Ankle fractures

Ankle fractures are one of the more common injuries that an orthopedic surgeon treats.

The severity of these injuries ranges from the milder nondisplaced isolated lateral malleolar fractures, to the more severe bimalleolar fracture dislocations. The word "trimalleolar" is also used sometimes when the posterior injury is visible on xrays.

The ankle is the meeting place of 3 bones:

  1. Tibia
  2. Fibula
  3. Talus

The tibia takes roughly 80% of the load, the fibula takes 20% of the load of your body as you walk or stand on your ankle.

The most common type of ankle fracture occurs as a typical progression of injuries:

  1. The anterolateral ligaments are first torn. If the injury stops here, it is called an "ankle sprain."
  2. If the injuring force continues to be applied, the lateral malleolus is fractured next. At this point the ankle still is stable though.
  3. The posterior ligaments, posterior malleolus, or the syndesmosis ruptures next. After this occurs, the ankle becomes unstable. At this stage, surgery offers the best chance for healing of the ankle in appropriate alignment and for walking comfortably. Casting alone, without anatomic internal fixation, will predictably result in an unstable, painful, arthritic ankle.
  4. Next the medial malleolus is fractured. After this happens, the ankle can dislocate with minimal force. If the joint dislocation is reduced, the weight of the foot itself can be sufficient to redislocate the joint.

The purpose of surgical treatment is restoration of normal alignment of the broken bones. This is done with a combination of screws and plates. These devices however are not strong enough to allow immediate weight bearing. After surgical treatment of unstable ankle fractures, weight bearing is not advisable for a minimum of 6-8 weeks.

An open, trimalleolar fracture dislocation

As an illustration, the following describes a severe, limb threatening, ankle fracture.

This was a 42 year old male who fell from a roof. He was brought to hospital by ambulance (911) with a grotesquely deformed, bleeding ankle.

As is most appropriate, the ER physician reduced the ankle immediately upon seeing the patient, and ordered antibiotics.

Here are initial xrays.

Standard care for these injuries is emergent surgery. Traditional orthopedic dogma dictates irrigation, removal of all debris and devitalized tissue within 6 hours. This is being challenged by some orthopedic traumatologists, but it still remains the standard.

The patient was taken to the operating room on emergency basis.

Here is a picture of the ankle as it is being washed and prepped for surgery.

After thorough cleaning, sterile drapes are applied. The ankle is redislocated, the bone ends are delivered, inspected under direct vision, cleaned, irrigated. All gross foreign debris must be removed. Devitalized tissue must be removed. Sometimes it is not easy to tell whether a fragment of tissue is devitalized or not. A lot of judgement goes into this. Oftentimes the wound is reexamined and redebrided at repeat surgery.

Here is a view of the cleaned out ankle, a look at the articular cartilage of the distal tibia plafond.

After cleaning the wound and the broken bone ends, the surgeon has a choice: proceed with definitive treatment with plate and screws, or apply temporary stabilization, an external fixator.

The worse the soft tissue and skin injury, the more likely the application of an external fixator, for several reasons:

  1. Open wounds often need to be reexamined and cleaned at a second, a third, or a fourth surgery.... Definitive surgery can be fouled up by infection of an open wound. It makes sense to delay definitive treatment until one is sure that the open wound will heal.
  2. An external fixator does not require large incisions, it truly is minimally invasive. It allows easy monitoring of wounds, it can be easily adjusted if needed.
  3. Operating room logistics dictate that initial emergent surgery be quick, so as not to interfere with the other planned surgeries of the day, the workflow of the rest of the hospital, etc. An external fixator can be placed much more quickly than the definitive plates and screws.

An external fixator was placed in this patient as well. Metal pins were drilled in the tibia shaft, a single metal pin was drilled through the calcanus (heelbone), and these were connected with two carbon fiber rods. The carbon fiber rods are marked with the green arrows in the picture below.

Internal fixation of the medial malleolus was performed in the initial operation because the fracture was already exposed, and the medial wound potentially could be closed once and for all after the first surgery.

The definitive surgery was performed 2 days later. This second surgery consisted in opening, reduction, and fixation of the fibula. The fibula was fixed with a long plate, and a syndesmosis screw was placed as well.

Rehabilitation progressed slowly.

The initial splint placed during surgery was removed at 2 weeks. Sutures were removed at that time as well. Wounds healed well.

A cast was applied for another 6 weeks.

After the cast was removed, the patient was given a CAM walker, one of those braces that look like ski boots. He wore that for another month full time, and weaned himself in the 4th month.

After the first two months after surgery, the patient was allowed to gradually bear weight, initially at 25%, and going up by 25% every month.

By 6 months the xrays looked good, the patient was pain free, walking without a limp.

The following xrays were done 7 months after the injury. The patient had elected to not remove the syndesmotic screw, to allow the screw to break.

Here is the appearance of the ankle. The horrendous open wound has healed well.