Bony-ankle-injuries

3. • Injury patterns
 Isolated medial malleolus fracture
 Isolated lateral malleolus fracture
 Bimalleolar fracture
 Posterior malleolus fractures
 Bosworth fracture-dislocations
 Open ankle fractures
 Associated/Isolated syndesmosis injuries

4. • Radiographs
 AP, Lateral and Obliques
 External rotation stress radiograph
 Most appropriate stress radiograph to assess competency of
deltoid ligament
 A medial clear space of >5mm with external rotation stress
applied to a dorsiflexed ankle is predictive of deep deltoid
disruption
 More sensitive to injury than medial tenderness, ecchymosis, or
edema

5. • Radiographic measurements
 Talocrural angle
 measured by bisection of line through tibial anatomical axis and
another line through the tips of the malleoli
 shortening of lateral malleoli fractures can lead to increased
talocrural angle
 Talocrural angle is not 100% reliable for estimating restoration of
fibular length

7. • Classification
 Anatomic / Descriptive
 Isolated medial malleolar
 Isolated lateral malleolar
 Bimalleolar
 Trimalleolar
 Bosworth fracture-dislocation
(posterior dislocation of the fibula behind incisura fibularis)

8.  Lauge-Hansen
 Based on foot position and force of applied stress/force
 Shown to predict the observed (via MRI) ligamentous
injury in less than 50% of operatively treated fractures

9. Supination - Adduction
(SAD)
• Talofibular sprain or distal fibular avulsion
• Vertical medial malleolus and impaction of
anteromedial distal tibia

10. Supination external rotation
(SER)
• Anterior tibiofibular ligament sprain
• Lateral short oblique fibula fracture
(anteroinferior to posterosuperior)
• Posterior tibiofibular ligament rupture
or avulsion of posterior malleolus
• Medial malleolus transverse fracture
or disruption of deltoid ligament

11. Pronation external rotation
(PER)
• Medial malleolus transverse fracture or
disruption of deltoid ligament
• Anterior tibiofibular ligament disruption
• Lateral short oblique or spiral fracture of
fibula (anterosuperior to posteroinferior)
above the level of the joint
• Posterior tibiofibular ligament rupture or
avulsion of posterior malleolus

12. Pronation Abduction
(PAB)
• Medial malleolus transverse fracture or disruption
of deltoid ligament
• Anterior tibiofibular ligament sprain
• Transverse comminuted fracture of the fibula
above the level of the syndesmosis

13.  Denis-Weber (location of fibular fracture)
 A - infrasyndesmotic (generally not associated with ankle instability)
 B - transsyndesmotic
 C – suprasyndesmotic

14.  AO classification

15. • General Treatment
 Nonoperative
 Short-leg walking cast/boot
 Isolated nondisplaced medial malleolus fracture or tip avulsions
 Isolated lateral malleolus fracture with < 3mm displacement
and no talar shift
 Posterior malleolar fracture with < 25% joint involvement
or < 2mm step-off

16.  Operative (Open reduction internal fixation)
 Any talar displacement
 Displaced isolated medial malleolar fracture
 Displaced isolated lateral malleolar fracture
 Bimalleolar fracture and bimalleolar-equivalent fracture
 Posterior malleolar fracture with > 25% or > 2mm step-off
 Bosworth fracture-dislocations
 Open fractures
 Goal of treatment
 stable anatomic reduction of talus in the ankle mortise
 1 mm shift of talus leads to 42% decrease in tibiotalar contact area

17.  Outcomes
 overall success rate is high
 prolonged recovery expected (2 years to obtain final functional result)
 significant functional impairment often noted
 worse outcomes with: smoking, decreased education, alcohol use,
increased age, presence of medial malleolar fracture
 ORIF superior to closed treatment of bimalleolar fractures
 In Lauge-Hansen supination-adduction fractures, restoration of marginal
impaction of the anteromedial tibial plafond leads to optimal functional
results after surgery

18. • ISOLATED MEDIAL MALLEOLUS FRACTURE
 Nonoperative (short leg walking cast or cast boot)
 Nondisplaced fracture and tip avulsions
 Operative (ORIF)
 Any displacement or talar shift
 Lag screw fixation (stronger if placed perpendicular to fr line)
 Antiglide plate with lag screw (Best for vertical shear fr)
 Tension band fixation

20. • ISOLATED LATERAL MALLEOLUS FRACTURE
 Nonoperative (short leg walking cast vs cast boot)
 intact mortise
 no talar shift
 < 3mm displacement
 Classically fractures with more than 4-5 mm of medial clear space
widening on stress radiographs have been considered unstable and
need to be treated surgically
 Recent studies have shown the deep deltoid may be intact with up
to 8-10 mm of widening on stress radiographs
 if the mortise is well reduced, results from operative and non-
operative treatment are similar

