Keywords
ankle fractures - ankle injuries - bone screws - tibial fractures
Introduction
Tillaux fractures are avulsion fractures of the anterior-inferior tibiofibular ligament
(AITFL) from its tibial attachment, which typically occur in adolescents nearing skeletal
maturity (12–14-years-old). This fracture pattern has not been commonly seen in an
older population, since the ligaments usually fail before the bone.[1]
The incidence of isolated Tillaux fractures in adults has not been quantified in the
current data, as it has been more commonly seen in association with other injuries.
According to the literature, only 7 case reports have been published regarding this
entity.[2]
The present case-report-based literature review aims to elicit the existing information
regarding isolated Tillaux fractures in adults and provide a summary about its mechanism
of injury, diagnosis, and treatment procedures.
Case Report
A 46-year-old woman was admitted to the emergency department after a domestic ankle
trauma with external rotation mechanism. Physical examination revealed tenderness
and swelling over the anterolateral aspect of the ankle with normal but painful passive
range of motion.
The images of x-ray ([Fig. 1]) and computed tomography (CT) scan ([Fig. 2]) showed an isolated Tillaux fracture with 4 mm of fragments displacement and anterior
disruption of the syndesmosis. Open reduction and fixation were performed with 2 cannulated
4.0 screws, perpendicular to the fracture line by a mini-open anterolateral approach—proximally
centered between the tibia and fibula, and distally extended in line with the fourth
metatarsal in an intermuscular plane between the peroneus brevis and tertius. The
superficial peroneal nerve runs anterior to the fibula and requires identification
in the proximal extent of the incision.[3]
Fig. 1 Preoperative X-ray view: (A) anteroposterior and (B) lateral.
Fig. 2 Preoperative CT scan view: (A) coronal and (B) axial.
Fluoroscopic imaging ([Fig. 3]) was used intraoperatively to confirm fracture reduction, correct positioning of
the screws, and syndesmotic stability with the negative external rotation stress test.
Fig. 3 Intraoperative fluoroscopic imaging view: (A) anteroposterior and (B) lateral.
Postoperatively, a short leg cast was prescribed during 4 weeks for fear of patient's
lack of compliance with the no weight-bearing discharge instructions. Mobilization
started at the 4th week, partial weight-bearing was allowed from the 6th week onwards, and was gradually increased according to clinical and radiological
evidence of union up to full weight-bearing and normal walking.
After 4 months of proper rehabilitation, the patient exhibited an excellent clinical
and functional outcome, scoring 80 in the Karlsson scale. A postoperative control
CT scan ([Fig. 4]) confirmed a successful bone healing.
Fig. 4 Postoperative control CT scan view: (A) coronal and (B) axial.
Discussion
Historically, this fracture pattern has been noted in the adolescent population due
to the pattern of progression of physeal closure and classified as a Salter-Harris
III fracture through the epiphysis.[4]
Ankle syndesmosis is formed by the distal tibia and fibula, and it is stabilized by
four ligaments: the anterior, transverse, and posterior tibiofibular ligaments, as
well as the interosseous membrane.[2]
Supination and external rotation (SER) were identified as the most common mechanism
of injury; leading to avulsion of the anterolateral tibia site of attachment of the
anterior inferior tibiofibular ligament. This mechanism of injury is typically divided
into 4 stages. However, in isolated Tillaux fracture scenarios, the sequence of events
ends at stage 1, since no fibula fracture, posterior osseous injury, or medial involvement
are present.[1] Fall from height is also described as a possible injury mechanism.[2]
Nondisplaced Tillaux fractures are often almost unrecognizable on standard X-ray projections
and may be misdiagnosed as a simple sprain due to its challenging diagnosis. Stress
X-ray imaging and oblique projection should be used as supplemental diagnostictools.[1] Additional CT evaluation is also recommended for determining the distance of displacement,
fracture fragments shape, and conditions of the articular surface.[4]
In adult Tillaux fractures the avulsed fragment is generally triangular, while in
juvenile Tillaux fractures it is quadrangular.[5]
A total of three main types of fractures can be differentiated: (1) extra-articular
avulsion fracture of the AITFL, (2) fracture of the anterolateral distal tibia with
involvement of the articular surface, and (3) impaction fracture of the anterolateral
tibial plafond.[6]
Nondisplaced fractures (< 2 mm) with no evidence of syndesmosis instability can be
managed conservatively by long leg cast with internally rotated foot. Since the strong
anteroinferior ligament is attached to the fibula, it renders the bone displaced and
angulated, causing syndesmotic incompetency. Therefore, a displaced fracture (> 2mm)
is an indication for close or open reduction and internal fixation.[7]
Conservative treatment of dislocated fragments leads to non-union and post-traumatic
osteoarthritis. Impaction fractures can lead to secondary avascular necrosis of the
anterolateral tibial plafond.[6]
The aim of surgical fixation of displaced anterolateral distal tibial fractures is
the anatomical stabilization of the anterior syndesmosis and restoration of the tibial
incisura for the distal fibula and joint surface. A type 1 fracture may be fixed with
an anchor or transosseous suture, type 2 is mostly fixed with screws, and type 3 may
need bone grafting of the impaction zone for restoration of the joint surface and
buttress plating.[6]
It is not yet clear whether the fibula should be temporarily fixed to the tibia but,
irrespective of the type of treatment, fixation for six weeks with instructions not
to load the injured limb is indicated.[2]
Open reduction can be done by anterior or anterolateral approach—it should depend
on the extent of the fracture line. Using the anterolateral approach, a second approach
to address a medial component is often necessary in more severe injuries. On the other
hand, using the anterior approach, the entire anterior portion of the distal tibia
is accessible, but the neurovascular bundle is at higher risk both proximally and
distally.[3]
Percutaneous fixation techniques have also been described to treat this injury, predominantly
among adolescents.[8] Arthroscopically assisted fixation technique has been described but no actual literature
evidence suggests that this method is overall superior to traditional open reduction.[9] It represents a more accurate method with treatment possibility of any associated
intra-articular pathology and lower risk of infection, bleeding, and biological damage
to structures.[1]
As a mainly intra-articular fracture, anatomical reduction, absolute stability, and
early mobilization are the most important factors to ensure a better functional outcome.[10]
Fraturas isoladas de Tillaux em adultos podem ser indicativas de uma lesão sindesmótica
no tornozelo. É importante reconhecer e tratar adequadamente essas lesões distintas
para evitar maiores instabilidades, alterações degenerativas e limitação da função
articular do tornozelo.
Além da rara ocorrência na idade adulta, outra característica dessa fratura é que
ela é desafiadora para detectar, sendo facilmente negligenciada. Um diagnóstico precoce
e a osteossíntese apropriada desempenham um papel significativo em um prognóstico
de recuperação bem-sucedido.
Isolated Tillaux fractures in adults may be indicative of a syndesmotic ankle injury.
It is important to recognize and appropriately treat these distinct injuries to prevent
further instability, degenerative changes, and ankle joint function limitation.
In addition to the rare occurrence in adulthood, another feature of this fracture
is that it is challenging to detect, being easily overlooked. An early diagnosis and
appropriate osteosynthesis play a significant role in a successful recovery prognosis.
