This document discusses different types of C2 fractures including odontoid fractures, hangman's fractures, and other C2 fractures. It describes classification systems for these fractures and outlines treatment approaches including non-operative immobilization or operative stabilization depending on the fracture type, stability, displacement, and patient factors. Surgical options involve anterior odontoid screw fixation or posterior wiring/fusion techniques. Outcomes and considerations for each approach are provided.

1. C2 FRACTURE
Dr SAMEEP KOSHTI

3. Introduction
• Odontoid fractures are
• among the most common fractures of the spine in general
• account for approximately 20 % of all cervical fractures.
• They represent 75% of childhood cervical spine fractures
• as a result of the large ratio of head to body size.
• Anderson and D’Alonzo type II fractures comprising
• around 2/3–3/4 of dens fractures.

4. TYPES
• ODONTOID FRACTURE
• HANGMAN FRACTURE
• MISCELLANEOUS C2 FRACTURE

7. Odontoid fracture by Anderson and D’Alanzo
• type I
• rare
• fracture of the upper part of the odontoid peg
• above the level of the transverse band of the cruciform ligament
• usually considered stable
• High union rate
• Conservatively managed
• type II
• most common
• fracture at the base of the odontoid
• below the level of the transverse band of the cruciform ligament
• unstable
• high risk of non-union
• In 5 % cases : Comminuted fractures
• Very unstable
• Require posterior fusion of C1 and C2
• type III
• through the odontoid and into the lateral masses of C2
• relatively stable if not excessively displaced
• best prognosis for healing because of the larger surface area of the fracture

8. The Roy-Camille classification of fractures of the
odontoid process of C2
• depends on the direction of the fracture line 1.
• This classification scheme aids the management of odontoid fractures.
• In general anterior oblique fractures are more stable than the posterior oblique
fractures.
• Classification
• type I: oblique linear fracture in which its line slopes forward, with dens displacement in
an anterior direction
• type II: oblique linear fracture in which its line slopes backward, with dens displacement
in a posterior direction
• type III: horizontal fracture line and the dens displacement can be either anterior or
posterio

9. TYPE II Odontoid fracture
subdivided into three types by Hadley et al:
• Type IIA:
• The fracture line is transverse and
• less than 1.0 mm of displacement.
Mx:
Both surgery and external immobilisation have good success rates.
The treatment strategy has to be decided based on the individual merits of the case
• Type IIB:
• The fracture line is from antero-superior to postero-inferior or
• a transverse fracture with displacement greater than 1.0 mm.
• MX:
Surgical fixation is the treatment of choice
• Type IIC:
• The fracture line passes from antero-inferior to postero-superior or
• a fracture with significant comminuted segments of the dens.
• Mx:
best treated with posterior atlantoaxial fixation.
Because ,the fractured odontoid process may be displaced anteriorly or posteriorly relative to the body of C2.
Odontoid screw placement in these fractures is technically difficult and also the non-union rates are high.
Posterior fixation is a good option in this group of patients

12. Levine and Edwards classification is used to classify hangman
fractures of C2 (also known as traumatic spondylolisthesis of
axis).
• type I: fracture with <3 mm antero-posterior deviation
• no angular deviation
• type II: fracture with >3 mm antero-posterior deviation
• significant angular deviation
• disruption of posterior longitudinal ligament
• type IIa: the fracture line is horizontal/oblique (instead of vertical)
• significant angular deviation without anterior translation
• type III: type I with bilateral facet joint dislocation

14. Effendi’s classification system, modified by Levine and Edwards,
for traumatic spondylolysis of the C2 isthmus (hangman’s
fracture) (BENZEL)
• Type I is a fracture with a
• normal C2-3 intervertebral disc and
• less than 3-mm displacement without angulation
• Type II is a fracture consisting of
• disruption of the C2-3 disc space and
• ventrally angulated or displaced fractures.
• Type III is a fracture that involves ventral displacement with
hyperflexion of the axis associated with unilateral or bilateral facet
dislocations.

15. MISCELLANEOUS C2 FRACTURES
• C-2 lamina,
• spinous process
• facets and
• lateral mass,
• MANAGEMENT:
• these may require external immobilisation or Halo immobilisation, if unstable.

16. MANAGEMENT OF ODONTOID FRACTURES
• many treatment strategies
• are based on
• Fracture type,
• the degree of initial dens displacement,
• The angle of the fracture line with respect to the body of the axis,
• the integrity of the transverse ligament and
• The age of the patient.

