Project: Biomechanics and the Evaluation of Whiplash Associated Disorder (WAD) Injury

Reference: S0010/VF

Last update: 04/02/2005 10:56:42


The objectives of this project are to:

* extend current knowledge on accident conditions resulting in whiplash injury, including oblique - and frontal impacts;
* extend current knowledge on human neck behaviour in low speed accident conditions;
* develop a prototype crash dummy suitable for safety assessment for rear, frontal and lateral (oblique) impacts;
* develop a mathematical computer model of the developed crash dummy to be used as a CAD tool to support the industrial design process;
* develop a test method to assess the protection offered by a seat including the head restraint and the complete restraint system; and
* develop guidelines for the performance principles of safe seats and restraint systems, including a demonstrator.


It has been recognised that soft tissue cervical-sprain injuries, whilst typically classified as minor, can have long lasting and disabling effects, with sufferers often taking extended periods off work and with high after-care health and societal costs. However, neither the injury mechanism nor the injuries themselves have been well defined or understood and for this reason, the term Whiplash Associated Disorder (WAD) is often used. WAD injury is a very important and difficult subject area. It is reported to occur in impacts from all directions, but thought to be more prevalent following rear impacts. Ultimately, some form of regulatory test may be necessary to reduce the severity and incidence of WAD injury for vehicle occupants. A number of different injury mechanisms for WAD have been proposed which suggest that it is not a single injury, but a term used to refer to a group of symptoms. Before a validated and well supported test procedure for the mitigation of WAD can be developed, further understanding of WAD injury is necessary. This must be linked with an understanding of the way the new generation of rear impact dummies behave, predict injury and what their limitations are. New seat designs have been developed to attempt to mitigate WAD injury and it is essential that such seats do not transfer injuries from one body region to another. Hence, dummies developed to assess injury must be sensitive to all loadings from the vehicle seat.

This project supported the UK's participation in the EC 5th Framework project Whiplash II, developed through the Passive Safety Network group; a body co-ordinating EC supported research projects. The aims of the new EC project were broader than just rear impact and were to produce a new dummy capable of detecting whiplash injuries from frontal, oblique-frontal, rear and oblique-rear impacts and develop injury criteria for rear impacts.


TRL Limited
Crowthorne House, Nine Mile Ride, Wokingham, Berkshire, RG40 3GA
+44 (0)1344 773131

Contract details

Cost to the Department: £352,533.00

Actual start date: 12 April 2002

Actual completion date: 30 November 2004


PR/SE/553/02. Whiplash Injury - A Summary Report of the Literature Base (1998 to 2002)
Author: TRL Ltd
Publication date: 27/07/2002
Source: Contact:

PR/SE/668/03. Human Responses in Rear-Oblique Impact Including Dummy Design and Assessment Targets
Author: TRL Ltd
Publication date: 01/09/2003
Source: Contact:

PR/SE/069/04. Biomechanics and the Evaluation of Whiplash Associated Disorder (WAD) Injury. Final Report
Author: TRL Ltd
Publication date: 07/12/2004
Source: Contact:

Summary of results

  1. The project has provided original research and conclusions concerning oblique rear impact loading of vehicle occupants. The majority of work on tools to mitigate whiplash and its associated disorders have been based upon a two-dimensional motion of the head and neck caused by a pure rear impact. This research has generated response corridors for the oblique rear impact scenario which should be used alongside those generated for pure rear impact, if there is any possibility that dummies may be exposed to asymmetric loading.

    The work has increased the evidence to suggest that currently available dummies and injury criteria are not sufficiently advanced to enable injury risk assessment in rear impact.

    The research has highlighted the limits to current understanding of the injury mechanim(s) that cause the symptoms of 'Whiplash' (WAD) and made clear recommendations to address this lack of scientific knowledge.