3. Case 1
37 y/o F s/p high speed MVA restrained passenger
Azam Basheer
4. Case 2
47 y/o M s/p T-bone MVA, head impact against driver-side window
Azam Basheer
5. Case 3
56 y/o s/p fall from ladder with left delt weaknessAzam Basheer
6. Epidemiology
• Represents 23-30% of all spine fractures
– Cause
• MVA 42%
• Fall 20%
• Violence 16%
– Gender
• Male 81%
• Female 19%
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7. Source: National Spinal Cord Source: National Spinal Cord Injury Statistical Center, University of Alabama at Birmingham, 2004
Annual Statistical Report, June, 2004 Injury Statistical Center, University of Alabama at Birmingham, 2004
10. Anatomy – The Ligaments
– Internal (within spinal canal):
• Tectorial membrane: thickening of PLL
• Cruciate ligament – including transverse ligament
• Alar and apical ligaments
– External
• Anterior and posterior atlanto-occipital membranes
• Anterior and posterior atlanto-axial membranes
• Articular capsules
• ligamentum nuchae
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11.
12.
13. - Transverse Occipital Lig:
-Prevents posterior
displacement of the apex
of the dens
- Accessory Atlantoaxial Lig:
-Limits axial rotation
Ligaments cont.
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14. The Barkow Ligament
- Anteromedial occipital
condyles
- Sits anterior to the
apex of dens
- Limits extension of the
dens tip
Tubbs et al. Ligaments of the craniocervical junction.
J Nsurg: Spine Vol 14 / June 2011
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15. Vertebral Artery
• Arises from subclavian artery
• Enters foramen
transversarium at C6
• Turns laterally at C2
• Travels posteriorly at C1
(vertebral groove)
• Ascends superiorly along
clivus
http://www.maitrise-
orthop.com/corpusmaitri/orthopaedic/mo
68_laude/index.shtml
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16. Degrees of motion
Flexion
• Oc-C1 is 10°
• C1-C2 is 5 °
Extension
• Oc-C1 is 25 °
• C1-C2 is 10 °
Rotation
• Oc-C1 is 0°
• C1-C2 is 45 °
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18. Steele’s Rule of Thirds
http://www.pt.ntu.edu.tw/hmchai/Kines04/KINspine/Spine.files/AAAjointSup.jpg
• 1/3 cord
• 1/3 dens
• 1/3
Subarachanoid
space/empty
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19. The Atlantodental Interval (ADI)
• First described by Hinck et al
• Used to evaluate the atlanto-
axial relationship
• Normal < 3 mm in men; <2.5
mm in women; <5 mm in
children under 9
• Enlargement of the predental
space points to injury of the
transverse ligament
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20. Posterio-atlanto Dens Interval
(PADI)
- Represents the
anteroposterior diameter
of the spinal canal at this
level
- More useful
prognosticator in
rheumatoid arthritis
patients than the ADI
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21. Harris lines
- Used to evaluate osseous relationships at the
craniocervical junction
– Basion-Dens Interval: In 95% of adults, the basion-
dens interval <12 mm
– Basion–Posterior Axial Line Interval: in 98%, the
basion was situated no more than 12 mm anterior or
4 mm posterior to the posterior axial line
• “Rule of Twelve” Azam Basheer
22. Harris Lines
An abnormal distance between the dens or posterior axial line and the basion
suggests failure of the alar ligaments, tectorial membrane, or both.
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23. • First described by Powers et al, 1979
• Basion-Post. C1 arch divided by
Opisthion-Ant. C1 arch
– >1 considered abnormal
• Limited Usefulness
• Positive in Anterior Translational
injuries
• False Negative with pure distraction
Powers’ Ratio
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26. Imaging
• MR imaging of the cervical spine with T2-
weighted fat-suppressed gradient-echo or
STIR sequences useful in assessing the integrity
of ligaments.
Warner et al. Magnetic resonance imaging of ligamentous injury of the cervical spine. Emerg Radiol
1996; 3:9–15.
Dickman et al. Magnetic resonance imaging of the transverse atlantal ligament for the evaluation of
atlantoaxial instability. J Neurosurg 1991; 75:221–227.
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30. AOD
• Aka Craniocervical Dissociation, “internal decapitation”
• Cause of death in ~10% of fatal c-spine injuries
• Due to rupture of the alar ligaments, the tectorial membrane,
and the occipito-atlantal joint capsules
• May cause a SAH at the CCJ
• Mechanism:
• flexion and distraction
• rotation and hyperextension
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31. AOD
• Established criteria for diagnosis of AOD:
– BDI >12 mm, or
– BPALI >12 mm posterior to basion, or
– BPALI >4 mm anterior to basion
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32. Traynelis Classification of AOD
Type I Type II Type III
anterior subluxation
most common
vertical distraction
>2 mm of the
atlanto-occipital joint
posterior dislocation
rarely reported
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33. AOD Treatment
• AVOID traction
• Halo until surgery
• 1º treatment:
– Oc-C2 or C3 fusion
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35. Occipital Condyle Fractures
• First described in 1817 by Sir
Charles Bell at an autopsy of a
fall victim
• Associated with some C1 fx and
palsies of lower cranial nerves
• Hypoglossal n. most often
involved due to fx extension
through the hypoglossal canal
• Anderson and Montesano
(1988) classification Anderson et al., SPINE, 1988
Tuli et al., Neurosurgery, 1997
Sir Charles Bell
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36. Type I
-An impaction-type fx due to axial
loading resulting in a
comminuting fracture of the
occipital condyle
- Stable because the tectorial
membrane and alar ligament are
intact
- Collar 6-8 weeks
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37. Type II
- A basioccipital fracture,
that extends to the
condyle
- Due to a direct blow to
the skull
- An intact tectorial
membrane and alar
ligaments preserve
stability
- Collar 6-8 weeks
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38. Type III
• avulsion fx at the site of the
alar ligament resulting in
fragment displacement into the
foramen magnum
• Due to forced rotation, usually
combined with lateral bending
• Potentially unstable – due to
ligamentous disruption
• Minimally displaced Halo
vest, 8-12 weeks
• Displaced O-C2 fusion
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40. Fractures of C1
Account for 3-13% of C-spine fractures
Four types of atlas fractures
Type I:
- Isolated fractures of the anterior arch of C1
anterior arch fractures
- Usually avulsion fx
- low morbidity and little clinical
significance
- Plough fractures
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41. Plough Fracture
- Displaced fx of the anterior arch
- Hyperextension shears off the
anterior arch, a mechanism that
has been likened to a plough
- Can be associated with AOD
- Reduction with halo in slight
flexion or Oc/C1-C2
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42. Fractures of c1
Type II:
- Isolated fractures of the posterior arch
of C1
- Typically caused by hyperextension
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43. Fractures of c1
Type III:
- fracture through the lateral
mass of C1
- rotation or lateral flexion forces
- Radiographically, asymmetric
displacement of the lateral
masss
- low morbidity and little clinical
significance.
- C-collar if ligament intact vs.
halo
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48. Types of C2 Fractures
Represent ~20%
of C-spine fx
http://www.nypemergency.org
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49. Odontoid Fractures
- Represent 60% of C2 fractures
- Neurological deficits in 10-20%
- Etiology Bimodal
- Young - high energy, multi-trauma
- Elderly - low energy, isolated injury
Mechanism of injury:
• Flex loading anterior displacement of dens
(more common)
• Ext loading posterior displacement of dens
(ex: fall on forehead)
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50. 2 %
50-75 %
15-25 %
Anderson and D’Alonzo classification (1974)
Odontoid Fractures
Fracture Feature Stability
Type I
Small oblique
avulsion of
upper 1/3 of
odontoid (alar
ligament)
Stable if No
AOD and TL
intact
Type II
Fracture at
junction of
dens and C2
Unstable
Type IIa
Comminuted
fracture at
base of
odontoid
Unstable
Type III
Fx through
body of C2, incl
one or both
sup articular
processes
Usually
stable
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51. Dens Fxs: Non-surgical Management
External immobilization
- Collar vs Brace vs Halo
- 45% restriction w/ conventional braces
- 75% upper cervical motion restriction w/ halo
- 10-77% non-union rate with external fixation
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52. Non-union of Type II Odontoid Fractures Treated Conservatively
AUTHOR AND YEAR NO. OF PATIENTS NONUNION RATE (%) SIGNIFICANT FACTORS
Anderson & D'Alonzo, 1974 49 36 None specified
Apuzzo et al, 1978 45 33
Age >40 yr, displacement >4
mm
Ekong et al, 1981 17 41
Age ≥55 yr, displacement >6
mm
Hadley et al, 1985 40 26
Not age, displacement >6
mm
Clark & White, 1985 106 32
Not age, displacement >5
mm
Dunn & Seljeskog, 1986 88 24
Age >65 yr, posterior
displacement
Hanssen & Cabanela, 1987 42 50
Age >72 yr, posterior
displacement
Schweigel, 1987 47 10 Not age, not displacement
Hadley et al, 1989 65 28
Not age, displacement ≥6
mm
Ryan & Taylor, 1993 35 77 Posterior displacement
Seybold & Bayley, 1998 37 29
Not age, displacement
unknown
Greene et al, 199735 88 28 Displacement ≥6 mm
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53. Non-surgical Management
• Higher risk of non-union:
– displacement > 6mm
– >6mm – nonunion rate 67%
– <6mm – nonunion rate 9%
– Posterior displacement
– Non-union rate of 70-89%
– Angulation > 100
– Age > 50
– Smoking
– Delay in diagnosis > 3 weeks
– Inability to achieve or maintain reduction
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56. Type II Dens Surgical tx
Surgery for:
– >6mm displacement (>6 mm displacement and >60 years, 85% nonunion rate)
– Age>65
– Fracture cannot be maintain by external orthosis
– Rupture of transverse ligament
Type of surgery:
-Intact transverse ligament
* Anterior Odontoid Screw fixation
-Disrupted TL
*C1-2 posterior fusion
-Transarticular screw fixation (Magerl and Steeman Cerv Spine 1987, Reilley et
al, JSD 2003)
-C1 lateral mass – C2 pars/pedicle screw
-Posterior wiring
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57. Algorithm for Treatment of Odontoid Fractures
Odontoid Fractures
Type I Type II Type III
AOD Surgery
vs
Brace/halo
MRI
TL intact
TL disrupted
Comminuted
Posterior
Fusion
No AOD
SurgeryCollar
Post fusion
Simple fx
Ant vs post fus
Brace/halo
Fails
58. Hangman’s Fracture
- AKA Traumatic spondylolisthesis
- Bilateral arch fracture of C2 (pars)
- Younger age group (Avg 38 yrs)
- Usually due to hyperextension-axial
compression forces (windshield strike)
- Neurologic injury seen in only 5-10 %
• Effendi Classification Levine &
Edwards, and Sonntag & Dickman
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59. Type I Hangman’s
• Most common
• Bilateral pars fractures with
translation <3 mm and NO
angulation
• Axial loading and then
extension
• Stable collar
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61. Type II Hangman’s
• C2-3 disc and PLL disruption
– >3 mm displacement of C2 on C3 or
– >11o angulation
• ALL generally remains intact but is
stripped from its bony attachment
• extension, and then rebound flexion
• Unstable
– Halo if reducible vs.
– posterior approach C1-C3, or
C2–C3 anterior discectomy and
arthrodesis Azam Basheer
62. Type IIA Hangman’s
• Less common
• Little to no translation, but significant <11o
angulation
• Unstable
– Halo if reducible vs.
– posterior approach C1-C3, or C2–C3
anterior discectomy and arthrodesis
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63. Type III Hangman’s
• Pars fracture with dislocation of
the C2-3 facet joints (facet
capsules are disrupted)
• Unstable
• The most common injury to be
associated with neurological
deficit
• Requires surgery
• Options: Anterior C2-3 discectomy
and fusion, or posterior open
reduction and C1-3 fusion Azam Basheer
65. Surgical Approaches to C1-2
fusion
• Anterior odontoid screw fixation
• Posterior bone and wire fusion
• Posterior transarticular screw fixation
• Posterior fusion with lateral mass
screws/rods
• Posterior fusion with pedicle screws/rods
• Posterior fusion with translaminar
screws/rods
• Anterior transfacetal screw fixation
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66. Anterior vs Posterior
Approach for Dens fx
• Posterior fusion eliminates atlantoaxial
rotation, usually noticeable by patient
• Odontoid screw fixation: provides immediate
stabilization, promotes bone healing,
preserves C1-2 rotation
• Anterior approach more morbid due to
extensive neck dissection
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67. Anterior Odontoid Screw Fixation
Indications
• Type II and Shallow Type III
• Unable to tolerate halo-vest
• Early displacement despite halo-vest
Contraindications
• Non-reducible odontoid fracture
• Body habitus (Barrel chest )
• Associated Transverse ligament injury
• Subacute injury (> 6 months)
• Reverse oblique
• Relative contraindications: smoking, age >60
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68. Surgical Approach
• Prone
• Shoulder roll
• Halter traction
• Head extended
vs neutral
Apfelbaum RI: Anterior Screw Fixation of Odontoid Fractures (Aesculap Scientific Info 24). Tuttlingen, Germany, Aesculap AG, 1992. 51a. Apfelbaum RI, Lonser RR,
Veres R, et al: Direct anterior screw fixation for recent and remote odontoid fractures. J Neurosurg 93(2Supp):227-236.
69. Surgical Approach
• Low cervical incision (C5-6)
• Standard approach to C-
spine
• Angled retractor to create
tunnel to C2
• K-wire placed on ant-inf lip
of C2
• 8mm hand-operated hollow
drill over K-wire
• Trough in body of C3
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70. Surgical Approach
• Drill guide system over K-wire
• Spike on outer tube impacted into C3
• K-wire removed and replaced with drill
• Drill to apex of odontoid
• place screw
• Stabilization confirmed by flex/ext of neck
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72. POSTERIOR WIRING
TECHNIQUES
• Require intact posterior arch of C1 and C2
• Contraindicated
– Posterior decompression of C1-C2 required
– Significant osteoporosis
– Rheumatic involvement of the atlas
– Posterior rachischisis
• Requires sublaminar passage of a cable
– Potential for injury to Dura or spinal cord
– Need for long term post-op halo immobilization
– Requirement for intact posterior vertebral elements
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73. Interspinous Wiring
Technique originated by
Rogers, modified by Whitehill,
Benzel, Kesterson, and Murphy
and Southwick.
Bone graft between C1 and C2
laminae.
C1: wire passed though drilled-
out holes in posterior tubercle
C2: wire passed beneath SP
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74. GALLIE FUSION
Posterior interspinous fusion with
sublaminar wires and iliac grafts
Median autograft from iliac crest notched
over the spinous process of C2
Sublaminar wire placed around the
posterior arch of C1and wraps around
the spinous process of C2
Stabilization
– Comparable stabilization in A/P
translation in response to flexion
– Poor stabilization in rotation
• Patients require increased post-op
external immobilization
• Successful fusion rate 75%
http://emedicine.medscape.com/article/1343720-media
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75. Brooks-Jenkins Fusion
• Modification to overcome
the rotational deficiencies of
Gallie Fusions
• Bilateral interlaminar bone
grafts
• Requires passage of
bilateral sublaminar cables
beneath C1 and C2
• Fusion rate ~ 93%
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76. SONNTAG’S MODIFIED GALLIE
FUSION
• Decreases risk of cord injury at
C2 by eliminating sublaminar
wires
• Single bicortical bone graft fit
into interlaminar space
• Requires widening of C1-2
interlaminar space
• Pt kept in halo pre-op, intra-op,
and post-op halo for 3 months
• Fusion rate ~ 97%
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77. LOCKSLEY INTERSEGMENTAL TIE-
BAR TECHNIQUE
• 3 point fixation with immediate
rigidity and resistance to all
axis of movement
• Grafts secured with sublaminar
wires in figure-8 pattern
• Posterior stabilization plate
Secured by wires to post.
Spinous process
• Can be applied to any cervical
segment
• Rib graft is ideal, but iliac
autograft can also be used
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78. Facet/Transarticular Wiring
Useful when the posterior elements
are unavailable Callahan (1977).
1.Expose lateral masses
2.Remove facet capsular ligaments
3. Drill hole perpendicular to interior
articular process at C1 and C2
4. Wire or cable is passed in a
rostral-to-caudal direction and exits
through the joint space.
5. The wires are wrapped around
bone graft and fastened. The caudal
end of the bone graft can be
secured to the spinous process,
thus sparing the caudal facet joint.
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79. Interlaminar Wiring
- Bilateral placement of interlaminar
clamps Tucker, 1975.
