Ankle Joint Fracture – Causes, Symptoms, Treatment

Ankle Joint Fracture/An ankle fracture is a break of one or more ankle bones. Symptoms may include pain, swelling, bruising, and an inability to walk on the leg. Complications may include an associated high ankle sprain, compartment syndrome, decreased range of motion, and malunion.^[rx][rx]

Fractures of the ankle joint are among the commonest fractures in adults, with an incidence of up to 174 cases per 100 000 persons per year [rx]. For a good long-term functional outcome to be achieved, reliable early evaluation is crucial so that it can be determined whether the problem is a distortion (sprain), ligament rupture, bony ligament avulsion, or fracture of the talocrural joint. The proper treatment is chosen on the basis of the mechanism of the accident and the correct classification of the injury and accompanying soft-tissue damage. The goal of treatment is to enable the patient to put his or her full weight on the joint once again without pain and to prevent permanent damage.

The ankle joint is a highly complex joint. The ankle joint has multidirectional mobility for its complex role in supporting the weight of the body and fulfilling a myriad of daily functions. It is a combination of bones and ligaments structured around the talus. It includes the tibia, fibula, calcaneus, the tibiofibular ligament, the lateral ligament complex, and the medial ligament complex. The talocrural joint is the place where the distal tibia, distal fibula, and talus articulate. The tibia and fibula are anchored together via the syndesmosis. The syndesmosis consists of the interosseous membrane as well as the transverse, anterior, and posterior tibiofibular ligaments. There are both lateral and medial collateral ligament complexes which help to increase the stability of the ankle joint. The lateral collateral ligament forms from the fibulocalcanear ligament (FCL), the anterior fibulotalar ligament (AFTL), and the posterior fibulotalar ligament (PFTL). The medial collateral ligament consists of the deltoid ligament and the plantar calcaneonavicular ligament. The ankle joint moves in a unique way due to its structure. As the talus is asymmetric, the ankle is not purely a hinge joint. Instead, it acts as a rotary hinging movement. As many structures are involved in the ankle joint, in the context of an acute ankle fracture, it is easiest to think of it as a ring of structures situated around the talus. One break in the ring leads to a stable injury, while two or more breaks in the ring lead to an unstable injury.[rx][rx]

Relevant Anatomy of Ankle Joint Fracture

The talocrural joint is the junction of three bony structures: the distal ends of the tibia and fibula and the trochlea of the talus. The tibia and fibula are elastically bound in the fork of the ankle joint by the ligamentous structures of the syndesmosis (interosseous membrane; anterior, posterior, and transverse tibiofibular ligaments) [rx, rx]. Powerful collateral ligaments stabilize the joint against stress from the sides: laterally, the anterior tibiotalar ligament (AFTL), fibulocalcanear ligament (FCL), and posterior tibiotalar ligament (PFTL), and, medially, the broad fan of the deltoid ligament and the plantar calcaneonavicular ligament (spring ligament), whose medial border is blended with the forepart of the deltoid ligament. Because the talus is asymmetrically shaped, movement in the ankle joint is not a pure hinge movement, but rather a rotatory hinging movement around the helical axis of the joint [rx]. Precise congruence of the ankle joint is essential for its proper function, and thus malpositions of traumatic origin have major adverse effects, as they alter the biomechanics of the joint and cause pathological compressive stress [rx, rx].

Ankle fractures are generally to be regarded as joint fractures even if there is no fracture cleft in any of the articular surfaces of the joint. For the ankle joint in particular, non-anatomical reductions and restraints lead to premature degeneration of the joint. Thus, proper anatomical reconstruction—generally involving surgery—is needed to prevent post-traumatic degeneration over the long term.

Pathophysiology of Broken Ankle

There are various methods to classify ankle fractures.

Percival Pott described ankle fractures in terms of the number of malleoli involved (unimalleolar, bimalleolar, and trimalleolar).

The Danis-Weber classification system categorizes ankle fractures by assessing the location of the distal fibula fracture in its relation to the syndesmosis.

• A – Below syndesmosis
• B – At the syndesmosis level
• C – Above syndesmosis (i.e., Maisonneuve fracture)

Although this method describes the fracture relative to the syndesmosis, it does not accurately predict damage or injury to the syndesmosis. It also does not address damage to any medial ankle structure.

Type A is managed operatively with a closed repair. Type B & C require internal fixation.

