Cuneiform bone fracture

Anatomy of the cuneiform bones

The cuneiform bones are three small bones located in the middle of our foot, between the navicular and the metatarsals. The joint between the navicular and the 3 cuneiforms is called "the inominée." The joint between a cuneiform bone and the base of its corresponding metatarsal is called the cuneometatarsal joint; there are 3 cuneometatarsal joints. There are 3 cuneiform bones:

• Medial cuneiform (1st cuneiform) : this is the largest of the three, and it supports the first metatarsal.
• Intermediate cuneiform(2nd cuneiform) : of modest size, it is located between the medial and lateral cuneiforms; it is linked to the base of the 2nd metatarsal, which is wedged in.
• Lateral cuneiform (3rd cuneiform) : this is the smallest one, and it supports the third metatarsal; triangular in shape with a dorsal base, it works like a piston. Its lowering helps lock the foot during walking.

These bones play an important role in the structure and biomechanics of the foot, contributing to its stability and its adaptive mobility on uneven ground.

Role of the cuneiforms in foot biomechanics

The cuneiform bones perform several essential functions:

• Force transmission : They help distribute loads between the front and back of the foot when we walk or run.
• Stability : By forming joints with the navicular and metatarsals, they contribute to locking/unlocking the foot during walking.
• Mobility : Their position allows for adaptive mobility on various terrains, which is crucial for the foot's complex movements.

Understanding the anatomy of the cuneiform bones is very useful for better understanding injuries that can occur, such as fractures.

What is a cuneiform bone fracture?

A cuneiform fracture is a bone injury that affects one or more of the three cuneiform bones present in each foot. These bones, located between the tarsus and the metatarsals, are essential to ensure the stability and mobility of our foot. Cuneiform fractures are frequently associated with injuries known as Lisfranc injuries.

Cuneiform fractures can occur for several reasons, including:

• Direct trauma: Severe blows, such as a fall or an accident occurring during sports activity, can cause fractures.
• Repetitive stress: Intense physical effort, such as running without adequate preparation, can cause stress fractures.

These fractures are classified according to their type and associated injuries. For example, a distinction is made between non-displaced fractures, where the bone fragments remain aligned, and displaced fractures, which often require surgery to realign the bones properly. In Lisfranc injuries, the cuneiforms may be fractured, but ligament injuries are more common, corresponding to potential instabilities of the intercuneiform joints.

Causes of cuneiform bone fractures

Fractures of the cuneiform bones can be of several types, both traumatic and microtraumatic.

Traumatic injuries

Direct traumas are often among the main causes of cuneiform fractures. Here are some common situations:

• Road accident: Road traffic accidents, generally high-velocity, can cause Lisfranc injuries and therefore cuneiform fractures.
• Sports accidents: High-impact sports, such as football or basketball, can cause fractures due to sudden movements and impacts.
• Crush injury: If a heavy object crushes your foot, this can lead to cuneiform fractures, which may also be associated with soft tissue injury.

Fatigue fractures, stress fractures, or insufficiency fractures

Fatigue fractures often occur as a result of repeated abnormal trauma to the bones, usually related to repetitive sports or professional activities. This type of injury often concerns:

• Athletes: Intensive training without sufficient rest can weaken the bones and increase the risk of fractures.
• Manual workers: Those performing repetitive tasks are also at risk.
• Changing activities: Rapidly switching to a more intense physical activity without preparation can lead to fractures.
• Military personnel: Due to high physical demands and very rigid footwear, military personnel are prone to fatigue fractures. American military personnel are frequently the subject of high-quality studies on Lisfranc injuries, as they represent a large cohort.

Associated symptoms

One of the most common symptoms of a cuneiform bone fracture is intense pain, localized at the instep. This pain, which can be described as sharp and persistent, becomes particularly troublesome when walking or when pressure is applied to the foot. It then makes it difficult to carry out daily tasks. At the same time, a noticeable swelling is common, and a foot deformity is visible. This swelling is generally due to a build-up of fluid caused by inflammation. It is important to pay attention to these signs, as they may require appropriate medical care. If you experience these symptoms, do not hesitate to consult a specialist for advice on foot care in the event of a fracture. Any large, painful foot after trauma with a normal radiographic assessment should have a CT scan to look for injuries to the cuneiforms and especially the Lisfranc joint.

Limited mobility

Another associated symptom of cuneiform bone fracture is difficulty moving the foot. You may have trouble performing normal movements, such as walking or simply standing. In some cases, you may feel instability when trying to put weight on your foot, which increases the risk of falls.

Fracture diagnosis

The diagnosis of a cuneiform bone fracture begins with a clinical examination:

• Patient interview: Analyzing the injury mechanism and its kinetics is crucial for the physical examination and subsequent imaging assessment.
• Assessment of symptoms: The first step is to identify pain, swelling, or bruising in the foot area.
• Visual inspection: Careful observation for deformities or visible abnormalities may suggest a fracture.
• Palpation: Gently touching the foot helps to pinpoint the pain and assess the sensitivity of suspicious areas.
• Mobility test: Major limitation of movement in the presence of visible deformity should lead to suspicion of severely displaced fractures or dislocations.

