Topics
Lauge-Hansen Classification
Danis-Weber Classification
Berndt-Hardy Classification
Salter-Harris Classification
Reudi and Allgower Classification |
Supination-Adduction
Supination-External Rotation (SER)
Pronation-Abduction
Pronation-External Rotation (PER)
Pronation-Dorsiflexion
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Tillaux-Chaput fracture
Le Fort-Wagstaffe fracture
Maisonneuve fracture
Volkmann's fracture
Pilon fracture
Thurston-Holland Sign |
For information about ankle sprains--injury to the soft tissues surrounding the ankle joint, visit our web
page by clicking on the X-ray of the ankle below:
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There are several systems to classify
fractures of the ankle. We'll review 3 of the most common classification
systems, each of which classifies different sorts of injuries.
The Lauge-Hansen Classification is the
classic way to describe typical ankle fractures. It's an interesting
system because it attempts to describe the mechanism of the injury, by
classifying the foot in terms of both the position of the foot and the motion
that occurred to create the fracture. This system predicts locations of
soft tissue and bony injuries that may not be easily seen on X-ray, and it
allows the user to reverse the mechanism to reduce (correct) the fracture.
There are five types of Lauge-Hansen
fractures: Supination-Adduction, Pronation-Abduction, Supination-External
Rotation, Pronation-External Rotation, Pronation-Dorsiflexion, each with
progressive stages of injury. The first name of the Lauge-Hansen
fracture is the position of the foot when the fracture occurs. The second
name is the direction of movement responsible for the fracture.
STAGE I: Involves either a lateral
ligament injury, or a transverse avulsion (pull-off) fracture of the
lateral malleolus below or at the level of the ankle mortise. (*****The
transverse fracture of the lateral malleolus is the classic,
hallmark finding of the Supination-Adduction injury.)
STAGE II: Is characterized by a stage I injury coupled with an
oblique fracture of the medial malleolus.
Supination-Adduction injuries generally heal
favourably.
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STAGE I: Involves a
fracture of the medial malleolus or a tear in the medial malleolus' deltoid
ligament.
STAGE II: Stage I, plus a rupture of the anerioinferior tibiofibular
ligament (the ligament on the front of the ankle, holding the tibia and fibula
together), or a small pull-off (avulsion fracture of the anterior (front)
portion of the tibia (which is known as a Tillaux-Chaput fracture), or fibula
(which is known as a Le Fort-Wagstaffe fracture).
STAGE III: Stage II, plus an oblique (angled) fracture of the fibula above the
malleolus.
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Supination-External Rotation
(SER) This is the most common mechanism
of ankle fracture. It begins at the front of the ankle, then
rotates around the ankle next affecting the outside of the ankle, then the
back, then the inside.
STAGE I: Involves either a rupture of the anteroinferior
tibiofibular ligament (the ligament on the front of the ankle, holding
the tibia and fibula together), or small pull-off (avulsion) fracture of
the anterior (front) portion of the tibia (which is known as a
Tillaux-Chaput fracture), or fibula (which is known as a
Le Fort-Wagstaffe
fracture).
STAGE II: Stage I plus a spiral oblique fracture of the lateral
malleolus. (****This spiral fracture
at
the level of the lateral malleolus is the classic, hallmark finding of
the Supination-External Rotation fracture.)
A good example of this fracture is seen to the right.
While both SER and PER injuries demonstrate spiral
fractures, note that this fracture is well below the
fracture seen in the PER example below.)
STAGE III: Stage II plus a fracture of the posterior portion of
the tibia (Volkmann's fracture).
STAGE IV: Stage III plus a fracture of the medial malleolus.
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Pronation-External Rotation
(PER) As with the SER
fracture, the PER also rotates around the ankle, only this injury begins on
the inside of the ankle, then moves to the front, then the outside, then the
back of the ankle.
STAGE I: A short, transverse fracture of the medial malleolus or a
tear of the deltoid ligament (demonstrated well by the picture one the
right.)
STAGE II: Stage I plus a tear of the anteroinferior tibiofibular
ligament (the ligament on the front of the ankle holding the tibia and
fibula together), or a small pull-off (avulsion fracture of the anterior
(front) portion of the tibia (which is known as a Tillaux-Chaput
fracture), or fibula (which is known as a Le Fort- Wagstaffe
fracture).
STAGE III: Stage II plus a tear in the interosseous membrane (the
ligament-like sheet holding the tibia and fibula together) and a spiral
fracture of the fibula above the lateral malleolus. (****This
spiral fracture of the fibula well above the lateral malleolus is
also known as a Maisonneuve fracture, and is the classic, hallmark
finding of the Pronation-External Rotation fracture.)
This fracture is demonstrated well on the picture to the right.
STAGE IV: Stage III plus a fracture of the posterior tibia
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STAGE I: Involves a fracture of the medial malleolus
STAGE
II: Stage I plus a fracture on the anterior-inferior portion of the tibia.
STAGE
III: Stage II plus a transverse fracture of the fibula above the
malleolus. STAGE
IV: Stage III plus a fracture of the distal tibia (Pilon fracture).
