What Is Trimalleolar Fracture

Introduction

The ankle, a critical joint connecting the lower leg to the foot, comprises the tibia, fibula and talus bones. Our ankles can move in multiple directions, acting much like a hinge thanks to a joint known as the talocrural joint. Ligaments – medial, lateral and syndesmotic – play a pivotal role in maintaining ankle flexibility and stability and are supported by various components such as cartilage, muscles, nerves and blood vessels.1 A trimalleolar fracture refers to a three-part fracture of the ankle involving the medial malleolus, the lateral malleolus and the posterior malleolus. Each of these structures corresponds to the inner end of the tibia, the outer end of the tibia and the back part of the tibia, respectively.2 This is an injury that is typically sustained from high-impact sports or accidents and can present with painful symptoms such as swelling and bruising. While it is the least common type of ankle fracture, it is treated in the same way as most, with major surgery to reset the bones back in place. Post-operative physiotherapy is also part of the treatment and is associated with the best outcomes. It can be a lengthy journey, but it is possible to regain full mobility and function in the affected ankle. 

Anatomy of the Ankle

The ankle joint is formed where the talus, tibia (shin) and fibula (calf) bones join together.3 This joint connects your lower leg to your foot, and it is sometimes referred to as the talocrural or tibiotalar joint. The ankle joint is considered to be a synovial joint, which means it has a lot of freedom to move - your ankle acts as a hinge that moves in multiple directions. The ligaments in your ankle are important, and they come in three main sets: medial, lateral, and syndesmotic. Each of these ligaments connects various bones together in order for your ankle to move properly. There are many other components in the ankle joint, such as cartilage, muscles, nerves and blood vessels, that all serve to help your ankle bend and flex to keep you stable and maintain balance.⁴ 

Signs and symptoms

This type of fracture usually occurs from high-impact sports injuries but can also occur with car accidents and even a simple fall or trip. If left untreated, this type of fracture can cause the bones to shift, break into smaller pieces, and even misalign the ankle joint. All of these things can lead to a condition called osteoarthritis and can make your ankle problems significantly worse.⁵ Some of the symptoms of a trimalleolar fracture include:⁶

• Sudden pain in the ankle that can be quite severe 
• Inability to put any weight on the ankle and difficulty walking 
• Bruising on and around the ankle 
• Severe swelling 

The NHS advise seeking help from NHS 111 if you’ve injured your ankle and:⁷ 

• Are experiencing severe pain that is getting progressively worse 
• Large amounts of swelling and bruising are getting worse 
• It feels extremely stiff 

They also advise visiting A&E if:

• Your ankle is at an odd angle/has bone(s) sticking out 
• There is a bad cut/wound 
• Your toes are blue or white and feel numb 

While you’re waiting to be seen/treated for an ankle fracture, it is important to take precautions to prevent the injury from getting any worse. You should:⁷ 

• Keep the injured ankle raised 
• Ice the ankle every 2-3 hours for 15-20 minutes 
• Make sure to stop any bleeding if applicable, by putting pressure on the world using a dressing or a clean cloth. 
• Wrap the ankle in a loose bandage to help support the injury, provided it is not sticking out at an odd angle. 
• Remove any accessories or jewellery on ankles, toes and feet 
• Take painkillers such as ibuprofen or paracetamol to relieve the pain
• Refrain from eating or drinking in case you require surgery 

Diagnosis

There are a few types of ankle fractures you can acquire due to the composition of multiple bones. Some other common fractures include:

• Lateral malleolus fracture - this is considered to be the most common type of ankle fracture and involves breakage of the bony prominence on the outside of the ankle⁸ 
• Bimalleolar fracture - much like the lateral malleolus fracture, this type involves breakage of the bone on the inside of the ankle⁹ 
• Pilon Fracture - this is an injury acquired through higher impact, such as falling from a height, and involves a break in the central portion of the lower tibia¹⁰ 

Each of these fractures, including a trimalleolar fracture, presents with similar symptoms of pain and swelling and can only be differentiated using various imaging techniques. 

Imaging techniques 

The initial assessment of a trimalleolar fracture is done using conventional X-rays to take images of the foot and ankle side on. This can provide information about the ankle joint to see if it is misaligned and look for any fractures.¹¹ If a doctor needs more detailed information, a CT scan can be used to give precise measurements about the fracture size and how the bones are broken.¹² The different types of trimalleolar fractures can be classified using information based on the CT scans.¹³ However, these types of scans are not typically favoured due to the high cost and exposure to radiation. Many researchers argue that conventional X-rays are adequate diagnostic tools.¹⁴ An MRI scan can also be used to evaluate any damage to the ligaments, and stress tests using X-rays can help to check if surgery is necessary.¹⁵

Treatment options

Open reduction internal fixation surgery 

Most trimalleolar fractures are treated with ORIF surgery - Open Reduction Internal Fixation. This is a major surgery where the broken bones will be put back together using screws, plates, sutures, and rods.¹⁶ The reduction part of the surgery is when doctors will line up your ankle’s broken pieces and use various tools to internally fix them into place. Preparation for the procedure involves avoiding food and drink so your body is clear of liquids at least 6 hours before.¹⁷ 

The risks associated with ORIF surgery 

The recovery process following ORIF surgery can be painful. It can also harbour infection and a risk that the broken ends of the bone don’t connect properly after the procedure. This potential complication is known as malunion, where the fractured bone can move during recovery and heal in a different position, which would require another surgery to fix.¹⁸ Another possibility to be aware of is the increased risk of developing osteoarthritis - while this isn’t particularly common it can cause increased joint pain and tenderness. This is due to cartilage damage and the weight-bearing shifts associated with the injury. There isn’t a cure as such for this phenomenon; however, icing, anti-inflammatory medication, and extended physical therapy can help lessen the symptoms.¹⁹ 

Recovery and rehabilitation

The stages of recovery for an orthopaedic injury consist of 3 phases: acute, subacute and chronic. The acute phase happens immediately after the injury is obtained and lasts 4 days. Subacute phases follow from this, lasting between 4 to 14 days, and finally, you enter the post-acute phase, which is typically 14 days after injury.²⁰ The physical therapy to treat a trimalleolar fracture can start between 2-4 weeks from the initial break. Treatment starts by focusing on reducing pain and swelling and eventually will address regaining full mobility back. Your care provider will walk you through exercises to strengthen your core and lower extremities. The process can be lengthy in restoring strength, muscular endurance, and a sense of joint position and movement in the ankle.⁹ Some of the other less severe ankle fractures are observed to have nearly 80% recovery within 6 months of injury.²¹ However, a trimalleolar fracture can be a severe injury to sustain and is one of the least common fractures. Someone with such a fracture can expect drastic life changes for several months. It is possible to regain full function of the ankle with proper rehabilitation; however, this can take up to a year.⁹ The amount of time it takes to heal in full depends on how stable your bones are and the extent to which the injury affects the surrounding joints.¹⁵ 

Summary

An ankle fracture, particularly the complex trimalleolar type, demands careful attention. Diagnosing these fractures involves various imagining techniques, with X-rays offering initial insights and CT scans providing more precise details for classification. Treatment often involves ORIF surgery, a rigorous procedure with potential risks such as malunion and, in rare cases, osteoporosis. From acute, subacute and chronic phases of recovery, physical therapy after 2 weeks can help to regain mobility and strength. Patience and consistency in care are essential for full recovery, which can take up to a year, depending on the fracture’s severity and its impact on the surrounding joints' stability.