Introduction

The talus bone is part of the group of bones that make up the ankle, located between the bones of the lower leg (tibia and fibula) and the heel bone (the calcaneus).¹ These bones that surround the talus are attached to it by ligaments, which help to stabilise the ankle joints.² The talus is very important in supporting the movement of the foot and ankle, as well as distributing the forces from body weight to the foot.² As having a talus fracture can cause great pain, chronic discomfort, and constant effects on your daily life and function,1 it is vital that it is detected by healthcare professionals. This will ensure accurate diagnoses, and the best course of action for treatment is not to delay recovery. 

What are talus fractures?

Talus fractures occur when the talus bone breaks due to a strong external force.¹ The fracture can occur at different areas of the talus bone: head, neck or body.³ Around half of talus fractures happen at the neck of the bone, as it is the weakest part, and fractures in this area are classified into 4 types depending on how much the bones have moved out of their normal position.³ Common causes of talus fractures are high-energy trauma, such as vehicle collisions, falls from great heights, or accidents from sports and exercise, especially snowboarding.¹

Although talus fractures contribute to less than 1% of all bone fractures and 3-6% of foot fractures,⁴ it can still be a difficult, painful and serious injury. If you have a talus fracture, you may experience acute pain, swelling, bruising and tenderness in your foot and/or ankle.¹ You may also have trouble walking or bearing weight on your foot.¹

How are talus fractures diagnosed?

There are several ways that talus fractures can be diagnosed, through a series of sequential processes. Typically, your doctor will examine the site of injury and order some scans.¹ This will allow an appropriate diagnosis and the most suitable treatment plan.

Clinical examination¹

When a talus fracture occurs, you may need to go to the emergency department to receive urgent care. During your first visit to the doctor, they will look at your ankle in a physical examination to detect swelling, bruising or cuts on your skin. Further examination of mobility will be conducted to reveal if you have trouble moving the ankle and your toes or bearing weight on your foot. They may check the sensitivity of the bottom of your foot, in case nerves surrounding the fractured bone are also damaged. To ensure there is still adequate blood flow to your foot and toes, your doctor may check the pulse in your foot. Immediate action may be needed if there is increasing pressure caused by a build-up of fluid in your leg, leading to a loss of feeling and function in the leg.¹

Your doctor may also ask you some questions about the cause of the injury and symptoms that may not be easily visible.⁵ It is important to have the first initial clinical examination to take note of other injuries that may be present.

X-rays: the first look inside^1,6

In X-rays, radiation is emitted from a machine, which then passes through the body and produces an image by the detector on the other side. Different parts of the body will absorb the radiation at different rates, and so, X-rays can create contrasting images that show bones and some organs inside your body.^1,6 They are taken by healthcare professionals called radiographers, and the results are examined by specialist radiologists.⁶ X-rays are a quick and non-invasive technique employed to detect fractures and the position of the fracture. It is painless and usually no preparation is required.⁶

However, sometimes X-rays may not be enough to detect a talus fracture. As only 2-dimensional images are created, small and incomplete fractures may not show in obvious ways where parts of the bones are misaligned.⁷ In these cases and when your doctor may need more information about your injury, more advanced imaging will be needed to make sure a fracture is not missed or misdiagnosed.¹

Advanced imaging: CT scans^7,8

Computed tomography scans, also known as CT or CAT scans, can give a more detailed image of the inside of the body. During a CT scan, you will lie flat on a bed whilst the scanner takes the images. CT machines emit X-ray radiation in a circular motion around the body to create multiple 3-dimensional images, and the information is sent to a computer, which will allow visualisation of these images by healthcare professionals.⁸ Similar to X-rays, CT scans are painless, but the procedure will take a longer time, 10-20 minutes, and you will need to be injected with a dye so that a contrasting image can be seen in the scans.⁸ This can be through an injection, ingesting it as a drink, or the dye can be put in your bottom. The dye will pass through in your urine.⁸

Although taking an X-ray for talus fractures is a quick and helpful process to discover talus fractures, CT scans are often needed to see the injury in the talus bone in more detail.⁸ This will help to gain more accurate information about the type, location and severity of the fracture, particularly those that are small and hidden in X-rays scans.⁷ Once there is more understanding of the nature of the talus fracture, then your doctor can plan for the best treatment for you, especially if surgery is needed and for its planning.^1,8

Other advanced imaging options

MRI, magnetic resonance imaging, is another advanced imaging technique that uses magnetic fields and radio waves.⁹ Different tissues have distinct signalling patterns when going through a strong magnetic field, and can create sophisticated and detailed images of the inside of the body.⁹ They are not commonly used for talus fractures, but they may be used when the fracture cannot be seen in X-rays or CT scans, or if an osteochondral fracture is suspected.¹⁰ This is when the talar dome, which is the top of the talus bone where there is a layer of cartilage covering it, breaks off.¹¹ MRI scans may also be considered if there is persistent pain at the site of injury.¹²

Why is an accurate diagnosis so crucial?

Treatment is based on diagnosis and the severity of the fracture, so having an accurate diagnosis is instrumental for effective treatment and optimal recovery.¹ Stable fractures, where the bones have not come out of their normal position, will be given a cast to ensure the bones are held in place without misalignment.¹ More complex talus fractures will need surgery when the bones have come out of place to realign them.¹ Metal screws and plates may be used to hold them together.¹ Recovery will take at least 2-8 weeks, but the more severe the fracture, the longer it will take to fully recover.¹ During this time, it is highly recommended that plenty of rest is taken to avoid putting weight and pressure on the injured ankle.¹ Follow-up scans and physiotherapy may be needed to make sure the bones are healing properly and function is regained.¹

Sometimes, talus fractures may be missed or misdiagnosed. For example, 50% of talus fractures are mistaken for ankle sprains.¹³ When an accurate diagnosis has not been made, there may be long-term and painful consequences. Complications such as the death of the bone tissue due to the affected blood supply to the area and arthritis in the talar joints can occur if timely interventions are not made. This will not only delay bone healing but also induce great pain, disability, and require surgical operations again.¹⁴ 

Summary

The talus bone in your ankle has a huge role in shifting weight from your body to your foot. When an injury occurs, it is very important to promptly and accurately diagnose talus fractures and their severity. Your doctor will usually clinically examine the injured site and order some scans. This may include a series of X-rays and CT scans. Less commonly, more advanced imaging, like MRI, may also be used. This will help decide which treatment is best for the type of fracture present and provide the optimal outcome.