Ajm Sheet: Ankle Fracture

1. AJM Sheet: Ankle
Fracture
Evaluation

2. AJM Sheet:
Ankle
Fracture
Evaluation
• The standard trauma work-up again applies
with primary and secondary surveys. The
following describes unique subjective
findings, objective findings, diagnostic
classifications and treatment considerations.
• Residents and attendings love to ask
questions about ankle fractures for whatever
reason, so this is certainly a subject where
you should know the classification systems
cold, and do a lot of the additional readings.
We’ll keep it brief here.

3. AJM Sheet:
Ankle
Fracture
Evaluation
• Relevant Anatomy to Review (not just for
this topic; think lateral ankle instability,
peroneal tendonopathy, sprains, etc.):

4. Ankle Ligaments:
• Lateral: ATFL, CFL, PTFL

5. Ankle Ligaments:
Medial (Deltoid):
Superficial: superficial talotibial,
naviculotibial, tibiocalcaneal
ligaments
Deep: anterior talotibial and
deep posterior ligaments

6. Syndesmotic
Ligaments:
• AITFL, PITFL (and inferior
transverse tibiofibular
ligament), Interosseous
ligament
• Bassett's ligament
represents the deep
portion of the AITFL

7. • Ottawa
Ankle Rules
Developed by ED docs to minimize unnecessary
radiographs following ankle sprains. X- ray only
required if:
1.Bone tenderness along distal 6cm of posterior
edge of fibula or tibia
2.Bone tenderness at tip of fibula or tibia
3.Bone tenderness at the base of the 5th met
4.Bone tenderness on the navicular
5.Inability to bear weight/walk 4 steps in the ED
[Stiell IG, et al. A study to develop clinical decision rules for the use of radiology in acute ankle injuries. Ann
EmergMed. 1992; 21(4): 384-90.]

8. Lauge-
Hansen
Classification

9. First submitted as a doctoral thesis [Lauge-Hansen N, Anklebrud I. 1942]. Co-authored with a guy named
“Ankle”- brud [Lauge-Hansen N. Fractures of the ankle: analytic, historic survey as the basis of new
experimental roentgenologic and clinical investigations. Arch Surg 1948; 56: 259.]
The problem with the Lauge-
Hansen classification: This was
an experimental/ laboratory
study looking at the result of
forced talar movement on a
fixed tibia-fibula. But most
ankle fractures in real-life
occur when a moving tibia-
fibula acts on a fixed foot.

10. Danis-Weber/AO Classification for lateral
malleolar fractures (From AO Group)

11. • Mueller Classification for medial malleolar
fractures (From AO group)

12. • Additional
named
fractures
associated with
the ankle:

13. • Additional
named
fractures
associated with
the ankle:

15. AJM Sheet:
Ankle
Fracture
Treatment
• Principles of Fixation:
This is one area where there is a lot of
controversy in the medical literature. There are
certainly some things you want to accomplish
besides the generic concept of “anatomic
reduction”. I can’t get too much into it in this
limited space, but I will try and give you a
couple sides of the argument and some reading
to do. The question you are really trying to
answer is: “How reduced is reduced enough?”
Then we’ll briefly cover some specific aspects of
the surgeries themselves. One thing to
appreciate is that most of these arguments are
made about SER fractures (because they are the
most common):

16. Fixation Goal:
Restore fibular
length
• Most people agree that the fibular fracture is the dominant fracture. In other words,
if you adequately reduce the fibula, then the other fractures and dislocations more or
less fall into line because of the soft tissues (poor man’s definition of the Vassal
Principle). It doesn’t mean that the other fractures don’t require fixation, but it
means there’s no real sense in fixating the other fractures unless you have the
dominate fracture fixated (or at least reduced).
• Dime sign: The most useful radiographic signs of fibular length is described on the
AP view as an unbroken curve connecting the recess in the distal tip of the fibula
and the lateral process of the talus when the fibula is out to length. A broken dime
sign represents the fibula mal-reduced in a shortened position.
• The other concept is that a fixed fibula is essentially acting as a buttress, keeping the
talus within the ankle mortise.
• The fibula is generally shortened in ankle fractures, so you want to get the full length
back with your reduction (generally visibly seen by reduction of the posterior spike on
a lateral view).
• • [Yablon IG, et al. The key role of the lateral malleolus in displaced fractures of the
ankle. JBJS-Am. 1977; 59(2): 169-173.]

