A Rational Approach to Ankle Fractures
Section snippets
Biomechanical considerations
The ankle joint is subject to enormous forces across a relatively small surface area of contact, with up to 1.5 times body weight with gait and greater than 5.5 times body weight with more strenuous activity. Maintaining congruency of the ankle joint is therefore critical to the long-term viability of the ankle. Ramsey and Hamilton2 showed in a cadaveric model that only 1 mm of lateral translation of the talus reduced surface contact area in the ankle joint by 42%; lateral translation of 2mm
Classification
The Lauge-Hansen classification was developed in 1950 as a result of both cadaveric dissections of experimentally produced fractures, and clinical and radiographic examinations.4 Four consistent patterns were recognized: supination-external rotation, supination-adduction, pronation-abduction, and pronation-external rotation. The work was a landmark advance because it was the first classification scheme to assign a causative mechanism of injury to ankle fractures that, with the subsequent
Supination-External Rotation
The supination-external rotation (S-ER) pattern is the most common injury pattern and accounts for 40%–75% of all ankle fractures. A supination-external rotation injury includes: (I) failure of the anterior-inferior tibiofibular ligament (AITFL); (II) a spiral oblique fibula fracture at or just above the ankle mortise; (III) failure of the posterior-inferior tibiofibular ligament (PITFL) or posterior malleolus fracture; and (IV) tension failure of the deep deltoid ligament or transverse
Radiographic considerations
Certain preliminary radiographic criteria are beneficial in determining the relative stability or instability of a malleolar fracture. Coronal plane symmetry, particularly in the absence of fracture medially, can be assessed with respect to the medial and lateral clear spaces. Preservation of fibular length and the so-called “Shenton's line of the ankle” imply some degree of inherent stability (Fig. 6). Sagittal plane symmetry can be assessed with respect to the presence or absence of a
Decision-making in ankle fractures
In the event of a suspected ankle fracture, clinical evaluation includes a thorough patient history as to the injury mechanism, and the anticipated force and energy involved. The reported injury mechanism and radiographic fracture pattern are then used to classify the injury by the Lauge-Hansen classification.4 Stable injury patterns can be treated nonoperatively; unstable injury patterns are typically treated operatively.
Difficulty can be encountered in diagnosing deltoid incompetence,
General Considerations
In the absence of an open injury or irreducible dislocation, surgical treatment for an unstable ankle fracture pattern is certainly not an emergency and can therefore be completed as an elective procedure. The author prefers to delay definitive surgery for 10–14 days, until resolution of the acute inflammatory phase. This delay allows dissipation of soft tissue swelling, and in light of the limited soft tissue envelope surrounding the ankle joint, theoretically lessens the risk of wound
Supination-External Rotation
Fibular stabilization can be completed using either a dorsal anti-glide or lateral neutralization technique, typically with a simple one-third tubular plate and 3.5-mm cortical screws (Fig. 8). Although there is no overall difference in fracture healing rates or overall outcome between the two fixation methods, the dorsal anti-glide plate offers several distinct advantages, including: less prominence and thus better soft tissue coverage and lower incidence of late hardware removal;15, 16, 17
Posteromedial variant patterns
Not every fracture is classifiable by the Lauge-Hansen classification. Atypical posteromedial variant patterns have been described; the incidence of these variant fractures ranges from 6%–11%, and have been associated with both high-energy and low-energy injury mechanisms.24, 25, 26, 27 These patterns feature a supination-external rotation or pronation-external rotation pattern with the fibula laterally, and a vertical split through the posterior colliculus with posteromedial subluxation of the
Postoperative protocols
The author prefers splint immobilization for 2 weeks after surgery for all ankle fractures. The limb is then placed in an elastic compression stocking and prefabricated fracture boot and early range of motion exercises are begun. For simple patterns, the patient remains nonweight-bearing for 6 weeks postoperatively, and transitions to regular shoe-wear thereafter. Serial weight-bearing radiographs are obtained for at least 6 months postoperatively. I do not routinely remove hardware unless it
Summary
Ankle fractures involve a spectrum of injury patterns from simple to complex, such that they are not always “just an ankle fracture.” By combining the injury mechanism and the radiographic findings, the surgeon can apply the Lauge-Hansen classification in taking a rational approach to the management of these fractures. Syndesmotic instability and atypical patterns are becoming increasingly recognized, in part through the judicious use of CT scans. The goal of surgical stabilization includes
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The rationale behind surgical approaches to ankle fractures
2018, Orthopaedics and TraumaThe Cunéo and Picot fracture-dislocation of the ankle: A case report and review of the literature
2018, FootCitation Excerpt :This type of fracture is inherently unstable, even if the posterior malleolar fragment size is smaller than 25% of the articular surface. The study by Clare [21] reported that the posterior malleolus acts as a restraint against posterior translation of the talus, and fractures involving approximately 25% of the articular surface will result in posterior instability, requiring fixation. A general concern is the reliability of making this measurement from a standard lateral X-ray [22].
State-of-the-Art in Ankle Fracture Management in Chile
2016, Foot and Ankle ClinicsCitation Excerpt :Clinicians could consider starting with fixation of the medial or posterior malleolus if severe comminution or bone loss of the lateral malleolus is present. Even though some investigators have advocated fixation for high fibular fractures,1 the authors think the risk of peroneal nerve injury is too great to perform fixation of fractures at the midportion of the fibula. Occasionally, the fibula in a Weber B or a low Weber C fracture can be approached with a percutaneous or minimally invasive approach.
Open Reduction Internal Fixation Bimalleolar Ankle Fracture
2016, Case Competencies in Orthopaedic SurgeryResults of arthrodiastasis in postraumatic ankle osteoarthritis in a young population: Prospective comparative study
2013, Revista Espanola de Cirugia Ortopedica y TraumatologiaPosterolateral Approach to Posterior Malleolar Fractures: A Literature Review
2023, Foot and Ankle Specialist