Reudi
and Allgower subdivided these into Grade I
(involving a "cleavage" fracture of the distal tibia with no
disruption of the internal surface), Grade II (involving internal surface
disruption, but no comminution (fragmentation into multiple pieces), and Grade
III (involving impaction and comminution).
Danis-Weber Classification System
Another way to describe ankle injuries
is the Danis-Weber Classification System. Less complicated than
Lauge-Hansen, Danis-Weber simply describes the location of the injury in
relationship to the syndesmosis (the ligament-like sheath between the leg bones
(the tibia and fibula)).
TYPE A:
Occurs beneath the level of the syndesmosis. Corresponds to the Lauge
Hansen "Supination-Adduction" fracture, and so, is also associated
with a vertical fracture of the medial malleolus.
TYPE B:
Occurs at the level of the syndesmosis. Corresponds either to the Lauge-Hansen
"Supination-External Rotation" or "Pronation-Abduction"
fractures. The posterior portion of the tibia might also be fractured.
TYPE C:
Occurs above the level of the syndesmosis. Corresponds to the Lauge
Hansen "Pronation-External Rotation" fracture. Associated with
an avulsion fracture of the tibia, deltoid ligament rupture and fractures of the
posterior malleolus.
Berndt-Hardy
Classification System
The Berndt-Hardy Classification System
only describes fractures of the talar dome--the surface of the ankle bone as it
fits in between the leg bones.
Talar dome fractures typically strike
either the the anterior-lateral (front and outside) portion of the bone (44% of
cases) or the posterior-medial (back and inside) portion of the bone (56% of
cases). Anterior-lateral injuries are associated with
inversion
and dorsiflexion motion, and posterior-medial injuries are associated with
eversion
and plantarflexion motion.
STAGE ONE:
A small area of compression of the subchondral bone (the bone beneath the joint
surface). This usually has no symptoms and is often simply diagnosed as an
ankle sprain. Treated conservatively with rest, ice, compression,
elevation and often, a non-weight-bearing, below-the-knee cast for 6
weeks. Some degree of bracing of the foot and leg after the cast is
removed may be necessary.
STAGE TWO:
The
subchondral bone becomes partially detached. This condition is painful and
associated with ankle ligament injury. Some loss of ankle joint stability
is common. Treatment is usually as with stage 1 injuries.
STAGE THREE: The subchondral bone fragment is
completely detached, but still in the same position. Pain is usually
relatively severe. There may be limitation of ankle motion or a feeling of
creaking within the ankle joint. Often associated with a loss of joint
stability. May respond to conservative treatment or require
surgery.
STAGE FOUR:
The subchondral bone
fragment is detached and displaced from its normal position. Pain is
usually severe. Often accompanied by limitation of ankle motion, and a
creaking or gritty feeling within the ankle with motion. Often
associated with a loss of joint stability. Treatment is usually surgical,
involving removal of the fragment, and when possible, repositioning the
fragment, using
fixation.
Salter-Harris Classification System
The Salter Harris Classification
System describes only injuries that occur around growth plates.
Hence, only children can get Salter-Harris fractures.
Salter-Harris injuries frequently affect the
ankle, but really, this sort of injury may affect any bone with a growth
plate.
To see what a growth plate looks like, take
a look at the example to the right. This is a picture of the
proximal phalanx of the great toe--the first bone in the big toe.
The line running across the bone (transversely) is the growth
plate. Because it is composed of growing cartilage and not bone,
it looks invisible on X-ray.
Below you can see growth plates in both the
leg bones, the tibia and fibula. |
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Salter Harris fractures are generally broken down into five categories:
Type I
injuries can be thought of as a fracture through the growth plate.
They involve a separation of the two portions of bone, with the growth
plate being the area of weakest link, and the area of fracture.
There are frequently no changes seen on X-ray, though the growth plate
may look wider than on the other limb.
These injuries are generally immobilized to
allow the tissues to heal. Prognosis
is excellent. |
Type II
injuries
(the most common type) involve a fracture through the growth plate, but instead
of running all the way across the growth plate, a portion of the fracture
extends back into the shaft of the bone. That fragment of bone is known as
the "Thurston-Holland" sign. Prognosis is still excellent. Type
III injuries also involve a fracture extending partially through the growth
plate, only this time the fracture extends not towards the shaft of the bone,
but out towards the joint.
Type III
injuries
also consist of a fracture part way across the growth plate, only this time
instead of extending into the shaft of the bone, the fracture extends out
towards the joint. Because these injuries may affect the joint, the
prognosis is more guarded than with Types I and II, but it is still generally
good.
Type IV
injuries
extend across the growth plate--from the shaft of the bone, across the growth
plate, and into the joint. Premature arrest (stoppage) of normal growth is
common, and surgical repair is usually needed to restore proper anatomical
alignment.
Type V
injuries involve a compression of the growth plate. As with Type I, X-rays
are generally useless in diagnosing this problem. Prognosis is variable,
with premature arrest (stoppage) of normal growth being the biggest risk.
Peterson added a
Type
VI category, which is characterized by a portion of
the bones surrounding the growth plate and the growth plate itself is
missing. This is most commonly seen in such traumatic insults as a
lawnmower injury.
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