Lauge-Hansen classification

The Lauge-Hansen classification is a system used to describe ankle fractures based on the mechanism of injury.^[1] It was developed by Niels Lauge-Hansen in 1950 and categorizes fractures into distinct patterns based on the position of the foot and the type of force applied during the injury. The classification helps predict associated ligamentous injuries, guide imaging interpretation, and inform treatment decisions.

The classification system is widely used in clinical practice but has been criticized for its complexity and limited interobserver reliability. While it remains valuable for understanding ankle fracture patterns, it is often used alongside other classification systems, such as the Danis-Weber system, to improve diagnostic accuracy.

This article also discusses the signs and symptoms of ankle fractures, diagnostic approaches, and treatment strategies, offering a comprehensive overview of the condition.

History

The Lauge-Hansen classification system for ankle fractures was developed by Danish radiologist Niels Lauge-Hansen (1899–1976) in the mid-20th century. In 1948, Lauge-Hansen published a comprehensive review titled "Fractures of the ankle; analytic historic survey as the basis of new experimental, roentgenologic and clinical investigations," which analyzed historical perspectives on ankle fractures and laid the groundwork for his subsequent research.^[2][3][4]

Building upon this foundation, Lauge-Hansen conducted experimental and radiological studies to understand the mechanisms of ankle injuries. In 1950, he introduced his classification system, categorizing fractures based on the foot's position at the time of injury and the direction of the applied force. This system emphasized the relationship between specific injury mechanisms and corresponding fracture patterns, enhancing the understanding of ankle injuries.^[3][5]

Lauge-Hansen's work was pioneering, offering insights into the association between fracture patterns and ligamentous injuries. His research provided a basis for closed fracture reduction and immobilization techniques prevalent before modern surgical fixation methods. However, some studies have questioned the reproducibility of his classification system, suggesting limitations in its application.^[3][6]

Signs and symptoms

Ankle fractures can vary greatly depending on the injury type, but common signs and symptoms often include:

Pain and tenderness: Pain is usually felt around the ankle, particularly where the fracture has occurred. It can be sharp and intense, especially when trying to move the foot or put weight on it.

Swelling and bruising: The ankle may swell significantly, and bruising can develop around the injured area. This is often seen in all types of fractures but can be more severe in cases of ligament damage.

Deformity: In more severe fractures, the ankle may appear deformed or out of alignment. The foot might turn in an abnormal direction depending on the injury mechanism.

Inability to bear weight: Most people with an ankle fracture will have difficulty walking or even standing. Severe pain and instability make it hard to place weight on the affected leg.

Limited range of motion: Movement of the ankle may be severely restricted. Simple actions like flexing or rotating the foot might be difficult due to the fracture and possible associated soft tissue injuries.

Different injury mechanisms cause specific patterns of fractures, which can affect the symptoms. For example, fractures caused by supination-external rotation (SER) tend to involve damage to ligaments and may cause symptoms like instability or difficulty walking.^[7]

Diagnosis

To diagnose an ankle fracture using the Lauge-Hansen classification, doctors typically start by taking a detailed medical history and performing a physical examination. During the examination, the doctor will check for signs of injury such as swelling, pain, and deformity. They will also ask about the circumstances of the injury, such as whether the ankle was twisted or if any external force (like a fall) caused the damage.^[1]

Imaging tests, such as X-rays, are used to confirm the presence of a fracture and to determine the specific type. X-rays can show the location and severity of the break. However, in more complex cases, where ligament damage is suspected, additional imaging may be needed, such as MRI or CT scans. These scans provide detailed images of the soft tissues, such as the ligaments and tendons, which may be affected by the injury. For instance, in cases where a syndesmotic disruption is suspected (a tear of the ligament between the tibia and fibula), further imaging helps doctors assess whether surgery is necessary for stabilization.^[7]

The Lauge-Hansen classification helps doctors categorize the injury based on how the ankle was twisted or impacted during the accident. This information guides the doctor in determining the appropriate treatment, whether it is rest and immobilization for minor injuries or surgery for more serious fractures.^[1]

Treatment

Treatment for an ankle fracture, including those classified by the Lauge-Hansen system, depends on the type and severity of the injury. Stable fractures and those in people unfit for surgery, may be treated with rest, elevation, and immobilization in a splint, cast, or brace. The goal is to keep the ankle still while it heals, usually for a few weeks.^[1]

For more severe fractures or those with significant damage surgery may be necessary. This is especially true if the bone is displaced, or if ligaments (like the syndesmosis) are torn, which is common in the injury patterns described by the Lauge-Hansen classification.^[7] In these cases, doctors may use screws, plates, or pins to hold the bones in place while they heal.

