Unfortunately, children are at significant risk for traumatic injuries, whether they be young or old. Injury prevention strategies is, obviously, the best way to avoid these events, but “accidents” do happen, so we need to be facile with managing all aspects of pediatric traumatic injuries (ex, Splenic Injury, Abdominal Trauma, Thoracic Trauma, Aortic Injury, Pelvic Trauma). Recently a colleague of ours @BurnsidePatrick inquired about Mandible Fractures in children. Well, Dr. Burnside, that is a great question (if you have a clinical question, don’t hesitate to email the question to pedemmorselsfox@gmail.com)… so let us take a moment to digest a Morsel on Mandible Fracture.

Mandible Fracture: Basics

• The mandible is the most commonly fractured facial bone (>30%) in children. [Allred, 2015; Imahara, 2008]
• Facial fractures, overall, in children are more rare than in adults.
  • The proportion of cranium to face is greater in young children compared to adults.
    • 8 : 1 (cranium : face) at birth
    • 2.5 : 1 (cranium : face) in adults
  • As children age, risk for facial injury increases. [Imahara, 2008]
• Age Matters  [Owusu, 2016]
  • Mean age for mandible fracture = 14 years 
  • For children <12 years of age
    • Fall is most common cause
    • Condyle most frequent fracture site
  • Teenagers are different (>12 years of age)
    • Assault is most common cause (~40% of cases) [Hoppe, 2015]
    • Angle of mandible is the most frequent fracture site in teenagers
• Motor Vehicle Collisions, Falls, Violence, Bicycles and Sports are the major causes. [Owusu, 2016; Smith, 2013; Imahara, 2008]

Mandible Fracture: Evaluation

• Scrutinize for other traumatic injuries. [Owusu, 2016; Allred, 2015]
  • Associated intracranial injuries found in 8.5% [Owusu, 2016]
  • Associated cervical spine fractures found in 4.4% [Owusu, 2016]
  • So, don’t need to reflexively order head and neck CT, but do need to carefully assess.
• Look for lacerations
  • External lacerations of the chin may be sign of force directed posteriorly, leading to crush injury to the condyles. [Wolfswinkel, 2013]
  • Intra-oral lacerations may change management (i.e., open fractures).
  • Any fracture through a tooth-bearing region is considered an “open” fracture and requires prophylactic antibiotic therapy. [Wolfswinkel, 2013]
• Assess for numbness
  • Fracture of the body of the mandible can lead to inferior alveolar nerve injury.
  • Check for numbness of chin or teeth.
• Assess for malocclusion
  • Asking the patient about the bite occlusion is useful.
  • Bimanual palpation (intra-orally and extra-orally) can help find asymmetry too. [Wolfswinkel, 2013]
  • Palpate the TMJ also.
• Look for loose teeth or lost teeth! (see Dental Trauma)
• TONGUE BLADE BITE TEST! [Neiner, 2016]
  • In small group of pediatric patients, this was found to be 100% sensitive and 88.9% specific.
  • Negative predictive value = 100%
  • (yes, small study… so it is worth repeating)
  • If the kid is able to break the tongue blade with her/his bite, then no mandible fracture!

Mandible Fracture: Imaging

• Panorex
  • Historically considered study of choice
  • Requires patient cooperation (tough for acutely injured children)
  • Requires specialized equipment
  • Can’t be performed on patient with possible C-Spine injury
  • Inferior to CT when looking specifically for condylar fracture. [Gelesko, 2013]
• Plain Films
  • Can provide timely information
  • Need to obtain “mandible series” = PA, Townes, Bilateral Obliques, Lateral and Subment0vertex views
• CT
  • Most versatile and useful modality
  • Particularly useful for detecting subtle or questionable fractures.
  • If Panorex shows midline mandible fracture, CT recommended to evaluate for genial tubercle fracture. [Gelesko, 2013]

Mandible Fracture: Management

• The future growth of the mandible has to be carefully considered when considering operative management.
  • The posterior borders of the condyle and ramus actively remodel for normal growth.
  • The body and symphysis undergo minimal changes normally.
• Operative vs non-operative strategies can be successfully employed.
  • “Best” strategy still debated.
  • Open reduction more likely to be needed for:
    • Multiple fractures – less stable fracture patterns
    • Certain fracture locations – ex., isolated body fracture
    • Older patients – younger patients more likely to have greenstick fractures
  • Non-surgical stabilization is also option for some injuries:
    • Condylar fractures
    • Non-displaced fractures are most often managed conservatively. [Wolfswinkel, 2013]
  • Resorbable fixation devices are also employed.
    • Strength for 4-6 weeks.
    • Degrade over course of 1-2 years.
• Soft Diet and Pain Meds!
  • Unless going to the OR, a soft diet can be initiated.
  • Patient may require period of hospitalization to ensure adequate pain control to assist with oral intake.

Moral of the Morsel

• Thoroughly evaluate the child for concomitant injuries.
• Perform Tongue Blade Bite Test! If able to break the blade, awesome! Save the kid from the CT scan.
• If clinically apparent fracture, then consider lower sensitivity tests (Panorex).
• If concern for subtle fracture, CT is the best means to truly evaluate the entire mandible.
• Do not forget the social considerations and impact of interpersonal violence! – consult your social worker and help this child avoid another ED visit due to violence.

References