The Lauge-Hansen classification system uses the mechanism of injury to determine the extent of injury to the ankle joint. By knowing the mechanism of injury or the deforming force, one can establish a sequence of injuries of the likely structures injured. Assessing the mechanism of injury can be valuable in deciding the appropriate treatment.

Supination-Adduction (SA)

• Distal fibula transverse fracture
• Medial malleolus vertical fracture

Supination-External Rotation (SER) – most common ankle injury (60% fractures)

• Anterior inferior tibiofibular ligament injury
• Spiral (or oblique) fracture of the distal fibula
• Posterior inferior tibiofibular ligament injury OR posterior malleolus avulsion
• Fracture of medial malleolus OR deltoid ligament injury

Pronation-External Rotation (PER)

• Fracture of medial malleolus OR deltoid ligament injury
• Anterior inferior tibiofibular ligament injury
• Spiral (or oblique) fracture of the fibula (aspect proximal to tibial plafond)
• Posterior inferior tibiofibular ligament injury OR posterior malleolus avulsion

Pronation-Abduction (PA)

• Fracture of medial malleolus OR deltoid ligament injury
• Anterior inferior tibiofibular ligament injury
• Comminuted or transverse fibular fracture (proximal to tibial plafond)

1st word (position of the foot during the time of injury)

• Pronation:  Eversion, abduction, dorsiflexion; medial ligaments stretched and prone to injury
• Supination: Inversion, adduction, plantarflexion; lateral ligaments stretched and prone to injury

2nd word (movement of talus in ankle mortise relative to the tibia)   Injuries always occur in a cumulative pattern; for example, a SER4 injury includes injuries of SER1, SER2, and SER3.

Pronation-dorsiflexion injuries are not classified in either the Danis-Weber or the Lauge-Hansen systems. Although uncommon, it is a unique mechanism in which injury results from axial loading. An example of this type of injury is a pilon fracture. In this type of injury, the sequence of events is as follows:

• Axial loading drives the talus into the tibia causing a medial malleolus fracture
• Another fracture occurs at the anterior tibial margin
• Supramalleolar fibular fracture
• Transverse fracture of the posterior tibia

Talar fractures often result from sudden hyperextension. Most often they are avulsion fractures on the anterior aspect of the talar neck. CT is the imaging of choice for these fractures. Talar fractures can also be due to pronation injury, plantar hyperflexion injury, or dorsiflexion injury.[rx][rx][rx]

Classification

There are several classification schemes for ankle fractures:

• The Lauge-Hansen classification categorizes fractures – based on the mechanism of the injury as it relates to the position of the foot and the deforming force (most common type is supination-external rotation)
• The Danis-Weber classification categorizes ankle fractures – by the level of the fracture of the distal fibula (type A = below the syndesmotic ligament, type B = at its level, type C = above the ligament), with use in assessing injury to the syndesmosis and the interosseous membrane
• The Herscovici classification categorizes medial malleolus fractures –  of the distal tibia based on level.
• The Ruedi-Allgower classification categorizes pilon – fractures of the distal tibia.

Fracture types

• Pilon fracture (Plafond fracture) –a fracture of the distal part of the tibia, involving its articular surface at the ankle joint.
• Wagstaffe-Le Fort avulsion fracture¨ –  a vertical fracture of the anteromedial part of the distal fibula with avulsion of the anterior tibiofibular ligament.
• Tillaux fracture, a Salter-Harris type III fracture – through the anterolateral aspect of the distal tibial epiphysis.^[rx]

Most common ankle fractures

• Lateral malleolus fracture – This is the most common type of ankle fracture. It is a break of the lateral malleolus, the knobby bump on the outside of the ankle (in the lower portion of the fibula).
• Bimalleolar ankle fracture – This second-most common type involves breaks of both the lateral malleolus and of the medial malleolus, the knobby bump on the inside of the ankle (in the lower portion of the tibia).
• Trimalleolar ankle fracture – This type involves breaks in three sides of the ankle: the medial malleolus of the tibia, as well as the lateral malleolus and posterior malleolus (in the lower portion of the fibula).
• Pilon fracture (also called a plafond fracture) – This is a fracture through the weight-bearing “roof” of the ankle (the central portion of the lower tibia). This is usually a higher energy traumatic injury resulting from a fall from a height.

As the number of fracture lines increase, so does the risk of long-term joint damage. Trimalleolar ankle fractures and pilon fractures have the most cartilage injury and, therefore, have a higher risk of arthritis in the future.

