neonatal/msk exam review guide

why ICH common in preterm infants

low birth weight

<34 wks

fragile & not developed blood vessels

US appearance of ganglion cyst

cystic (simple) on wrist

when does ant. fontanelle close

9-15 mnths

another name for mastoid fontanelle

posterolateral fontanelle

where is largest part of choroid plexus located

lateral ventricle

leukomalacia definition

CNS dysfunction bc hypoxic ischemia or infection

white matter softens

leukomalacia presents…

limp & pale at birth

seizures

hypotonia

poor prognosis

neurological deficits

IVH grade 0

no hemorrhage

IVH grade I

(SEH) blood only in germinal matrix

IVH grade II

(w/out dilation) SEH breaks thru ependymal into ventricle

IVH grade III

(w/ dilation) motor problems & mental retardation

3 segments of the brain

cerebrum

cerebellum

brain stem

most common neonatal congenital infection

cytomegalovirus cmv

hydrocephalus

dilation of ventricle bc CSF obstruction

SAG neonatal head

corpus collosum

4th ventricle

cavum septum pellucidum (anechoic)

3rd ventricle

cerebellum

COR neonatal head image

frontal horns of lateral ventricle *always in image*

sylvian fissure (bright spot)

cavum septum pellucidum

what lumbosacral anomaly is indication for neonatal spine US

sacral dimple/pilonidal sinus

skin anomalies (hair, dimple, pigment)

until when is spinal US helpful on newborns

<6 mnths bc post. spinous process not yet ossified

US appearance of spinal canal

anechoic

spinal dysraphism

inadequate neural tube fusion

open-spinal dysraphism (neural tissue exposed to skin)

closed-spinal dysraphism (neural tissue covered by skin)

myelocele

myelomeningocele

OSD

herniated meninges

herniated meninges & nerve roots

tethered cord

CSD

low, thick filum terminal; below L3

diastomyelia

CSD

seperation of spinal cord into two; thoracolumbar

dorsal dermal sinus

CSD

thin, epithelial tract from skin to spinal canal; deep midline dimple

sacral dimple/pilonidal sinus

CSD

m.c. reason for neonatal spinal US; dimple w/ tract

spinal lipoma

CSD

fat & connective tissue connected w/ spinal cord; skin covered back mass; lumbar

terminal myelocystocele

CSD

skin covered, fluid filled, lumbar mass; CSF accumulation; omphalocele

where does conus medullaris terminate when tethered

L3 or below

transducer for neonatal spine

8-15 mhz; high frequency; linear/sector

where does diastomyelia occur

thoracolumbar

dorsal dermal sinus

thin, epithelial lined tract that passes from skin to spinal canal; CSD; lumbosacral; deep midline dimple

most common methods for DDH

clinical assessment

sonography

types of hip displacement

instability

subluxation

dislocation

normal value of hip displacement

alpha >60°

scanning planes for femoral head

COR, neutral: how well femoral head is in acetabulum (>50%)

COR, flexion: same as COR but hold hip at 90°; w/ stress

TRANS, flexion: rotate probe 90°; flexed femur at 90°; w/ stress (look for ‘U’)

hip effusion

swelling of hip joint bc increased synovial fluid around joint

pain, limping, no weight bearing, fever

DDH risk factors

breech

family history

cultural swaddle

abnormal physical

female

1st pregnancy

oligohydramnios in utero

high birth weight

bursa definition

closed connective & synovial sacs w small amount of fluid

what does bursa do

gliding at high friction points

bursa US appearance

small, hypoechoic, flat sac; hyperechoic wall; fluid

most common joint injury

ankle (complex diarthrosis joint)

plantar fasciitis

inflammation of plantar fascia (>4mm)

thick, medial, central, & lateral cords

msk image

skin

fat

muscle

tendon

what shares insertion point with supraspinatus at tendon

infraspinatus

what is elevated with rotator cuff imaging

subscapular nerves (C5, C6, C7)

suprascapular nerves (C4, C5, C6)

minor rotator cuff tear criteria

subdeltoid bursal effusion

major rotator cuff tear criteria

focal, nonvisualized cuff

localized absence of cuff

abnormal echogenicity

periosteum US appearance

thin, bright line parallel to cortex of bone

tendons

bone to muscle

flexion & extension

type II collagen & water

ligaments

bone to bone

stability & strength

type I collagen & water

‘basket weave’

muscle

smooth, cardiac, skeletal

contract & extend

US sees mostly skeletal muscle

fibers...fascicles…muscle group…endomysium…perimysium…epimysium (muscle to bone)

what is a sign of full thickness tear

complete tendon interruption

compartment syndrome

compression of blood vessels & nerves stops blood flow to that compartment

what nerve is compressed w/ carpal tunnel

median nerve

retinaculum

band of thick, deep fascia around tendons to hold them in place

anisotropy

change in properties of structure when evaluated in different directions