17. Restore the
ankle mortise
(medial clear space and
the syndesmotic gap)
This goes back to the fibula keeping the talus in the ankle mortise. The
classic article you need to know is Ramsey and Hamilton that showed a
42% decrease in the tibiotalar contact area when the talus was
displaced 1mm laterally. From this, people inferred that if the talus isn’t
perfectly reduced back into the mortise, then gross instability occurs.
This is assessed by:
• Medial clear space: Should be ~4mm or less after reduction
• Tib-Fib Overlap: Approximately >10mm on AP view at 1cm
superior to the joint line
• Talar Tilt: <10 degrees absolute, or <5 degrees compared to
other side
[Ramsey PL, Hamilton W. Changes in tibiotalar area of contact caused by lateral talar shift. JBJS-Am. 1976;
58(3): 356-7.]
[Park SS, et al. Stress radiographs after ankle fracture: the effect of ankle position and deltoid status on
medial clear space measurements. J Orthop Trauma. 2006; 20(1): 11-18.]

19. Fix the syndesmosis?
• Another area of controversy where there is no clear
• Answer is when and how to fixate the syndesmosis with internal
fixation. One point is clear: the purpose of placing internal fixation
across the syndesmosis is to stabilize the fibula against the tibia to
prevent lateral migration of the talus and instability. If the fibula is
stable against the tibia with all of your other fixation, then you
don’t really need any additional fixation.
• How can you tell? Radiographic findings and the Cotton hook test
for instability intra-operatively.
• Other questions where people have opinions, but no clear
answers are: What type of screws? How many screws? How many
cortices? How far above the ankle? Temporary vs. permanent
fixation? Weight-bearing? etc.

20. • Lateral Malleolus:
• Fracture is primarily reduced and fixated with a single
2.7 or 3.5mm cortical screw with interfrag
compression.
• Then a generic 1/3 tubular plate or a specialized
contoured plate is used for buttress stabilization.
• • Attempt for 6 cortices proximal to fracture with 3.5
bicortical screws
• • Get as many distal screws as you can. 3.5 bicortical
if above the ankle joint. 4.0 unicortical if not.
• Proximal fibular fractures still amendable to 1/3
tubular plating, but may need to double-stack the
plates.
• Should appreciate the concept of lateral vs. posterior
anti- glide plating.

21. Medial Malleolus:
Several options including 4.0 cancellous, K-wires, plating, cerclage, etc.

22. Additional
Reading:
• - [Mandi DM, et al. Ankle fractures. Clin Podiatr Med Surg. 2006 Apr; 23(2):
375-422.]
• - [Mandracchia DM, et al. Malleolar fractures of the ankle. A comprehensive
review. Clin Podiatr Med Surg. 1999 Oct;
• 16(4): 679-723.]
• - [Kay RM, Matthys GA. Pediatric ankle fractures: evaluation and treatment. J
Am Acad Orthop Surg. 2001; 9(4):
• 269-78.]
• - [Jones KB, et al. Ankle fractures in patients with diabetes mellitus. JBJS-Br.
2005; 87(4): 489-95.]
• - [Espinosa N, et al. Acute and chronic syndesmosis injuries: pathomechanics,
diagnosis and management. Foot Ankle Clin. 2006 Sep; 11(3): 639-57.]

