Tillaux Fracture

Stability of the ankle is due to a combination of its bony architecture, joint capsule, and ligaments. The syndesmosis is stabilized by the following four ligaments:

• Anterior tibiofibular ligament
• Posterior tibiofibular ligament
• Transverse tibiofibular ligament
• Interosseous membrane

The anterior tibiofibular ligament originates on the anterolateral surface of the tibia and runs obliquely and inferiorly to the distal fibula. The posterior tibiofibular ligament originates on the posterolateral tubercle of the tibia and inserts on the posterior fibula. It is stronger and thicker than its anterior counterpart. Because of this difference, torsional forces in adults usually cause an avulsion fracture of the posterior tibial tubercle, leaving the posterior ligament intact while the weaker anterior tibiofibular ligament usually ruptures (Tillaux lesion).

In children, ligaments usually are stronger than the physis, thereby causing avulsion injury of the distal anterolateral tibial epiphysis (Tillaux fracture) rather than rupture of the ligament itself.

The ossific nucleus of the distal tibial epiphysis appears from age 6-10 months. By age 14-15 years, the entire lower end of the tibia is completely ossified. It unites with the diaphysis at about age 18 years. The lower epiphysis contributes to about 45% of the growth of the tibia.

Kleiger et al reviewed children undergoing skeletal closure. They showed that fusion in the distal tibial epiphysis occurs first in the middle third of the epiphysis, next in the anteromedial epiphysis, then in the posteromedial epiphysis, and finally in the lateral portion of the epiphysis, with the entire process taking about 12-18 months.[4]

Closure also appears to start posteriorly in the epiphysis and then to progress anteriorly. A Tillaux fracture occurs after the medial part of the physis has fused but before the lateral part closes. The fracture line passes proximally in a vertical direction through the epiphysis and then exits laterally on the lateral cortex of the tibia. The fracture fragment rotates anterolaterally; the displacement usually is minimal but occasionally is marked.

The more skeletally mature the child, the more lateral the vertical fracture line. Therefore, the physeal injury is a Salter-Harris type III fracture of the lateral part of the distal tibial epiphysis.[2] The fibula, which is pliable, usually does not fracture. The anterior and the posterior tibiofibular ligaments remain intact.

Tillaux fracture usually is caused by low-energy trauma. It commonly is associated with skateboard and baseball (sliding) injuries. Around age 12-14 years, a forced lateral rotation of the foot in neutral or supination or a medial rotation of the leg on the fixed foot usually is responsible for an avulsion injury to the lateral epiphysis.[5, 6]

The anterior tibiofibular ligament is attached to the lateral epiphysis, the fragment being displaced anteriorly and laterally. As the foot is externally rotated, the talus appears to exert a compression-torque stress that propagates a crack through the articular surface up to the growth plate, which then shears off. The injury may be accompanied by a separate posterior metaphyseal fragment as a variant of the triplane fracture.

Ligamentous injuries are rare in children because ligaments are stronger than the growth plate that frequently is injured. In adults, the distal tibial tubercle is avulsed off the anterolateral aspect of the distal tibia (Tillaux fracture), or the anterior tibiofibular ligament may rupture (Tillaux lesion).

Fractures involving the distal tibia constitute about 11% of all epiphyseal injuries and about 4% of all ankle injuries. The common age of incidence is 11-15 years, with a median age of 14 years in males and 12 years in females. The Tillaux fracture is more common in females, though the majority of ankle injuries generally occur in males.[7, 8] Increased participation in sporting activities for adolescents, particularly those involving pivoting forces, has contributed to increasing incidence since the latter part of the 20th century.

Several series have shown good long-term results with a low incidence of arthrosis (defined as reduction of joint space) after either cast treatment for undisplaced fractures or operative intervention.[9, 10]

Because this fracture occurs in adolescents with a relatively mature growth plate, minimal potential exists for deformity resulting from growth-plate damage. In a systematic review by Tak et al, radiographic deformity was apparent on follow-up only in patients who had received nonoperative treatment of their fracture.[10]

Tillaux fracture is common in adolescents (age 12-15 years) and rare in adults. A history of low-velocity trauma or sporting activities with external rotation of the foot in relation to the leg is common.