Medical imaging

To confirm the diagnosis, different medical imaging techniques are available:

• Standard radiographic assessment: This is the first step to visualize fractures and analyze joint relationships.
• MRI (Magnetic Resonance Imaging): This method is particularly useful for detecting fractures that are not visible on X-rays, especially in cases of insufficiency fractures. It also allows analysis of ligament injuries at the cuneiforms and Lisfranc joint.
• CT scan (Computed Tomography) or scanner: This imaging technique provides a precise view of the bone structures. It is invaluable for planning appropriate treatment, providing essential information on the complexity and extent of the injuries.

Treatment of cuneiform bone fractures

The treatment of cuneiform bone fractures depends on the severity of the fracture and any associated injuries. Practitioners generally have two main options available: non-surgical methods and surgical interventions.

Non-surgical treatment

For non-displaced or minimally displaced fractures, non-surgical treatment is often recommended:

• Immobilization: The use of casts or walking boots helps stabilize the foot during bone healing while limiting the risk of secondary displacement of the fracture.
• Rest: It is important to limit activities that might strain the foot during healing.
• Application of ice and elevation: Applying ice and elevating the foot can help reduce swelling and relieve pain.
• Medications: Non-steroidal anti-inflammatory drugs (NSAIDs) are often prescribed to relieve pain.

Surgical treatment

In cases of more complex injuries, a surgical intervention may be necessary. Here are the procedures considered:

• Open reduction and internal fixation: This standard open surgical technique involves realigning and repositioning the bones and then fixing them with plates and screws, thereby promoting optimal healing for better foot function.
• Percutaneous fixation: This is a surgical technique that uses small incisions to stabilize fractures with pins or screws. The reduction of the fractures is done with external manipulation, without opening.
• External fixation: In certain situations, an external, visible device can be used to stabilize the fracture without requiring a major incision.
• Arthroscopy: A renowned Chinese surgeon has described many arthroscopic surgical techniques, especially treating Lisfranc and cuneiform injuries using arthroscopy.

Rehabilitation and recovery

Rehabilitation is essential for proper recovery after a cuneiform bone fracture. It is not limited to restoring mobility and strength in the foot, but also plays a role in preventing long-term complications. A well-designed rehabilitation plan can truly make a difference by helping you to:

• Relieve pain and reduce inflammation.
• Regain your range of motion.
• Strengthen the muscles around the joint to provide better support.

Recommended exercises

To support your rehabilitation process, here are a few exercises that can be very helpful. They should be adjusted according to your healing progress and your healthcare professional's advice. Here are some suggestions:

• Gentle stretching: These exercises help maintain the flexibility of your tissues and relieve joint pressure.
• Muscle strengthening: Using resistance bands can help strengthen the muscles in your foot and ankle.
• Proprioception exercises: Work on your balance by standing on one leg or using an unstable cushion.
• Progressive walking: Start with short distances and gradually increase the intensity.

To optimize your recovery and ensure a return to normal function, it is important to practice these activities regularly.

Possible complications

After a fracture of the cuneiform bones, it is possible to encounter various complications that can leave long-lasting aftereffects. Here are some of them:

• Chronic pain: Some people experience pain that persists even after the fracture has healed. This pain can become debilitating over time and significantly affect quality of life.
• Reduced mobility: The ability to perform usual movements may be impaired, thus impacting walking and balance. A decrease in mobility can also increase the risk of falls.
• Osteoarthritis: It is possible for patients to develop osteoarthritis in the joint, due to the destabilization caused by the fracture, or other bony deformities such as tarsal boss which can affect the biomechanics of the foot.

Risk of recurrent stress fractures

Risks of recurrence exist in the case of stress fractures, especially if the contributing factors are not corrected:

• Repeated trauma: Quickly resuming intense activities without proper rehabilitation can lead to new injuries. It is therefore better to take a gradual approach to regaining your abilities.
• Insufficient bone healing: If the fracture is not sufficiently healed, the risk of a refracture is significant. It is therefore wise to consult a healthcare professional regularly for follow-up.
• Biomechanical factors: Posture problems or foot biomechanics issues can increase the chances of recurrent fractures. An evaluation by a specialist can help correct these imbalances.
• Technical factors: We emphasize that footwear must be appropriate for each physical activity performed, and shoes should be changed regularly depending on the deterioration of their mechanical quality.

Precautions to take

To avoid cuneiform bone fractures, it is important to adopt a few simple yet effective prevention practices:

• Muscle strengthening: Incorporate regular exercises to strengthen the muscles in your feet and ankles. This will not only improve your stability, but also reduce your risk of falls.
• Appropriate footwear: Choose shoes that provide you with comfort and support according to your activities. Avoid high heels and slippery soles, which can compromise your balance.
• Warm-up: Before any physical activity, take time to warm up properly. This prepares your muscles and joints and thus reduces the risk of injury.
• Stretching: Ideally, a stretching session for the muscles used during activity should be done after each workout.

Importance of consulting a specialist

It is always wise to consult a specialist if you feel persistent pain or if you have suffered trauma to the foot. Here are some reasons to do so:

• Accurate diagnosis: A healthcare professional will be able to establish a clear diagnosis and assess the severity of your injury. This is essential for effective treatment.
• Treatment plan: They can offer you a personalized treatment plan, including rehabilitation options suited to your individual situation.
• Regular follow-up: Medical follow-up is essential to monitor your healing process and adjust treatment if necessary. This ensures optimal recovery and helps prevent possible complications.

Prevention and medical follow-up play a key role in maintaining the health of your feet and preventing long-term complications. By incorporating these practices into your daily routine, you can significantly reduce the risk of fractures and improve your overall well-being.