Nonaccidental Injuries (NAI)

• Aka: Child abuse, Non accidental injury, shaken baby syndrome, nonacccidental head injury, abusive head trauma

• Inflicted cranial and spinal injuries resulting from blunt force trauma, shaking or a combination of forces

• Leading cause of death in child abuse

• This is the most serious form of physical abuse out of all the child abuses
• Mortality: 30%
• Morbidity: 50% (of survivors)

• At least 10% of children <10 yrs of age that are brought to E/R with alleged accidents are victims of child abuse.

• The incidence of accidental head trauma of significant consequence below age 3 is low, as this is the age group in which battering is highest.

• Majority of patients <1 yrs old

• Baby factor
• Prematurity
• Twin male
• Physical handicaps
• Stepchild

• Parents factor
• Young parents
• Dec. Socioeconomic status
• 1/3 of parents are under influence of drug or alcohol when abusing the baby

• Direct impact injury
• Direct blow to head or head impact onto an object
• Skull fractures and injury to underlying brain

• Shaking injury: Violent "to and fro" of head
• Diffusely distributed subdural haematoma
• Cortical contusion
• Axonal injury
• Parenchymal lacerations

• Hypoxic ischaemic injury
• Initial cardiorespiratory arrest
• Seizures through excitotoxic process
• Glutamate
• Secondary energy failure

• Scalp injuries

• Skull fractures

• Intracranial haemorrhage
SDH
• Significantly associated with AHT (>50% cases)
• Location
• Convexity
• Interhemispheric
• Post fossa
• Secondary to tearing of bridging veins
 

 
• Timing
Density evolution of haemorrhage on CT

Stage	Appearance	Estimate of age
Hyperacute	Isodense	< 3 hours
Acute	Hyperdense	Few hours → 7-10 days
Subacute	Isodense	2-3 weeks
Chronic	Hypodense	> 3 weeks

• Acute (hrs -days)
• 60% homogenously hyper dense
• 40% mixed hyper, hypodense
• Torn arachnoid with CSF accumulation
• Active bleeding (swirl sign)
• Clot retraction
• Rare: isodense aSDH
• Anaemia
• Coagulopathy
• Subacute (7-22 days)
• Rapid, variable changes
• Density
• Iso: 40%
• Hypo: 50%
• Hyper: 10%
• Neomembranes develop by 2-3 wks
• Mix density SDH:
• IS NOT acute on chronic haemorrhage
• Rather it is (can derive from a single traumatic event)
• Hyper acute + acute blood
• Acute haemorrhage alone
• Haematohygroma (acute HGE + CSF from arachnoid tear)
• Combination of new and old haemorrhage
• Chronic (>22 days)
• Features related to age and rebleed from neomembranes
• Isodense (87%)
• Hypo (13%)
• Subdural hygromas



• CSF like density/intensity
• Part of evolution of SDH

flowchart LR
    A["HEAD TRAUMA"] == BV injury ==> B["acute SDH"]
    B == "rapid resorption of subdural blood<br>cleaved dura-arachnoid-interface under decreased ICP<br>CSF and CSF-like liquid effuses from the environment" ==> C["Subdural hygroma"]
    B -. "approx. 1/3" .-> E["complete resolution / resorption"]
    C -. majority .-> E
    C == expansion under decreased ICP<br>formation of neomembranes including new vessels (neovascularization)<br>microhemorrhages ==> D["chronic SDH"]
    B --> D
    A -.-> C

    style A stroke:#D50000, fill:#D50000, color:#FFFFFF
    style B stroke:#D50000, fill:#D50000, color:#FFFFFF
    style C stroke:#D50000, fill:#D50000, color:#FFFFFF
    style E stroke:#00C853, fill:#00C853, color:#FFFFFF
    style D stroke:#D50000, fill:#D50000, color:#FFFFFF
    linkStyle 0 stroke:#D50000,fill:none
    linkStyle 1 stroke:#D50000,fill:none
    linkStyle 4 stroke:#D50000

