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1

What are the factors associated with poor outcome in calcaneus fractures

 

age > 60
obesity
manual labor
workers comp
smokers
bilateral calcaneal fxs
vasculopathies
men 

 

2

What are the factors that increase risk of requiring subtalar fusion

Workers comp
Heavy labour
Bohler's <20

3

what is the most frequent tarsal fracture

calcaneus

4

What are the typical radiographic measurements of a calcaneus fracture

  • Bohler angle (normal is 25-40 degrees) 
    • flattening represents collapse of the posterior facet
    • drawn by connecting
      • anterior process
      • highest point on posterior articular surface
      • superior tuberosity
  • Gissane angle (normal is 130-145 degrees)
    • an increase represents collapse of posterior facet
  • Harris view 
    • allows visualization of subtalar joint
    • comminution, degree of varus
    • loss of height, widening, and impingement on peroneal space
    • take with foot maximally dorsiflexed and beam angled at 45 degrees
  • Broden views
    • allows visualization of posterior facet
    • ankle internally rotated 40 degrees and ankle in neutral dorsiflexion. Views taken at 10, 20, 30, 40 degrees
    • largely replaced by CT scan

5

What is the sander's classification of calcaneus fractures

6

What are indications for non-surgical treatment of a calcaenus fracture

Cast immobilization with NWB for 10-12 weeks

Early ROM once swelling decreases, can start partial WB at 6 weeks if going well 

  • extra-articular fx with intact Achilles tendon and < 2mm displacement
  • Sanders Type I (nondisplaced)
  • comorbidities that preclude good surgical outcome (smoker, diabetes, PVD)
  • Worker's compensation (poorer outcomes)

7

What are options of surgical fixation of calcaneus fractures

  • Goals of surgery
    • Return to function
    • Heel width/height
      • Can cause irritation on the peroneals
    • Ability to fit into shoe

  • CRPP
    • in tongue-type fxs or those with mild shortening
  • ORIF after 5-10 days (when swelling gone)
    • indications
      • extra-articular fx with detachment of Achilles tendon and/or > 2mm displacement
      • Sanders Type II and III
    • techniques
      • no benefit to early surgery due to significant soft tissue swelling 
      • wait until swelling/blisters resolves and wrinkle sign present (10-14 days )
      • Nothing to show that you need to use bone graft
      • Nothing to show that you need to lock it…nonunion rates are low
  • primary subtalar arthrodesis
    • indicated in Sanders Type IV
    • technique
      • combined with ORIF to restore height
      • keep in mind that you can't get compression across the joint

8

What are the common complications with calcaneus ORIF?

  • Wound complications (10-25%) 
    • increased risk in smokers, diabetics, and open injuries
    • Keep hardware away from the corner of the incision
    • Initial treatment
      • Wound care, antibiotics, debridement as needed
    • Deep infect without union
      • Requires hardware removal
  • Subtalar post-traumatic arthritis 
    • 5% of patients post-op will require subtalar fusion
    • 20% of patients non-op will reqire subtalar fusion
    • Can try orthotics, supportive footware and cortisone injections first
  • Compartment syndrome (10%)
    • results in clawing of the toes 
    • insensate foot, chronic pain syndrome

9

What deformity can you get with calcaneal malunion?

  • Heel widening
  • Loss of height
  • Calcaneocuboid impingement
  • Varus Heel
  • Post-traumatic Arthrosis

 

10

What is the classification system for calcaneus malunion

Stevenson and saunders

  • A, Type I malunion demonstrating a large lateral wall exostosis, no malalignment, and little or no subtalar arthrosis.
  • B, Type II malunion demonstrating lateral wall exostosis, significant subtalar arthrosis, and varus malalignment ≤10°.
  • C, Type III malunion is similar to type II but with varus malalignment >10°.
  • D, Coronal CT scan demonstrating type III malunion 

 

