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PRESENTER: Dr. ANKUR MITTAL
Ankle is a three bone joint composed of the tibia , fibula an talus
Talus articulates with the tibial plafond superiorly , posterior malleolus of the tibia posteriorly and medial malleolus medially
Lateral articulation is with malleolus of fibula
The joint is considered saddle-shaped with the dome itself is wider anteriorly than posteriorly, and as the ankle dorsiflexes, the fibula rotates externally through the tibiofibular syndesmosis, to accommodate this widened anterior surface of the talar dome
The tibiotalar articulation is considered to be highly congruent such that 1 mm talar shift within the mortise decreases the contact area by 42 %
Anterior ColliculusPosterior Colliculus
Intercollicular Groove
Medial malleolus consists of:-Anterior Colliculus-Intercollicular Groove-Posterior Colliculus
Origin: anterior colliculus
Anterior colliculus
Sustantaculm taliNavicular tuberosity
Medial talar tubercle
Medial talusIntercollicular groove
Posterior colliculus
Medial view of fibula
Articular surface
Malleolar fossa
Lateral Ridge
McMinn 1996
Lateral Ligamentous Complex
Chaput tubercle
Wagstaffe tubercle
Volkman tubercle
MEDIAL SIDE LATERAL SIDE
LACINATE LIG.
TARSAL TUNNEL
ANTERIOR SIDE
INTRODUCTION
Ankle fractures are among the most common injuries and management of these fractures depends upon careful identification of the extent of bony injury as well as soft tissue and ligamentous damage.
Once defined, the key to successful outcome following rotational ankle fractures is anatomic restoration and healing of ankle mortise.
IMAGING AND DIAGNOSTIC MODALITIES
OTTAWA ANKLE RULES
To manage the large volume of ankle injuries of patients who presented to emergency certain criteria has been established for requiring ankle radiographs.
Pain exists near one or both of the malleoli PLUS one or more of the following:
•Age > 55 yrs old•Inability to bear weight •Bone tenderness over the posterior edge or tip of either malleolus .
•Plain Films –AP, Mortise, Lateral views of the ankle–Image the entire tibia to knee joint–Foot films when tender to palpation– Common associated fractures are:
•5th metatarsal base fracture•Calcaneal fracture
Although the OTTAWA RULES have been validated and found to be both cost effective and reliable (up to 100% sensitivity their implementation has been inconsistent in general clinical practice
An initial evaluation of the radiograph should 1st focus on
•Tibiotalar articulation and access for fibular shortening
•Widening of joint space
•Malrotation of fibula
•Talar tilt
Identifies fractures of ◦ malleoli◦ distal tibia/fibula◦ plafond◦ talar dome◦ body and lateral
process of talus◦ calcaneous
On the anteroposterior view,
the distal tibia and fibula, including the medial and lateral malleoli, are well demonstrated .
important note is that the fibular (lateral) malleolus is longer than the tibial (medial) malleolus.
This anatomic feature, important for maintaining ankle stability, is crucial for reconstruction of the fractured ankle joint. Even minimal displacement or shortening of the lateral malleolus allows lateral talar shift to occur and may cause incongruity in the ankle joint, possibly leading to posttraumatic arthritis.
Quantitative analysis◦Tibiofibular overlap◦<10mm is abnormal - implies syndesmotic injury◦Tibiofibular clear space ◦>5mm is abnormal - implies syndesmotic injury◦Talar tiltTalar tilt◦>2mm is considered abnormal
Consider a comparison with radiographs of the normal side if there are unresolved concerns of injury
Lateral malleolar fracture
Tib/fib clear space <5mm
Tib/fib overlap >10 mm
No evidence of syndesmotic injury
Taken with ankle in 15-25 degrees of internal rotation
Useful in evaluation of articular surface between talar dome and mortise
10 degrees internal rotation of 5th MT with respect to a vertical line
Medial clear space◦ Between lateral border
of medial malleous and medial talus
◦ <4mm is normal◦ >4mm suggests lateral
shift of talus
•Abnormal findings:–Medial joint space widening–Talocrural angle: <8 or >15 degrees–Tibia/fibula overlap:<1mm
Consider a comparison with radiographs of the normal side if there are unresolved concerns of injury
FIBULAR LENGTH: 1. Shenton’s Line of the ankle2. The dime test
•Posterior mallelolar fractures•AP talar subluxation•Distal fibular translation &/or angulation•Syndesmotic relationship•Associated or occult injuries
–Lateral process talus–Posterior process talus–Anterior process calcaneus
The ankle is a ring◦ Tibial plafond◦ Medial malleolus◦ Deltoid ligaments◦ calcaneous◦ Lateral collateral ligaments◦ Lateral malleolus◦ Syndesmosis
Fracture of single part usually stable
Fracture > 1 part = unstable
Source: Rosen
• Stress Views– Gravity stress view – Manual stress views
• CT– Joint involvement– Posterior malleolar
fracture pattern– Pre-operative planning– Evaluate hindfoot and
midfoot if needed• MRI
– Ligament and tendon injury
– Talar dome lesions– Syndesmosis injuries
Some ligament injuries may be diagnosed on the basis of disruption of the ankle mortise and displacement of the talus; others can be deduced from the appearance of fractured bones.
