Fractures of the Ankle
Fractures of the ankle range from relatively minor twisting injuries to those that are associated with violent disruption of the ankle. There are two different mechanisms of injury which have different effects on the structure of the ankle. The first one is where there is a twisting mechanism and the body rotates around the foot. The other is where there is a crushing type mechanism that impacts the foot. The twisting type of injuries are far more common, and although there is less likelihood of damage to the cartilage, the bones that make up the ankle joint must nonetheless be carefully re-aligned. The second type of injury which occurs from a fall from a height, or in a motor vehicle accident is usually far more serious and is often associated with cartilage damage.
The ankle consists of the inner aspect of the tibia (the medial malleolus), the outer aspect of the ankle (the fibula), and the bone underneath the ankle (the talus). There are many different varieties and grades of severity of ankle fractures. These may involve only the medial malleolus, only the fibula, or both bones (which is called a bi-malleolar fracture). At times the talus may completely pop out of the ankle joint associated with the fracture. We call this a fracture dislocation.
If you think about the way that the ankle works, even the slightest abnormality of the bone structure may lead to problems.
If the shape and anatomy of the ankle are not accurately restored, the cartilage lining of the ankle will be disturbed. This will inevitably lead to arthritis. Think of arthritis as a wearing away of the grisel lining of the bone. Imagine the end of a chicken bone which is lined with cartilage. Every joint in the body is lined with cartilage, and loss of the cartilage leads to the development of arthritis. Therefore, the goal of treating all ankle fractures is to re-position the bones to prevent the occurrence of arthritis. Some minor ankle fractures can be treated in a boot or a cast without surgery. The majority of ankle fractures, however, do require operative treatment. Surgery is performed with incision(s) on one or both sides of the ankle. Screws and/or a metal plate are inserted into the medial malleolus and the fibula in order to accurately restore or reduce the fracture alignment.
Following surgery, a bandage with plaster is applied to the ankle. The bandage remains until the stitches are removed (usually about two weeks). At that time exercise activities are initiated. No walking on the ankle is permitted for approximately six weeks. At that time protective walking (with a removable boot or brace) may be allowed. Physical therapy exercises, swimming and biking are important parts of the recovery process. They strengthen the leg and develop movement of the ankle.
If the ankle is not repaired correctly or does not heal well, arthritis and deformity of the ankle can occur. Some of these patients will have no other option but to have the ankle surgery re-done. Dr Myerson has developed techniques for salvaging very severe deformities of the ankle after unsuccessful fracture treatment.
 |
 |
The image on the left is that
of a fractured ankle which had been treated with attempted
screw and plate fixation. This did not heal correctly,
and the ankle became deformed and if left untreated, will
develop severe arthritis. This was corrected with a complete
reconstruction of the ankle restoring the alignment. |
|
|
The ankle joint is a unique structure which depends on perfect alignment
of the bones for normal function. Although the ankle moves in an
up and down direction (called dorsiflexion and plantarflexion), there
is very subtle movement with twisting, called rotation. In order
for the ankle to work efficiently, the bones need to line up perfectly
in the socket, which we call the mortise. If you look at the pictures
below, it is easy to see the difference between a perfect ankle anatomy,
and one which is very deformed following a fracture.
| |
|
|
|
On the left is a picture of a normal
ankle XR. The shadow in the middle of the ankle joint
is the cartilage space, which does not show up on an
XR. Note on the middle XR the changes in the position
of the ankle after a fracture which was inadequately
fixed with a plate and screws. This is a serious problem
and is associated with terrible deformity. This was well
reconstructed by re-breaking the ankle, and fixing it
again with a plate and screws as can be seen on the right
hand XR. |
|
| |
|
|
| |
|
|
| |
|
|
| |
On the left again is the normal XR
of the ankle. It is easy to see the overlapping shadow
on the outside of the ankle which indicates the normal
bone structure. The overlap is highlighted in the circle. |
|
| |
| |
|
|
| |
On the left hand XR you can see again
the space between the talus and the fibula which is abnormal.
This occurred after a fracture of the fibula (called
a high fibula fracture, and which cannot be seen on this
XR). If the ankle is left in this position with the fibula
shifted outward, arthritis of the ankle will inevitably
occur. In order to correct this, the fibula had to be
broken again and then fixed with a plate and screws.
You can see that the space between the talus and the
fibula has now been corrected. |
|
| |
|
|
| |
 |
|
| |
|
|
| |
There are times when the deformity
which occurs after an ankle fracture can be subtle, but
still cause severe problems leading to arthritis. It
has been demonstrated scientifically that even very slight
shifts of the ankle of 2mm can lead to the development
of arthritis. In the XR on the left, the fibula was fractured,
but not treated with surgery. This is a difficult problem,
since the ankle no longer lines up correctly, and was
treated by making a large cut in the tibia bone, and
removing a wedge of bone from the tibia to line it up
correctly. This can be seen on the red lines which should
be exactly perpendicular to each other as on the right
hand XR following the corrective surgery. |
|
| |
|
|
| |
 |
|
| |
|
|
| |
There are times when the deformity
is really severe as in this patient with rheumatoid arthritis.
This patient suffered from a stress fracture of the fibula,
and the ankle then collapsed, and the foot became severely
flat. This had to be reconstructed by cutting both the
tibia and the fibula (called an osteotomy) and then by
inserting a large specialized bone graft in both the
tibia and the fibula to re-position the ankle correctly. |
|
|
|
|
