Subaxial Trauma

 Atlanto-Occipital Dislocation (C0-C1) (AOD)

• 3 types:

  • Type 1=anterior subluxation

  • Type 2= distraction

  • Type 3=posterior subluxation (rare)

• Evaluation:

  • C1-Condylar Interval (CCI) seems to be best. This should not exceed 1.5mm.

  • Occipital condyle to the superior facet should be <5mm

  • BDI should be <5 mm and <10 mm in children

  • Power's ratio: Anterior basion to posterior arch of C1/Opisthion to anterior arch >1 = injury

Treatment:

• ABC's. Think respiratory compromise

• Evaluate for associated vertebral artery dissection (CTA)

• Halo immediately

• Stabilize with O-C3 fusion

  • Occipital plate

  • Usually skip C1

  • C2 pedicle screw

  • C2 pars screw

  • Subaxial screw technique

• Special Circumstances

  • If condylar compression on brainstem- need anterior decompression

C1 Fracture

• Morphology:

  • Single arch fracture

  • Burst fracture (2, 3, or 4 points)

  • Lateral mass fracture

• Evaluation:

  • Open mouth XR

  • CT scan with reconstruction

  • Need to assess integrity of Transverse Alar Ligament (TAL)

    • Rule of Spence: Combined >7mm lateral projection of the lateral masses of C1 on lateral masses of C2

Treatment:

• Conservative management: Miami J collar 6-12 weeks usually OK

• If unstable: Surgical Fixation or Fusion

  • C1 ORIF

  • C1-2 fusion

  • Rare: Occipital cervical fusion if multiple ring fractures

Rotary Subluxation (C1-C2 Subluxation)

• More common in pediatric population

• Etiology:

  • Trauma

  • Grisel Syndrome

• Evaluation:

  • CT Scan with recontruction

  • C1-C2 rotation with > 47 degrees

• Treatment:

  • Nonoperative. Attempt to reduce using manual traction or with Gardner Wells tongs

  • If unreducible (rare) :

    • Open reduction and internal fixation (C1-C2)

C2 Fractures

• Odontoid Fracture

  • Anderson and D’Alonzo Classification

    • Type I-Odontoid Tip

      • Rare. Avulsion fractures. Management: Miami J collar.

    • Type II- Odontoid Base

      • Common. Prone to Nonunion. Management: C1-2 Fusion.

      • Can obtain MRI to assess integrity of TAL. If intact, Odontoid Screw may be considered in younger, thinner patient to retain ROM.

    • Type III- C2 body involvement

      • If fracture pattern relatively nondisplaced, management : Miami J collar.

      • Consider CTA if fracture involves foramen transversarium.

      • Can consider C1-2 fusion in certain cases.

C2 Fractures

• Hangman Fracture (C2 Pars/Pedicle Fractures)

  • Effendi Classification

    • Type I: Fracture through the pedicle of axis

    • Type II: + Displacement of ventral fragment

    • Type III: + Facet dislocation

  • Levine and Edwards Classification

    • Type IIA: None to mild displacement, + severe angulation

  • Evaluation

    • CT scan

    • MRI to determine status of C2-3 disc.

  • Treatment

    • Type I: Cervical Collar

    • Type II: +/- reduction + Cervical Collar vs Halo

    • Type IIA: Avoid traction. Halo versus Surgery (Posterior C1-3 versus C2-3 ACDF)

    • Type III: Avoid traction. C1-3 fusion +/- C2-3 ACDF