Causes of Ankle Joint Fracture

Ankle fractures can be caused by excessive strain to the ankle joint as well as by blunt trauma.[rx]

• Trips and falls – Losing your balance may lead to trips and falls, which can place excessive weight on your ankle. This might happen if you walk on an uneven surface, wear ill-fitting shoes, or walk around without proper lighting.
• Heavy impact – The force of a jump or fall can result in a broken ankle. It can happen even if you jump from a low height.
• Missteps – You can break your ankle if you put your foot down awkwardly. Your ankle might twist or roll to the side as you put weight on it.
  Sports – High-impact sports involve intense movements that place stress on the joints, including the ankle. Examples of high-impact sports include soccer, football, and basketball.
• Car collisions – The sudden, heavy impact of a car accident can cause broken ankles. Often, these injuries need surgical repair. The crushing injuries common in car accidents may cause breaks that require surgical repair.
• Falls – Tripping, and falling can break bones in your ankles, as can landing on your feet after jumping down from just a slight height.
• Missteps – Sometimes just putting your foot down wrong can result in a twisting injury that can cause a broken bone.

Symptoms of Ankle Joint Fracture

Symptoms of an ankle fracture can be similar to those of ankle sprains (pain), though typically they are often more severe by comparison. It is exceedingly rare for the ankle joint to dislocate in the presence of ligamentous injury alone. However, in the setting of an ankle fracture, the talus can become unstable and subluxate or dislocate. Patients may notice ecchymosis (“black and blue” coloration from bleeding under the skin), or there may be an abnormal position, alignment, gross instability, or lack of normal motion secondary to pain.

• Pain, swelling, tenderness and bruising at your ankle joint
• Inability to move your ankle through its normal range of motion
• Inability to bear weight on your injured ankle — However, if you can bear weight on the ankle, don’t assume there is no fracture.
• In some cases, a “crack” or “snap” in the ankle at the time of injury
• In open fractures, severe ankle deformity, with portions of the fractured bone visible through broken skin
• Pain at the site of the fracture, which in some cases can extend from the foot to the knee.
• Significant swelling, which may occur along the length of the leg or may be more localized.
• Blisters may occur over the fracture site. These should be promptly treated by a foot and ankle surgeon.
• Bruising that develops soon after the injury.
• Inability to walk; however, it is possible to walk with less severe breaks, so never rely on walking as a test of whether or not a bone has been fractured.
• Change in the appearance of the ankle—it will look different from the other ankle.
• Bone protruding through the skin—a sign that immediate care is needed. Fractures that pierce the skin require immediate attention because they can lead to severe infection and prolonged recovery.

Diagnosis of Ankle Joint Fracture

History and Physical

• History is an integral part of any medical evaluation. In addition to the standard history (setting, chronology, location, quality, quantity, aggravating/alleviating factors, associated symptoms), it is important to ask specific questions targeted toward an ankle injury.

Questions include

• Where is the pain? Is this an isolated injury or are there other injuries? Other injuries can be missed if there is a severely distracting injury such as an open ankle fracture-dislocation. Ankle fractures are usually the result of a twisting mechanism sustained as a result of a low-energy injury. A higher energy mechanism should raise the specter of compartment syndrome of the leg or a more grave injury such as a pilon fracture (axial loading). An ambulating patient is unlikely to have an unstable fracture.
• The ankle position at the time of injury and subsequent direction of force generally dictates the fracture pattern, as described by the Lauge-Hansen classification system. Past medical history can also be an important factor. Prior injuries/surgeries to the affected joint may affect the presentation. Comorbidities including diabetes, peripheral vascular disease, and smoking can complicate wound and fracture healing or increase the risk of a Charcot neuroarthropathy. A patient’s baseline/goals should be established through a social history including the patient’s level of mobility pre-injury, home situation, and regular activities as well as their future functional goals.

Physical Examination

• Always examines the contralateral un-injured ankle first, as it helps to establish a baseline ankle examination (what it looked like before injury). It is also vital to examine the tibia, fibula, knee, and foot as well. Some injury mechanisms can cause other injuries superior to the ankle (i.e., Maisonneuve fracture). Examine the ankle visually for swelling, pain, ecchymosis, and soft tissue injury, including abrasions and lacerations.  Palpate the ankle to localize the point of injury. To ensure full examination, work methodically. Starting at the proximal tibia/fibula and working down. Once palpation is complete, perform examinations to assess neurological and vascular integrity.  Assess for sensation, motor function, capillary refill, and pulses. It is important to test the passive and active range of motion, as well as weight-bearing status. It is imperative to assess and continue to monitor for signs of compartment syndrome.[rx][rx][rx]

Evaluation

Ottawa Ankle Rules

Ankle radiographs should only be needed if there is pain or tenderness in either malleolus AND one of the following

• Tenderness of the bone at the posterior edge or tip (within 6 cm) of either the lateral or medial malleolus
• Patient unable to bear weight at the time of injury AND on arrival to the emergency department. Weight-bearing is determined by the patient’s ability to take four steps.

