INJURY BIOMECHANICS Peter L Lane MD FRCPC INJURY

INJURY BIOMECHANICS Peter L. Lane, MD, FRCPC

INJURY BIOMECHANICS INTRODUCTION l Why bother ? l The science of stopping l Some examples of different mechanics and the injuries they produce l How we can learn more

WHY BOTHER ? l Accidents will happen l People will get hurt l We'll try to fix them

"ACCIDENT" l Sudden event l Unpredictable l Unavoidable

INJURY AS A DISEASE l AIDS/TB analogy l Relative importance as a public health issue l Framework of analysis

CLINICAL RELEVANCE l Patterns of injury l Predictive of severity and outcome l Prevention/injury control

THE SCIENCE OF STOPPING l l Speed doesn't kill stopping does dv/dt = V

d. V/d. T v e l o c i t y time (msec)

d. V/d. T v e l o c i t y V = 15 g time (msec)

d. V/d. T v e l o c i t y V = 100 g time (msec)

THE 3 COLLISIONS l Vehicle with barrier l bony structures with vehicle interior l viscera with bony structures

SLOWING THE STOP l Environmental factors median barriers roadside obstacles traffic flow l Vehicle factors windshields "friendly" interior steering column l Restraint systems 3 point belts air bags

CRASH TYPE - FRONTAL CONTACTS INJURIES windshield face brain neck steering wheel dash board bony thorax lungs, heart, great vessels abdominal viscera pedals, firewall knee, femur, hip, pelvis foot, ankle

CRASH TYPE - SIDE CONTACTS INJURIES window/pillar face brain neck door panel/intrusion bony thorax lungs hip pelvis

CRASH TYPE - REAR CONTACTS INJURIES head rest up scalp contusions head rest down usually soft tissue strain to neck seat back none shoulder belt on chest contusion flexion/rotation inj to C- spine

CRASH TYPE - FRONTAL CONTACTS BELTS ON INJURIES shoulder component lap belt alone clavicle bony thorax neck - flexion/rotation abdominal wall solid and hollow viscera - compressive above plus distraction L - spine

OTHER CRASH TYPES l Rollover l Ejection l Motor cycle l Bicycle l Pedestrian

INJURY BIOMECHANICS SUMMARY l Why bother ? l The science of stopping l Some examples of different mechanics and the injuries they produce l How we can learn more

MORE TO BE LEARNED l Crash investigation l Correlation with trauma registry data l Collision data project l Vehicle changes l Road design l Clinical data l Mechanics of other causes