11

What are associated with subtalar dislocations

  • associated dislocations 
    • talonavicular
    • talocalcaneal
  • associated fractures 
    • with medial dislocation
      • dorsomedial talar head fx
      • posterior tubercles of talus fx
      • navicular fx
    • with lateral dislocation
      • cuboid fx
      • anterior calcaneus fx
      • lateral process of talus fx
      • fibula fx

12

What are the blocks to reduction of a subtalar dislocation

medial dislocation - reduction blocked by

peroneal tendons
extensor digitorum brevis 
talonavicular joint capsule

lateral dislocation - reduction blocked by

posterior tibialis tendon 
flexor hallucis longus
flexor digitorum longus

13

What is the treatment of a subtalar dislocation?

Closed reduction

Open if unable to get closed

Cast/NWB for 4-6 weeks

14

What is the long term risk of OA for subtalar dislocation

ankle joint 89% (31% symptomatic)
subtalar joint 89% (63% symptomatic)
midfoot 72% (15% symptomatic)

15

What is the blood supply to the talus

  • posterior tibial artery
    • via artery of tarsal canal (dominant supply)
    • supplies majority of talar body
  • deltoid branch of posterior tibial artery
    • supplies medial portion of talar body
    • may be only remaining blood supply with a displaced fracture - a posteromedial appraoch would disrupt this, so if you need to, do a med mall osteotomy
  • anterior tibial artery
    • suplies head and neck
  • perforating peroneal arteries via artery of tarsal sinus
    • suplies head and neck

16

What is the best view to assess the talar neck

canale view

  • equinus
  • 15 deg pro
  • 75 deg cephalic tilt of image intensifier
  • Don't forget to also get a CT to assess comminution or other associated foot fractures

17

What is the hawkins classification

  • Hawkins I
    • Nondisplaced
    • 0-13% AVN
  • Hawkins II
    • Subtalar dislocation
    • 20-50%
  • Hawkins III
    • Subtalar and tibiotalar dislocation
    • 20-100%
  • Hawkins IV
    • Subtalar, tibiotalar, and talonavicular dislocation
    • 70-100%

18

What are the approaches and fixation generally used for a talar neck fracture

 

  • can put a bump under the knee to help with flouro
  • anteromedial
    • between tibialis anterior and posterior tibialis
    • preserve soft tissue attachments, especially deltoid 
    • Can use a medial malleolar osteotomy if you need to get access without disrupting the deltoid artery
  • anterolateral
    • between tibia and fibula proximally, in line with 4th ray
    • sharply incise the inferior retinaculum
    • elevate EDB
    • debride sinus tarsi and elevate extensor digitorum brevis - this is important to get your reduction, need an antomical reduction to prevent AVN
  • Fixation
    • provisional anatomic reduction with k-wires
    • two lateral lag screws with a lateral minifrag plate is most common
      • can use a tricortical graft if there is medial comminution
    • retrograde fixation is biomechanicially stronger, but can't get reduction, use posterolateral approach
    • medial plate can help with prevention of varus, but is hard to get access to, need to do osteotomy and keep plate low
  • Post-op
    • ​NWB 10-12 week

19

What is Hawkin's sign

  • subchondarl lucency in the talar dome best seen on AP
  • 6-8 weeks
  • evidence that there is vascularity, good sign
  • Bad sign if you get relative sclerosis

20

What are complications associated with talar neck fractures?

 

  • Osteonecrosis
    • hawkins sign 
      • subchondral lucency best seen on mortise Xray at 6-8 weeks 
      • indicates intact vascularity with resorption of subchondral bone 
    • associated with talar neck comminution and open fractures
  • Posttraumatic arthritis
    • subtalar arthritis (50%) 
      • most common complication 
    • tibiotalar arthritis (33%)
  • Varus malunion (25-30%) 
    • can be prevented by anatomic reduction
    • treatment includes medial opening wedge osteotomy of talar neck 
    • leads to   
      • decreased subtalar eversion
      • decreased motion with locked midfoot and hindfoot
      • weight bearing on the lateral border of the foot

 

