizontal and the intact portion of the acetabulum has been rotated so that it is directly over the femoral head. This allows the intact cartilage surfaces to support weight-bearing. The patient was relieved of pain and should be able to avoid total joint replacement for many years.