Spine Classifications

Question 1

Cervical Myelopathy

Answer 1

Ranawat
Class I Pain, no neurologic deficit
Class II Subjective weakness, hyperreflexia, dyssthesias
Class IIIA Objective weakness, long tract signs, ambulatory
Class IIIB Objective weakness, long tract signs, non-ambulatory

Question 2

Spine Injury

Answer 2

ASIA Impairment Scale
A Complete No motor or sensory function is preserved in the sacral segments S4-S5.
B Incomplete Sensory function preserved but not motor function is preserved below the neurological level and includes the sacral segments S4-S5.
C Incomplete Motor function is preserved below the neurological level, and more than half of key muscles below the neurological level have a muscle grade less than 3.
D Incomplete Motor function is preserved below the neurological level, and at least half of key muscles below the neurological level have a muscle grade of 3 or more.
E Normal Motor and sensory function are normal.

Question 3

Lenke Classification

Answer 3

1. Curve type
2. Sagittal Modifier
3. Lumbar Modifier

Question 4

Spondylolisthesis

Answer 4

Myerding
Grade I	< 25%
Grade II	25 to 50%
Grade III	50 to 75% (Grade III and greater are rare in degenerative spondylolithesis)	  
Grade IV	75 to 100%	  
Grade V	Spondyloptosis (all the way off)

Question 5

Types of Spondylolisthesis

Answer 5

Wiltse-Newman Classification
Type I • Dysplastic: a congenital defect in pars
Type II-A • Isthmic - pars fatigue fx

Type II-B • Isthmic - pars elongation due to multiple healed stress fx

Type II-C • Isthmic - pars acute fx
Type III • Degenerative: facet instability without a pars fx
Type IV • Traumatic: acute posterior arch fx other than pars
Type V • Neoplastic: pathologic destruction of pars

Question 6

Odontoid Fractures

Answer 6

Type I Oblique avulsion fx of tip of odontoid. Due to avulsion of alar ligament. Although rare, atlantooccipital instability should be ruled out with flexion and extension films.

Type II Fx through waist (high nonunion rate due to interruption of blood supply).

Type III Fx extends into cancellous body of C2 and involves a variable portion of the C1-C2 joint.

Question 7

Thoracolumbar #

Answer 7

TLICS
Morphology

0 No abnormality
1 Compression
2 + Burst fracture
3 Rotation/translation
4 Distraction

Posterior Ligamentous complex (PLC)

0 Intact
2 Suspected / Indeterminate
3 Injured

Neurological status

0 Intact
2 Root injury
2 Complete cord / conus medullaris injury
3 Incomplete cord / conus medullaris injury
3 Cauda equina
Treatment

TLICS =5: operative

Question 8

Atlas Fractures

Answer 8

Type I Isolated anterior or posterior arch fracture. A “plough fracture is an isolated anterior arch fracture caused by a force driving the odontoid through the anterior arch.

Type II Jefferson burst fracture with bilateral fractures of anterior and posterior arch resulting from axial load. Stability determined by integrity of transverse ligament.

Type III Unilateral lateral mass fx. Stability determined by integrity of transverse ligament.

Question 9

Subaxial spine #

Answer 9

1. Flexion-compression
2. Vertical compression
3. Flexion-distraction
   Stage 1: Facet subluxation
   Stage 2: Unilateral facet dislocation
   Stage 3: Bilateral facet dislocation with 50% displacement
   Stage 4: Complete dislocation (100% displacement)
4. Extension-compression
5. Extension-distraction
6. Lateral flexion

Question 10

AARD

Answer 10

Fielding Classification of AARD
Type I
• Unilateral facet subluxation with intact transverse ligament.
• Odontoid acts as a pivot point and there is no anterior subluxation.
• Most common and benign type.

Type II
• Unilateral facet subluxation with 3 to 5 mm of anterior displacement.
• Injured Transverse ligament
• One facet acts as pivot point and one lateral mass is displaced

Type III
• Bilateral anterior facet displacement of > 5 mm.
• Rare with higher risk of neurologic involvement or instantaneous death.
• Both lateral masses are displaced

Type IV
• Posterior displacement of atlas (C1).
• Rare with higher risk of neurologic involvement or instantaneous death