Dislocated Ankle (Ankle Dislocation)

A dislocated ankle means that the tibia and talus no longer maintain their normal anatomic relationship.

The ankle is a hinge joint that connects the lower leg to the foot. The tibia and fibula of the leg come into contact with the talus of the foot, forming the ankle mortise. The majority of the weight-bearing in the ankle occurs between the tibia and talus. While the shape of the mortise helps align the ankle joint, the surrounding ligaments are very important for providing stability.

A dislocated joint describes the situation where the bones that come together to form a joint no longer maintain that normal relationship. In the ankle, it means that the tibia and talus no longer maintain their normal anatomic relationship.

Most commonly, a dislocated ankle is associated with fractures of the distal ends of the tibia and fibula (called the malleoli) in association with damage to the ligaments that help support the ankle joint. Less commonly, isolated ligament injuries can result in dislocation.

Ankle dislocations do not happen spontaneously but are a result of trauma. Forces placed on the ankle can cause the bones to fracture or the ligaments to tear, resulting in the potential for a dislocation injury.

The ankle is an inherently stable joint and the direction of the dislocation depends upon the position of the foot and where the force arises. Ankle dislocations are more often associated with fractures of the bones that make up the joint.

Common causes of dislocations include:

• falls,
• motor-vehicle crashes, and
• sports injuries.

The most common type of ankle dislocation is the posterior dislocation, where the talus moves backward in relation to the tibia. For this to occur, the foot needs to be plantarflexed (the toes are pointing downward) when the injury occurs and the ankle is either forced inward from the outside (inversion) or outward from the inside (eversion), tearing the ligaments and tissues that hold the ankle stable.

• Anterior dislocations, where the talus is pushed forward, occur when the foot is fixed or dorsiflexed (where the toes are pointed upward). The force from in front of the foot pushes the tibia backward.
• Lateral dislocations occur when the ankle is twisted, either inverted or everted, but there are always fractures associated with either the medial or lateral malleolus or both.
• Superior dislocation describes the situation where the talus is jammed upward, into the space between the tibia and fibula, as a result of an axial loading injury and is called a pilon injury. This may be due to landing on one's feet from a fall or from being in a car wreck where the foot is held firmly against the brake pedal.

• Dislocations are painful, and there is usually obvious deformity of the ankle joint. It may be very difficult or impossible to stand or walk.
• If the nerves that run across the ankle joint are damaged or inflamed, there can be numbness and tingling of the foot.
• There is almost immediate swelling of the ankle joint area, and ecchymosis (bruising) may occur quickly.
• Depending upon the mechanism of injury, there can be associated other injuries to the foot, knee, or spine.

The health care professional needs to take a history as to how the injury occurred. Appreciating the mechanism helps make sense of the injury and may help direct treatment. Past medical history and previous ankle injury may provide useful information.

• The dislocated ankle is often diagnosed clinically by the appearance of the ankle. The physical examination can determine the abnormal relationship of the tibia, fibula, and talus. In addition to the ankle, the health care professional may also examine the structures of the foot and knee, looking for other potential associated injuries.
• Because blood vessels and nerves can become stretched and damaged when the ankle dislocates, pulses and sensation in the foot are evaluated. Skin complications are common because as the skin can lose its blood supply as it is stretched over a bony prominence when the ankle is dislocated.
• X-ray is the initial diagnostic test used to determine the extent of injury, whether a fracture is present, and how the bones are positioned in relationship to each other. Once the dislocation is reduced and the bones realigned, another post-reduction X-ray may be done to confirm that realignment has occurred with the bones located in their normal position.
• Depending upon the situation, CT or MRI scans might be considered to evaluate the damage to the joint surface, look for occult or hidden fractures, and assess the ligaments and tendons that surround and stabilize the ankle joint. Often these tests are done after the dislocation has been treated.

A dislocated ankle is an orthopedic emergency. Once the initial evaluation is complete, the goal of emergency treatment of an ankle dislocation is to reduce the injury, returning the bones as close as possible to their normal anatomic position. Often the bones will fall back into place with gentle traction. Sometimes medication may be required to sedate the patient and help the muscles surrounding the ankle relax.