21.  Operative (ORIF)
 if talar shift or > 3 mm of displacement
 can be treated operatively if also treating an ipsilateral syndesmosis
injury
 Open reduction and plating
 plate placement
 lateral
 lag screw fixation with neutralization plating
 bridge plate technique

22.  posterior
 antiglide technique
 lag screw fixation with neutralization plating
o most common disadvantage of using posterior antiglide plating
is peroneal irritation if the plate is placed too distally
o posterior antiglide plating is biomechanically superior to lateral
plate placement
 intramedullary retrograde screw placement

24.  Post-operative care
 period of immobilization usually 4-6 weeks after ORIF
 duration of immobilization should be doubled in Diabetic patients

25. • MEDIAL AND LATERAL (BIMALLEOLAR) FRACTURE
 Operative (ORIF)
 any lateral talar shift
 Technique:
 Fibula (fixed as previously)
 medial malleolus
 cancellous lag screws
 bicortical screws
 tension band wiring
 antiglide plate to treat a vertical medial malleolus
fracture (screws parallel to joint)

26. • FUNCTIONAL BIMALLEOLAR FRACTURE
(deltoid ligament tear with fibular fracture)
 Operative (ORIF of lateral malleolus)
 can see significant lateral translation of the talus in this pattern
 not necessary to repair medial deltoid ligament
 only need to explore medially if you are unable to reduce the
mortise

28. • POSTERIOR MALLEOLAR FRACTURE
 Nonoperative (short leg walking cast vs boot)
 < 25% of articular surface involved
(CT rather than Xrays “unreliable”)
 < 2 mm articular stepoff
 syndesmotic stability
 Operative (ORIF)
 > 25% of articular surface involved
 > 2 mm articular stepoff
 syndesmosis injury

29.  Approach
 posterolateral approach
 posteromedial approach
 Fixation
 anterior to posterior lag screws to capture fragment (if
nondisplaced)
 posterior to anterior lag screw and buttress plate
 antiglide plate

30.  Syndesmosis injury
 stress examination of syndesmosis still required after posterior
malleolar fixation
 posteroinferior tibiofibular ligament may remain attached to
posterior malleolus and syndesmotic stability may be restored
with isolated posterior malleolar fixation

31. • BOSWORTH FRACTURE-DISLOCATION
 rare fracture-dislocation of the ankle where the fibula becomes
entrapped behind the tibia and becomes irreducible
 posterolateral ridge of the distal tibia hinders reduction of the fibula
 Operative (ORIF of the fibula in the incisura fibularis)
 indicated in most cases

33. • OPEN ANKLE FRACTURE
 Operative
 Emergent operative debridement and ORIF
 indicated if soft tissue conditions allow
 External fixation
 According to soft tissue and overall patient conditions.

34. • ASSOCIATED SYNDESMOTIC INJURY
 suspect injury in all ankle fractures
 most common in Weber C fracture patterns
 up to 25% of tibial shaft fractures will have ankle injury

35.  Evaluation:
 measure clear space 1 cm above joint
 it has also been reported that there is no actual correlation
between syndesmotic injury and tibiofibular clear space or
overlap measurements
 best option is to assess stability intraoperatively with
abduction/external rotation stress of dorsiflexed foot
 instability of the syndesmosis is greatest in the anterior-
posterior direction
 lateral stress radiograph has more interobserver reliability than
an AP/mortise stress film

36.  Treatment (operative: syndesmotic screw fixation)
 widening of medial clear space
 tibiofibular clear space (AP) greater than 5 mm
 tibiofibular overlap (mortise) narrowed
 any postreduction malalignment or widening should be treated with
open debridement, reduction, and fixation

37.  Technique
 length and rotation of fibula must be accurately restored.
 one or two cortical screw(s) 2-4 cm above joint, angled posterior
to anterior 20-30 degrees
 lag technique not desired
 maximum dorsiflexion of ankle not required during screw placement
(can't overtighten a properly reduced syndesmosis)

40.  Postoperative
 screws should be maintained in place for at least 8-12 weeks
 must remain non-weight bearing, as screws are not biomechanically
strong enough to withstand forces of ambulation
 Controversies
 number of screws
o 1 or 2 no difference
 number of cortices
o 3 or 4 no difference
 size of screws
o 3.5 mm or 4.5 mm screws
 implant material
o (stainless steel screws, titanium screws, suture, bioabsorbable
materials)
 need for hardware removal
o no difference in outcomes seen with hardware maintenance
(breakage or loosening) or removal at 1 year

41. • Complications
 Wound problems (4-5%)
 Deep infections (1-2%)
 up to 20% in diabetic patients
 largest risk factor for diabetic patients is presence of peripheral
neuropathy
 Post-traumatic arthritis
 rare with anatomic reduction and fixation