CAISS Spine Injuries 3 — Questions and Answers
Question 1: In AIS 2005 Update coding, an isolated spinous process fracture of T6 without associated injury is best coded as:
- AIS 1 (Correct answer)
- AIS 2
- AIS 3
- AIS 4
Correct answer: AIS 1
Isolated spinous or transverse process fractures without instability or neurological deficit are coded AIS 1 (minor) in the spine region.
Question 2: A 'Jefferson fracture' refers to a burst fracture of which vertebra and is coded in which AIS body region?
- C2, coded in Head region
- C1, coded in Spine region (Correct answer)
- C3, coded in Neck region
- C1, coded in Head region
Correct answer: C1, coded in Spine region
A Jefferson fracture is a C1 (atlas) burst fracture and is coded under the Spine body region in the AIS.
Question 3: When coding a T12 chance fracture (flexion-distraction injury) in an unrestrained rear passenger, the coder should assign a severity of at least:
- AIS 1
- AIS 2
- AIS 3 (Correct answer)
- AIS 5
Correct answer: AIS 3
Chance fractures are unstable flexion-distraction injuries typically coded AIS 3, with higher codes if neurological deficit is present.
Question 4: Which of the following BEST describes the role of CT imaging in AIS spine injury coding accuracy?
- CT is discouraged; plain films are the AIS standard
- CT provides superior fracture characterization enabling more precise AIS code selection (Correct answer)
- CT findings must be confirmed by MRI before coding
- CT changes are not reflected in AIS severity codes
Correct answer: CT provides superior fracture characterization enabling more precise AIS code selection
CT imaging reveals fracture morphology, degree of canal compromise, and instability that allows coders to select the most accurate AIS severity level.
Question 5: A patient has both a C6 fracture (AIS 3) and an L3 fracture (AIS 2). When computing the ISS, these injuries both fall under the Spine body region. How are they handled?
- Both scores are summed before squaring
- Only the higher AIS code (AIS 3) represents that body region in ISS calculation (Correct answer)
- Both are excluded from ISS
- Each region gets a separate ISS contribution
Correct answer: Only the higher AIS code (AIS 3) represents that body region in ISS calculation
For ISS purposes, only the single highest AIS severity code within a body region contributes to that region's score; multiple injuries in the same region do not add together.
Question 6: Sacral fractures involving the sacral nerve roots with neurological deficit are coded in which body region under the AIS?
- Pelvis/Extremity region
- Spine region (Correct answer)
- Abdomen region
- Pelvis — separately from spine
Correct answer: Spine region
Sacral fractures with neurological involvement are coded in the Spine body region because they involve the spinal neural axis.
Question 7: In crash reconstruction for AIS trauma research, 'delta-V' is relevant to spinal injuries because:
- Higher delta-V correlates with increased probability of severe spinal injury (Correct answer)
- Delta-V determines the exact AIS code assigned
- Low delta-V crashes never produce spinal injuries
- Delta-V is used only for head injury prediction
Correct answer: Higher delta-V correlates with increased probability of severe spinal injury
Delta-V (change in vehicle velocity) is a biomechanical crash severity metric that correlates statistically with the probability and severity of occupant spinal injuries.
CAISS Spine Injuries 3
In AIS 2005 Update coding, an isolated spinous process fracture of T6 without associated injury is best coded as: