2. • Occipitoatlantal Dislocation
• OAD is a consequence of complete or nearly
complete disruption of the ligamentous
structures between the occiput and upper
cervical spine
• High-speed motor vehicle crashes and the striking
of pedestrians by motor vehicles are the two
most common causes
• Primary mechanism in OADs is extreme hyper
extension of neck
3. • present with neurological abnormalities,
including lower cranial nerve paresis,
monoparesis, hemiparesis, quadriparesis,
respiratory dysfunction
4. • The diagnostic methods most commonly used
now include the following:
6. • Patients with CT-documented OAD are
unstable and require surgical fixation
• Dorsal fusion with rigid internal fixation that
incorporates at least the occiput to C2 is
required for an adequate construct.
• High fusion rates can be achieved with the aid
of screw instrumentation and wired structural
rib autografts or fibular allografts
7.
8.
9. • Occipital Condyle Fractures
• Anderson and Montesano classified OCFs into
three types
10. • In general, types I and II are considered stable
fractures, and patients require external
immobilization of the head and cervical region
alone.
• Type III fractures are considered unstable,
with the patient potentially requiring internal
fixation of the injury because of its
ligamentous nature
11. AAD
• Types of atlantoaxial subluxation:
• 1. rotatory: usually seen in children after a fall
or minor trauma
• 2. anterior: more ominous
• 3. posterior: rare. Usually from erosion of
odontoid. Unstable. Requires fusion
12. Atlantoaxial rotatary subluxation
• typically seen in children, associations:
trauma, RA, respiratory tract infections in peds
(Grisel syndrome)
• often present with cock-robin head position
(tilt, rotation, sl. flexion)
13.
14. • Patients are usually young. Neurologic deficit
is rare. Findings may include: neck pain,
headache, torticollis— characteristic “cock
robin” head position with 20° lateral tilt to
one side, 20° rotation to the other, and slight
10° flexion.
pathognomonic finding on AP C-spine X-ray in
severe cases: frontal projection of C2 with
simultaneous oblique projection of C1
15. • Traction
• If treated within the first few months, the
subluxation can usually be reduced with gentle
traction
Surgical fusion
• Subluxation that cannot be reduced or that recurs
following immobilization should be treated
bysurgical arthrodesis after 2–3 weeks of traction
to obtain maximal reduction. The usual
procedure is C1 to C2 fusion unless other
fractures or conditions are present
16. Anterior atlantoaxial subluxation
• One third of patients with AAS have neurologic deficit or die.
• Subluxation may be due to:
• 1. disruption (rupture) of the transverse atlantal ligament (TAL):
the atlantodental interval (ADI) will be increased
• a) attachment points of the TAL may be weakened in rheumatoid
arthritis
• b) trauma: may cause anatomic or functional ligament disruption
• 2. incompetence of the odontoid process: ADI will be normal
• a) odontoid fracture
• b) congenital hypoplasia
17. Transverse Ligament Injuries
• A distance from the posterior wall of the
anterior arch of C1 to the anterior wall of the
dens of more than 3 mm in adult patients or
more than 5 mm in pediatric patients
18. • The clinical relevance of C1 fractures resides
on the integrity of the transverse ligament.
• Spence and colleagues proposed the rule of
Spence, by which a more than 6.9-mm lateral
mass displacement of C1 over C2 on the open-
mouth radiograph suggests a transverse
ligament disruption
19. • Dickman and colleagues classified into two
categories.
• Type I are disruptions of the substance of the
transverse atlantal ligament,
• Type II are fractures or avulsions that detach
the bony tubercle that is the insertion point of
the transverse ligament at the C1 lateral mass.
20.
21. • Type I injuries are incapable of healing
because the ligament integrity is disrupted,
and patients require surgical fixation of C1-2.
• In type II injuries, the ligament is intact but
detached; patients have a 74% to 80% chance
of healing satisfactorily with external orthosis
(halo vest). Surgery can be reserved for
nonunion injuries after 3 to 4 months of
attempted immobilization.4
26. • Barrow Neurologic Institute (BNI) management guidelines for
isolated C1 fracture Evaluation: unless contraindicated, all
• patient’s are evaluated with cervical MRI to assess the integrity of
the TAL and thin-cut cervical CT to assess the fracture. Lateral mass
displacement (LMD) is measured in all cases.
