Ankle fractures: cases of bimalleolar fractures
Bimalleolar fractures are inherently unstable ankle injuries in which any tolerated displacement significantly increases intra-articular pressure, chondral shearing forces, and the risk of post-traumatic osteoarthritis, making surgical intervention necessary in the vast majority of cases. Affecting patients across all age groups, prompt and appropriate management is essential to optimize functional outcomes.
What is a bimalleolar ankle fracture?
A bimalleolar fracture is a fracture that affects both malleoli, the bony prominences on each side of the ankle. These structures are important for maintaining the stability of the ankle joint, functioning as a mortise and tenon system. This fracture often occurs as a result of trauma, whether violent or not, such as:
- Falls: Whether from standing height or slipping, a bad fall can cause significant twisting of the ankle.
- Car accidents: Side collisions in traffic accidents can also cause fractures of the malleoli.
- Sports: Sporting activities, especially those requiring quick changes of direction such as football or basketball, increase the risk of injury. Hikers are at risk for this type of fracture because of the possibility of the ankle and foot getting trapped in a hole.
Suspected bimalleolar fracture requires prompt plaster immobilization to reduce the risk of skin complications, and should be evaluated with X-rays to determine the appropriate treatment.
Symptoms of a bimalleolar ankle fracture
The bimalleolar fracture manifests itself through several symptoms that should catch the attention of anyone concerned. Here are some common signs to watch for:
- Intense pain: This pain, usually felt around the ankle, can become stronger when you move or press on the area. However, some patients are still able to walk on their fracture.
- Swelling: You may notice significant swelling around the ankle, which can become red and warm to the touch. This is a sign of inflammation that should be taken into account.
- Difficulty walking: People affected by this fracture often have trouble placing their foot on the ground, which can complicate their mobility and independence.
- Deformity: Sometimes, a visible deformity of the ankle may appear, which can indicate significant displacement of the fracture or even an associated dislocation.
If you experience these symptoms following an ankle injury, it is necessary to consult without delay. An early diagnosis and appropriate treatment can really make a difference to functional recovery.
Diagnosis of a bimalleolar ankle fracture
The diagnosis of a bimalleolar fracture begins with a clinical examination, performed by a qualified healthcare professional. Pain and ankle mobility are assessed, followed by a visual inspection to identify any ecchymosis or edema.
Palpation of the malleoli is then carried out to localize areas of tenderness. Finally, neurovascular function is evaluated to confirm adequate blood circulation and rule out any nerve involvement. These steps are essential to guide the diagnostic process and determine the severity of the injury.
Medical Imaging
After the clinical examination, medical imaging is often necessary to confirm the diagnosis and tailor the treatment of the fracture. Here are the techniques used:
- Standard X-rays: These tests are generally the first performed to visualize fractures. They make it possible to identify the presence of fractures, their type, and their precise location.
- CT scan: In more complex cases, a CT scan may be ordered to obtain cross-sectional images of the ankle, providing additional details about the condition of the bones and surrounding tissues. It allows a more accurate assessment of the fracture, any displacement, and the presence of articular splits. It is very useful for analyzing trimalleolar fractures.
- MRI: Although less frequent for a bimalleolar fracture, MRIs may be requested to examine the soft tissues, such as ligaments or tendons, that may also have been injured.
These imaging techniques are essential for establishing a precise diagnosis and guiding the treatment to achieve the best possible result.
Treatment of a bimalleolar fracture
Exceptionally, a non-surgical treatment is offered to treat a bimalleolar fracture. This option is often chosen when the fracture is strictly non-displaced and stable. Orthopedic treatment is based on:
- Immobilization: Immobilization can be achieved using a cast, a walking boot, or a splint. A plaster cast is necessary for 45 days to limit the risk of secondary displacement of the fracture.
- Rest: It is recommended not to put weight on the injured ankle to allow optimal healing.
- Use of splints: Splints or orthoses are frequently used to stabilize the ankle and reduce pain.
- Application of ice and elevation: Applying ice to the swollen area and elevating the ankle helps reduce inflammation.
- Anti-inflammatory medications: These treatments can relieve pain while reducing swelling.
Orthopedic treatment requires regular radiological follow-up to ensure that there is no displacement of the fracture under the cast. If there is no displacement, orthopedic treatment is continued. In the event of secondary displacement, surgical treatment is proposed.
Surgical intervention
When the fracture is more complex or orthopedic treatment is not indicated, surgical intervention is necessary. Here are some situations that may require surgery:
- Displaced fractures: When the bones are no longer aligned.
- Joint instability: If the ankle shows noticeable instability with a loss of congruence of the articular surfaces.
- Fracture-dislocation: Risk of loss of blood supply to the fractured bones.
- Open fracture: Major infection risk and guarded joint prognosis.
Common surgical procedures include internal fixation, which uses plates and screws to stabilize the bones, as well as ankle arthroscopy, a less invasive approach. The goal of these interventions is to restore the correct alignment of the bones and promote optimal recovery of ankle function.
Our approach to a bimalleolar ankle fracture
Bimalleolar ankle fractures encompass several subtypes depending on the fibular fracture pattern and the associated lesion of the medial malleolus or internal ligamentous complex, excluding trimalleolar fractures which involve an additional posterior tibial plafond fracture. Given the inherent instability of these fractures and the significant risk of secondary displacement and malunion, surgical management is indicated in virtually all cases, as orthopedic treatment is considered inadequate.
