Diagnostic ultrasound ( PDFDrive )

1922 PART V Pediatric Sonography
Indications for Hip Ultrasound 8
Abnormal indings on physical or imaging examination of
the hip
Monitoring of patients with development dysplasia of the
hip (DDH) treated with a Pavlik harness or other splint
device
Any family history of DDH
Breech presentation regardless of gender
Oligohydramnios and other uterine causes of postural
molding
Neuromuscular conditions
Dynamic Sonographic Technique: Normal
and Pathologic Anatomy
History
he irst in-depth use of sonography was performed by Graf, 23
an Austrian orthopedic surgeon. Scanning was performed from
the lateral approach with the femur in its anatomic position.
Graf ’s method, which keyed on acetabular morphology, established
ultrasound’s ability to distinguish the cartilage, bone, and
sot tissue structures that compose the immature hip joint. When
real-time sonographic equipment became available, sonographers
experimented with diferent approaches to the hip 24 and the use
of dynamic assessment. Both approaches recognize the need for
critical landmarks of the femur and acetabulum. he dynamic
technique, as proposed by Harcke and colleagues, mirrored the
physical examination. 25
Although two basic assessment strategies evolved, morphologic
and dynamic, the two methods have common features, 25,26 in
addition to stressing positional relationships and stability and
assessment of critical acetabular landmarks. his formed the
basis for an examination drawing on elements from both techniques,
26,27 which has become part of the practice parameter
recommended by the American College of Radiology (ACR),
the American Institute of Ultrasound in Medicine (AIUM),
Society of Pediatric Radiology (SPR), and Society of Radiologists
in Ultrasound (SRU). 8
Technical Factors
Hip sonography should be performed with real-time linear array
transducers. One should use the highest frequency transducer
that provides adequate penetration of the sot tissues to the depth
required. For infants up to 6 months of age, the 15-8 MHz
broadband digital transducer is successful. A lower-frequency
transducer may be required for infants older than 6 months.
Standard scanning is performed from the lateral or posterolateral
aspect of the hip, moving the hip from the neutral position
at rest to a position in which the hip is lexed. With the hip
lexed, the femur is moved through a range of abduction and
adduction, with stress views performed in the lexed position.
One aspect of hip sonography relevant to dynamic examinations
is the shit of the transducer between the examiner’s hands when
examining the right and let hip. he infant is lying supine with
the feet toward the sonographer. When examining the let hip,
Minimum Standard Examination for
Development Dysplasia of the Hip (DDH)
According to Guidelines From the American
College of Radiology (ACR), American
Institute of Ultrasound in Medicine (AIUM),
Society for Pediatric Radiology (SPR), and
Society of Radiologists in Ultrasound (SRU) a
• The minimum standard is two orthogonal planes: a
coronal view in the standard plane at rest (in lexion or
extension) and a transverse view of the lexed hip with
and without stress. This enables an assessment of hip
position, stability, 4 and morphology when the study is
correctly performed and interpreted. It should be noted
that additional views and maneuvers can be obtained
and that these may enhance the conidence of the
examiner.
• Morphology is assessed at rest. The stress maneuvers
follow those prescribed in the clinical examination of
the hip and assess femoral stability.
• The attempts to dislocate the femoral head or reduce a
displaced head are analogous to the Barlow and
Ortolani tests used in the clinical examination. It is
acceptable to perform the standard examination with
the infant in a supine or lateral position. 8
a Modiied from ACR-AIUM-SPR-SRU practice parameter for the
performance of the ultrasound examination for detection and
assessment of developmental dysplasia of the hip. American College
of Radiology. 2013. Available from: https://www.acr.org/~/media/ACR/
Documents/PGTS/guidelines/US_Hip_Dysplasia.pdf. Accessed
2/21/2017. 8
the sonographer grasps the infant’s let leg with the let hand,
and the transducer is held in the right hand. When the right hip
is examined, we recommend that the sonographer hold the
transducer in the let hand and use the right hand to manipulate
the infant’s right leg. Although some sonographers ind this
awkward at irst, ambidexterity in this context is easily mastered.
We found that this technique makes it possible to perform the
stress maneuver more reliably and better maintain the planes of
interest.
For a satisfactory examination, the infant should be relaxed.
Infants can be fed before or during the examination. Toys and
other devices to attract the infant’s attention are helpful and can
be used as sonography is being performed. A parent can hold
the infant’s arms or head and can talk to the infant. here is no
need for sedation. he upper body may remain clothed. Our
standard practice is to leave the infant diapered and expose only
the side of the hip being examined (strongly recommended for
boys).
he anatomy is considered in orthogonal views. It is our
routine practice to record images in each of these views for
permanent records. his standardizes the examination and, in
our institution, provides a guideline for the technologist who
performs the initial examination. In describing views, we use a