21

What is the option for exposure if there is comminution of the talar body

Medial malleolus osteotomy

22

What is your landmark to determine talar neck or talar body

lateral process

23

What is your approach to lateral process fractures

  • Snowboarder's fracture
  • Mechanism
    • dorsiflexion, axial loading, inversion, and external rotation
    • often misdiagnosed as ankle sprain
    • presents as ankle sprain that is not improving after 6 week
  • Imaging
    • Radiographs - may be falsely negative   
    • CT scan 
      • should be performed when suspicion is high (snowboarder) and radiographs are negative
  • Treatment
    • SLC for 6 weeks (NWB first 4 weeks)
      • indicated if nondisplaced (< 2mm)
    • ORIF/Kirshner wires via lateral approach
      • indicated if displaced (> 2mm)
    • Fragment excision
      • indicated if comminuted
      • incompetence of the lateral talocalcaneal ligament is expected with excision of a 1 cm fragment; no ankle or subtalar joint instability is created, however 

24

What is your approach to a posterior process fracture

  • Often confused with os trigonum
  • Radiographs or CT
  • Treatment
    • Nondisplaced (< 2mm)
      • SLC for 6 weeks (NWB first 4 weeks)
    • Displaced (> 2mm)
      • Kirshner wires via posterolateral approach
    • Comminuted
      • excise

25

What is your appraoch to AVN of the talus

  • highly controversial
  • You can usually WB them as soon as you get fracture healing
    • Just because there is AVN doesn't mean you won't get healing
  • Treat symptomatically with pain control
    • explain this may not help with ANV
    • Then follow with serial XR
  • Blair fusion
    • Uses the remaining neck of the talus
  • Others have described filling the void with graft and doing a TTC

26

What is your approach to ARDS

 

  • Causes include
    • trauma
    • shock
    • infection
    • fat emboli
    • thromboembolism
    • multi-system organ failure
  • Presentation
    • tachypmea, dyspnea, hypoxemia
    • decreased lung compliance
  • Labs
    • diagosis after long bone fracture made with ABGs
  • Imaging
    • diffuse infiltrative changes on CXR
  • Treatment
    • ex-fix femur fracture and consult ICU for supportive care until clincial improvement
    • PEEP ventilation and steroids

27

What is your approach to fat emboli syndrome

 

  • Etiology
    • Caused by release of fat and inflammatory mediators from the marrow of long bone fractures
  • Presentation
    • Skin Rash
    • Confusion
    • Respiratory Distress
  • Treatment
    • Fixation of long bone - or stabilizaiton with ex-fix
    • supportive care with positive pressure ventilation in ICU
    • In the acute situation the trauma of the guide wire can make them worse
    • Sometimes it's better to put an ex-fix on, they will do better in the short term ICU stay, but requires another surgery
    • Can consider pelvic Ex-fix for femoral neck fractures 

28

Diagnosis? Classification?

  • AVN of the talus with associated sclerosis (taken 6-8 weeks post-op)
  • Ficat classification

29

Diagnosis?

Lisfranc injury - stress views can help make the diagnosis if the injury is low energy and subtle 

Instability test - just for motion along this joint dorsal and volar, if volar ligaments are still intact and no dorsal dislocation can treat non-op

30

This healthy patient had a fall from height onto a plantar-flexed foot.  What are the key things you need to look for on XR?

five critical radiographic signs that indicate presence of midfoot instability

  1. disruption of the continuity of a line drawn from the medial base of the second metatarsal to the medial side of the middle cuneiform (diagnostic of lisfranc)
  2. widening of the interval between the first and second ray (may see a fleck sign diagnosic of lisfranc)
  3. medial side of the base of the fourth metatarsal does not line up with medial side of cuboid on oblique view
  4. metatarsal base dorsal subluxation on lateral view
  5. disruption of the medial column line (line tangential to the medial aspect of the navicular and the medial cuneiform)

Don't forget WB or stress veiws if you have concerns and there is nothing obvious on XR