infant hip Flashcards
Bones, connective tissues and muscles originate from?
mesoderm
Hip bone composed of ?
- ilium
- ischium
- pubis
acetabulum?
- located at lateral aspects
- had triradiate cartilage
- creates articulation point for femoral head
At the rim of the acetabulum sits a lip of cartilage called?
acetabular labrum
femoral head at birth?
- catilaginous
- visible on u/s
when does hemoral head begin to ostify?
- 2-8 months of age
Maternal hormones contribute to?
the laxity of the fetal ligaments, which may in turn create vulnerable atmosphere for the hip to become subluxable or dislocatable
Developmental Dysplasia of the Hip occurs most frequently?
at birth
- may occur during infancy
cause of Developmental Dysplasia of the Hip?
- mechanical as a result of positional influences in utero and after birth
- physiological resulting from a response to maternal hormones in utero
Risk factors for DDH?
Born in breech position
Positive family Hx
Living in cultures that swaddle infants in extension and hip adduction
Oligohydramnios
Metatarsus adductus (img) and torticollis associated with DDH
Firstborn, female, white, high birth weight, native North American
DDH clinical assesment?
Clinical assessment of both hips done during routine neonatal screening
- Barlow maneuver
- Ortolani maneuver
- Visual assessment
result of DDH?
Most instabilities in hip joint will become normal without treatment
Significant dysplasias may lead to disability / hip replacement surgeries in adulthood
DDH barlow test?
Provocative test, determines if hip can be dislocated
The examiner attempts to push the femoral head posteriorly out of socket
Gentle adduction and push on the knee
DDH- ortolani test?
- The examiner attempts to reduce/relocate a recently dislocated hip
- Gentle out and up movement
If positive both tests produce a sensation of clunk
visual assessment of DDH
Positive Allis or Galeazzi sign:
- Relative shorteness of the femur with the hip and knees flexed
- Discrepancy in leg lengths
- Asymmetry of gluteal and thigh folds
- visual signs are useful only for unilateral DDH
Sonographic evaluation of hip?
Linear transducer
12- 7.5MHz for birth to 3 mo
5.0MHz for older infants
Sonography of the hip is best performed up to 6 mo of age
6months to a year, radiography is more reliable due to increasing bony ossification
Sonographic evaluation of hip imaging planes?
Coronal plane without stress
Transverse plane with and without stress maneuvers
Sonographic evaluation of hip positioning?
- supine or decube
coronal plane of the hip may be obtained how?
- May be obtained with the hip in a neutral (15-20o of flexion) or flexed position and the infant may be either in a decub or a supine
- probe placed at lateral aspect of hip providing a longitudinal image of hip from the coronal plane
what is seen in coronal scan place of hip?
The femoral head can be identified sitting in the acetabulum
Iliac line will be identified superiorly, and the bony shaft of the femoral neck will be identified inferiorly
Iliac line should appear as a straight line - important in making an accurate assessment