17. TYPE I ODONTOID FRACTURE
• considered stable (unless they are associated with instability involving
the occipitocervical junction) and
• may be treated with a Philadelphia collar or similar orthosis.
• Fusion rate : 84-88 % with immobilization

18. TYPE III ODONTOID FRACTURE
• Type III fractures are often successfully managed with collar or halo
immobilization.
• Fusion rate also same as type 1 fracture:
• 84-88 %

19. Non union of type 2 odontoid fracture
• An increased rate of nonunion has been associated with
• patients older than 50 years,
• subluxation greater than 4 to 6 mm, and
• dens displacement greater than 5 degrees after closed reduction.
• Other factors
• Angulation,
• loss of fracture reduction, and
• medical comorbidities. Surgical stabilization, when chosen, may proceed through a ventral or
dorsal approach, depending on patient variables and fracture subtype
• Nonunion rates can be as high as 28%.
• Type II fractures, lack both periosteum and cancellous bone at the fracture site,
increasing the propensity for nonunion.

20. • Fractures that are significantly displaced
• may be realigned with traction-reduction and immobilized with a halo vest until definitive
measures are taken.

21. • Non Operative
• External immobilization orthoses
• Operative
• Anterior approach
• Posterior approach

22. SURGICAL MANAGEMENT
• First time
• as early as 1980 by Nakanishi and
• in 1982 by Bohler,

23. ANTERIOR APPROACH
• include
• Odontoid screw fixation and
• a rarely used salvage technique of anterior transarticular screw fixation.

24. ODONTOID SCREW PLACEMENT
• In appropriately selected young patients the success rates of direct
odontoid osteosynthesis
• via an anterior screw can be as high as 90 % in terms of good functional
outcome

25. INDICATION FOR ODONTOID SCREW
• Type II and “shallow” or rostral type III fractures (Anderson and
D’Alonzo)

27. • Type IIA fractures (comminution of the dens)
• might not warrant sufficient screw purchase,
• which is particularly important at the cortical tip of the dens that needs to be engaged by
the screw.
• MRI CERVICAL SPINE:
• Particular attention to the state of the transverse ligament should be paid.
• In case of a clear rupture this would represent a contraindication to odontoid screw fixation.

28. TIMING OF SURGERY
• The general rule “The earlier you fuse, the better”
• Evidence from the literature seems to suggest that
• there are no differences in fusion rates during the first 6 months,
• whilst after 18 months fusion rates drop clearly.
• So,time can be bought for conservative management for odontoid
fracture.
• Immedicate screw fixation vs upto 6 months ????

29. Age
• Young age :
• Better union and fusion by immobilization
• Age over 50 yrs
• Non union rates 21 times higher

30. Technique of screw placement
• Position and setup
• Non armoured tube for ventilation
• Supine
• Head neutral and immobilized
• Two C-arms : AP and Lateral
• If Dislocation presents:
• Head manipulation till desired position under C-arm
guidance
• Pharyngeal pressure +/-
• Open mouth view:
• Mouth opener / bite blocks
• Check reduction
• Drapping

33. Screw insertion site
• skin incision
• is made roughly at the level of C5,
• extending from the midline to slightly beyond the medial border of the
sternocleidomastoid, usually on the right side of the patient or according to
surgeon preference.
• Subplatysmal dissection and application of retractors
• Identical to cervical discectomy

35. • C2 is palpated
• the craniocaudal self retaining retractor blades are inserted.
• Under fl uoroscopic control a
• K-wire is inserted through the incision and advanced to the anteroinferior border of C2 and
impacted with amallet
• On the anteroposterior plane
• the K-wire should sit in the centre of the odontoid process,
• on the lateral view,
• it should already be angulated in a way that its projection will go through the major axis of the dens and
penetrate its posterior half.
• The central position
• Due to insertion of a single screw
• experience and the literature that insertion of two screws offers no advantage.

36. • DRILL GLUIDE
• slide a cannulated drill guide over it and anchor it on the cervical spine
• Measure depth of penetration

37. SCREW INSERTION
• Screw diameter should be
• 4.5 mm single or
• Double 3.5 mm
• screw design two types:
• lag screws and
• fully threaded screws
• Lag screws are indicated in the majority of cases as due to :
• their conformity they deliver the possibility to reduce and compress a fracture fragment,
• as once the screw head is engaged against the inferior borderof C2 the threaded part will continue to deliver
the fragment downwards upon turning with the whole of the screw, however, not changing position anymore.
• C/I of lag screw:
• anteroinferior oblique fracture line of the dens,
• as the compression can lead to malalignment of the fracture.