23. Questions and Answers

24. 1. What are the
radiographic
hallmark of
each Lauge
Hansen Injury?
• PER – high fibular fracture
• SER – spiral oblique fracture of the distal
fibula
• PAB – short oblique fracture of the distal
fibula
• SAD – short oblique fracture (near vertical)
of the medial malleolus

25. 2. What is the
big difference
between a SER
type fracture
and a PAB type
fracture?
• SER has a posterior fibular spike while a PAB
has a posterior tibial fracture

26. 3. What
fragment do
you reduce first
during ORIF of
an ankle
fracture?
• The fibular fracture

27. 4. What do the
two words of
the Lauge-
Hansen
classification
system signify?
• The first word is the position of the foot at
the time of injury.
The second word is the direction of the
deforming force or the direction the talus
moves in the mortise.

28. 5.What is the
Danis-Weber
classification
system based
on?
• The anatomic position of the fibular fracture
in relationship to the tib-fib syndesmosis

29. 6. You are called to see a
patient in the ER. The ER
nurse tells you in a stressed
out near hysterical voice
that this patient has a
transverse fracture of the
fibula and a near vertical
fracture of the medial
malleolus. What type of
fracture is she describing?
• SER 2 or Danis Weber A

30. 7. At what
stage of the
SER injury,
would you see
a Wagstaffe
fracture?
• SER 1

31. 8.When does
a posterior
malleolar
fracture need
to be
fixated?
• If the fracture involves 25 – 30% of the
articular surface

32. 9. Apply
Vassal’s
principle as it
applies to the
ankle joint.
• When you reduce and fixate the fibular
fracture to the appropriate length, the talus
should fall back into the mortise. This
doesn’t always work perfectly for the medial
malleolus.

33. 10. Who wrote the
original article relating
the displacement of the
talus in the mortise and
the affect of this
displacement on the
ankle joint congruity?
What did this article
conclude?
• Ramsey and Hamilton. JBJS. 1976.
• This article concluded that 1 mm of lateral
displacement of the talus leads to a 42%
reduction in contact area of the ankle joint.
Meaning: reduce your freaking fibular
fracture.However, when doing their
cadaveric experiments, they removed all soft
tissue from around the ankle joint and did
not allow the talus to compensate for being
displaced. More recent studies have
indicated that the talus tends to move back
into the mortise when compressed if
allowed to do so.

34. 11. What are the
radiographic
criteria for
adequate
reduction of
displaced ankle
fractures?
• No widening of the medial clear space
(<4mm) and symmetric joint space on
mortise view - no displacement of malleoli
on AP views
• Less than 2 mm of posterior displacement of
lateral malleolus on lateral films
• No angulations
• Fracture of less than 25 – 30% of the
posterior malleolus

35. 12. The key
points for
fixation are...
• - fibular fracture is the most important
- restoration of fibular length takes
precedent over repair of the inferior tibial-
fibular syndesmosis - realign the ankle
mortise
- evaluation the talar done and tibial plafond
- reapproximation of soft tissue supporting
structures

36. 13. Put the
following in
order
according to
priority
• Blood flow
• Reduction of marked dislocation or
deformity
• Care of open wounds or other soft tissue
injuries
• Precise anatomic reduction of bony
structures
- repair of damaged tendons and nerves
- rehabilitation
- prompt identification and treatment of any
complications that may develop

37. 14. What is
the Cotton
test and
what does it
tell you?
• A way to evaluate the syndesmosis for
rupture or injury
• After fibular fixation, use a large bone hook
to try to laterally distract the fibula from the
tibia while observing the relationship of the
two bones
• If > 3 – 4 mm of lateral sift of the talus
occurs, significant instability is present and a
syndesmotic screw is recommended

38. 15. When
should you
use a
syndesmotic
screw?
• When there is a high fibular fracture or a
positive Cotton test
• More recent studies, however, suggest that
if you have a fibular fracture 5.0 cm from the
ankle joint and distal do not need to be
fixated with a syndesmotic screw
(Kennedy et al. J Orthop Trauma 14(5), 2000)