For example,
fibular fracture above the level of the ankle joint indicates that the distal anterior tibiofibular ligament is torn.
Fracture of the fibula above its anterior tubercle strongly suggests that the tibiofibular syndesmosis is completely disrupted.
Fracture of the fibula above the level of the ankle joint without accompanying fracture of the medial malleolus indicates rupture of the deltoid ligament.
Transverse fracture of the medial malleolus indicates that the deltoid ligament is intact.
High fracture of the fibula associated with a fracture of the medial malleolus or tear of the tibiofibular ligament, the so-called Maisonneuve fracture (see later), indicates rupture of the interosseous membrane up to the level of the fibular fracture
When radiographs of the ankle are normal, however, stress views are extremely important in evaluating ligament injuries .
Inversion (adduction) and anterior-draw stress films are most frequently obtained; only rarely is an eversion (abduction)-stress examination required.
Inversion stress view. (A) For inversion
(adduction)-stress examination of the ankle, the
foot is fixed in the device while the patient is
supine. The pressure plate, positioned
approximately 2 cm above the ankle joint, applies
varus stress adducting the heel. (If the
examination is painful, 5 to 10 mL of 1%
Xylocaine or a similar local anesthetic is injected
at the site of maximum pain.) (B) On the
anteroposterior film, the degree of talar tilt is
measured by the angle formed by lines drawn
along the tibial plafond and the dome of the talus.
The contralateral ankle is subjected to the same
procedure for comparison.
This angle helps diagnose tears of the lateral collateral ligament
The anterior-draw stress film, obtained in the lateral projection, provides a useful measurement for determining injury to the anterior talofibular ligament
Values of up to 5 mm of separation between the talus and the distal tibia are considered normal; values between 5 and 10 mm may be normal or abnormal, and the opposite ankle should be stressed for comparison. Values above 10 mm always indicate abnormality.
Radiography after reduction should be studied with following requirements in mind:
•Normal relationship of ankle mortise must be restored.
•Weight bearing alignment of ankle must be at right angle to the longitudinal axis of leg
•Counters of the articular surface must be as smooth as possible
• Classification systems– Lauge-Hansen– Weber– OTA
• Additional Anatomic Evaluation– Posterior Malleolar Fractures– Syndesmotic Injuries– Common Eponyms
Based on cadaveric study• First word: position of foot at time of injury• Second word: force applied to foot relative to
tibia at time of injury
Types:Supination External RotationSupination AdductionPronation External RotationPronation Abduction
• In each type there are several stages of injury
• Imperfect system:– Not every fracture fits exactly into one category– Even mechanismspecific pattern has been
questioned– Inter and intraobserver variation not ideal– Still useful and widely used
Remember the injury starts on the tight side of the ankle! The lateral side is tight in supination, while the medial side is tight in pronation.
Primary advantage : Characteristic fibular # pattern useful for reconstructing the mechanism of injury a guide for the closed reduction Sequential pattern – inference of ligament injuries
Disadvantages: complicated, variable inter observer reliability doesn’t signify prognosis internal rotation injuries (Weber A3) missed doesn’t indicate stability
1
23
4
Stage 1 Anterior tibio- fibular ligament
Stage 2 Fibula fx
Stage 3 Posterior malleolus fx or posterior tibio-fibular ligament
Stage 4 Deltoid ligament tear or medial malleolus fx
Standard: Closed management
Lateral Injury: classic posterosuperioranteroinferior fibula fracture
Medial Injury: Stability maintained
Lateral Injury: classic posterosuperioranteroinferior fibula fracture
Medial Injury: medial malleolar fracture &*/or deltoid ligament injury
Standard: Surgical management
GOAL: TO EVALUATE DEEP DELTOID [i.e. INSTABILITY]
METHOD: MEDIAL TENDERNESS
MEDIAL SWELLING
MEDIAL ECCHYMOSIS
STRESS VIEWS- GRAVITY OR MANUAL
SER-2
Negative Stress view External rotation of
foot with ankle in neutral flexion (00)
+ Stress View
Widened Medial Clear Space
SE-4SE-4
• Stage 1: fibula fracture is transverse below mortise.
