Intra-oral injury and occult trauma — formative SAQs

SAQ 1 (10 marks)

A 4-month-old infant presents with a 2-day history of poor feeding and irritability. The mother says the baby " bumped the mouth on the cot rail" two days ago. On examination, the upper labial frenum is torn and bruised, and there is a small bruise behind the left ear. The baby does not roll, sit, or crawl. There are no other external injuries, and the child is haemodynamically stable with a normal neurological examination. ^{[3] [5]}

1. State three features of this presentation that indicate this is a sentinel injury requiring a safeguarding workup, and name the bruising clinical decision rule that applies. (3) ^{[7] [8]}
2. Outline the occult-trauma screen you would perform, with the specific threshold that triggers abdominal imaging. (4) ^{[9] [14]}
3. Describe the immediate safeguarding actions you must take before considering discharge. (3) ^{[3] [5]}

Model answer — SAQ 1

(1) Sentinel-injury features and the bruising rule (3). Three features: the child is non-mobile (does not roll, sit, or crawl) — any bruise or oral injury in a pre-mobile infant is highly suggestive of abuse (Maguire 2005); the torn upper labial frenum is a classic inflicted oral sign (Kellogg 2005) and an "F" item in the TEN-4 FACES-B rule; the bruise behind the left ear is an "E" (ear) item. The rule is TEN-4 FACES-B (Pierce 2010, validated 2021): bruise on Torso, Ear, or Neck; any bruise under 4 months; Frenulum tear; Angle of jaw, Cheek, Eyelid, Sclera; Bruising in any non-mobile child. ^{[1] [7] [8]}

(2) Occult-trauma screen (4). Skeletal survey — a complete series of approximately 20 views including oblique ribs, for all children under 24 months with suspected abuse (AAP Section on Radiology 2009), with a repeat at 2 weeks to reveal fractures not initially visible. CT head acutely (this infant is under 6 months with an abusive injury and irritability), followed by MRI brain and spine when stable for injury dating and diffuse axonal injury. Dilated specialist ophthalmology for multilayer retinal haemorrhages. AST and ALT — if either is over 80 IU/L, perform abdominal CT for occult liver injury (Lindberg 2013); add lipase and urinalysis. Coagulation and FBC to exclude bleeding diathesis. ^{[2] [9] [14]}

(3) Immediate safeguarding actions (3). Do not discharge the child without a safeguarding plan and a senior-clinician decision — the child must not be returned to an unsafe environment while the workup is pending. Make a mandatory report to child protection — the threshold is reasonable suspicion, not certainty. Notify a senior clinician and the local child-protection team, and engage social work. Do not confront or accuse the carer; document the history verbatim with quotations, photo-document injuries on a body map, and follow institutional forensic protocol. ^{[3] [5]}