Research Review by Dr. Michael Haneline©

Date Posted:

October 2009

Study Title:

The notion of a 'whiplash culture': a review of the evidence

Authors:

Haneline M

Author's Affiliations:

International Medical University, Kuala Lumpur, Malaysia and Palmer College of Chiropractic West, San Jose, CA USA.

Publication Information:

Journal of Chiropractic Medicine 2009; 8(3): 119-124.

Background Information:

Patients commonly seek chiropractic care for whiplash injuries. The majority of them recover in a matter of weeks or months, whereas some end up with chronic pain and impairment. Indeed, one study that involved 419 chronic neck pain patients reported that almost half of them thought that the source of their pain was a prior automobile collision.

Why some people develop chronic pain following a whiplash injury while others achieve a full recovery is not well understood. However, there is some evidence that certain risk factors (e.g., greater initial symptom severity and psychological factors) may contribute to prolonged symptoms.

Another explanation, and the topic of this review, has to do with the cultural expectations of the population where the injury occurred, which has been called a “whiplash culture”. Essentially, persons who live in countries where there is an expectation that people are prone to develop chronic pain following whiplash will be more likely to do so. In contrast, whiplash victims who live in countries without that kind of expectation are much less likely to become chronic.

A number of articles have been written about the reality of the whiplash culture premise and these articles have in turn been cited by other writers, but its basis has not been formally examined. Therefore, the purpose of this review was to locate and discuss all of the studies that were used in developing the whiplash culture concept, as well as to evaluate its plausibility.

Pertinent Results:

A total of 481 citations were retrieved, although most were eliminated because they did not actually report on the review’s topic or they were duplicates. Nineteen of the articles discussed the cultural aspects of whiplash and 8 of them were determined to have been used as a basis for developing the whiplash culture concept.

The 8 articles included:
  • Schrader et al., who had 202 subjects with whiplash complete retrospective questionnaires 1 to 3 years following involvement in rear-end collisions. This group was compared with 202 matched controls who had never been involved in an automobile crash. Cases were located from police department records in Kaunas, Lithuania, whereas controls were randomly selected from the general population. There was no significant difference between the groups and nobody ended up with disabling or persistent symptoms.
  • Obelieniene et al. conducted a study that used almost the identical methods to the study just mentioned, but it was carried out on headache patients. No patients reported increased headache after their automobile crash. Thus, the authors concluded that, since the results were obtained outside the medico-legal context, there was no support for a specific headache pattern that emerges 1-3 years after rear-end car collisions.
  • Ferrari et al. was yet another study that used very similar methods and even included the primary authors of the previous 2 studies. This study, also carried out in Lithuania, looked at 210 patients with temporomandibular disorders (TMD) and compared them with matched controls. They found a low prevalence of TMD symptoms in both groups and concluded that, unlike whiplash victims in Western societies, Lithuanian accident victims do not report chronic TMD symptoms following whiplash injuries.
  • Obelieniene et al. this time conducted a prospective study that followed 210 victims of rear-end collisions who were chosen from Kaunas, Lithuania police records. Questionnaires about neck pain and headache were mailed 2 months and 1 year after the accident. Controls were 210 matched subjects who were randomly taken from the population. There were some early differences between the groups, but no significant differences as to frequency and intensity of symptoms were found after 1 year.
  • Partheni et al. (including Ferrari) carried out a study in Greece that followed 180 whiplash victims for 6 months via a questionnaire that asked about neck pain, headache, shoulder pain, limb numbness or pain, and dizziness. Patients reported early symptoms, but more than 90% had recovered after 4-weeks and the rest returned to their pre-injury state of health with no instances of chronic disability. The authors concluded that symptoms following acute whiplash injury in Greece are self-limiting, brief, and do not progress into the so-called late whiplash syndrome.
  • Ferrari et al. conducted a study that compared the frequency and nature of expected whiplash symptoms in Lithuanians with those of Canadians. Subjects imagined having suffered a whiplash injury and then responded to a questionnaire that asked about a variety of symptoms that might be expected to arise from an injury. They were also asked how long they expected anticipated symptoms to persist. Anticipated symptoms were as expected, except about half of the Canadians thought their symptoms would last months or years, whereas very few Lithuanians did.
  • Ferrari et al. conducted virtually the same study as the previous one, except this time Canadians were compared with Greeks. The results were almost identical too, with about half of the Canadians anticipating long term symptoms, in contrast with only a few Greeks who did.
  • Ferrari and Lang once again compared anticipated symptoms following whiplash using Canadians and Germans this time, and ditto on the results.