• Stage 2: medial malleolus fracture is classic vertical pattern.1
2
Lateral Injury: transverse fibular fracture at/below level of mortise
Medial injury: vertical shear type medial malleolar fractureBEWARE OF IMPACTION
• Important to restore:– Ankle stability– Articular congruity- including medial
impaction
Stage 1 Deltoid ligament tear or medial malleolus fx
Stage 2 Anterior tibio-fibular ligament and interosseous membrane
Stage 3 Spiral, proximal fibula fracture
Stage 4 Posterior malleolus fx or posterior tibio-fibular ligament
34
1 2
Medial injury: deltoid ligament tear &/or transverse medial malleolar fracture
Lateral Injury: spiral proximal lateral malleolar fracture
HIGHLY UNSTABLE…SYNDESMOTIC INJURY COMMON
• Must x-ray knee to ankle to assess injury
• Syndesmosis is disrupted in most cases– Eponym: Maissoneuve Fracture
• Restore:– Fibular length and rotation– Ankle mortise– Syndesmotic stability
Stage 1 Transverse medial malleolus fx distal to mortise
Stage 2 Posterior malleolus fx or posterior tibio-fibular ligament
Stage 3 Fibula fracture, typically proximal to mortise, often with a butterfly fragment
12 3
Medial injury: tranverse to short oblique medial malleolar fracture
Lateral Injury: comminuted impaction type distal lateral malleolar fracture
• Classification systems– Lauge-Hansen– Weber– OTA
• Additional Anatomic Evaluation– Posterior Malleolar Fractures– Syndesmotic Injuries– Common Eponyms
Based on location of fibula fracture relative to mortise and appearance
Weber A fibula distal to mortise Weber B fibula at level of mortise Weber C fibula proximal to mortise
Concept - the higher the fibula the more severe the injury
SKELETAL TRAUMA
• Classification systems– Lauge-Hansen– Weber– OTA
• Additional Anatomic Evaluation– Posterior Malleolar Fractures– Syndesmotic Injuries– Common Eponyms
Alpha-Numeric Code
Tibia =4
Malleolar segment =4
Infrasyndesmotic=44A
Suprasyndesmotic=44C
Transsyndesmotic=44B
+
AO classification divides the three Danis Weber types further for associated medial injuries.
Alpha-Numeric Code
Infrasyndesmotic=44A
Alpha-Numeric Code
Transsyndesmotic=44B
Alpha-Numeric Code
Suprasyndesmotic=44C
• Classification systems– Lauge-Hansen– Weber– OTA
• Additional Anatomic Evaluation– Posterior Malleolar Fractures– Syndesmotic Injuries– Common Eponyms
Function:Stability- prevents posterior translation of talus &
enhances syndesmotic stability
Weight bearing- increases surface area of ankle joint
• Fracture pattern:– Variable– Difficult to assess on standard lateral
radiograph• External rotation lateral view • CT scan
Type I- posterolateral oblique type Type II- medial extension type
Type III- small shell type
67% 19%
14%
• Classification systems– Lauge-Hansen– Weber– OTA
• Additional Anatomic Evaluation– Posterior Malleolar Fractures– Syndesmotic Injuries– Common Eponyms
FUNCTION:
Stability- resists external rotation, axial, & lateral displacement of talus
Weight bearing- allows for standard loading
• Classification systems– Lauge-Hansen– Weber– OTA
• Additional Anatomic Evaluation– Posterior Malleolar Fractures– Syndesmotic Injuries– Common Eponyms
• Maisonneuve Fracture
– Fracture of proximal fibula with syndesmotic disruption
• Volkmann Fracture
– Fracture of tibial attachment of PITFL
– Posterior malleolar fracture type
• Tillaux-Chaput Fracture
– Fracture of tibial attachment of AITFL
Pott fracture.