• If there is evidence that the blood and nerve supply to the foot is in jeopardy or if the skin is tented and stretched and the clinical diagnosis of ankle dislocation is made, attempts to reduce the ankle joint may be necessary even before X-rays are taken.
• Once the ankle joint is reduced, examination of the blood and nerve supply to the foot is repeated and a temporary plaster or fiberglass splint is placed to hold the bones and joint in position
• An orthopedic or podiatric consultation may need to occur emergently, especially if there are unstable fractures present, if nerve or artery damage exists, or if the ankle cannot be reduced and an emergency operation is needed.
• Even if the ankle dislocation is reduced, surgery may be required to stabilize the structures that were damaged. The decision as to whether surgery is required and what type of surgery might be needed is individualized for each patient and their situation.

How long does it take to recover from a dislocated ankle? After the initial treatment is complete, regardless of whether surgery is required, rehabilitation may take 6 to 12 weeks before returning the patient to their pre-injury activities.

Some dislocations may need surgery based on the severity of the trauma. If a patient undergoes surgery, the recovery time may be longer and depends on the surgical procedure. It may take six months to up to a year for the ankle to fully recover from the trauma after the surgery.

During recovery, it is essential to keep the ankle immobilized and avoid weight-bearing on the dislocated ankle. The patient may use assistive devices, such as crutches, walker, or a knee scooter to move around and prevent putting weight on the injured ankle. Once the brace or splint is removed, physical therapy may be necessary to restore range of motion and strengthen the ankle. For athletes, modifying activity and movement patterns is crucial to prevent placing undue stress on the injured ankle during the recovery process.

The goal for every injury is to return the patient to their pre-injury level of function, but patients who have dislocated their ankle may not necessarily be able to achieve that goal.

When the ankle dislocates, the blood supply to the cartilage that lines the surface of the bone within the joint may be damaged, and could lead to arthritis (arthro = joint + itis = inflammation). If the bones do not perfectly align after the injury is reduced, the risk of arthritis in the future increases.

Arthritis of the joint may cause pain and stiffness. Loss of range of motion in the ankle can alter gait, affecting other parts of the skeleton including the hips and back.

A dislocated ankle is an accidental injury and most often cannot be prevented.

The risk factors are few:

• Recurrent sprained ankles that cause the ankle joint to be lax
• Weakness of the muscles that surround and support the ankle, especially the peroneal muscle
• Diseases that cause joints to be hypermobile, for example, Ehlers-Danlos syndrome, Marfan syndrome, and Down syndrome.

• What are the symptoms of a dislocated ankle? A dislocated ankle causes symptoms like pain, swelling, bruising (ecchymosis), numbness, and tingling in the foot. The ankle joint is unable to move and there is inability to bear weight.
• How is a dislocated ankle treated? Initial treatment for a dislocated ankle begins with reducing the ankle joint and returning the bones to their normal position and relationship with each other. This may include gentle traction to realign the bones, then protecting the joint as it heals in a splint or cast, and then physical therapy to return range of motion and function to the ankle joint. Some ankle dislocations require surgery to repair the injury and to stabilize the bones to prevent them from shifting out of place.
• Can you walk on a dislocated ankle? No, the pain and deformity of a dislocated ankle make it almost impossible to weight bear or walk
• What causes an ankle to dislocate? Ankle dislocation typically occurs due to severe trauma, such as a car accident, fall, or injuries during high-intensity sports.
• Is surgery required for a dislocated ankle? Surgery may be required, especially if the dislocation causes a bone fracture, and the ankle joint cannot be kept in alignment.
• What is the difference between a dislocated ankle and a sprain? A sprain describes an injury to the ligaments that stabilize joints, while a dislocation occurs when the bones become misaligned at the joint. While all joint dislocation has ligament damage and by definition an associated sprain, most sprains do not result in a dislocated ankle
• Can a dislocated ankle heal on its own? No, a dislocated ankle cannot heal on its own. It requires medical intervention to properly realign the bones and restore the joint to its normal position.
• What should you do immediately after dislocating your ankle? If you suspect an ankle dislocation, seek medical help immediately. While waiting for help, you can apply ice to the injured joint for 10-20 minutes. Do not attempt to move the joint or try to realign it yourself. Elevating the ankle above the level of the heart will help decrease swelling.
• How can you prevent an ankle dislocation? Ankle dislocations are usually caused by accidents or falls, which are difficult to prevent. However, you can take precautions to reduce the risk of injury, such as maintaining a healthy lifestyle, wearing proper footwear, and avoiding situations that may lead to falls or trauma.