- Requires intact laminae; May increase
canal stenosis--> neurologic injury
-Good stability with
flexion/extension
-Poor rotational stability
- Laminae thinned bilaterally to augment
the interlaminar spaces.
- Strut graft placed between the spinous
processes to prevent hyperextension
and promote fusion
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80. TRANSARTICULAR SCREW OF
MAGERL
• Unilateral/Bilateral
• 3.5mm screw through the C2 pedicle,
across the C1-2 facet, and into lateral
mass of C1
• C1 and 2 become rigidly coupled
• Wire passed around posterior arch of
atlas for gentle retraction on atlas
• Entry point 2mm lateral and 2mm
above the medial aspect of C2 inferior
facet
• Trajectory of the drill exits C2 at
posterior edge of superior articular
surface near the isthmus of the pedicle
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81. TRANSARTICULAR SCREW OF
MAGERL
• Post-Op
– Hard collar for 6 weeks
• Stability
– Successful fusion rates between 86.9-100%
– Construct stable in F/E and rotation
• Complications
– Madawi et al.
• Malpositioned screws in 14%
• Vertebral artery injury in 8%
• Hardware failure in 4%
• Temporary hypoglossal nerve paresis in 2%
• Iliac crest donor site infection in 2%
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82. Posterior C1-2 Fusion with
Lateral Mass Screws
• Useful when posterior
elements absent or
disrupted
• biomechanically better
rotational stability at
facets vs wiring
• Immediate rigidity
-better fusion
-no halo
Harms J, Melcher RP. Posterior C1–C2 fusion with polyaxial screw and rod fixation. Spine 2001;26:2467–71.
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83. GOEL’S/HARM’S TECHNIQUE
• Fixation using
independently placed
screws into the C1 lateral
mass and C2 pedicles,
connected with posterior
rods or plates
• Goel originally developed
the technique using
monoaxial screws and
plates, but Harm later
modified the procedure to
use polyaxial screws and
rods
Mummaneni, P. et al. Atlantoaxial fixation: overview of all techniques.
Neurology India. December 2005. Vol 53, Issue 4. 408-415
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84. GOEL’S/HARM’S TECHNIQUE
• Exposure
– Midline incision from suboccipital to
spinous process of C3
– C2-C3 facet joint and C1 posterior
arch exposed
– Vertebral artery in vertebral groove
on superior aspect of C1 arch
– Medial wall of C1 lateral mass is
medial limit for screw
– Medial aspect of transverse
foramen is lateral limit
• Entry point
– center of C1 lateral mass
– 3-5 mm lateral to medial lateral
mass
Mummaneni, P. et al. Atlantoaxial fixation: overview of all techniques. Neurology
India. December 2005. Vol 53, Issue 4. 408-415
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85. Posterior C1-2 Fusion with
Pedicle Screws
• Abumi, et al. (1994) : cervical pedicle
screws
• 3 column fixation
• Biomechanically superior to lateral
mass screws
• Enter lateral to center of facet, close
to post margin of superior articular
surface
• The angle can vary from 25 to 45°
medial to the midline
• slightly cephalad direction for the
pedicles of C-2 to C-4
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86. Posterior C1-2 Fusion with
Translaminar Screws
• First presented in 2003
• Technique published in
2004
• Minimize injury to
vertebral artery
• Crossing, bilateral
translaminar screws
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87. WRIGHT TECHNIQUE
• Open a cortical window at the
junction of the C2 spinous process
and lamina
• Insertion of polyaxial screws into
the laminae of C2 in a bilateral
crossing fashion
• The C1 lateral mass screws are
connected to the crossing,
bilateral C2 laminar screws with
posterior rods
– Safer rigid fixation of C2
– Low risk to vertebral
arteries
– Requires intact posterior
elements of C2
C1
C2
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88. Case 1
37 y/o F s/p high speed MVA restrained passenger
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91. Case 3
56 y/o s/p fall from ladder with left delt weakness
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92. References
•Anderson LD, D'Alonzo RT: Fractures of the odontoid process of the axis. J Bone Joint Surg Am 56:1663-1674, 1974.
•Clark CR, White AA III: Fractures of the dens: A multicenter study. J Bone Joint Surg Am 67:1340-1348, 1985.
