1. Ultrasound of the Infant Hip with Developmental Dysplasia
Harry H. Holdorf
PhD, MPA, RDMS, RVT

2. Objectives Identify normal vs. abnormal sonographic anatomy
Identify risk factors associated with DDH
Define the classifications of developmental dysplasia of the hip
Understand the use of hip angle measurement tools

3. Developmental dysplasia of the hip (DDH)
Developmental dysplasia of the hip ranges from mild acetabular dysplasia to irreducible dislocation of the femoral head
Ultrasound is an excellent method in the diagnosis of DDH

4. Congenital Hip Displacement

5. Developmental dysplasia of the hip (DDH) was formerly referred to as congenital dislocation of hip.
DDH is now the preferred term to reflect that DDH is an ongoing developmental process, which is variable in presentation and not always detectable at birth.
Developmental dysplasia of the hip refers to a spectrum of severity ranging from mild acetabular dysplasia with a stable hip, to more severe forms of dysplasia with neonatal hip instability, to established hip dysplasia with or without later subluxation or dislocation.

6. Epidemiology
Developmental dysplasia of the hip affects 1-3% of newborns and is responsible for 29% of primary hip replacements in people up to the age of 60 years.
The left hip is dislocated more often than the right and 20% of cases are bilateral.
It is more common in cultures that use swaddling of babies, forcing the hips into extension and adduction.

7. A breech presentation:
It has been reported that ultrasound screening seems to prevent many, but not all, operations for developmental hip dysplasia.
Selective ultrasound examination for babies with specific risk factors is recommended. An ultrasound examination of the hips should be performed if:  
There is a first degree family history of hip problems in early life, unless DDH has been definitely excluded in that relative.
A breech presentation:
at or after 36 completed weeks of pregnancy, irrespective of presentation at delivery or mode of delivery, or
at delivery if this is earlier than 36 weeks.
In the case of a multiple birth, if any of the babies falls into either of these categories, all babies in this pregnancy should have an ultrasound examination.

8. Risk Factors of DDH Female sex Family history (parental or sibling)
Breech Presentation
Multiple Gestations
Certain neuromuscular disorders i.e.: congenital torticollis
Oligohydramnios
Hip click (on clinical exam)
Club foot deformity
Asymmetric skin folds
High birth weight

9. History of diagnosing DDH
In the 1980’s Dr. Graf developed a technique using ultrasound to replace radiography to diagnose DDH.
Dr. Hacke introduced dynamic imaging to hip sonography in 1984.

10. Method Coronal View Baby in lateral Decubitis or supine position Flex knee 90 degrees Transducer parallel and lateral to hip Image should show femoral head centered in joint space. Ilium appears as straight line perpendicular to femoral head and parallel to transducer

11. Coronal View (Non-Stress

12. Coronal View (non-stress)
Includes the following anatomy
Ilium
Acetabular Rim
Femoral Head
Ischium
Labrum
Greater Trochanter

13. Anatomy (non Stress) Femoral Head Ilium Acetabular Rim
Greater Trochanter
Labrum

14. Method Continued Transverse view Infant in oblique position
Knee flexed 90 degrees
Rotate transducer 90 degrees from coronal
Femoral head should be centered on triradiate cartilage
Stress the hip in this view

15. Steps to Stress the HIP Flex hip 90 degrees Push the knee gently Posteriorly

16. Transverse View NON-STRESS Include: Femoral Shaft Greater Trochanter Ischium Femoral Head

17. Anatomy (Non-Stress Transverse)
Femoral Head
Ischium

18. Ultrasound of the new-born HIP
Birth to 4 months of age
High frequency linear transducer
Multiple focal zones
Output power at 100%
Feed baby during exam

19. Technique Continued… Decubitus position
Place a small rolled up towel behind the back.
Hip is flexed 90 degrees
Use both hands to stabilize the baby
Foot pedal

20. Angle Measurement Baseline Passes through plane of Ilium. Alpha Angle
Most common
Angle between baseline and roofline
Measures acetabular Concavity

21. Angle Measurement continued…
Beta Angle
Angle between baseline
And inclination line
Indicates acetabular roof
Coverage
Anything less than 55 degrees
is normal

22. Graf Classification

23. Graf Type 1 Covers femoral head Acetabular rim is angular
Labrum is in normal position
Hip angle measurement is greater than 60 degrees

24. Graf Type 1 Non Stress

25. Graf Type IIa Patients less than 3months of age
Femoral head is not displaced
Acetabular rim is rounded
Labrum in normal position
Hip angle measurement is between degrees
Repeat scan in 6-8 weeks

26. Graf Type IIa Non-Stress

27. Graf Type IIb Patients greater than 3 months of age
Femoral head is not displaced
Acetabular rim is rounded
Labrum is in normal position
Alpha angle is degrees
Orthopedic referral is suggested

28. Graf Type IIb (non stress)

29. Graf Type IIc Femoral head less than 50% covered Acetabular is rounded
Labrum is everted, more horizontally positioned
Alpha angle is degrees
Treatment and follow up suggested

30. Graf Type IIc

31. Graf Type IV non-stress
Femoral head is almost completely displaced
Acetabular rim is flattened
Labrum trapped between femoral head and ilium
Hip angle is less than 43 degrees
Requires urgent referral and treatment

32. Graf Type IV non-stress

33. Example 1: Normal Graf Type I

34. Example 2: Graf Type IV Femoral Head is displaced Acetabular rim is
Flattened
Labrum is Trapped

35. Conclusion
While newborn screening for DDH allows for early detection of this hip condition, starting treatment immediately after birth may be successful.
Many babies respond to the Pavlik harness, and/or casting. Additional surgeries may be necessary since the hip dislocation can reoccur as the child grows and develops.
If left untreated, differences in leg length or a duck-like gait, and a decrease in agility may occur.
In children 2 years or older with DDH, deformity of the hip and osteoarthritis may develop later in life. DDH can also lead to pain and osteoarthritis by early adulthood.

36. The technique of examining the infant hip joint with real-time ultrasound is widely accepted. Since the cartilaginous femoral head is clearly imaged by ultrasound, anatomical structures and their relationships can be accurately determined. Dislocated hips are easily detected and subluxations also can be visualized. The method of examination using real-time ultrasound is considered to be reliable, accurate, and a useful adjunct to radiography. The advantages are that it is non-invasive, portable, and involves no exposure to radiation.