- See:
DDH:
- Discussion:
- ultrasound allows description of the morphology of the acetabulum and the stability of the joint (dynamic examination);
- ultrasound becomes less useful after 6 months of age because of progressive ossification of the femoral head;
-
joint stability:
- femoral and acetabulum are evaluated while performing provative tests (Barlow maneuver);
- transducer is placed over the femoral head transverse to the pelvis while the hip is flexed and
a Barlow maneuver applied;
-
morphology:
- describes the cartilaginous and osseous anatomy of the acetabulum (noting depth and shape);
- Graf classification:
- coronal plane is imaged by placing the transducer over the lateral aspect of the hip;
- type I: normal hip:
- type II < 3 mo physiologic immaturity and > 3 mo mild dysplasia:
- type II hip is immature or mildly dysplastic and has a more shallow acetabulum with a round rim;
- in children younger than 3 months, most of these will spontaneously resolve;
- in children older than age 3 months, the deformity is expected to persist without treatment;
- type III: dislocation
- acetabulum is shallow;
- cartilaginous roof is displaced with eversion of labrum;
- type IV: high dislocation
- acetabular cup is flat and has the worse prognosis;
- femoral head is laterally and superiorly displaced;
- labrum is interposed between the femoral head and the lateral wall of the ilium;
Ultrasound screening for hips at risk in DDH.
RW Paton. et al.
JBJS. Vol 81-B. 1999. p 255.
Ultrasound imaging and secondary screening for congenital dislocation of the hip.
Boeree NR, Clarke NMP: J Bone Joint Surg Br 76B:525-533, 1994
Ultrasound screening of hips at risk for CDH: Failure to reduce the incidence of late cases.
Clarke NMP, Clegg J, Al-Chalabi AN: J Bone Joint Surg Br 71B:9-12, 1989
Real-time ultrasound in the diagnosis of congenital dislocation and dysplasia of the hip.
Clarke NMP, Harcke HT, McHugh P, et al: J Bone Joint Surg Br 67B:406-412, 1985