In the Pott fracture, the fibula is fractured above the intact distal tibiofibular syndesmosis, the deltoid ligament is ruptured, and the talus is subluxed laterally
Dupuytren fracture. (A) This fracture usually occurs 2 to 7 cm above the distal tibiofibular syndesmosis, with disruption of the medial collateral ligament and, typically, tear of the syndesmosis leading to ankle instability. (B) In the low variant, the fracture occurs more distally and the tibiofibular ligament remains intact.
Wagstaffe-LeFort fracture. In the Wagstaffe-LeFort fracture, seen here schematically on the anteroposterior view, the medial portion of the fibula is avulsed at the insertion of the anterior tibiofibular ligament. The ligament, however, remains intact.
•Collicular Fractures–Avulsion fracture of distal portion of medial malleolus–Injury may continue and rupture the deep deltoid ligament
•Bosworth fracture dislocation
–Fibular fracture with posterior dislocation of proximal fibular segment behind tibia
POSTERIOR COLLICULUS ANTERIOR COLLICULUS
INTERCOLLICULAR GROOVE
Tibial Pilon Fractures
The terms tibial plafond fracture, pilon fracture, and distal tibial explosion fracture all have been used to describe intraarticular fractures of the distal tibia.
These terms encompass a spectrum of skeletal injury ranging from fractures caused by low-energy rotational forces to fractures caused by high-energy axial compression forces arising from motor vehicle accidents or falls from a height.
Rotational variants typically have a more favorable prognosis, whereas high-energy fractures frequently are associated with open wounds or severe, closed, soft-tissue trauma.
Source:Rosen
Rotational fracture of the ankle can be viewed as a continuum, progressing from single malleolar fractures to bimalleolar fractures to fractures involving the distal tibial articular surface.
Lauge-Hansen described a pronation-dorsiflexion injury that produces an oblique medial malleolar fracture, a large anterior lip fracture, a supraarticular fibular fracture, and a posterior tibial fracture.
Giachino and Hammond described a fracture caused by a combination of external rotation, dorsiflexion, and abduction that consisted of an oblique fracture of the medial malleolus and an anterolateral tibial plafond fracture..
These fractures generally have little comminution, no significant metaphyseal involvement, and minimal soft-tissue injury. They can be treated similarly to other ankle fractures with internal fixation of the fibula and lag screw fixation of the distal tibial articular surface through limited surgical approaches
CLASSIFICATION OF ANKLE FRACTURES IN CHILDREN
Salter-Harris anatomic classification as applied to injuries of the distal tibial epiphysis.
Classification of Ankle Fracture in Children (Dias-Tachdjian)
Supination Inversion
grade I adduction or inversion force avulses the distal fibular epiphysis (Salter-Harris type I or II fracture). Occasionally, the fracture is transepiphyseal; rarely, the lateral ligaments fail.
grade II further inversion produces a tibial fracture, usually a Salter-Harris type III or IV and, rarely, a Salter-Harris type I or II injury, or the fracture passes through the medial malleolus below the physis
A.Salter-Harris I fracture of the distal tibia and fibula.
B. B. Salter-Harris I fracture of the fibula, Salter-Harris II tibial fracture.
C.C. Salter-Harris I fibular fracture, Salter-Harris III tibial fracture.
D.D. Salter-Harris I fibular fracture, Salter-Harris IV tibial fracture.
Variants of grade II supination inversion injuries (Dias-Tachdjian classification).
Supination Plantarflexion
The plantarflexion force displaces the epiphysis directly posteriorly, resulting in a Salter-Harris type I or II fracture. Fibular fractures were not reported with this mechanism. The tibial fracture usually is difficult to see on anteroposterior x-rays
Supination External RotationIn grade I the external rotation force results in a Salter-Harris type II fracture of the distal tibia The distal fragment is displaced posteriorly, as in a supination plantarflexion injury, but the Thurston-Holland fragment is visible on an anteroposterior x-ray, with the fracture line extending proximally and medially. Occasionally, the distal tibial epiphysis is rotated but not displaced.
In grade II, with further external rotation, a spiral fracture of the fibula is produced, running from anteroinferior to posterosuperior (
Pronation Eversion External Rotation
A Salter-Harris type I or II fracture of the distal tibia occurs simultaneously with a transverse fibular fracture. The distal tibial fragment is displaced laterally, and the Thurston-Holland fragment, when present, is lateral or posterolateral . Less frequently, a transepiphyseal fracture occurs through the medial malleolus (Salter type II).