Post-surgery, patients may need physical therapy to help regain strength and flexibility in the ankle. Exercises can assist with range of motion, and help prevent the joint from becoming too stiff.^[8] During recovery, it’s essential to follow the doctor’s recommendations on when to start putting weight on the ankle and how much activity is safe.

Classification

The following types of ankle fractures are classified within the Lauge-Hansen system:^[1][4][9]

Grade	Sequence	Example
Supination-Adduction	Anterior talofibular ligament sprain or distal fibular avulsion fracture Vertical medial malleolus fracture and impaction of anteromedial distal tibia	Supination-adduction ankle fracture-dislocation
Supination-External rotation	Anterior inferior tibiofibular ligament sprain Lateral short oblique fibular fracture (anteroinferior to posterosuperior) Posterior inferior tibiofibular ligament rupture or avulsion of posterior malleolus Medial malleolus transverse fracture or disruption of deltoid ligament	Supination-external rotation ankle fracture-dislocation
Pronation-Abduction	Medial malleolus transverse fracture or disruption of deltoid ligament Anterior inferior tibiofibular ligament sprain Transverse comminuted fracture of the fibula above the level of the syndesmosis	Pronation-abduction ankle fracture-dislocation
Pronation-External rotation	Medial malleolus transverse fracture or disruption of deltoid ligament Anterior inferior tibiofibular ligament disruption Lateral short oblique or spiral fracture of fibula (anterosuperior to posteroinferior) above the level of the joint Posterior inferior tibiofibular ligament rupture or avulsion of posterior malleolus	Pronation-external rotation ankle fracture-dislocation

Clinical relevance

The Lauge-Hansen classification is widely utilized to categorize ankle fractures based on the mechanism of injury. Its clinical significance lies in its ability to predict associated ligamentous injuries, guide imaging interpretation, and inform treatment decisions.

Predicting ligamentous injuries

Each fracture pattern described by Lauge-Hansen correlates with specific soft tissue injuries. For example, SER injuries typically begin with a sprain of the anterior inferior tibiofibular ligament.^[1] As the injury severity escalates, it can progress to involve a spiral fracture of the distal fibula, rupture of the posterior inferior tibiofibular ligament, and ultimately, a transverse fracture of the medial malleolus or disruption of the deltoid ligament.^[1] Understanding these mechanisms allows for a systematic approach to fracture assessment and management.

Treatment implications

The classification assists in determining the stability of the ankle joint, which is crucial for treatment planning. Stable fractures, such as isolated supination-adduction (SAD) stage I injuries, may be managed conservatively with immobilization.^[1] Conversely, unstable SER stage IV injuries, involving complete disruption of the syndesmosis and deltoid ligament, often necessitate surgical fixation to restore joint stability and function.^[1]

Additionally, recognizing the sequence of injury aids in guiding imaging studies. For instance, in suspected PER injuries, stress radiographs or magnetic resonance imaging (MRI) may be required to evaluate for syndesmotic disruption, even if initial radiographs appear normal.^[7]

Limitations and reproducibility

Despite its utility, the Lauge-Hansen classification has faced criticism for its complexity and limited inter-observer reliability. Studies have demonstrated moderate agreement among clinicians using this system, indicating potential inconsistencies in distinguishing between different stages of injury. For example, research has shown that inter-observer and intra-observer reliabilities are fair at best for the Lauge-Hansen classification.^[10][11]

Some researchers advocate for combining this system with other classification methods, such as the Danis-Weber system, which focuses on the level of the fibular fracture relative to the syndesmosis. The Danis-Weber classification has shown moderate to excellent inter-observer agreement, suggesting it may offer more consistent reliability in certain clinical contexts.^[12]

In summary, the Lauge-Hansen classification provides a structured framework for understanding ankle fracture mechanisms, which can be instrumental in predicting injury patterns and guiding treatment. However, clinicians should be mindful of its limitations and consider incorporating additional diagnostic tools to ensure comprehensive patient evaluation and management.

See also

• Danis–Weber classification
• Herscovici classification