NAI post pic

Non-Accidental Injury (NAI)

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Although several cases of non-accidental injury have appeared in the media recently, from Victoria ClimbiΓ© who died in 2000 at 8 years old to β€˜Baby P’ who died aged 17 months old in 2007, these are merely the tip of the iceberg. Non-accidental injury (NAI) is a recurring problem within paediatrics and it is our duty as healthcare professionals to be as vigilant as possible.

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Nearly 14 million children live in the UK. The NSPCC estimates that of these, over 58,000 are in need of protection from abuse. However, for every child identified, many more are suffering from abuse which has not been recognised.1,2

The prevalence of identified abuse is rising; the number of children in the child protection system continues to rise, with 63% of these in 2019 being due to abuse or neglect.3

It is not possible to accurately identify the prevalence of non-accidental injury because abuse is both under-recognised and under-recorded. However, nearly 6% of under 11-year-old children and 19% of 11-17-year-olds reported experiences of maltreatment or neglect in one survey.4 Nearly 10% of children reported in this same survey that they had been sexually abused in the last year.

Risk factors

History of Intimate Partner Violence and Abuse (IPV)

  • This abusive behaviour can be physical, sexual, psychological, emotional, verbal, financial, and encompasses coercive control.
  • IPV is common – at least 750,000 children per year witness IPV at home5
  • One large study found that where IPV occurs in the home within the first 6 months of a child’s life, physical abuse is 3.4 times more likely than if IPV was not present.6
  • This may be an issue highlighted in the child’s notes, or signs may be present at a consultation.
  • Questions that can be asked are shown below (based on the RCPCH child protection companion).7
  • If IPV is suspected but not documented discuss immediately with a senior colleague.

Indirect questions

  • Is everything ok at home?
  • Is your partner supportive?
  • If the woman is pregnant:
    • Are you being looked after properly?
    • Is your partner taking care of you?

Direct questions

  • Do you ever feel frightened of your partner?
  • Have you ever been in a relationship where you have been hit or hurt in some way?
  • Are you currently in a relationship where this is happening to you?

Substance Abuse or Mental Health Condition in One or Both Caregivers

  • This can increase the risk of NAI through increased burden on the caregiver/caregivers.7,8

Excessive Crying

  • Excessive crying, especially aged 0-4 months old, has been identified as a trigger for shaking of infants. This is a common cause of NAI, hence excessive crying is a risk factor for NAI within the infant population.9

Unintended Pregnancy

  • Although the majority of children whose conception was not planned are not subject to abuse, a large-scale study found that unintended pregnancy carried an odds ratio of 2.92 for maltreatment/NAI.10

Developmental Problems

  • Children with developmental concerns were twice as likely to suffer maltreatment (OR 1.99) during a large-scale study within the UK.10Β This may be due to the increased burden on caregivers, caused by these children’s complex health needs.


Safeguarding should form part of every paediatric consultation, and below are a series of injuries which the most current set of NICE guidelines identifies as suspicious for NAI.

As well as the presentation itself, the history and timeframe should be taken in to account. A patient who presents late with an obvious injury should arouse suspicion as should an implausible history for the presenting complaint.11


Shape of bruises

  • Worrying bruises are those shaped like hands, linear bruises, ligatures or an identifiable implement.

Pattern of bruises

  • Bruises on non-bony parts of the body or face/ears.
  • Multiple bruises or clustered bruises.

Age of bruises

  • Always be suspicious of bruises in a child who cannot mobilise
  • Remember β€œif they can’t cruise they don’t bruise”


Any bite which appears to be human should be treated as suspicious.

  • Bites may be caused by other children but even when bite marks are small, an adequate explanation should be sought.

Animal bites may not be classical NAI but can be a sign of a poorly supervised child.


A high index of suspicion should be present when lacerations or abrasions are seen:

  • In non-mobile children
  • Symmetrically
  • Around the face
  • Around the ankles or wrists, in the position a ligature could be applied

An adequate explanation should always be sought for the injuries described above.

Thermal Injuries

Affected area

Suspect NAI where thermal injuries are in locations you would not expect to come into contact with a hot object:

  • Soles of the feet
  • Buttocks/back
  • Backs of hands

Shape of the burn/scald

  • Suspect NAI where an injury is in the shape of a conceivable implement such as a cigarette or iron
  • Scalds with sharply delineated borders should arouse suspicion (consider immersion injury)


  • Fractures, single or multiple, in children without a medical condition predisposing them to fragile bones, should be investigated for NAI.
  • Fractures of different ages, especially where there is no documentation of caregivers seeking medical attention, are highly suspicious of NAI.
  • Metaphyseal corner fractures – reported as almost pathognomonic of NAI.
  • Evidence of occult rib fractures is also a common finding in infants/children who have been grabbed by the chest and squeezed/shaken.
  • Spiral fractures are a result of twisting forces so cannot be caused by simple falling, and are highly suspicious of NAI

Intracranial Injuries

Suspect NAI where intracranial injury presents:

  • Without an adequate explanation
  • In a child under 3 years old
  • In the presence of:
    • Retinal haemorrhage
    • Rib or long bone fractures
    • Other associated injuries
  • With multiple subdural haemorrhages

Eye Trauma

  • Retinal haemorrhages with no medical explanation are highly suspicious for NAI.


