Paediatric Trauma Anatomy – Easy as AcBC

Authors: Charlotte Davies & Nikki Abela / Reviewer: Fatimo Omotayo Jibowu / Codes: T1 / Published: 27/11/2017 / Reviewed: 21/07/2026

The alert phone goes: the ambulance team are bringing in a 2-year-old girl who has fallen down a flight of stairs. Her GCS is low, her c-spine is immobilized and she’s tachycardic.

You panic: It has been a while since you managed a trauma patient so young.

“Children are not young adults,” echoes in the back of your mind.

“Why not?”, you think.

The answer is all in their anatomy.

This blog runs through some of the anatomical differences in children, and how they affect the injuries they might present with – and what better order to do this in than xABCDE?

Reviewer note (NA): When I talk about childrens differences I feel like I am talking about a spectrum, almost like a colour scale from black to white with grey in between. If the adults are black and the children are white, then a neonate is a brilliant white and a tween is dark grey. If you take this imagery and apply it to the child in front of you, then you can decide how different to an adult your specific paediatric case is (very different, or not at all different).

X (eXsanguinating haemorrhage) – prioritising life-threatening bleeding first. – Although less common in children than adult, this should be identified and controlled early as it remains an immediate life-threatening cause of preventable death. Children have a smaller blood volume and can deteriorate rapidly with modest blood loss.

Recognizing uncontrolled bleeding, using direct pressure, haemostatic dressings and early use of blood products are key principles.

Worthy to note that in Paediatric trauma the main cause of preventable death is not haemorrhage but failure to oxygenate and ventilate but catastrophic haemorrhage must still be actively sought and managed.

As we are now taught a horizontal approach, exsanguinating haemorrhage and ABC should be managed concurrently.

Airway

Children tend to have a larger tongue, smaller jaw and shorter, narrower, airway with an anterior larynx. The larynx was classically described as funnel shaped, but modern imaging in recent research has challenged this.

This means that the tongue is more likely to block the airway than in adults. Moreover, the occiput is more prominent meaning that at rest their neck is flexed and their airway closed.

The narrow airway also means that a very slight amount of oedema leads to significant airway compromise and resistance 1mm of oedema can reduce a patients airway by 60% (you all remember Poiseuilles law no?).

Foreign bodies are more likely to go through the cords and get stuck at the cricoid due to the Cricothyroid ring being the narrowest part, whereas in adults, foreign bodies are more likely to get stuck in the cords. Depending on the age of your patient, they may be loosing their primary incisors which may be your foreign body, or they may be loose or missing affecting your airway management further.

Nasopharyngeal airway is not recommended in paeds especially in younger children and should generally be avoided in suspected base of skull or significant midface trauma, Oropharyngeal airway use in a conscious child would induce vomiting due to an intact gag reflex

The airway is short and easily blocked you might need to put a cushion underneath the shoulders to maintain neutral alignment.

Because the airway is short, if you are intubating, a main bronchus intubation is likely so its really important to do your calculations right (Estimate ETT depth 3X internal diameter of tube) and watch the black line on the ETT pass through the cords.

C-Spine

Children have very flexible and elastic spinal ligaments, so there is a lot of c-spine movement. Their vertebrae are anteriorly wedged with flat facet joints. This combined with their large head, means that children have a relatively high fulcrum, and the spine moves a lot, with lots of forces being applied to C1and 2.

Although abnormalities between C1 and 2 are more likely, pseudosubluxation is also seen here between C2/3 (24% < 8yrs) and C3/4 (14%). It can be difficult to tell the difference between true subluxation and injury, and a pseudosubluxation. Swischuks Line can be useful – this is a line drawn between the posterior arch of C1 and C2. It is a dislocation if line misses the anterior cortex of C2 by > 2 mm. I think, Id be speaking to my friendly radiologist about this – or reading the RCEMLearning blog: Spinal Injuries in Children.

Collars are unlikely to help immobilise the c-spine in children, and their use in children is not routinely taught on APLS who suggest manual inline immobilsation, followed by blocks and tape when necessary.

Due to the increased risks associated with irradiation, particularly to the thyroid gland, and the generally lower risk of significant spinal injury, CT of the cervical spine probably should NOT ROUTINELY be used and there is more covered on this here.

The Royal College of Radiology guidelines also do not suggest the routine use of CT c-spine in the paediatric population, with exceptions:

You are doing a CT head and are worried about the C-spine
A GCS less than 13 or patient is intubated
Focal neurological signs.
Definitive diagnosis of cervical spine injury is needed urgently (for example, before surgery).
Another body area scanned
There is strong clinical suspicion of injury despite normal X-rays. (reviewer note: In this case if I know a normal x-ray is not going to reassure me, I ask the radiologist to go straight to CT)
Plain X-rays are technically difficult or inadequate.

The RCR instead suggest early neurosurgical involvement. They also suggest that C1-3 is included on a head CT, as this is a high risk spot for injury. Interpreting images can be difficult phone a friend!

