Head and spinal injuries: systematic review

Child Protection Evidence is a resource for clinicians across the UK and internationally to inform clinical practice, child protection procedures and professional and expert opinion in the legal system.

Summary

This systematic review evaluates the scientific literature on abusive and non-abusive head and spinal injury published up until June 2018 and reflects the findings of eligible studies. The review aims to answer five clinical questions:

1. 1. What neuroradiological investigations are indicated to identify abusive head trauma (AHT) in children?
   2. What are the distinguishing clinical features of abusive head trauma in children?
   3. What neuroradiological features distinguish abusive from non-abusive head trauma (nAHT)?
   4. Can you date inflicted intracranial injuries in children neuroradiologically?
   5. What are the clinical and radiological characteristics of spinal injury in abusive head trauma?

Fifteen new high-quality studies published between 2014 and June 2018 met the inclusion criteria and have been included in this systematic review with new evidence added to each clinical question. Three studies included useful information regarding the identification of occult abusive head trauma (AHT) and a study that explored whether children with ‘acute/chronic subdural haemorrhage (SDH)’ represent repeated trauma or rebleeding are summarised in the useful reference section.

Six new studies addressed clinical question one, regarding the neuroradiological investigations that are indicated to identify AHT. The advent of more studies using MRI has expanded the ability to identify and interpret parenchymal lesions. Three studies provided data that compared computerised tomography (CT) and Magnetic resonance imaging (MRI) findings. Two studies explored the findings of advanced MRI techniques that can characterise the nature and extent of parenchymal lesions in comparison to standard MRI in children with AHT and one study assessed the utility of high-resolution coronal susceptibility-weighted imaging (SWI) in depicting bridging vein thrombosis and the rupture of bridging veins.

The second question, ‘what are the distinguishing clinical features of abusive head trauma in children’ only included data from three new studies. Eight studies were added that described the neuroradiological features that distinguish abusive from non-abusive head trauma, and enabled an update of the meta-analyses.

Limited new evidence was available when assessing the dating of intracranial injuries from AHT neuroradiologically, one systematic review was added which assessed the dating of subdural hematomas found on CT and MRI scans.

The clinical and radiological characteristics of spinal injuries in AHT were investigated in four new studies.

Key findings:

Question 1 ‘What neuroradiological investigations are indicated to identify abusive head trauma in children?

Widely accepted clinical guidelines used as part of best practice promote a computerised tomography scan (CT) as the preferred first line imaging technique in acutely ill children with suspected AHT in all children less than one year of age when physical abuse is suspected.

• • Evidence shows that if the initial CT is abnormal, magnetic resonance imaging (MRI) has the capacity to identify further intracranial lesions, particularly parenchymal lesions.
  • Studies describe a number of children with AHT who have a normal initial CT scan, but abnormalities were identified on MRI.
  • Advanced MRI techniques have the ability to further delineate the extent and regions of parenchymal damage in terms of abnormal; parenchymal diffusion, cerebral blood flow, haemorrhage. These features can help to inform the full extent of brain injury and the prognosis.
  • Cranial ultrasound is not an effective diagnostic investigation, whilst it can identify some features, it will miss many others. High resolution ultrasound scans (USS) may have some advantage as a secondary investigation in experienced hands to monitor or follow the development of a lesion already identified on CT or MRI.

Question 2: What are the distinguishing clinical features of abusive head trauma in children?

• • Certain features (retinal haemorrhage, apnoea) correlate strongly with AHT rather than non-abusive head trauma (nAHT) in children less than three years of age.
  • Other features such as seizures, rib and long-bone fractures show a positive association with AHT that failed to reach statistical significance (once missing data had been accounted for).
  • Skull fractures and bruising to the head and neck were more strongly associated with nAHT but this association failed to reach statistical significance.

Question 3: What neuroradiological features distinguish abusive from non-abusive head trauma?

• • Subdural haemorrhages (SDH) are statistically significantly associated with AHT, subarachnoid haemorrhages are equally prevalent in AHT and nAHT and extradural haemorrhages are statistically significantly associated with nAHT.
  • Subdural haemorrhages in AHT are significantly more likely to be multiple, occur in the interhemispheric fissure, over the convexities, in the posterior fossa and be bilateral than SDHs in nAHT.
  • Multiple SDH identified on CT scans of different attenuations and those of low attenuation are more commonly seen in AHT than nAHT. Those of mixed attenuation (different attenuation seen in the same SDH) have been reported in both AHT and nAHT.
  • Cerebral oedema, hypoxic ischaemia, diffuse axonal injury and closed head injury were statistically significantly associated with AHT as compared with nAHT.

Question 4: Can you date inflicted intracranial injuries in children neuroradiologically?

• • The time scale of the different appearances of subdural haemorrhages as they resolve, vary and overlap mean that CT or MRI findings cannot be used to accurately date SDH.

Question 5: What are the clinical and radiological characteristics of spinal injury in abuse head trauma?

• • There is a significant association between spinal injury found on MRI and AHT, particularly in the cervical region. The prevalence of spinal injury in AHT ranges from 13%-78%.
  • There is growing evidence of an association between ligamentous injury and soft tissue injury to the cervical spine and AHT.
  • Spinal subdural haemorrhages reported in AHT were associated with intracranial SDH. (there is debate as to whether this relates to redistribution of intracranial SDH).
  • These findings would support consideration of a guideline to include spinal MRI in the assessment of children with AHT to include Short TI Inversion Recovery (STIR) sequences.