• May develop acutely
• Neomembranes
• Begin to form within SDH by 2-3 wks and mature by 4-5 wks
• MRI >>>> CT: Membranes enhances
• Contains fragile capillaries --> risk of rebleeds
EDH
SAH
IVH
IPH

• Cerebral contusions

• Shear injuries

• Ischaemic brain injuries

• Highly variable
• Irritability
• Vomiting
• Apnea
• Seizure
• Obtundation

• Vague and variable hx

• "Killer couch" -FAKE
• Injuries attributed to infant rolling off couch onto floor
• Chadwick 2008: Annual risk of death resulting from short falls among young children: less than 1 in 1 million

• There are no findings that are pathognomonic for child abuse. Factors which raise the index of suspicion include:
• Retinal haemorrhage
• Bilateral chronic subdural hematomas in a child< 2 yrs of age
• Skull fractures that are multiple or those that associated with intracranial injury
• Significant neurological injury with minimal signs of external trauma
• Multiple injuries of different ages in multiple locations
• Bruising on the buccal surface of the lips is a high risk sign of NAI

• Skull fx on x-ray or clinical signs of intracranial injury → CT →
• MRI
• to assess extent of injury and to confirm injury
• Also to be done in patients with abuse even with no evidence of intracranial injury

• X-ray skeletal survey

• Bone scintigraphy

• U/S

• CT
• Test of choice
• Pros
• Quick
• Avoid sedation
• Easily accessible
• Accurately detects subdural haemorrhage and fx
• Cons
• Exposure of brain to ionizing radiation
• Babies more vulnerable, has longer life span to develop cancer
• Protocol
• Age adjusted settings → reduce radiation
• Soft tissue reconstruction at 3mm, bone reconstructions at 0.6mm
• MPR
• Improves intracranial haemorrhage and fracture detection
• 3D

• MRI
• Performed 48-72 hrs after presentation
• Pros
• Avoid radiation
• Cons
• Requires child to motionless for mins to hrs
• May require sedation
• Most centres don't have the resource to do this
• Protocol
• DWI
• Sag T1 3d + MPR
• T2 axial +Coronal
• Sag Flair 3D + MPR
• SWI
• MR venogram with contrast
• Contrast enhanced T1 3D + MPR
• Fast MRI
• Featurs
• Abbreviated exam
• Motion tolerant sequences
• Avoid sedation
• Eliminates radiation
• Use fq in shunted hydrocephalus
• Composed of
• Axial and Coronal T 2 SSH
• Axial Tl SSH TFE
• Axial FLAIR SSH
• Axial gradient echo
• Axial DWI
• Total scan time 6 min
• Of the 223 pts, CT identified TBI in 50% skull fractures, subdural hematomas, SAH
• Fast MRI:
• Sensitivity 93%, Specificity 96%
• 8 cases of TBI visible on CT, missed by Fast MRI
• 5 cases of TBI visible on Fast MRI, missed by CT
• 4 cases where CT raised concern for hypodense SDH but fast MRI concluded enlarged subarachnoid spaces

• Acquired microcephaly (93%)

• Early post-traumatic seizures (79%)

• Late post-traumatic epilepsy (>20%)

• Poor visual outcome (20-65%)

• Outcome

Condition	Percentage Range
Death	20-25%
Spastic hemiplegia or quadriplegia	15-64%
Intractable epilepsy	11-32%
Microcephaly with cortico-subcortical atrophy	61-100%
Visual impairment	18-48%
Language disorders	37-64%
Agitation, aggression, tantrums, attention deficits, memory deficits, inhibition or initiation deficits	23-59%

• Coagulopathy

• Leukaemia

• Haemangiomas

• Osteogenesis Imperfecta

• Glutaric Aciduria Type 1 — SDH and macrocephaly

• Brain injury due to vigorous shaking of child

• Vigorous shaking --> whiplash-like angular acceleration-decelerations of the head (the infant head is relatively large in proportion to the body, and the neck muscles are comparatively weak) --> brain injury.
• Some researchers believe that shaking alone may be inadequate to produce the severe injuries seen, and that impact is often also involved.