• 1. Dickman Type I TAL disruption (pure ligamentous injury): surgical
fusion
• 2. the following may be treated with immobilization for 3 months
after which flexion/extension Cspine X-rays are obtained, and
surgical fusion is performed if unstable
• a) TAL intact on MRI and LMD< 7mm: cervical collar X 3 months
• b) Dickman Type II TAL disruption (bony avulsion) or LMD≥ 7mm:
halo X 3 months s
27. • Surgical options
1. unilateral ring or anterior C1 arch fractures:
C1–2 fusion
2. multiple ring fractures or posterior C1 arch
fractures: occipital-cervical fusion
30. • Type I odontoid fractures represent 1% to 3%
of all odontoid fractures.
• The mechanism of injury is considered to be
avulsion of one of the alar ligaments.
• Most authors accept that these fractures are
stable and able to be treated with external
bracing halo vest
31. • Type II is the most common odontoid fracture.
• These fractures are due to lateral bending and
extension forces.
• These fractures are generally considered
unstable; however, treatment does remain
controversial because many authors have
demonstrated significant rates of healing with
nonsurgical methods
32. • Type III is the second most common odontoid
fracture.
• This type of injury is due to pure extension.
• Most type III fractures can be successfully
treated in external braces with expected
healing rates of 87% to 100%.
34. Hangman’s fracture
• Traumatic spondylolisthesis of the axis, is the
second most common type of axis fracture.
This injury involves bilateral fracture through
the pars interarticularis of C2 with traumatic
subluxation of C2 on C3,
• most often due to hyperextension + axial
loading most are stable with no neurologic
deficit
35. Levine/Effendi classification
• Angulation is measured as the angle between
the inferior endplates of C2 and C3.
Anterior subluxation of C2 on C3 > 3mm (Type
II) is a surrogate marker for C2–3 disc
disruption, which can be evaluated more
directly with cervical MRI
36.
37. • Levine type I or Ia fractures can be treated with
collar immobilization for 3 months with high rates
of healing.
• Type II fractures usually reduce with gentle
cervical traction. Patients with these fractures
should be placed in a halo vest for 3 months.
• For fractures with more than 5 mm of
subluxation or at least 30 degrees of angulation,
surgical fixation should be strongly considered
38. • Levine type IIa fractures should be reduced
immediately in a halo vest with extension and
compression applied.
• Levine type III fractures require surgery for
stabilization and reduction
39. • hangman’s fractures may initially be managed
with external immobilization in most cases (halo
or collar)
• surgical stabilization should be considered in
cases of:
a) severe angulation of C2 on C3
b) disruption of the C2–3 disc space
c) or inability to establish or maintain alignment
with external immobilization
40. • Surgical options include anterior and posterior
approaches
C1–2 posterior wiring and fusion is an option only
if all the following are intact: C2–3 disc, C2–3
joint capsules and posterior arch of C1.
C1–3 fusion using C1 lateral mass screws & C3
lateral mass screws connected with rods (skipping
C2)
• An anterior C2-3 discectomy and fusion can
frequently treat these fractures.
44. C1–2 transarticular facet screws (TAS)
• MAGERL TRANSARTICULAR SCREW
Entry point is 2mm Lateral and 2mm Above
medial aspectOf c2 inferior facet
45. C1–2 screw fixation
• Placement of polyaxial mini screws in C1 & C2 pedicle
with rod fixation.
Advantages over C1–2 transarticular screws :
1. the more superior and medial trajectory should reduce
the risk of VA injury
2. may be used in the presence of C1–2 subluxation
3. may be usable in certain cases of aberrant VA course
4. in selected cases, this can be used for temporary
fixation without fusion (since joint spaces remain
intact) and the hardware may be removed after an
appropriate time to reclaim motion in the C1–2
articulation
46.
47.
48.
49. • GOEL/ HARM TECHNIQUE
• Fixation using independently placed screws
into c1 lateral mass and c2 pedicles connected
with rods r plates
