ankle fractures final

$: Ankle fractures final$
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 tibiofibular 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


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 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

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

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

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%

FUNCTION:

Stability- resists external rotation, axial, & lateral displacement of talus

Weight bearing- allows for standard loading

• 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).

ankle fractures final

Education