Peggers’ Super Summary of External Fixation & DCO
Indications:
PATIENT FACTORS
Organ Injury

Thoracic trauma

Polytrauma

HI or raised ICP
Hamodynamic instability

Systolic Bp <100mmhg

Use of catecholamines

Anuria

Transfusion > 25 units of blood
Terrible Traid

Acidosis

Hypothermia

Coagulopathy
Bloods

IL 6 > 800pg/dl

Lactate levels >2.5
All Increase
MOD/MOF
FRACTURE FACTORS

Limb deformity not reduced by non operative techniques
out of hours

Limb shortening or skin compromise due to tenting

Soft tissue damage or skin blisters

Complicated Comminuted intra-articular fracture
Deciding ETC vs DCO:

Stable - ETC

Boarderline - ?? Factors aiding choice include
o ISS > 40
o ISS > 20 + thoracic trauma
o pH < 7.24
o Temperature <350
o Transfusion > 10 RBC
o Coagulopathy
o IL-6

Unstable - DCO

Extremis - DCO
Biomechanics

Monolateral fixation and 60-70% of load is supported by
near cortex

Bending rigidity is ∞ pin diameter 4

2 screws per segment (adding a 3rd makes no difference)

Decrease ‘working length’ of the screws i.e. bone to bar
distance

Near to fracture site screws far away from each other i.e.
shorten working length of bar

Add more bars increases stability

Increase planes increases stability
Preoperative planning

Pin diameter should not exceed 20% of bone diameter

Safe corridors

Spanning or non-spanning of joints
Anatomy Safe Corridors:
NB Avoid 2-3 cm around joints to avoid synovium thus intraarticular joint penetration
PELVIS

ASIS horizontal stab incisions down to bone
o Lateral cutaneous femoral nerve
o Hip joint

Supra-acetabular pin placement
o Risk of injuring femoral vessels
o Lateral femoral cutaneous nerve
o Sciatic notch
o Hip joint
FEMUR

Anterior to 900 laterally
TIBIA

Subcutaneous boarder anteromedially to the tibial spine
running perpendicularly to subcutaneous boarder of the
tibia.

The more distally placed schanz pin needs to be more
medially in a 900 arc
FOOT

2.5cm proximal and anterior to calcaneum through and
through

Medial and in the centre of great toe (1st) MT via open
placement
HUMERUS

Proximal 1/2 blind pin placement into lateral humerus

Distal ½ Open placement laterally to avoid radial nerve
FOREARM

Proximal half subcutaneous ulnar posteriorly

Distal 1/2 Into Radius via open placement between
ECRL/B interval
o To Avoid superficial radial nerve

Dorsal hand pins are inserted either side of listers
tubercle or EPL (4rd compartment) via open placement
HAND

Index Metacarpal 450 to the long axis dorsal radial angle
via open placement distal to the interosseous muscle in
proximal 2/3rds of the MC bone - Avoid radial artery and
superficial radial nerve aim in the middle to avoid
extensor hood or joint
External fixation principles:

Near-far technique

Open placement in ‘danger’ areas

Single pin clamps

Avoid pins in peri-articular regions

Avoid robs over # site; obscure reduction on x ray

REDUCE FRACTURE DISPLACEMENT
Pelvic Fractures:
INDIACATIONS OF PELVIC FRACTURE

Seeing bruising to thighs, flanks or blood at meatus

Movement on pelvic springing
CLASSIFICATION –
1) Burgess & Young

AP Compression – partially stable
o Pubic Diastasis gap >1cm
o >2.5cm = SIJ thus posterior injury

Lateral Compression – partially stable

Vertical Shear - unstable

Combination
Page 1 of 2
Peggers’ Super Summary of External Fixation & DCO
2)
J Orthopaedic Sugery (Am) 1996

Type A – stable

Type B – Partially stable

Type C – Unstable (LC III, APC III, VS)
Algorithm for pelvic Fracture:
MANAGEMENT

75% have massive haemorrhage

25% have urological injuries

20% have abdominal injuries
HAEMORHAGE SOURCE:

Arterial
o Gluteal
o Lateral sacral
o Obturator
o pudendal

Venous
o Posterior venous plexus

# cancellous bone
NB indications for EX-FIX is uncontrolled haemorrhage and
unstable pelvis
ATLS
Closed Pelvis – if in shock
consider another cause
Apply sheet or external
fixator
Arterial bleeding is only present in 10% of cases thus
arteriography is not indicated in UNSTABLE PATIENTS
Katish et al J Trauma 1973
Unstable
Stable
Unstable
Unstable
Treatment
No treatment
Probably not pelvic
– look for other
source
No Urgent pelvic
treatment needed
URGENT pelvic
stabilisation AND
look for other
bleeding sources
Equipment:

Instrument and dissection set

External fixators set
o AO
o Orthofix
o Smith & Nephew

Schanz pins

II + Radiolucent operating table

If unstable pelvis need vascular and general surgeons
DPL / FAST scan negative
DPL / FAST scan POSITIVE
Angiography if available
quickly
External fixator and
laparotomy with packing
Burgess & Young Detailed:
Indication for angiography persisting haemodynamic
instability after pelvic stabilisation without evidence of
abdominal or thoracic haemorrhage
Pelvic Fracture summary:
Mechanical
Haemodynamic
Stable
Stable
Stable
Unstable
Open pelvis
LC
Blood loss in
24hrs*
APC
Blood loss in
24hrs*
VS
Blood loss in
24hrs*
Pubic rami
and sacral #
2.4
Associated iliac
#
2.8
Contralateral
open book
5.7
Anterior
diastasis
ligaments
intact
Isolated anterior
ligament injury
Anterior and
posterior
ligament injury
6.4
20.5
Disruption of
anterior &
posterior
elements
7.8
*Burgess et al J Trauma 1990
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