39. 16. How do
you insert a
syndesmotic
screw?
• From the lateral fibula angulate the screw
about 25% anteriorly and penetrate three
cortices with the foot at 90 degrees to the
leg.
• Olerud (Arch Ortho Trauma Surg 104:299,
1985) demonstrated a 0.1 degree loss of
dorsiflexion for every degree of
plantarflexion that the ankle was in at the
time of fixation of the syndesmosis

40. 17. When is
a
syndesmotic
screw
removed?
• No one agrees on this
• Usually at 6 – 8 weeks post op or
immediately before weight bearing
• It can be left in for longer (12 – 14 weeks) for
increased stability in syndesmotic ruptures
• Or you can use a tightrope for syndesmosis
fixation and you wouldn’t have to remove
that at all

41. 18. Which two
classes of Lauge
Hansen fractures
will most
commonly produce
posterior malleolar
fractures?
• SER and PER

42. 19. What is
the best way
to assess for
a posterior
malleolar
fracture?
• CT or a lateral film (x-ray)

43. 20. When
should a
posterior
malleolar
fracture be
fixated?
• > 25 – 30% of the joint surface is involved
when ORIF is indicated

44. 21. What are
the names of
two approaches
to fixate a
posterior
malleolar
fracture?
• Anterior approach through the same incision
used to fix the medial mall fractures
• Posterolateral approach of Henry (1945).
Incision between the peroneal and Achilles
tendons; avoids damage to the sural nerve
and avoids the NV bundle medially. The FHL
muscle is used as a guide to the fragment

45. 22. What is
the posterior
malleolus?
• A tubercle at the posterior border of the
fibular notch on the lateral surface of the
distal tibia

46. 23. What is a
triplane
fracture and
why does it
occur?
• Pediatric fracture that appears as a SH2 on the
lateral (with the Thurston Holland sign) and a
SH3 on the AP
- Occurs in kids around 14 yrs of age where the
medial aspect of the growth plate is closed and
the lateral side remains open
• Vertical fx of the epiphysis from the joint space
to the physis that is orientated in the sagittal
plane
- This fracture changes directions when it
reaches the physis and orientates itself in the
transverse plane
- It then changes direction again and continues
into the metaphysic in the coronal plane and
exits the bone posteriorly.

47. 24. What
should you
do with a
pediatric
fracture?
• Order a CT to r/o a triplane fracture and to
determine growth plate involvement

48. 25. With which
Saltar-Harris
fracture pattern
in a Juvenile
Tillaux fracture
associated?
• SH 3

49. 26. How does
a Danis-
Weber B
fracture
displace?
• Posterior and superior

50. 27. What is
an antiglide
plate?
• - This plate was developed because of the
difficulty encountered with accurately
reducing and securing the Danis-Weber B
fibular fractures by traditional methods
- This plate is put on the posterior side of the
fibula
- A 5 hole 1/3rd tubular plate is used with
three holes above and two holes below the
fracture
• - An interfragmentary screw can be used
through one of the holes

51. 28. Name
some
disadvantages
of using a
lateral fibular
plate.
• - Frequent plate and screw irritation due to
the superficial nature of this bone
- Closure problems? Also due to superifical
nature of the bone
- Hard to fit the shape of the fibula due to
the torque required
- Possibility for penetration of the distal
screws into the talofibular and tibiofibular
articulations

52. 29. What are
the four
principles of
pilon fracture
reduction?
• - reconstruction of the fibular fracture
- reconstruction of the tibial articular surface
- cancellous graft to fill the distal tibial
metaphyseal defect
- buttress plate application to the medial or
anterior aspect of the tibia

53. 30.
Classifications
for Pilon
fractures
• a. Ruedi and Allgower
• b. Lauge Hansen, PDF
• c. Mueller (AO system)

54. Ruedi and
Allgower
•
Type I: Mild displacement and no
comminution without major disruption of
the ankle
• joint
Type II: Moderate displacement and no
comminution with significant dislocation of
the ankle joint
Type III: “Explosion fracture”; severe
comminution and displacement of the distal
tibial metaphysis; significant displacement
and loss of cancellous bone

