Intra-articular calcaneal fractures are a significant challenge in orthopedic surgery due to the complex nature of the injury and its potential for long-term complications. The calcaneus, also known as the heel bone, is the largest of the tarsal bones in the foot, playing a crucial role in weight-bearing and movement. These fractures are typically the result of high-energy trauma such as falls from significant heights or motor vehicle accidents. Such fractures often involve the posterior facet, the most critical weight-bearing surface of the calcaneus, which complicates both diagnosis and treatment.
Understanding the Anatomy of the Calcaneus
The calcaneus is located at the rear of the foot, forming part of the ankle joint. It has four primary articular surfaces: the posterior, middle, and anterior facets that articulate with the talus, and the distal surface for the cuboid. Medially, the sustentaculum tali supports the middle facet and provides a groove for the flexor hallucis longus tendon. When a calcaneal fracture occurs, especially in the posterior facet, the alignment of these facets is often disrupted, leading to complications in both the structure and function of the foot.
Radiological assessments play a key role in evaluating these fractures. The Böhler angle, which measures the height and angle of the posterior facet, is typically reduced in the case of a calcaneal fracture. This measurement, along with the Gissane angle, helps in diagnosing the severity of the fracture and determining the appropriate treatment plan. Radiographs such as the Harris axial heel view and lateral views are commonly used to evaluate the extent of the injury, while a CT scan can provide a more detailed look at the articular surface.
Mechanism of Injury and Clinical Evaluation
The mechanism behind calcaneal fractures typically involves axial loading, where the force from the impact is transmitted directly through the calcaneus, causing it to fracture. The injury often occurs in individuals involved in high-impact activities such as construction work or motor vehicle accidents. Clinically, the patient will often present with severe pain, swelling, and an inability to bear weight on the affected foot. The skin may show signs of blisters or other signs of soft tissue injury due to the trauma.
A thorough clinical examination is essential to identify complications such as compartment syndrome, which can develop in high-energy injuries. The foot’s vascular status should be assessed, and any signs of nerve damage, particularly involving the sural or tibial nerves, must be monitored closely.
Classification of Calcaneal Fractures
Two primary classification systems are used to categorize calcaneal fractures: the Sanders classification and the Essex-Lopresti classification. The Sanders classification is based on the number of fracture lines that traverse the posterior facet and can range from non-displaced fractures (Type I) to highly comminuted fractures (Type IV). The Essex-Lopresti classification divides fractures into two types based on the mechanism of injury: joint depression fractures and tongue-type fractures, each with specific fracture patterns and treatment approaches.
Treatment Options
The treatment of calcaneal fractures can be divided into nonoperative and operative management, depending on the severity of the fracture.
Nonoperative Management
Nonoperative treatment is typically recommended for fractures that are nondisplaced or minimally displaced (less than 2 mm). This approach generally involves the use of a splint or cast, followed by a period of non-weight bearing to allow the bone to heal. While nonoperative management may be appropriate for certain fractures, it carries the risk of malunion or the development of subtalar arthritis in the long term.
Operative Management
For more displaced fractures, or fractures involving significant displacement of the posterior facet, surgical intervention is often necessary. Open reduction and internal fixation (ORIF) are the standard methods for managing displaced intra-articular calcaneal fractures. The choice of surgical approach depends on the fracture type and the condition of the soft tissues. The extensile lateral approach is commonly used for complex fractures, as it provides excellent visualization of the posterior facet and allows for accurate reduction and fixation.
Minimally invasive techniques, such as percutaneous fixation and arthroscopic-assisted reduction, have also gained popularity. These techniques involve smaller incisions and aim to reduce soft tissue trauma while achieving acceptable fracture reduction. However, these methods may not be suitable for all fracture types, particularly those with severe comminution.
Subtalar Arthrodesis
In cases of severe comminution, particularly with Sanders type IV fractures, a primary subtalar arthrodesis may be necessary. This procedure involves the fusion of the subtalar joint to restore the foot’s function when anatomic reduction of the joint surface is not possible.
Postoperative Care and Complications
Postoperative care focuses on managing swelling and ensuring proper alignment of the foot. Early mobilization and physical therapy are critical to regain range of motion and prevent joint stiffness. Weight-bearing is typically restricted for several weeks, and the patient is monitored for signs of infection, wound healing, and nerve function. The use of compression stockings or foot pumps may be recommended to reduce swelling.
Complications of calcaneal fractures can be significant, with the most common being wound healing issues, particularly in the case of open fractures or fractures involving significant soft tissue damage. Other complications include infection, nerve damage, and malunion, which may require further surgical intervention, such as corrective osteotomy or arthrodesis.
Conclusion
Calcaneal fractures, particularly those involving the posterior facet, pose significant challenges in orthopedic care. A detailed understanding of the anatomy, injury mechanism, and available treatment options is essential for successful management. While nonoperative management may be appropriate for less severe fractures, surgical intervention is often required for displaced or complex fractures. Advances in surgical techniques, including minimally invasive approaches, have improved outcomes and reduced complications. However, the treatment of calcaneal fractures remains a highly individualized process, and careful consideration of the fracture type, patient factors, and potential risks is crucial for achieving the best possible functional outcome.