39. • Make sure that the screw
• engages and traverses the cortex of the fractured dens fragment.
• A protrusion of the screw
• a couple of millimeter beyond the dens cortex is safe and mandatory for good purchase and to avoid
later screw pullout.

41. POSTOPERATIVE CARE
• COLLAR UNNECESSARY
• In a fracture fi xed with a
• lag screw of the correct length,
• appropriately traversed the dens cortex
• and offers good purchase in a
• good quality bone,
• RIGID CERVICAL COLLAR REQUIRED
• less good purchase in a
• Non compliant patient
• would probably warrant immobilization in a rigid cervical collar for 6–8 weeks.

42. POSTERIOR APPROACH
• Posterior wiring and clamps
• Original (Gallie’s technique) Single graft (LEAST BONE FUSION ) (60-80%)
• Brooks and Jenkins (Double graft)
• Dicakman and Sonntag (Graft with sublaminar wire)

43. • Trans Articular screw fixation of C1-C2 (JEANNERET and MAGERL)
• described by Magerl and Seeman HIGHEST BONE FUSION (95-100%)
• The entry point
• on C2 is 2 mm lateral from the medial edge of the facet and 3 mm superior to the caudal edge.
• The trajectory is
• straight up across the C1 and C2 articular surfaces and into the lateral mass of C1.
• The drill is aimed at the superior portion of the C1 anterior arch
• lateral medial inclination of about 0–10°.
• Trajectory should be a little superior to the anterior tubercle.
• The drilling is stopped 3–4 mm before reaching the anterior tubercle,
• preventing penetration of the retropharyngeal space and a
• cannulated screw is then screwed on the K-wire.
• avoid the advance of the K-wire while the screw is positioned.

46. C1LM-C2PS fixation
• first described by Goel and Leheri in 1994
• but gained popularity after its reappraisal by Harms and Melcher
• ADVANTAGE:
• the integrity of the posterior arch of C1 is not needed and
• also alignment of the axis is not necessary.
• reduction and alignment of the C1-C2 complex can be obtained also in many cases
considered non reducible at the pre-operative studies

47. Technique
• The entry point for the C1 screw is :
• in the center of the lateral mass or
• at the union of the posterior arch with the lateral mass.
• In order to avoid conflict with the C2 nerve root,
• a little portion of the inferior aspect of C1 posterior arch can also be removed by drilling or rongeurs.
• No drilling
• should be made above the junction of the posterior arch with the lateral mass because this area is
too close to the vertebral artery.
• Under fl uoroscopy a
• hole is drilled with a direction from 0° to 25° medially toward the anterior tubercle
• After tapping:
• the hole a screw (3.5 mm) is positioned.

48. • C2 Entry point :
• Pars
• The entry point and the direction of the screw are
• about the same as in the transarticular technique
• (3 mm medially and 3 mm superiorly to the articular surface of C2
• toward the anterior tubercle) with a
• latero-medial angulation of 15°.
• Pedicle
• The pedicle of C2 is located anteriorly to the pars and
• trajectory is
• a little less angulated (about 20° on a sagittal plane and 15° medially).
• The entry point of a C2 pedicular screw is very little (about 2 mm) superior and more medial than the entry
point for screwing the C2 pars.

54. HANGMAN’S FRACTURE
• Type I fractures
• treated with immobilization in a cervical orthosis for 3 months.
• Type II fracture
• Fracture reduction may be achieved with skeletal traction in extension with
• immediate or delayed conversion to halo-vest immobilization.
• Decreased fusion rates were found for type II fractures with an angulation of 12 degrees
or more,
• requiring an extended period of traction to ensure proper alignment before long-term fixation with halo
immobilization.

55. IN CASE OF NON HEALING TYPE II HANGMAN’S FRACTURES
• In reducible fractures,
• a primary screw fixation of the pars articularis has been performed with good realignment
and fusion.
• In fractures that are not anatomically reducible, or in cases of displaced
nonunion,
• ventral C2-3 arthrodesis can be considered.

56. TYPE II A fracture
• Reduction is by
• extension and slight axial loading;
• axial traction will accentuate the deformity.
• Reduction should be followed by immobilization
• in a halo vest for 3 months.

57. TYPE III FRACTURE
• The critical feature is the classic presence of a free-floating dorsal
arch of C2.
• These are unstable and irreducible by closed means, requiring surgical
intervention