55. Lauge
Hansen, PDF
• Stage I – medial malleolar fracture
• Stage II – fracture of the anterior lip of the
tibial plafond
• Stage III – fibular fx above the level of the
syndesmosis
• Stage IV – transverse fracture of the distal
part of the tibia at the same level as the
proximal margin of the large tibial fracture

56. c. Mueller
(AO system)
• Type A – Extra articular
• Type B – Partially articular
• Type C – Completely articular
All of the above can include:
A: no comminution or impaction in the
articular or metaphyseal surface
B: impaction involving the supra-articular
metaphysis
C: comminution and impaction involving the
articular surface with metaphyseal impaction

57. 31. A pt presents to the
ER and you are the
resident on call. X-rays
show a short oblique
fracture of the fibula at
the level of the
syndesmosis. What else
do you want to know
about the x-rays and
what do you tell your
attending on the phone?
• X-rays:
Fibular displacement
Relationship of the talus to the tibia
Medial clear space
Posterior malleolus and syndesmosis
involvement
• Tell your attending that you have bi-
mallelous fracture that needs ORIF

58. 32.
Radiographic
evaluation of
ankle
fractures
should
include:
• Medial clear space
< 4 mm on the mortise views with relatively
symmetric joint space
• Talocrural angle
83 + 4 degrees - or – within 2 degrees of the
contralateral side
• Talar tilt angle - Shenton’s line
• The continuous curve between the lateral
talus and the recessed tip of the distal fibula
- Syndesmotic width
• Less than 5 mm on the AP view

59. 33. You have a 70
y.o. active female
patient who sustains
a Danis-Weber B
type fracture that
needs ORIF. Pt has a
smoking history.
What are you
worried about?
• Quality of her bone – will it hold fixation?
• Healing potential

60. 34. During her surgery,
you attempt to apply a
lateral plate and screws
to fixate the fracture.
After several attempts, it
is deemed that the
fixation will not help in
her soft bone. What do
you do?
• Insert an IM rod (Rush rod) from
anterolateral at the distal end of the fibula
and proceed proximally
• IM fixation is great in elderly patients; they
can weight bear soon with this type of
fixation. Pritchett (Ortho Review June 1993)
showed 88% of pts treated with Rush rods
had a good or fair functional result
compared with 76% treated with the AO
Method. FWB was possible 6 weeks earlier
with Rush rods than with plates and screws.
Study was done on pts over 65 y/o.

61. 35. Muller
classification
of medial
malleolar
ankle
fractures.
• Type A: avulsion of the tip
• Type B: avulsion at the level of the ankle
joint
• Type C: oblique fracture
• Type D: vertical fracture

62. 36. What are
three ways
to fixate the
medial
malleolus?
• Single or double screw fixation
• K-wires
• Tension band wiring technique
• Johnson and Fallat JFAS, 1997, showed that
cancellous screws (two) exhibited only
47.16% of the strength of tension band
wiring at clinical failure.

63. 37. What are
some
complications
of ankle
fractures?
• Delayed or non union NV injury
Post traumatic arthritis Infection
(particularly if open fracture) RSD

64. 39. Using Lauge
Hansen, what is
the most
common ankle
fracture?
• SER

65. 38. Using
Lauge
Hansen what
is the most
common
ankle injury?
• SAD

66. 39. Using
Lauge Hansen,
what is the
most common
ankle
fracture?
• SER

67. Pilon
Fractures
• (As presented by Roy Sanders, MD, 9/21/2000 at Loyola
University) Treatment:
• Plate the fibula
• External fixation; wait 10 – 21 days (edema resolution)
• Fixate the tibia
• Metaphyseal plate (M-plate; Sanders & Bone)
• Spider plate
• Spring plate; spoon plate (6.5 cancellous screws)
• 1/3 tubular plate hammered flat
• Anatomic reduction: a congruous joint is the goal; the only
way to achieve a congruous joint is to ORIF the injury
Recommended text: Planning and Reduction Techniques in
Traumatic Fractures