Symptoms include the following:

• Severe pain over the anterior aspect of the ankle
• Inability to bear weight
• Limp (in cases of neglected injuries presenting late)

Signs of Tillaux fracture include the following:

• Swelling over the anterior aspect of the distal leg and ankle
• Presence of bruising or ecchymosis
• Possible external rotation deformity of the foot in severe injuries
• Possible tenderness over the region of the medial malleolus or the deltoid ligament if there is failure of the medial column

The lateral aspect of the leg and the entire fibula must be palpated for tenderness to exclude a high fibular fracture. Distal neurovascular status of the limb must be assessed and usually is normal. Checking for instability of the anterior tibiofibular ligament is difficult in the acute setting and must be attempted only with the patient under general anesthesia in the operating room.

Complications due to the injury itself include the following:

• Pain or stiffness for up to 2 years after the injury
• Joint incongruity causing degenerative arthritis
• Varus deformity
• Rotational deformity (rare)
• Tibiotalar slant
• Nonunion
• Delayed union (rare)
• Leg-length inequality (extremely rare)

Plain radiographs of the distal leg and ankle in three planes are recommended, including anteroposterior (AP), lateral, and oblique views.[11] (See the image below.) Frequently, it is difficult to diagnose this injury on AP and lateral views alone, especially when the fragment is only minimally displaced. An oblique view is most helpful for excluding triplane fractures. A mortise view can help to demonstrate widening of the syndesmosis. Note any soft-tissue swelling seen on radiographs.

Radiograph showing avulsion fracture of anterolateral tibia with widening of ankle mortise; fractured fragment appears radiopaque over distal fibula. Also note fracture of talus in this case.

The triplane fracture appears as a Salter-Harris type III fracture on AP radiographs and as a Salter-Harris type II fracture on lateral radiographs, whereas the juvenile Tillaux fracture appears as a Salter-Harris III on both AP and lateral radiographs. Radiographs of the entire tibia and fibula are recommended to exclude high fibular fractures.

Computed tomography (CT) with three-dimensional (3D) reconstruction (3D-CT) is far more accurate than plain radiography in estimating the degree of joint displacement and fracture separation[12] ; accordingly, it must always be performed in this setting, with a high index of suspicion for these injuries. Tomography was used in the past but now has largely been replaced by CT.

Notably, a 2012 study by Liporace et al found that interobserver and intraobserver agreements regarding primary treatment plans did not differ significantly between radiography alone and radiography plus CT.[13] That is, the addition of CT did not significantly change the impression of the amount of displacement per case. In fact, by considering CT, more patients who were assigned nonoperative management initially were reassigned to operative treatment. These findings suggested that CT, though it may influence the decision whether to operate on Tillaux and triplane fractures, may not be as useful as previously thought.

A subsequent study by Szymański et al, however, found that a high percentage (~40%) of malleolar fractures were missed when evaluated with radiography alone and that Tillaux fractures were among the injuries most commonly overlooked in this setting.[14]

Fluoroscopy performed while the foot is rotated internally also is helpful in the assessment of reduction.

Examination under anesthesia is invaluable for ruling out rotatory instability. However, it is seldom necessary if the fracture is already known to be displaced.

Indications for surgical management of a Tillaux fracture include the following:

• Restoration of the articular surface and congruity of the ankle mortise
• Fragment displacement exceeding 2 mm ^{[15, 16]}
• Avoidance of premature closure of the epiphyseal plate

Late presentation is a relative contraindication for forcible manipulation or open reduction to attempt anatomic fixation, because this may lead to further epiphyseal damage.

Arthroscopically assisted reduction and fixation of adult as well as juvenile Tillaux fracture has shown good results and is a promising procedure.[17, 18, 19, 20, 21]

Acute management of the injury consists of splinting, ice packs, compression, and elevation of the involved extremity. Suitable nonsteroidal anti-inflammatory drugs (NSAIDs) must be prescribed. The majority of fractures are minimally displaced, so that no reduction is required and immobilization in a nonweightbearing below-knee cast is sufficient.[22] Epiphyseal separation must be reduced immediately because delay makes it progressively more difficult to achieve closed reduction.

Every fracture requiring reduction is assessed under anesthesia for rotatory instability. All reductions are performed with the utmost gentleness to avoid further damage to the physis.

The fracture is reduced by applying longitudinal traction with the knee flexed at right angles and, while traction is maintained, medially rotating the foot on the leg. Manderson et al suggested that anatomic reduction is achieved and better maintained by maximum dorsiflexion of the ankle during the internal rotation maneuver.[23] The extremity is immobilized for 6-8 weeks in an above-knee cast with the knee flexed to about 30-45° to avoid weightbearing.

