What is the classification of distal tibial (lower leg bone) fractures or ankle fractures?

From the Guidelines

The classification of distal tibial fractures and ankle fractures is crucial for guiding treatment decisions and predicting prognosis, with the Danis-Weber, Lauge-Hansen, AO/OTA, and Rüedi-Allgöwer systems being the most commonly used classification systems 1.

Classification Systems

The Danis-Weber system categorizes ankle fractures based on the level of the fibular fracture in relation to the syndesmosis, with Type A fractures occurring below the syndesmosis, Type B at the level of the syndesmosis, and Type C above the syndesmosis.

• The Lauge-Hansen classification categorizes fractures based on the position of the foot and direction of force at the time of injury, such as supination-external rotation or pronation-abduction patterns.
• The AO/OTA classification is commonly used for distal tibial fractures, with type 43-A representing extra-articular fractures, 43-B partial articular fractures, and 43-C complete articular fractures.
• Pilon fractures, which involve the weight-bearing surface of the distal tibia, are often classified using the Rüedi-Allgöwer system based on articular displacement and comminution.

Importance of Classification

These classification systems help guide treatment decisions, with stable fractures often managed non-operatively while unstable or displaced fractures typically require surgical fixation 1.

• The classification also helps predict prognosis, as higher-grade fractures with articular involvement generally have worse outcomes due to the risk of post-traumatic arthritis.
• Radiographs, including anteroposterior, lateral, and mortise views, are essential for evaluating ankle fractures and guiding treatment decisions 1.
• Special scenarios, such as suspected calcaneal fractures or lateral process fractures of the talus, may require additional views, such as the axial Harris-Beath view or Broden view 1.

From the Research

Classification of Distal Tibial Fractures

• Distal tibial fractures can be classified using various systems, including the AO/OTA classification, which categorizes fractures into types A, B, and C based on their severity and location 2, 3.
• The Lauge-Hansen and AO-Danis-Weber schemes are two dominant classification systems for ankle fractures, each with its own advantages and disadvantages 4.
• Integration of these systems into one scheme involving three basic patterns with appropriate staging has been proposed, combining the pronation-abduction and pronation-external rotation injuries in Lauge-Hansen's scheme into one pronation-abduction-external rotation pattern 4.

Treatment Options

• Treatment options for distal tibial fractures include external fixation, intramedullary nailing, plate fixation, and conservative treatment with closed reduction and cast immobilization 2, 3, 5, 6.
• External skeletal fixation with minimal internal fixation has been shown to be a good method for treating all types of intra-articular pilon fractures, allowing for early mobility in the ankle joint 2.
• Internal fixation (intramedullary nailing or plate fixation) has been suggested as a preferred treatment option due to its advantages in terms of shorter mobilization time and better range of motion of the ankle joint compared to external fixation 3.
• Conservative treatment with closed reduction and cast immobilization has been shown to be an effective treatment option for nonarticular fractures of the distal third tibia, with advantages over operative methods 5.
• Below-knee cast immobilization has been proposed as an effective alternative in the treatment of distal tibial physeal fractures, including those with intra-articular involvement, allowing for increased patient mobility and early knee range of motion 6.

Outcomes and Complications

• The outcomes of distal tibial fracture treatment can vary depending on the treatment method and fracture severity, with complications such as infection, nonunion, and malunion possible 2, 3.
• The percentage of union, nonunion, and malunion can range from 90.32% to 3.22% to 6.45%, respectively, with an average time to fracture union of 14 weeks 2.
• Ankle joint arthrosis can occur as a late complication, particularly in patients with type C fractures 2.
• The final functional results based on the AOFAS score can range from excellent to bad, with 51.61% of patients achieving excellent results and 3.22% achieving bad results 2.