It is important to recall that this set of rules was developed to reduce the number of unnecessary radiographs ordered.  The reported sensitivity of the Ottawa ankle rules are close to 100%, but the specificity is highly variable across all studies; this is believed to be caused by user interpretation of the rules and provider dependent techniques in assessing tenderness on exam. Therefore, although effective, even the correct application of this rule does not 100% rule out an ankle fracture.

Radiological Features

Ankle x-ray: 3 view

• AP view – assess for soft tissue swelling that may lead to the discovery of other more subtle fractures
• Mortise view – taken with the foot in 15 degrees of internal rotation, evaluates talus positioning and syndesmosis widening
• Lateral view – assess for anterior and/or posterior avulsion fractures assess for an effusion of ankle joint

If proximal leg tenderness is present or medial clear space widening with no obvious fibular fracture, radiographs of the tibia and fibula should be obtained to rule out the presence of a Maisonneuve injury. A Maisonneuve fracture is a proximal fibula spiral fracture with concomitant disruption of the distal fibular syndesmosis and interosseous membrane.

If your doctor suspects an ankle fracture, he or she will order additional tests to provide more information about your injury.

• X-rays – X-rays are the most common and widely available diagnostic imaging technique. X-rays can show if the bone is broken and whether there is displacement (the gap between broken bones). They can also show how many pieces of broken bone there are. X-rays may be taken of the leg, ankle, and foot to make sure nothing else is injured.
• Stress test – Depending on the type of ankle fracture, the doctor may put pressure on the ankle and take a special x-ray, called a stress test. This x-ray is done to see if certain ankle fractures require surgery.
• Computed tomography (CT) scan – This type of scan can create a cross-section image of the ankle and is sometimes done to further evaluate the ankle injury. It is especially useful when the fracture extends into the ankle joint.
• Magnetic resonance imaging (MRI) scan – These tests provide high-resolution images of both bones and soft tissues, like ligaments. For some ankle fractures, an MRI scan may be done to evaluate the ankle ligaments.
• More complex axial imaging – is rarely necessary; exceptions include triplane and pilon fractures.
• Posterior malleolus fractures usually require a CT – as the plain film underestimates the degree of impaction.
• Weight-bearing radiographs – not indicated in the acute ankle fracture in the emergency department, usually used for more stable injuries in outpatient settings
• MRI -although rarely emergently indicated is used to assess soft tissue, cartilaginous, or ligamentous injuries. It can also help to detect occult fractures.
• Ultrasound – can be used to assess for fractures as well a ligament and tendon injuries; however, results are user-dependent.[rx][rx]

Differential Diagnosis

• Rheumatoid arthritis
• Charcot joint
• Osteoid osteoma
• Ewing’s sarcoma
• Osteosarcoma
• Pathologic fracture
• Osteomyelitis
• Septic arthritis
• Osteoarthritis
• Gout
• Ankle sprain
• Achilles rupture
• Tendon dislocation

Treatment of Ankle Joint Fracture

Non-Surgical

Treatment available can be broadly

Medication

The following medications may be considered doctor to relieve acute and immediate pain

• Antibiotic – Cefuroxime or Azithromycin, or  Flucloxacillin or any others cephalosporin/quinolone antibiotic must be used to prevent infection or clotted blood remove to prevent furthers swelling and edema
•  Antidepressants – A drug that blocks pain messages from your brain and boosts the effects of endorphins (your body’s natural painkillers).
• Corticosteroids – Also known as oral steroids, these medications reduce inflammation. To healing the nerve inflammation and clotted blood in the joints.
• Muscle Relaxants –  These medications provide relief from associated muscle spasms.
• Neuropathic Agents – Drugs(pregabalin & gabapentin) that address neuropathic—or nerve-related—pain. This includes burning, numbness, and tingling.
• Opioids – Also known as narcotics, these medications are intense pain relievers that should only be used under a doctor’s careful supervision.
• Topical Medications – These prescription-strength creams, gels, ointments, patches, and sprays help relieve pain and inflammation through the skin.
• NSAIDs – Prescription-strength drugs that reduce both pain and inflammation. Pain medicines and anti-inflammatory drugs help to relieve pain and stiffness, allowing for increased mobility and exercise. There are many common over-the-counter medicines called non-steroidal anti-inflammatory drugs (NSAIDs). They include  and Ketorolac, Aceclofenac, naproxen
• Calcium & vitamin D3 – to improve bone health and healing fracture.
• Glucosamine & Diacerein, Chondroitin sulfate – can be used to tightening the loose tension, cartilage, ligament, and cartilage, ligament regenerate cartilage or inhabit the further degeneration of cartilage, ligament
• Dietary supplement -to remove general weakness & improved health

