Subaxial Vertebral Fractures
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- No. I will decide based on the NEXUS criteria - NSAID. If any present, I will do.
- N - Neurodeficit
- S - spinal tenderness
- A - AMS
- I - Intoxication
- D - presence of Distracting injuries
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- Comment on adequacy - it should show till T1, ask for open mouth for C2 peg and AP view looking for symmetry
- 4 lines - Anterior vertebral line, Posterior vertebral line, spinolaminar line, Posterior spinous line
- Look for subluxation < 25 or > 25 % for dislocation
- Lateral view
- [Atlantoaxial dissociation] If ADI > 5mm = disruption of TAL
- If PADI < 14mm = disruption of TAL
- [Occipitocervical Dissociation] Harris rule of 12
- Basion-dens interval (tip of basion to tip of dens)
- Basion-Axial interval (perpendicular distance from basion to vertical line along the posterior dens)
- Both less than 12 (better and easier to use than Power's ratio)
- Open mouth
- Sum of lateral mass How does one determine stability of a C1 fracture?
- Soft tissue - 2662
- Normal < 6mm at C2; <2cm at C6 [2662]
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- Compression (AO Type A)
- No involvement of posterior body cortex
- Flexion Tear drop (AO Type B) ➔ Most severe (almost like a Chance 3 column Fracture)
- High energy with fracture of anterior inferior portion of vertebra
- Often a/w PLC injury, SCI, extremely unstable (Chance –type fracture ➔ bony or ligamentous
- Extension tear drop (AO Type B)
- Small fleck of bone avulsed from anterior end plate
- Burst (AO Type A)
- Posterior body cortex fractured with retropulsion
- AO Type C -Translation injury
- Type F - facet joint injuries
- Clay Shoveler’s
- Avulsion # of spinous process C6/C7/ T1 --> stable injury
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- Behaves like a Chance injury in the C-spine
- High energy flexion, compression injury of anterior
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- SubaxiaL Injury Classification by the Spinal Study Group Vaccaro et al. 2007 (SLIC)
- vs TLICS. Distraction lower than translation;
- 3 components
- Morphology
- Integrity of disco ligamentous complex (not PLC!)
- Neurological status
- Scoring/
- < 4 = Non Op
- 4 = surgeon decide
- > 4 (5 or more) = consider op
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- Principles = Decompress, Reduce, Stabilize
- Approach – anterior vs posterior
- Fusion
- Anterior – ACDF/ ACCF
- Posterior – Fusion with lateral mass screws
- KIV anterior + posterior
Halo Vest
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- Supra-axial spine to limit rotation and dlexion
- C1/2 - 50% of head rotationn
- C0/C1 = 50 % of head flexion
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- Require 3 assistants – 1 to hold, 2 to apply
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- Choose appropriate halo ring size by measuring skull circumference - should provide 1-2cm clearance around head.
- Choose appropriate vest size - measure at level of xiphoid process
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- 2 anterior pins – 1cm above orbital ridge, just beneath equator of skull at medial 2/3 and lateral 1/3 junction of orbit
- Protect supraorbital nerve
- 2 posterior pins – opposite anterior pins at 4 and 8 oclock
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- Under LA with eyes tightly closed to prevent trapping of the frontalis muscle
- Insert pins perpendicular to the skull bone, Tighten 2 diagonally opposed pins simultaneously with torque screw driver
- Tighten to 8 inch-pound torque (adults)
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- Adults – 4 pins at in-8lbs
- Children – more pins with less tourque (8-10 pins; 2 in-lbs)
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- Secure pin to vest with nuts and screws
- Check XR after placement of vest
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- Pins should be tightened carefully once a day for 3 days, then check tightness every 3 days
- Pins should not be tightened more than a full turn at any visit
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- Can be divided in the various structures involved
- Skin - infection, pressure, abrasions in vest
- nerve - abducens nerve (LR6), supraorbital nerve
- Muscle - frontalis trapped - unable to open eyes
- Artery - temporal artery
- Bone - through the skull
- Brain - injury to brain
- Failure
- Most commonly injured nerve – abducens nerve CN 6
- Others – supraorbital nerve
- Pin site infection, Dural puncture
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- Longest intra-cranial pathway
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- Traction for scoliosis
