Injury threshold: whiplash-associated disorders

[Whiplash injury of the neck from concepts to facts]

OBJECTIVES

To focus on a topic of traumatology and rehabilitation becoming recently a much debated public health problem.

METHOD

A references search from Medline database with whiplash as keyword was carried out. Were selected articles with abstracts in french or english and focusing on accidentology, biomechanics, demonstrated lesions, epidemiology and treatments.

RESULTS

From 1664 references found, 232 were reviewed. The usual mechanism of crash is a rear-end collision inducing in the occupants of the bumped vehicle a sudden lower cervical spine extension with upper flexion followed by a global flexion. In nearly 50% of the cases, the stress occurring in the collision is comparable to that observed in bumper cars. The velocity changes are seldom up to 15 km/h. A headrest at the level of the center of gravity of the head restrict significantly the extension of the neck. Every structure of the cervical spine could be damaged and mainly the facet joints but the lesions were only demonstrated in severes traumatisms. The discrepancies in incidence among the different countries could be related to their medicolegal system. Although subjectives, the early symptoms are rather similar among patients suggesting true anatomical or functional disorders but the chronicity seems to be mainly related to social and psychological factors. The association of: no posterior midline cervical tenderness, no intoxication, normal alertness, no focal neurological deficit and no painful distracting injuries has a good predictive value of the lack of osteo-articular lesion on X-rays. Except the grade IV of the Quebec task Force (0, no symptom; 1, pain and stiffness; 2, neck complaint and physical signs; 3, neck complaint and neurological signs; 4, fracture or dislocation) the use of a collar should be avoided and the cervical spine should be mobilized.

CONCLUSION

In most whiplash injuries, the mildness should be early stated, mobilization encouraged, and procedures of compensation shortened.

Whiplash associated disorders: a review of the literature to guide patient information and advice

OBJECTIVES

To review the literature and provide an evidence based framework for patient centred information and advice on whiplash associated disorders.

METHODS

A systematic literature search was conducted, which included both clinical and non-clinical articles to encompass the wide range of patients' informational needs. From the studies and previous reviews retrieved, 163 were selected for detailed review. The review process considered the quantity, consistency, and relevance of all selected articles. These were categorised under a grading system to reflect the quality of the evidence, and then linked to derived evidence statements.

RESULTS

The main messages that emerged were: physical serious injury is rare; reassurance about good prognosis is important; over-medicalisation is detrimental; recovery is improved by early return to normal pre-accident activities, self exercise, and manual therapy; positive attitudes and beliefs are helpful in regaining activity levels; collars, rest, and negative attitudes and beliefs delay recovery and contribute to chronicity. These findings were synthesised into patient centred messages with the potential to reduce the risk of chronicity.

CONCLUSIONS

The scientific evidence on whiplash associated disorders is of variable quality, but sufficiently robust and consistent for the purpose of guiding patient information and advice. While the delivery of appropriate messages can be both oral and written, consistency is imperative, so an innovative patient educational booklet, The Whiplash Book, has been developed and published.

Chronic pain/dysfunction in whiplash-associated disorders

OBJECTIVE

The purposes of this article are (1) to review current knowledge of and recent concepts pertaining to the causes of chronic pain and/or dysfunction following whiplash-type injuries and (2) to acquaint those who treat these types of injuries with possible mechanisms of continued pain and or dysfunction following whiplash.

DATA COLLECTION

A review of the literature on mechanisms of injury and neurologic considerations was undertaken. A hand search of relevant medical, neuroscience, chiropractic, and online Index Medicus sources and other sources involving mechanisms of nociception, neurotransmitters, and receptors that might evolve from whiplash-type soft tissue injuries was conducted.

RESULTS

Pain is a complex phenomenon that has great variability. Chronic pain appears to involve a deficient descending inhibitory process and/or ongoing excitatory input.

CONCLUSIONS

There is a wide variety of reactions by individuals to any given type of stimulus. Injury may lead to increases in neuronal activity and prolonged changes in the nervous system. Chronic pain may be seen as part of a central disturbance accompanied by disinhibition or sensitization of central pain modulation, mirrored in the immune and endocrine systems. Patients with chronic whiplash syndrome may have a generalized central hyperexcitability from a loss of tonic inhibitory input (disinhibition) and/or ongoing excitatory input contributing to dorsal horn hyperexcitability. Dysfunction of the motor system may also occur, with or without pain. The purpose of treatment should be not only to relieve pain but also to allow for proper proprioception.