Surgery

All other types require surgery, most often an open reduction and internal fixation (ORIF), which is usually performed with permanently implanted metal hardware that holds the bones in place while the natural healing process occurs. A cast or splint will be required to immobilize the ankle following surgery.

In children, recovery may be faster with an ankle brace rather than a full cast in those with otherwise stable fractures.^[rx]

Stable fractures are those that are non-displaced. These fractures receive conservative treatment. Patients with stable fractures can be discharged with unrestricted weight-bearing as tolerated. These patients can receive a walking boot and be discharged with a plan for X-ray in 1 week if stability is uncertain. It is essential to provide extensive ED return precautions in the case of a change in the status of the injury. Return precautions should include but not be limited to: uncontrolled pain, numbness, tingling, increased swelling, and decrease or change in their ability to bear weight.

Unstable fractures include those that are displaced, have talar shift, bimalleolar, and trimalleolar. These unstable fractures get treated with open reduction internal fixation (ORIF). If the patient has multiple comorbidities and is unable to tolerate surgical repair, there is the option for casting with 6 weeks of non-weight-bearing status. The ankle would need weekly ankle X-ray and the need for thromboprophylaxis needs to be assessed depending on other risk factors. This plan would require consultation with the orthopedic surgeon.[rx][rx]

Complications

Complications following ankle fractures can occur after both conservative nonoperative management and operative management.

• Nonoperative management complications may include – compartment syndrome, dislocation, complex regional pain syndrome, limited range of motion, or inner pressure ulceration.
• Operative management complications may include – compartment syndrome, wound hematoma, impaired wound healing, dislocation, mispositioned screws, inadequate reduction, complex regional pain syndrome, malunion, malposition, impingement syndrome, limited range of motion, or arthrosis.
• A complication of ankle fracture – seen in people with diabetes is Charcot arthropathy which is also known as neuropathic arthropathy. This condition occurs when there is a progressive degeneration of the ankle joint, which leads to the destruction of the bone, increased bone resorption, which ultimately leads to deformity. Long-term complications of this may lead to ulceration, infection, or eventual amputation.
• Thromboprophylaxis – is also essential in those with ankle fractures until full mobilization to prevent the development of DVT and pulmonary embolism.[rx][rx]
• Arthritis – Fractures that extend into the joint can cause arthritis years later. If your ankle starts to hurt long after a break, see your doctor for an evaluation.
• Bone infection (osteomyelitis) – If you have an open fracture, meaning one end of the bone protrudes through the skin, your bone may be exposed to bacteria that cause infection.
• Compartment syndrome – This condition can rarely occur with ankle fractures. It causes pain, swelling and sometimes disability in affected muscles of the legs.
• Nerve or blood vessel damage – Trauma to the ankle can injure nerves and blood vessels, sometimes actually tearing them. Seek immediate attention if you notice any numbness or circulation problems. Lack of blood flow can cause a bone to die and collapse.

Prevention

These basic sports and safety tips may help prevent a broken ankle:

• Wear proper shoes – Use hiking shoes on rough terrain. Choose appropriate athletic shoes for your sport.
• Replace athletic shoes regularly – Discard sneakers as soon as the tread or heel wears out or if the shoes are wearing unevenly. If you’re a runner, replace your sneakers every 300 to 400 miles.
• Start slowly – That applies to a new fitness program and each individual workout.
• Cross-train. Alternating activities can prevent stress fractures. Rotate running with swimming or biking.
• Build bone strength – Get enough calcium and vitamin D. Calcium-rich foods include milk, yogurt and cheese. Ask your doctor if you need to take vitamin D supplements.
• Declutter your house – Keeping clutter off the floor can help you to avoid trips and falls.
• Strengthen your ankle muscles – If you are prone to twisting your ankle, ask your doctor for exercises to help strengthen the supporting muscles of your ankle.

References