lecture 9 shah ankle fractures

Ankle fractures: controversies, syndesmosis & posterior malleolus

Dr.Rajiv Shah‘Foot & Ankle Orthopaedics’Foot & Ankle SurgeonPresident, Indian Foot & Ankle Society

Ankle fractures are surrounded by many controversies!!

Ankle fractures are not that simple as we think!

Early surgery(within first 24 hours) is with better outcome!

Recent literature

Timing of surgery

Late presentations & poor skin condition…

Wait up to 7 days

Joint spanning ex-fix

‘Wrinkle sign’

No recent data Early surgery

prevents blister formation!

If present, wait Avoid incising

through blisters

Literature?

Blisters

Concerns: PID & DM Increased post-op pain +

swelling Early ROM is achieved if

tourniquet is not used! (Konrad G et al – CORR, 2005 )

Recent Literature

Use of tourniquet

Medial swelling Medial tenderness Medial ecchymosis If –ve then stable

lateral malleolar fracture

Recent Literature

Stable v/s unstable lat.malleous # Old Literature

Medial examination - poor predictor

Manual stress test Gravity stress test Trial of weight

bearing & reanalysis

Restoration of fibular length Medial exploration /Fixation Post malleolar fixation Assessment of mortise

stability Syndesmotic fixation

Fixation chronology

Not hard & fast!Achieving fibular length & syndesmotic stability are more important!!

If fibula is comminuted, medial side may be reduced first

Fix if posterior malleolus #

>then 25% Articular step of >

2mm Persistent

subluxation of joint

Recent Literature

Posterior malleolus # Old Literature

Every posterior malleolar fracture should be fixed!

Forms part of incisura

Very important for syndesmotic stability

Gardner (2006) demonstrated that posterior malleolar fixation restored 70% of syndesmosis stability compared with 40% after syndesmotic screw insertion!

Routine X-rays have got poor diagnostic value! External rotation lateral view, a must!CT Scan – gold standard

Posterior malleolus # Attachment of strong PITFL makes it mandatory to fix posterior malleolus fracture

Not the size of fragment but the stability of ankle is more significant!

Fix them posterior to anterior between peronei and FHL!

Occurs in 23% of ankle fractures

If deltoid is also injured then there is marked instability

Anatomical reduction is a must!

Syndesmosis injury

Anterior inferior tibio-fibular ligament

Posterior inferior tibio-fibular ligament

Interosseous ligament

Medial ligaments

History Pain &

swelling Ecchymosis Tenderness at

syndesmosis

Clinical diagnosisSpecial tests

Squeeze test

External rotation stress test

Dorsiflexion of ankle + syndesmosis squeeze or tapping relieves pain

Radiological diagnosisX-raysStress viewsCT Scan

Increased Tibio-fibular clear space Tibio- fibular overlap

Increased medial Clear Space Disturbed Talocrural angle

Lateral talar shift sign

Ankle instability sign

Larger medial clear space than superior clear (ankle joint) space

Gravity stress test CT Scan – Gold standardCT definition of anatomic syndesmosis?Surest CT sign = Tibiotalar line

Line from AL fibula to ant.tubercle of tibia, 1 cm above plafond on axial CT cutMUST BE WITH IN TWO MM FROM ANTERIOR SURFACE OF TIBIAMRI

Syndesmotic ligament injury Associated injuries – Talar dome OCD -28% Bone bruise -24% ATFL -74%

Hook test-pull fibula laterally & take image

Five tests

Intra-operative diagnosis

External rotation test – hold leg & rotate foot externally & take AP image

Tap test – push tap forward in syndesmosis & see widening

Modified cotton’s test – pull fibula posteriorly & take LAT image

Ballottement test – rock/slide fibula anteroposteriorly

Arthroscopy has increasing role in diagnosis!Open & make sure!Fragment in syndesmosis = open

Fibula to tibia 25-30 degree

PL to AM 2 cm above &

parallel to joint line

Screw

Syndesmotic fixation

• No mechanical advantage of 4.5 mm over 3.5 mm in tricortical fixation • 4.5 mm superior mechanically in quadricortical fixation• 3.5mm more likely to break (Panchbari et al)• Avoid cannulated screws• Larger diameter screws provide great resistance to shear forces

3.5mm or 4.5 mm?