Anterior ankle arthroscopy is systematically performed intraoperatively to evacuate the intra-articular hematoma, address associated ligamentous and chondral lesions, ensure accurate fracture reduction, and assess syndesmotic stability. Postoperatively, cast immobilization is maintained for 45 days to allow complete osseous and ligamentous healing.
This fracture involves a fracture of the medial malleolus and a fracture of the fibula (or peroneus) below the syndesmosis ligaments. Fixation of the medial malleolus, generally by screwing, is systematically performed. The subligamentous fibular fracture can be left without fixation if it is stable; otherwise, it will be stabilized by an intramedullary screw. In this case, arthroscopy enables the evacuation of the intra-articular hematoma, evacuation of osteochondral debris, and the analysis and possible repair of the ligament if necessary.
This fracture involves a fracture of the medial malleolus and a fracture of the fibula (or peroneus) at the level of the syndesmosis ligaments. It is estimated that there is a 30% risk of associated syndesmotic injuries with these fractures. Fixation of the medial malleolus is systematically performed. The fibular fracture is systematically osteosynthesized using a screwed plate.
Ankle arthroscopy enables evacuation of the intra-articular fracture hematoma and examination of the syndesmosis, which may be unstable in the mediolateral or sagittal plane. Any instability of the syndesmosis will require stabilization, usually with a double-button system, passing through a hole in the plate screwed to the fibula. The stability of the syndesmosis will again be checked by arthroscopy after stabilization.
This fracture involves a fracture of the medial malleolus and a fracture of the fibula (or peroneus) above the syndesmosis ligaments. Generally, the syndesmosis ligaments are injured in this type of fracture, as well as a portion of the interosseous membrane, which ensures the stability and transmission of forces from the two leg bones to the ankle.
The fibular fracture as well as the fracture of the medial malleolus are systematically osteosynthesized, and the syndesmosis is stabilized using a double-button system. Ankle arthroscopy enables evacuation of the intra-articular fracture hematoma and evaluation of the syndesmosis stability after stabilization.
This fracture does not involve a fracture of the medial malleolus but rather a more or less significant lesion of the internal ligamentous complex, associated with a fibular fracture, which may be supraligamentous, interligamentous or, more rarely, subligamentous.
The fibular fracture is systematically stabilized; ankle arthroscopy in this case allows assessment of the internal ligamentous lesion, its extension, and its severity. Arthroscopy allows evacuation of the intra-articular fracture hematoma and repair of internal ligamentous lesions if they are accessible by arthroscopic means. In the case of major injuries, an open ligament reinsertion is performed.
The trimalleolar fracture corresponds to a bimalleolar fracture associated with a posterior marginal fracture of the tibial plafond. This fracture does not strictly fall under bimalleolar fractures, although it is commonly considered part of them. For us, any posterior marginal fracture of the tibial plafond associated with bimalleolar fractures must be osteosynthesized, regardless of its size.
This posterior marginal fracture of the tibial plafond corresponds to a syndesmotic injury in 100% of cases, it must be initially fixed by a posterior approach to the ankle. The posterior marginal fracture is thus stabilized, generally using screws, and the fibular and medial malleolus fractures are also fixed. Syndesmosis is stabilized with a double-button system. Ankle arthroscopy allows the evacuation of the intra-articular fracture hematoma and evaluation of the stability of the syndesmosis after stabilization.
Rehabilitation after a bimalleolar fracture
Rehabilitation after a bimalleolar fracture plays a key role in your recovery. By following a rehabilitation program, you can:
- Regain mobility in your ankle, an essential step to resume your daily activities.
- Strengthen the stabilizing muscles of the ankle, which may have weakened during the immobilization period.
- Prevent joint stiffness that can occur after a long period of inactivity.
- Reduce the risk of new injuries by improving the stability of your ankle.
Recommended Exercises
Once your doctor has given you the green light, it is time to incorporate specific exercises to boost your recovery. Here are some suggestions:
- Plantar flexion and ankle extension: Sit comfortably with your leg extended. Flex your ankle towards you, then extend it away from you.
- Ankle rotation: While sitting, lift your leg slightly and make circles with your foot, first in one direction, then in the other. This exercise helps improve your mobility.
- Balance on one leg: Stand near a wall or a chair for support, then try to balance on one leg. This strengthens your ankle proprioception.
- Toe raises: Stand up, rise onto your tiptoes, then slowly lower yourself to strengthen your calves.
- Posterior chain stretches: Stretching the calf and hamstring muscles is very important to limit intra-articular pressure in the ankle, shearing forces on the cartilage, and the risk of ankle sprains.
Be sure to perform these exercises gradually, listening to your body and respecting any pain sensations. Good rehabilitation can really make a difference in your return to normal.
A bimalleolar ankle fracture is a common fracture in both the more athletic and the more sedentary individuals. These are articular fractures with cartilage damage that most often require surgical stabilization of all the fractures and ligament stabilization in case of injury. Ankle arthroscopy is systematically performed during the surgical management of these fractures. In case of a non-operated fracture or insufficient surgical treatment, the risk of ankle osteoarthritis in the short and medium term is high.