lecture 9 shah ankle fractures

Download Lecture 9 shah ankle fractures

Post on 11-Jan-2017

603 views

Category:

Documents

4 download

Embed Size (px)

TRANSCRIPT

Ankle fractures: controversies, syndesmosis & posterior malleolus

Ankle fractures: controversies, syndesmosis & posterior malleolusDr.Rajiv ShahFoot & Ankle OrthopaedicsFoot & 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 surgeryLate presentations & poor skin conditionWait up to 7 daysJoint spanning ex-fixWrinkle sign

No recent dataEarly surgery prevents blister formation!If present, waitAvoid incising through blisters

Literature?Blisters

Concerns: PID & DMIncreased 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 swellingMedial tendernessMedial ecchymosisIf ve then stable lateral malleolar fractureRecent Literature

Stable v/s unstable lat.malleous # Old Literature

Medial examination - poor predictor

Manual stress testGravity stress testTrial of weight bearing & reanalysis

Restoration of fibular length Medial exploration /FixationPost malleolar fixation Assessment of mortise stabilitySyndesmotic fixation

Fixation chronologyNot 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 > 2mmPersistent subluxation of joint

Recent Literature

Posterior malleolus # Old Literature

Every posterior malleolar fracture should be fixed!Forms part of incisuraVery 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 fracturesIf 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

HistoryPain & swellingEcchymosisTenderness at syndesmosis

Clinical diagnosisSpecial tests Squeeze testExternal 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 standard

CT definition of anatomic syndesmosis?

Surest CT sign = Tibiotalar lineLine 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 TIBIA

MRI

Syndesmotic ligament injuryAssociated injuries Talar dome OCD -28% Bone bruise -24% ATFL -74%

Hook test-pull fibula laterally & take image

Five testsIntra-operative diagnosis

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

Tap test push tap forward in syndesmosis & see widening

Modified cottons 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 tibia25-30 degree PL to AM2 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 fixation3.5mm more likely to break (Panchbari et al)Avoid cannulated screwsLarger 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 symptomatic4 cortices are more likely to break as they are more stiffer

3 cortices or 4 cortices?

Controversies: syndesmotic screw

No consensusTwo screws better on mechanical studiesTwo screws better stability to torsional stress Stability is better with a screw through the plateStiff construct eliminates even more normal motion

Single or double screw?

Controversies: syndesmotic screw

2.5 cm above ankleLess than 2 cm = chances of synostosisMore 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 resultsBio-absorbable early return to workBio-absorbable FB reaction, wear, osteolysis, ? Joint damage

SS , Titanium or bio-absorbable?

Controversies: syndesmotic screw

Allows natural movement of ankleLess likely to give malreductionNo need for removalNo difference b/w tightrope and screws in biomechanics (cadaveric studies)

Screw orTight rope?

Controversies: syndesmotic screw

Supposed to be biomechanically betterSome do require re operation (irritation due to knot)/ suffer from osteolysis and sinkageHave shown improved functional outcomes and early recovery

Screw or Tight rope?

Controversies: syndesmotic screw

No difference between outcome in fractures, loosened or removed screwsTibiofibular space narrower in intact screw groupScrew removal advised for intact screws

Remove or retain?

Controversies: syndesmotic screw

Better AOFAS score when screw breaks or is removedWalking prior to removal of screws does not affect outcomeMajority screw breaks

Remove or retain?

Controversies: syndesmotic screw

Tibiofibular space narrower in intact screw groupIncreased ROM after screw removalScrew removal advised for intact screwsAt 3 months follow up if ankle dorsiflexion is not improving then screw removal

Remove or retain?

Controversies: syndesmotic screw

25%-50% malreduction80% reduced after screw removalUse of tight rope?Intra-op direct visualization reduced rate of malreduction from 44% to 15%!Intra-op CTPost op CT

How to prevent malreduction?Tibio fibular synostosisReduced external rotation

How to salvage failed syndesmosis ?

Current Practice in USA3.5mm screws51%4.5mm screws24%Suture device14%1 screw44%2 screws44%3 cortices 29%4 cortices 67%

Routine removal65% (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 reductionDifficult fibula reductionDifficult to maintain fibula reduction Medial explorationInterposition of deltoid, post tib tendon, osteochondral fragmentsRoutine repair of deltoid is controversial except rupture with bony fragment or with association with extensive soft tissue damageWhen?

Medial side exploration

Wound healingDeep infectionImplant looseningLoss of fixation

Problems

Fractures in elderlySolutions

Posterior antiglide plateBicortical screwsFibula pro tibia screws+ ex fixHook plateIM fixation of fibulaIM k wires + plateLCPBone cement augmentationBone substitutesMedical management

Poor radiological outcomeDeep infectionRevision ratesLoss of fixation & conversion in charcot

Problems

Fractures in diabeticsSolutions

Medical managementTwo types of surgical guidelines

Thats allThank you all..