Controversies: syndesmotic screw

No difference in outcomes between tri-cortical or quadri-cortical but QC can be removed easily if break and symptomatic

4 cortices are more likely to break as they are more stiffer

3 cortices or 4 cortices?

Controversies: syndesmotic screw

▪ No consensus▪ Two screws better on mechanical studies▪ Two screws better stability to torsional stress ▪ Stability is better with a screw through the plate▪ Stiff construct eliminates even more normal

motion

Single or double screw?

Controversies: syndesmotic screw

2.5 cm above ankle Less than 2 cm = chances of

synostosis More than 5cm = widening of

syndesmosis on external rotation

Where ?

Controversies: syndesmotic screw

Over tightening of syndesmosis is possible?!

Position of ankle in dorsiflexion during screw fixation does not matter but anatomic reduction does matter a great!

Position of ankle?

Controversies: syndesmotic screw

Every material steel, titanium or bio-absorbable showed similar results

Bio-absorbable – early return to work Bio-absorbable – FB reaction, wear,

osteolysis, ? Joint damage

SS , Titanium or bio-absorbable?

Controversies: syndesmotic screw

Allows natural movement of ankle Less likely to give malreduction No need for removal No difference b/w tightrope and screws

in biomechanics (cadaveric studies)

Screw orTight rope?

Controversies: syndesmotic screw

Supposed to be biomechanically better Some do require re operation (irritation

due to knot)/ suffer from osteolysis and sinkage

Have shown improved functional outcomes and early recovery

Screw or Tight rope?

Controversies: syndesmotic screw

No difference between outcome in fractures, loosened or removed screws

Tibiofibular space narrower in intact screw group

Screw removal advised for intact screws

Remove or retain?

Controversies: syndesmotic screw

Better AOFAS score when screw breaks or is removed

Walking prior to removal of screws does not affect outcome

Majority screw breaks

Remove or retain?

Controversies: syndesmotic screw

Tibiofibular space narrower in intact screw group

Increased ROM after screw removal Screw removal advised for intact screws ‘At 3 months follow up if ankle dorsiflexion

is not improving then screw removal’

Remove or retain?

Controversies: syndesmotic screw

25%-50% malreduction 80% reduced after screw removal Use of tight rope? Intra-op direct visualization reduced rate

of malreduction from 44% to 15%! Intra-op CT Post op CT

How to prevent malreduction?

Tibio fibular synostosis Reduced external rotation

How to salvage failed syndesmosis ?

Current Practice in USA

• 3.5mm screws 51%• 4.5mm screws 24%• Suture device 14%• 1 screw 44%• 2 screws 44%• 3 cortices 29%• 4 cortices 67%

• Routine removal 65% (95% OR)(3 months 49%, 4 months 37%, 6months 12%)

•Most common practice: 3.5 mm screw, 4 cortices routinely removed in OR at 3 months

Wide medial clear space after fibula reduction Difficult fibula reduction Difficult to maintain fibula reduction Medial exploration Interposition of deltoid, post tib tendon,

osteochondral fragments Routine repair of deltoid is controversial except

rupture with bony fragment or with association with extensive soft tissue damage

When?

Medial side exploration

Wound healing Deep infection Implant

loosening Loss of fixation

Problems

Fractures in elderlySolutions

Posterior antiglide plate Bicortical screws Fibula pro tibia screws + ex fix Hook plate IM fixation of fibula IM k wires + plate LCP Bone cement

augmentation Bone substitutes Medical management

Poor radiological outcome

Deep infection Revision rates Loss of fixation

& conversion in charcot

Problems

Fractures in diabeticsSolutions

Medical management

Two types of surgical guidelines

That’s all…Thank you all..