Key Facts

Non-accidental injury encompasses all forms of physical abuse inflicted on children. Healthcare professionals must be vigilant for patterns of injury that are inconsistent with the history provided. Early recognition and appropriate safeguarding action are essential to prevent further harm and potentially save lives.

Epidemiology

Physical abuse accounts for approximately 10% of child protection registrations in the UK. Infants under 1 year are at highest risk — the incidence of abusive head trauma peaks in the first 6 months of life. Approximately 1 in 10 children experience physical abuse during childhood. Boys and girls are equally affected. Children with disabilities are 3-4 times more likely to experience abuse.

Aetiology

Risk factors:

• Young infant (highest risk <1 year)
• Prematurity, low birth weight, chronic illness
• Parental: Mental health problems, substance misuse, domestic violence, social isolation, young parents
• Household: Unrelated male in household (significant risk factor for abusive head trauma), poverty, overcrowding
• History of abuse in parents' own childhood

Pathophysiology

Abusive head trauma (AHT): Violent shaking ± impact causes:

• Acceleration-deceleration injury → tearing of bridging veins → subdural haematoma (typically bilateral, thin-film)
• Axonal shearing → diffuse axonal injury
• Retinal haemorrhages (particularly multilayered, extending to periphery) — found in ~85% of AHT

Fractures: Direct impact or twisting forces cause fractures; the pattern reveals mechanism — posterior rib fractures from squeezing, metaphyseal lesions from twisting/traction forces.

Burns: Immersion burns show clear tide marks and sparing of flexural creases. Contact burns reproduce the shape of the object (cigarette, iron, etc.).

Bruising Patterns

• Suspicious locations: Ears, neck, trunk, buttocks, upper arms (away from bony prominences)
• Normal accidental locations: Shins, knees, forehead (bony prominences)
• Shape: Patterned bruising (hand slap marks, belt marks, bite marks)
• Age: Non-mobile infants with ANY bruising — highly suspicious
• 'TEN-4' rule: Bruising to Torso, Ears, Neck in child <4 years or ANY bruising in infant <4 months

Fracture Patterns

• Multiple fractures at different stages of healing
• Rib fractures in infants (especially posterior)
• Classic metaphyseal lesions (corner/bucket handle fractures)
• Femoral fractures in non-ambulant children
• Skull fractures: Complex, bilateral, or non-parietal

Abusive Head Trauma

• Subdural haematoma (bilateral, thin-film, mixed density)
• Retinal haemorrhages (multilayered, extending to periphery)
• Encephalopathy (seizures, altered consciousness, apnoea)
• Scalp swelling, fontanelle bulging

Burns

• Immersion scalds: Clear tide marks, bilateral symmetrical, sparing of flexor creases
• Cigarette burns: Circular, deep, often multiple
• Contact burns: Shape of object (iron, radiator)

Red Flags

• ANY injury in a non-mobile infant
• History inconsistent with injury or child's developmental stage
• Delay in seeking medical attention
• Changing or inconsistent account from caregivers
• Multiple injuries of different ages
• Child's demeanour: Frozen watchfulness, withdrawal

Bedside

• Full head-to-toe examination: Undress completely; examine all skin surfaces including scalp, ears, mouth (torn frenulum), genitalia
• Body map: Document every injury — size, shape, colour, location, tenderness
• Clinical photography: With appropriate consent or best interest decision
• Detailed history: Separate accounts from each caregiver; note inconsistencies
• Developmental assessment: Can the child perform the action described?

Bloods

• FBC: Platelets, anaemia
• Coagulation screen: PT, APTT, fibrinogen — exclude clotting disorder
• von Willebrand screen: vWF antigen, ristocetin cofactor activity
• Bone profile: Calcium, phosphate, ALP — exclude metabolic bone disease
• Vitamin D (25-OH): Deficiency predisposes to fractures
• LFTs and amylase/lipase: Screen for occult abdominal trauma
• Urinalysis: Haematuria may indicate renal trauma

Imaging

• Skeletal survey (mandatory <2 years): Full series as per RCPCH/RCR guidelines — AP and lateral skull, AP chest with oblique ribs, AP spine, AP pelvis, AP long bones, AP hands and feet
• Repeat skeletal survey at 11-14 days: Detects healing fractures not visible on initial films
• CT head (urgent): If suspected abusive head trauma — subdural haematoma, cerebral oedema
• MRI brain (within 5 days): More sensitive for diffuse axonal injury, parenchymal damage, dating of haemorrhage
• Abdominal CT with contrast: If occult abdominal injury suspected (raised LFTs/amylase)

Special Tests

• Ophthalmology review: Dilated fundoscopy by paediatric ophthalmologist — retinal haemorrhages in AHT
• Genetic testing: If osteogenesis imperfecta or other genetic condition suspected
• Bone biopsy: Very rarely needed; only if OI strongly suspected with normal genetics

Non-pharmacological

• Ensure child's immediate safety: Admit to hospital if any concern about safe discharge
• Multi-agency referral: Contact children's social care (telephone + written within 24h)
• Police notification: If criminal offence suspected
• Strategy discussion/meeting: Social care, police, health — within 24 hours
• Child protection medical: Full examination by consultant paediatrician experienced in child protection
• Section 47 enquiry: Social care-led investigation into significant harm
• Document everything: Contemporaneous, factual, detailed, objective notes; use body maps; record verbatim quotes
• Named/designated safeguarding professional: Inform and involve

Pharmacological

• Appropriate analgesia for injuries: Paracetamol 15mg/kg QDS, ibuprofen 5mg/kg TDS
• Treat specific injuries as clinically indicated
• Anticonvulsants if seizures secondary to head injury

Surgical/Interventional

• Neurosurgical input: Subdural haematoma may require drainage
• Orthopaedic management: Fracture stabilisation as needed
• General surgical input: If abdominal injuries identified

Referral Criteria

• ANY suspicion of NAI — immediate safeguarding referral
• All cases: senior paediatric review, social care, police
• Abusive head trauma — neurosurgery, ophthalmology, PICU
• Uncertain diagnosis — seek advice from named/designated doctor for safeguarding
• Never discharge a child if there is an unresolved safeguarding concern

• Abusive head trauma mortality: 20-25%; approximately 50% of survivors have significant long-term neurological disability (cerebral palsy, epilepsy, visual impairment, cognitive impairment)
• Re-abuse: Without effective intervention, approximately 30-50% of physically abused children experience further episodes
• Fatal child abuse: Approximately 50-70 children per year die from abuse/neglect in England
• Long-term outcomes: Increased risk of mental health problems, substance misuse, criminality, intergenerational transmission of abuse
• Protective factors: Early intervention, stable foster/adoptive placement, therapeutic support significantly improve outcomes
• Siblings: Must ALWAYS be assessed — they are at high risk of concurrent abuse

High-Specificity Injuries for Abuse

NAI Investigation Checklist