  • Spinal injuries or visceral injuries without a history of major trauma should be thoroughly investigated for suspected NAI.

Differential Diagnoses

Although it is our job to protect the children in our care, by identifying NAI where it is present, we must still consider that children are generally prone to injury. Infants, children and adolescents can often be injured perfectly innocently and so differential diagnoses must be considered when investigating for suspected NAI.8


  • This may lead to excessive bruising and haemarthrosis.
  • A family history would most likely be present, but coagulation screening should be undertaken to rule this out.

Osteogenesis Imperfecta

  • A family history may be present, and the condition would typically be detected early in life.
  • X-ray findings typically show decreased bone density, so a skeletal survey would rule this out.


The Royal College of Radiologists (RCR) has produced professional guidance on the imaging requirements when NAI is suspected, laying out which investigations should be performed and when in relation to initial presentation.12

Skeletal Survey

  • Head/chest (including AP and lateral skull)
  • Spine/pelvis
  • Upper limbs
  • Lower limbs

Follow-up Imaging

  • Skeletal survey should be repeated at 11-14 days.
  • This is to ensure that injuries too new to appear on the initial skeletal survey are detected.
  • 11-14 days is used as this is the maximal time take for the periosteal reaction to occur, allowing fractures to be visualised on X-ray.

Neurological Imaging

Imaging modality depends on the timing of the presentation, and a full algorithm can be found in the RCR guidance document.

Acute presentation

  • CT head should be performed as soon as the patient has been stabilised, on the day of presentation.

Non-acute presentation

  • MRI head should be performed as soon as possible, within a week of presentation.

Alternative Skeletal Imaging

  • CT is more sensitive in diagnosing rib fractures, but carries a higher radiation dose and so may be used if rib fractures are suspected, but CT Chest is not currently routine.
  • Ultrasound can be used to diagnose metaphyseal and rib fractures as well as identifying subperiosteal fluid.


In all cases of suspected NAI, children’s services should be involved from a very early stage and will coordinate with other agencies:

  • The child may be admitted to a paediatric ward as a place of safety whilst a social worker makes urgent enquiries and puts a safety plan in place.
  • Senior paediatric/child protection review should be undertaken.
  • A skeletal survey should be considered.
  • If abusive head trauma is suspected, the child should be referred for ophthalmology review to identify possible retinal haemorrhages.13

Other Children at Risk

You MUST identify any other related/associated children as they may also be at risk. Child Protection, Social Services and Police colleagues will play a key role in this, but it is vital to protect any other children who may be at risk. Hence it is always best to establish who else is in the home and if the child has siblings when taking any paediatric history.


  1. Rao, S. and Lux, A.L. 2012. The epidemiology of child maltreatment. Paediatrics and Child Health. Vol22(11) pp459-464. Available from: [LINK]
  2. NSPCC. How safe are our children? 2013. 2013. Available from [LINK]
  3. Department of Education. Children looked after in England (including adoption) ending 31st March 2019. Available from: [LINK]
  4. Radford LCS, Bradley C, Fisher H, Bassett C, Howat N, Collishaw S, Child abuse and neglect in the UK today. 2011.
  5. Department of Health (2005). Responding to Domestic Violence: a Handbook for Health Professionals. Available from: [LINK]
  6. Thackeray, J. D., Hibbard, R., Dowd, M. D. et al. 2010. Intimate Partner Violence: The Role of the Pediatrician. Pediatrics. 125(5) pp1094-1100; DOI: 10.1542/peds.2010-0451
  7. Royal College of Paediatrics and Child Health. 2013 Child protection companion – 2nd edition. Available from: [LINK]
  8. Gavril, A. R. Child Abuse. BMJ Best Practice. Updated February 2018. Available from: [LINK].
  9. Lee, C., Barr, R., Catherine, N. et al. 2007. Age-Related Incidence of Publicly Reported Shaken Baby Syndrome Cases: Is Crying a Trigger for Shaking? Journal of Developmental & Behavioral Pediatrics. 28(4) pp288-293. DOI: 10.1097/DBP.0b013e3180327b55
  10. Sidebotham, P., Heron, J. and ALSPAC Study Team. 2003. Child maltreatment in the β€œChildren of the Nineties:” the role of the child. Child Abuse Neglect 27. pp337-352
  11. National Institute for Clinical Excellence. 2009 (updated 2017). Child maltreatment: when to suspect maltreatment in under 18s Clinical guideline [CG89]. Available from: [LINK]
  12. Society and College of Radiographers and The Royal College of Radiologists. 2018. The radiological investigation of suspected physical abuse in children, revised first edition. London: The Royal College of Radiologists.
  13. The Royal College of Paediatrics and Child Health and The Royal College of Ophthalmologists. 2013. Abusive Head Trauma and the Eye in Infancy. Scientific Department, The Royal College of Ophthalmologists, London


Dr Sunil Bhopal

Senior Paediatric Registrar



Dr Thomas Finnerty

Paediatric Lead


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