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A 45-year-old man is brought to the emergency department after a high-speed motor vehicle collision in which he was a restrained driver. Although the airbags deployed, the patient's leg smashed against the front console and he had to be extricated from the vehicle. The emergency medical team placed him in a rigid cervical collar and transported him to the hospital on a backboard. He received intravenous fluids en route. Blood pressure is 138/92 mm Hg, pulse is 105/min, and respirations are 14/min. The patient is alert and oriented but has significant leg pain. Bilateral breath sounds are equal with no chest tenderness. Heart sounds are normal. The abdomen is nondistended, soft, and nontender. There is no pelvic tenderness. The right lower leg is grossly deformed, with an exposed, broken tibia. Capillary refill is <2 seconds in both feet. Plain x-rays of the right leg show comminuted fractures of the tibia and fibula.
Item 1 of 2
Which additional imaging study is most appropriate to obtain at this time?
This patient's evaluation (as with any trauma patient) began with a primary survey, which showed an intact airway, normal breathing, and hemodynamic stability. Adjunct imaging that often follows the primary survey includes portable chest and pelvic x-rays, Focused Assessment with Sonography for Trauma (FAST), and cervical spine imaging.
Cervical spine imaging should be performed whenever there is a high-energy mechanism of injury (eg, high-speed motor vehicle collision, fall ≥3 m [10 ft], trauma causing concomitant closed-head injury). Even when a high-risk mechanism is not present, imaging may still be indicated according to clinical decision rules (eg, NEXUS [National Emergency X-Radiography Utilization Study] low-risk criteria). Any 1 of the following is an indication for cervical spine imaging:
This patient has both a high-energy mechanism of injury (ie, high-speed motor vehicle collision) and a painful, distracting injury (open right tibia-fibula fracture). Therefore, he should undergo cervical spine imaging (Choice E). CT scan of the cervical spine is the preferred screening test to evaluate for cervical spine injury because it is significantly more sensitive than plain radiography (eg, ~98% vs ~52% sensitivity). Imaging should be done prior to performing urgent surgical intervention (eg, irrigation, fixation) for the patient's open fracture because he may require orotracheal intubation and neck manipulation.
(Choice A) CT angiography of the lower extremities may be indicated if clinical signs of vascular injury (eg, diminished pulses) are present following trauma. Although tibia-fibula fractures may be associated with vascular injury in some patients, this patient has normal capillary refill (ie, <2 sec) in both feet. Complete pulse examination and measurement of the injured extremity index (analogous to the ankle-brachial index) would be better next steps than CT angiography.
(Choices B and D) Portable chest and pelvic x-rays and FAST are commonly performed as adjuncts to the primary survey. If evidence of injury is found in these screening studies, CT scans of the chest/abdomen/pelvis are typically performed afterward. Occasionally, CT may be the initial test when such significant injuries are found on physical examination that CT is already deemed necessary. However, examination of this patient's chest, abdomen, and pelvis are normal.
Educational objective:
CT scan is the preferred test to screen for cervical spine injury. Indications include high-energy mechanism of injury or any of the following findings: neurologic deficit, spinal tenderness, altered mental status, intoxication, or distracting injury.