•Wright et al. Vertebral artery injury in C1-2 transarticular screw fixation. J Neurosurg. 8, 1998
•Dunn ME, Seljeskog EL: Experience in the management of odontoid process injuries: An analysis of 128 cases. Neurosurgery 18:306-310, 1986.
•Ekong CE, Schwartz ML, Tator CH, et al: Odontoid fracture: Management with early mobilization using the halo device. Neurosurgery 9:631-637, 1981.
•Greene KA, Dickman CA, Marciano FF, et al: Acute axis fractures: Analysis of management and outcome in 340 consecutive cases. Spine 22:1843-
1852, 1997.
•Hadley MN, Browner CM, Liu SS, et al: New subtype of acute odontoid fractures (type IIA). Neurosurgery 22:67-71, 1988.
•Hadley MN, Dickman CA, Browner CM, et al: Acute axis fractures: A review of 229 cases. J Neurosurg 71:642-647, 1989.
•Hanssen AD, Cabanela ME: Fractures of the dens in adult patients. J Trauma 27:928-934, 1987.Winn, Richard. Youmans Neurological Surgery. 5th
edition.
•Ryan MD, Taylor TK: Odontoid fractures: A rational approach to treatment. J Bone Joint Surg Br 64:416-421, 1982.
•Seybold EA, Bayley JC: Functional outcome of surgically and conservatively managed dens fractures. Spine 23:1837-1846, 1998. Menendez et al.
Techniques of Posterior C1-C2 Stabilization. Neurosurgery 60:1, 2007
•Vender et al. The evolution of posterior cervical an occipitocervical fusion and instrumentation. Neurosurgical Focus 16:1, 2004
•Poliaksiyal et al. Posterior atlantal lateral mass fixation technique with polyaxial screw and rod fixation system. Turkish neurosurgery 18:2, 2008
•Dickman et al. Biomechanical characteristics of C1-2 cable fixations. J Neurosurg. 85, 1996
•Goel et al. Plate and screw fixation for atlantoaxial subluxation. Acta Neurochir. 129
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93. References cont.
• Hanson et al. Anatomic and biomechanical assessment of transarticular screw fixation for atlantoaxial instability. Spine 16, 1991
• Magerl et al. Stable posterior fusion of the atlas and axis by transarticular screw fixation. Spine. 1987
• Paramore et al. The anatomical suitability of C1-2 complex for transarticular screw fixation. J Neurosurg 85, 1996
• Vikas et al. Spine Trauma: Surgical Techniques. Springer. 2010
• Hadley MN, Browner C, Sonntag VKH: Axis fractures: A comprehensive review of management and treatment in 107 cases. Neurosurgery
17:281-290, 1985.
• Suchomel et al. Reconstruction of Upper Cervical Spine and Craniovertebral Junction. Springer, 2011
• Stulik et al. Harms technique of C1-C2 fixation with polyaxial screws and rods. Acta Chir Orthop Traumatol Cech. 2005; 72(1):22-7
• Hu et al. Posterior cervical spine arthrodesis incorporating C2 laminar screw fixation in the treatment of cervical spine injury. Orthopaedic Surgery.
2:1;32-37. 2010
• Apuzzo ML, Heiden JS, Weiss MH, et al: Acute fractures of the odontoid process: An analysis of 45 cases. J Neurosurg 48:85-91, 1978.
• Rhee et al. Modified trajectory of C2 laminar screw – double bicortical purchase of the inferiorly crossing screw. J Korean Neurosurg Soc. 43(2).
2008
• Senoglu et al. C2 intralaminar screw placement: a quantitative anatomical and morphometric evaluation. Turkis neurosurgery; 19, 2009
• Mummaneni et al. Atlantoaxial fixation: overview of all techniques. Neurology India. 53. 2005
• Song et al. Surgical treatment of craniovertebral junction instability: clinical outcomes and effectiveness in personal experience. J Korean
Neurosurg 48, 2010
• Warner J, Shanmuganathan K, Mirvis SE, Cerva D. Magnetic resonance imaging of ligamentous injury of the cervical spine. Emerg Radiol 1996;
3:9–15.
• Dickman CA, Memourian A, Sonntag VKH, Drayer BP. Magnetic resonance imaging of the transverse atlantal ligament for the evaluation of
atlantoaxial instability. J Neurosurg 1991; 75:221–227.
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