Breathing

Children have a very soft, pliable chest wall meaning that pulmonary contusions without rib fractures are possible. Because children’s bones are more compliant, forces applied across the chest wall will cause movement and then recoil.

Children also have horizontally aligned ribs and weak intercostal muscles, so rely more on diaphragmatic breathing than adults. A tension pneumothorax is more likely due to their very mobile mediastinum. (it is the commonest immediate life-threating injury, Needle decompression should be done at mid clavicular line second interspace if identified)

Hypoventilation causes respiratory acidosis which is the most common acid base abnormality seen before hypoxic cardiac arrest, with adequate ventilation, a child should be able to maintain relatively normal PH.

When ventilating a child, Use paediatric BVM if <30kg so as to prevent barotrauma due to over inflation.

Children also inhale a lot of air, especially when screaming. This can cause gastric dilatation, which in turn can cause an ileus.

When interpreting the CXR, if this is normal, the patient is conscious and clinically stable, a CT is unlikely to be indicated in blunt trauma. This means we have to carefully evaluate the chest we might not see evidence of pulmonary contusions, and we must think twice about whether there is a tension pneumothorax.

Due to the risk of vascular injury, CT is indicated as the primary modality in penetrating trauma.

Circulation

With a smaller circulating volume, children obviously have a lot less blood to lose- so seemingly small losses to an adult may mean a big deal to a child. Their stroke volume is pretty fixed and therefore the only way of increasing their cardiac output is to increase their heart rate so pay attention to a tachycardia, especially in a calm child.

Whats worse than small circulating volumes, is that they are also more likely to lose it from their lower-riding liver and spleen, that is not protected well from their softer, thinner, abdominal wall (less musculature, less fat, more square abdomen).

Its not just their upper abdominal organs which are more exposed, the bladder is also an intra-abdominal organ in young children (and lies at the level of the umbilicus at birth) so is especially vulnerable.

The intestine also, especially the sigmoid and right colon, are not fully attached in the peritoneal cavity in young children and are more likely to be injured with forces of compression or sudden deceleration.

The Holmes prediction rule can help us to know if children need abdominal imaging or not:

This means we have to examine the abdomen carefully for bruising, and remember that the bladder, spleen and liver have minimal protection against trauma. Blunt renal trauma is also more likely as children have less protective perinephric fact, and the kidneys are relatively large compared to the rest of the abdomen. Significant haematuria should be taken seriously and investigated further.

Not only, but once found, an abdominal injury should alert the physician to re-examine the spine. Dont forget that Chance fractures, a.ka. seatbelt fractures, are commonly associated with abdominal injuries. They are flexion-distraction type injuries of the spine, that typically come about from a poorly restrained (seat-belt only) RTC. They involve all three spinal columns and are unstable injuries.

Thankfully, pelvic fractures are rare, but if suspected they are harder to splint SAM splints are hard to cut to size, prometheus on the other hand are fairly easy. You might find that some crafting with a sheet is necessary, if your department doesnt stock anything suitable.

Disability

Because the head is so much bigger, the chance of injury is increased in the paediatric population.

In younger children, the cranium is softer, with open fontanelles (until 12 – 18 months), so it is possible to get significant injury, with minimal external signs. Because their craniums arent closed, this means there is extra space for haemorrhage to expand into, meaning a significant injury can hide there without causing a decreased GCS or signs of increased ICH. Don’t forget to palpate the fontanelle, look inside and behind the ears (the younger the child, the less there is to go on so make the most of your examination), and observe the child if needed. The NICE guidelines for head injury are commonly used, and are a good guide for imaging. If sending the parents home, do safety-net appropriately if this is late in the day, I do sometimes advise the parents (with little evidence) to rouse the child overnight to make sure they are ok.

Children also have a higher body surface area to mass ratio with thinner skin and less insulation by subcutaneous tissue so might get cold a lot more quickly than adults- cover them up and warm them appropriately.

Exposure

Exposure in children is a lot more important, as many of them are non-verbal. Remember, non-verbal children wont tell you about the pain in their fractured tibia. Even verbal children tend to get easily distracted, and dont notice quite large injuries so exposing them is key to finding more injuries.

Exposure is also key to picking up multiple injuries in cases of non accidental injuries, and therefore a careful A-E assessment must be done. Remember, non-verbal children can’t tell you what’s happened to them, and it’s your responsibility to double check the history you’ve been given.

When facing paediatric trauma, remembering that children are not young adults, can be paralysing. There are differences which lie on a spectrum, but dont let them scare you. Mentally rehearse your actions, and you will be fine.

Take Home Message Children are not simply small adults; their unique anatomy influences both the pattern of injuries they sustain and how those injuries should be assessed and managed. Understanding these differences is essential when approaching paediatric trauma, from airway management and cervical spine assessment to recognising occult chest, abdominal and head injuries. A structured AE assessment remains the cornerstone of trauma care, but clinicians must adapt their examination, imaging decisions and management strategies to the paediatric patient. When in doubt, seek senior or specialist advice, and remember that a thorough examination and careful clinical judgement are often more valuable than rushing to advanced imaging.