Peter L. Lane, MD, FRCPC

INJURY BIOMECHANICS

Why bother ?

The science of stopping

Some examples of different mechanics and the injuries they produce

How we can learn more

INJURY BIOMECHANICSINTRODUCTION

Accidents will happen

People will get hurt

We'll try to fix them

WHY BOTHER ?

Sudden event

Unpredictable

Unavoidable

"ACCIDENT"

AIDS/TB analogy

Relative importance as a public health issue

Framework of analysis

INJURY AS A DISEASE

Patterns of injury

Predictive of severity and outcome

Prevention/injury control

CLINICAL RELEVANCE

Speed doesn't kill stopping does

dv/dt =

THE SCIENCEOF STOPPING

V

time (msec)

velocity

dV/dT

time (msec)

velocity

dV/dT

V = 15 g

time (msec)

velocity

dV/dT

V = 100 g

Vehicle with barrier

bony structures with vehicle interior

viscera with bony structures

THE 3 COLLISIONS

Environmental factors median barriers roadside obstacles traffic flow

Vehicle factors windshields "friendly" interior steering column

Restraint systems 3 point belts air bags

SLOWING THE STOP

CONTACTS

windshield

steering wheel

dash board

pedals, firewall

INJURIES

facebrainneck

bony thoraxlungs, heart, great vesselsabdominal viscera

knee, femur, hip, pelvis

foot, ankle

CRASH TYPE - FRONTAL

CONTACTS

window/pillar

door panel/intrusion

INJURIES

facebrainneck

bony thoraxlungshippelvis

CRASH TYPE - SIDE

CONTACTS

head rest up

head rest down

seat back

shoulder belt on

INJURIES

scalp contusions

usually soft tissuestrain to neck

none

chest contusionflexion/rotationinj to C- spine

CRASH TYPE - REAR

CONTACTS

shoulder component

lap component

lap belt alone

INJURIES

claviclebony thoraxneck - flexion/rotation

abdominal wallsolid and hollowviscera - compressive

above plusdistraction L - spine

CRASH TYPE - FRONTALBELTS ON

Rollover

Ejection

Motor cycle

Bicycle

Pedestrian

OTHER CRASH TYPES

Why bother ?

The science of stopping

Some examples of different mechanics and the injuries they produce

How we can learn more

INJURY BIOMECHANICSSUMMARY

Crash investigation

Correlation with trauma registry data

Collision data project

Vehicle changes

Road design

Clinical data

Mechanics of other causes

MORE TO BE LEARNED