As a diagnosis whiplash is as irritating as lumbago or ague. In a book written by a clever bloke called Arthur Croft and some co-workers called, ironically,
“Whiplash Injuries, The Cervical Acceleration/Deceleration Syndrome, third edition”
They say that the term whiplash has evolved now into a vague, non-descriptive diagnosis of the problem described by patients about their major symptoms of neck pain after motion trauma.
Croft says that there have been calls for the diagnosis name to be updated to be more descriptive and injury relevant, such as acceleration/deceleration trauma or hyperextension/hyperflexion trauma. However, the latter diagnosis would hint that the injury was caused by an initial hyperextension, followed by hyperflexion of the neck but, if the injuries occurred in reverse, the diagnosis may need to reflect the reverse and become hyperflexion/hyperextension.
Additionally, in high acceleration, the sudden head and neck rotation backwards may cause significant hard (bone and cartilidge) and soft (tendon, ligament and muscle) tissue damage, as seen in cervical ‘whiplash’, which is unique to this type of injury. So, hyperextension and/or hyperflexion of the neck is not pre-requisite to such an injury and, as many patients cannot accurately remember the exact direction of force after an accident, this terminology would be obsolete.
Interestingly, there has been some research done that suggests, and I think with ‘authority’, that the main mechanism of injury is not the flexion and extension bit but the lateral translation. Bearing in mind that 40 mph is the same as 58.6 feet per second and, if you are hit from behind, your body, pushed by your seat, will accelerate to over 50 feet per second in less than a second. At the same time your head remains relatively stationary. So, there is a huge difference in speed between these two parts of your body, the main body mass travelling at about 50 feet per second and the head at about 0 feet per second. The damage this will cause is pretty significant and stretches and snaps ligaments and tendons, crushes soft tissue and can fracture bones.
The term has become most associated with rear-impact collision but it has also been used by various practitioners for any generally harmful motion or impact to the cervical spine, unrelated to the direction of force or size of force.
Croft calls for the use of the more descriptive diagnostic term “cervical acceleration/deceleration injury”. The term does not give an estimation of direction of the force and, if the accident was a frontal impact, the term could be reduced to cervical deceleration injury but a side on impact injury would be expanded to lateral cervical acceleration/deceleration or lateral CAD injury.
