Background

Anatomy

 

3 facets

 

1.  Posterior facet (STJ)

2.  Middle facet (sustenaculum tali)

3.  Anterior facet (on distal medial aspect)

 

Anterior process 

- forms calcaneocuboid (CCJ) articulation

 

Thalamic portion 

- under lateral process talus

 

Tuberosities

 

Posterior tuberosity 

- posterior process / T Achilles attachment

 

Medial tuberosity 

- ABDH, FDB, plantar fascia, ADM, Flex Acc

 

Lateral tuberosity

- ADM, long plantar ligament, Flex Acc

 

Aetiology

 

Usually fall from height

- heel in valgus

 

Lateral process talus strikes Crucial Angle Guisanne 

- primary fracture line

- calcaneus driven up against talus

 

MVA

 

Direct blow

 

Essex-Lopresti Classification

 

A.  Extra-Articular  (25%) 

 

Anterior Process fracture

Avulsion of Posterior Tuberosity

Medial & lateral Tuberosity

Sustentaculum Tali

Extra-articular body fractures

 

B.  Intra-Articular (75%) 

 

Epidemiology

- 10% bilateral

- 10% associated with lumbar spine fracture

 

Primary Fracture Line of Palmer

- lateral process of talus driven into crucial angle

- starts at lateral wall near tarsal sinus at crucial angle (in coronal plane)

- passes obliquely across posterior facet

- position of line within the posterior facet variable

- may be medial towards S Tali, middle or lateral towards wall   

- exits at medial wall posterior to sustentaculum tali

 

Produces 2 main fragments

 

1.  Tuberosity / Lateral wall / Variable amount posterior facet

- usually comminuted

- usually displaces superiorly & laterally

 

2.  Sustentaculum / Anterior / Middle facet

- usually undisplaced

 

Sub-classified

- based on appearance of secondary fracture line on lateral X-ray

 

1.  Tongue type (20%)

- secondary fracture line passes posteriorly along calcaneal body to exit laterally below T Ach          

- tuberosity fragment attached to articular fragment (thalamic fragment)

 

Calcaneal Fracture Tongue TypeCalcaneal Fracture Intra-articular

 

2.  Joint Depression (80%)

- secondary fracture line also exits posteriorly

- passes immediately behind the posterior facet of the subtalar joint              

- exits posterior to posterior facet & anterior to T Ach insertion

- creates thalamic portion containing posterior facet

 

Calcaneal Fracture Joint Depression

 

Fracture Anatomy

 

1. Sustenacular Fragment

- constant

- supero-medial 

- attached to talus by deltoid lig

 

2. Superolateral fragment

- thalamic fragment

- lateral fragment of posterior facet

 

3. Lateral wall fragment

 

4. Tuberosity fragment

- posterior heel

 

Examination

 

EMST

 

Lumbar spine

- log roll

- injury in 10%

 

Other heel

- 10% bilateral

 

Foot

- compartment syndrome

 

Effects

- loss heel height

- increased heel width

- varus heel

 

X-ray Views

 

Lateral

- Bohler's angle

- crucial angle Guisane

 

Calcaneal Fracture Lateral

 

Harris axial views

- 45o axial of heel

- normally hindfoot 10o of valgus

- view varus malalignment & heel width

 

Calcaneal Fracture Harris Axial ViewCalcaneal Fracture Harris Axial View

 

Oblique view

- CCJ

 

Calcaneal Fracture Oblique Xray

 

Broden's view

- visualise posterior facet

- IR foot 45 degrees with ankle neutral initially

- plantar flex the foot 10° increments from 10° to 40

- alternatively angle beam cephalad in 10 degree increments

- replaced by CT

- useful intra-op to assess congruency of STJ

 

Xray Angles

 

1.  Bohler's angle  (20-40°)

 

Highest point on anterior process to highest point on posterior facet to highest point on tuberosity

- represents the height of the calcaneus

- angle of </=0° is associated with a poor outcome

 

Indicates

- the posterior facet/ STJ  has collapsed

- proximal displacement of tuberosity

 

Calcaneum Normal Bohlers AngleCalcaneal Fracture Reduced Bohlers Angle

 

2.  Crucial Angle Guisane 120-140°

- lies inferior to lat process of the talus

- where the primary fracture line starts

- disrupted in joint depression fracture

 

Formed by 2 cortical struts

a) lateral border of posterior facet

b) anterior to beak of calcaneus

 

Thus see

- decrease in Bohlers angle

- increase in Gissanes angle 

 

CT scan

 

3 mm cuts

- foot flat on table

- transverse and coronal

- sagittal reconstruction

 

1. Axial

- parallel to bottom of foot

- information regarding CCJ & sustentaculum

 

Calcaneal Fracture Axial CT

 

2. Coronal plane

- perpendicular to posterior facet

- information regarding posterior facet and number of fragments +

- sustentaculum / heel shape / position peroneal & FHL tendons

 

Calcaneal Fracture Coronal CT

 

3.  Sagittal

- Bohlers angle / depression of posterior facet

 

Calcaneal Fracture Lateral CTCalcaneal Fracture Lateral CT

 

Sanders Coronal CT Classification

 

Summary

- calcaneum divided into 3 columns by 2 lines

- based on lateral, central & middle columns of posterior facet

- number of longitudinal fracture lines on coronal CT through post facet

 

Position

- patient positioned supine in scanner with hips & knees flexed 45°

 

Type I 

- undisplaced, irrespective of number of parts

- cast

 

Type II 

- 2 parts of the posterior facet

- > 2mm displacement

- subgroups A,B,C based on primary fracture line

- more medial the fracture line (C), the more difficult to ORIF

 

Calcaneal Fracture Sanders 2

 

Type III 

- 3 part (AB, AC, BC)

- ORIF / fusion

 

Calcaneal Fracture Sanders 3 CT

 

Type IV 

- highly comminuted

- primary fusion