Minimally displaced fractures (< 2 mm of displacement) and extra-articular fractures can be treated with immobilization in an above-knee cast, with satisfactory outcomes well documented in the literature.[24]

When 2-3 mm of displacement is present, closed reduction is ideally required under general anesthesia. With the foot in plantarflexion, reduction is achieved with traction and internal rotation. The only exception is with medial fractures in which external rotation facilitates reduction.

Fractures managed conservatively must undergo postreduction computed tomography (CT) to assess the reduction and serial radiography to confirm maintenance of reduction and to follow the progression of physeal closure. If the fragments are displaced more than 2 mm and an acceptable reduction cannot be achieved, surgery is necessary.[25] If the injury presents late, it is better to accept malunion than to cause damage to the epiphysis by forcible manipulation or open surgery.

Evidence from one case series indicated that arthroscopically assisted percutaneous fixation of intra-articular juvenile epiphyseal ankle fractures offers an effective and less invasive form of surgical treatment.[17] This technique has a high learning curve and is technically complex and demanding.

Operative details

Before surgery, adequate preoperative starvation status is determined, the limb is marked, and an informed consent form is obtained from the parents or the older child, explaining the potential sequelae and complications.

The fragment is explored through an anterolateral approach. The incision begins 5 cm proximal to the ankle joint and 2 cm anterior to the anterior border of the fibula; it crosses the ankle about 2 cm medial to the tip of the lateral malleolus and is extended as far distally as required. The internervous plane lies between the peroneal muscles (superficial peroneal nerve) and extensors (deep peroneal nerve).

The extensor tendons, deep peroneal nerve, and dorsalis pedis artery are retracted medially. The ankle capsule is opened, the anterior tibiofibular ligament is identified, and the fracture of the anterolateral portion of the tibial plafond is visualized. The fragment is reduced, with great care taken to avoid damage to the physeal plate.

Smooth Kirschner wires (K-wires), pins, or screws are used, preferably parallel to the ankle mortise, avoiding the epiphysis.[26] A transepiphyseal fixation may be required in very unstable fractures or when reduction cannot be satisfactorily maintained; clinical and functional outcomes appear to be comparable to those of all-epiphyseal fixation.[27]

Feng et al retrospectively evaluated an "all-inside" approach to Tillaux-Chaput fractures in 19 patients (12 male, 7 female; mean age, 28.1 years [range, 10-55]), in which anterolateral and anteromedial ankle arthroscopy was used for closed reduction and internal fixation with one or two Herbert screws.[28]  At the last follow-up, patients had no restrictions in ankle function or range of motion (ROM) and no ankle or walking pain. The American Orthopaedic Foot and Ankle Society (AOFAS) score rose from 52.8 points to 91.7, with an excellent/good rate of 100%.

Postoperative managment includes the following measures:

• Apply a well-padded compression dressing and a posterior splint
• Obtain postoperative radiographs
• Apply an above-knee plaster cast after 48 hours, with the knee flexed and the ankle in neutral position
• Recommend complete nonweightbearing crutch ambulation
• Remove metalwork when the fracture has healed

A long leg cast is recommended in children in spite of internal fixation. The long leg cast can be changed to a below-knee cast after 3-4 weeks. Pins or smooth K-wires are used in young patients, whereas screws are reserved for older, heavier children. In children, metalwork is always removed so that it is not a stress riser in later years.

As in any surgical procedure, multiple opinions exist, but long or short casts, removal of metalwork, and other aspects are always based on the individual surgeon's preference and teaching. The recommendations of this article are based on several leading pediatric orthopedic surgical books that outline the above management as the safest and most reliable.

Routine follow-up after union of the fractured fragment frequently is unnecessary.

Damage to the physis from forceful manipulation may lead to some of the same complications that are associated with the original injury (see Presentation, Complications).

Complications due to surgical treatment include the following:

• Physeal damage by direct pressure on the physis by blunt instruments
• Damage to the superficial peroneal nerve or branches
• Avascular necrosis of the fragment
• Arthrofibrosis following arthroscopic procedures
• Unexplained pain that may persist for up to 12 months after surgery, particularly arthroscopic surgery; many of these cases are probably a result of articular cartilage scuffing/damage