Clinical Application & Conclusions:

The studies that were used to develop the whiplash culture concept have been criticized numerous times in the literature, mostly because they lack statistical power. For instance, the Norwegian Centre for Health Technology Assessment, a group established by the Department of Health and Social Affairs for Norway, indicated that more than 4000 persons would be needed in each group to have an 80% probability of finding a statistically significant difference; however, the studies only included about 200 subjects in their groups.

Carrol et al. suggested that there were methodological issues in the studies that may have affected their results, rather than just cultural expectations; including differences in the context in which the injuries occurred and differences in the countries' compensation policies that may have been responsible.

Ferrari advocates a biopsychosocial model to explain the differences in the rates of chronic whiplash between countries. Psychosocial factors in countries where the whiplash culture is present are blamed as the reason for these differences.

The “symptom expectation” theory is another model used as a basis in developing the whiplash culture concept. Basically, persons in some countries are prone to imagine having long term symptoms after a whiplash injury as compared with persons from other countries. However, the studies that were cited to support this theory are weak and/or not really relevant.

The notion of a whiplash culture is sometimes used to denigrate persons with long-term symptoms following whiplash. These patients are characterized as being caught up in a “herd mentality”, so to speak and therefore not sincere about their injuries. This weakens the veracity of many legitimately injured whiplash patients who happen to be unlucky enough to become chronic. In the eyes of an insurance claims representative, a jury, family members, etc., they may appear to be disingenuous.

In conclusion, there are sizeable holes in the whiplash culture theory that limit its usefulness. It may have a degree of merit to explain why some whiplash cases become chronic while others do not, but the evidence presented in this review did not adequately support it.

Study Methods:

The PubMed database was searched to locate articles that dealt with the subject of a whiplash culture. Those that did were examined to establish which studies were used in developing this concept.

Search terms included whiplash culture, whiplash, WAD, chronic, late, and long term. The search spanned from 1950 to June 2008 and only English language articles were retrieved. No chiropractic databases were searched because articles in chiropractic-specific journals do not typically report on this subject.

Study Strengths / Weaknesses:

First and foremost, one must keep in mind that this was not a systematic review. The search criteria were vague, only one database was searched, and the quality of the included articles was not assessed. Therefore, there was a risk of various biases affecting its results.

Being the author of this paper, I must admit that I entered this review thinking that the whiplash culture theory was not valid and wanted to know what evidence existed to support it and whether it was properly utilized. While the search was technically not systematic, a number of search terms were used in order to locate all relevant information on the topic. Only one database was searched because these types of studies are generally not found in chiropractic databases. Thus, the main risk of bias in this review was the way the articles were interpreted, which was reasonable in my opinion.

Additional References:

  1. Schrader H, Obelieniene D, Bovim G, et al. Natural evolution of late whiplash syndrome outside the medicolegal context. Lancet 1996; 347:1207-11.
  2. Obelieniene D, Bovim G, Schrader H, et al. Headache after whiplash: a historical cohort study outside the medico-legal context. Cephalalgia 1998; 18:559-64.
  3. Ferrari R, Schrader H, Obelieniene D. Prevalence of temporomandibular disorders associated with whiplash injury in Lithuania. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1999; 87:653-7.
  4. Obelieniene D, Schrader H, Bovim G, Miseviciene I, Sand T. Pain after whiplash: a prospective controlled inception cohort study. J Neurol Neurosurg Psychiatry 1999; 66:279-83.
  5. Partheni M, Constantoyannis C, Ferrari R, Nikiforidis G, Voulgaris S, Papadakis N. A prospective cohort study of the outcome of acute whiplash injury in Greece. Clin Exp Rheumatol 2000; 18:67-70.
  6. Ferrari R, Obelieniene D, Russell A, Darlington P, Gervais R, Green P. Laypersons' expectation of the sequelae of whiplash injury. a cross-cultural comparative study between Canada and Lithuania. Med Sci Monit 2002; 8:CR728-34.
  7. Ferrari R, Constantoyannis C, Papadakis N. Laypersons' expectation of the sequelae of whiplash injury: a cross-cultural comparative study between Canada and Greece. Med Sci Monit 2003; 9:CR120-4.
  8. Ferrari R, Lang C. A cross-cultural comparison between Canada and Germany of symptom expectation for whiplash injury. J Spinal Disord Tech 2005; 18:92-7.