• Clinical features
• Retinal haemorrhages
• Extradural haematoma
• External trauma required
• Subdural hematomas (bilateral in 80%)
• No external trauma required
• Subarachnoid haemorrhage (SAH).
• Few or no external signs of trauma
• including cases with impact, although findings may be apparent at autopsy.
• Finger marks on the chest,
• Multiple rib fractures and/or pulmonary compression ± parenchymal lung haemorrhage.
• Deaths in these cases are almost all due to uncontrollable intracranial hypertension.
• There may also be injury to the cervicomedullary junction.

• the presence of RH is pathognomonic of NAI.

• RH may also occur in the absence of any evidence of child abuse.
• 16/26 battered children < 3 yrs of age had RH on fundoscopy, whereas,
• 1/32 non-battered traumatized children with head injury had RH
• The single false positive: traumatic parturition, where the incidence of RH is 15–30%.

• Differential diagnosis of aetiologies of retinal haemorrhage:
• Child abuse
• benign subdural effusion in infants
• acute high altitude sickness
• acute increase in ICP:
• e.g. with a severe seizure
• Purtscher’s retinopathy:
• loss of vision following major trauma (chest crush injuries, airbag deployment…), pancreatitis, childbirth or renal failure, among others.
• Posterior pole ischemia with cotton-wool exudates and haemorrhages around the optic disc due to microemboli of possibly fat, air, fibrin clots, complement-mediated aggregates, or platelet clumps.
• No known treatment

• Parietal bone was the most common site of fracture in both groups (≈ 90%)

• Depression of skull fractures was frequently missed clinically due to overlying hematoma

• Clinical features in patients with skull fractures (retinal haemorrhage) did not reliably differentiate child abuse from trauma

• 3 characteristics more frequently seen after child abuse than after other trauma:
• Multiple fractures
• Bilateral fractures
• Fractures that cross sutures

• Venous thrombosis causing SDH from back pressure
• No evidence for this mechanism in autopsy or case reports
• Basically back pressure is not high enough to cause SDH

• Hypoxic ischaemic injury causing SDH in paeds
• False

• Sustained Valsalva from coughing or choking causes SDH or retinal haemorrhage
• Raised Intrathoracic pressure --> inc. venous pressure --> venous rupture of
• Fake

• SDH due to rebleeding secondary to birth related SDH
• Birth related trauma
• Scalp soft tissue
• Skull
• Extracerebral/intracranial haemorrhage
• Brain parenchymal injury (haemorrhage/contusion)
• Birth related SDH is present in 50%
• Due to vaginal delivery, spontaneous and assisted
• Associated with longer first and second stages of labour
• Increase prolonged propulsive and compressive forces, increased moulding and overlapping of sutures
• Vast majority resolve by 4 wks if not by 3 months all resolved
• No evidence for this mechanism as an explanation for SDH

• Enlarged subarachnoid spaces
• Idiopathic enlargement at 1 yr of life
• Subdurals occur in 5.3% of cases of enlarged subarachnoid spaces
• Mech (unknown)
• Immature CSF drainage
• Typically bifrontal +/- ventriculomegaly
• No neurological sequelae after resolution (2 yrs to resolve)
• However if there is an increase in OFC above 95% think of abuse
• If concerned get an MRI

flowchart LR
    C["Timely presentation and consistent history"] --> D["No injury identified"] & F["Injury identified: manage<br>injury<br>discuss with senior"]
    D --> E["Discharge patient"]
    F --> G["Discharge"] & H["Any concern identified"]
    H --> I["Admit under shared care<br>appropriate specialty/child<br>protection team<br>Consider the need for: CTH,<br>Skeletal survey, NAI bloods<br>(See below), Ophthalmology<br>review,<br>Contact Stand-by Social<br>Work and/or Police to<br>ensure safety of siblings"]
    A["Presentation to ED<br>with physical injury<br>(Child &lt; 1 year of age)"] --> n1["Concern about hx<br>Discuss with senior"] & C
    n1 --> n2["Senior has no concern"]
    n2 --> n3["Discharge"]
    n1 --> H

• Senior: Child protection team and consultant