The late whiplash syndrome: a biopsychosocial approach

Pain Catastrophizing: Controversies, Misconceptions and Future Directions

Recent reports have pointed to problems with the term "pain catastrophizing." Critiques of the term pain catastrophizing have come from several sources including individuals with chronic pain, advocates for individuals with chronic pain, and pain scholars. Reports indicate that the term has been used to dismiss the medical basis of pain complaints, to question the authenticity of pain complaints, and to blame individuals with pain for their pain condition. In this paper, we advance the position that the problems prompting calls to rename the construct of pain catastrophizing have little to do with the term, and as such, changing the term will do little to solve these problems. We argue that continued calls for changing or deleting the term pain catastrophizing will only divert attention away from some fundamental flaws in how individuals with pain conditions are assessed and treated. Some of these fundamental flaws have their roots in the inadequate training of health and allied health professionals in evidence-based models of pain, in the use of psychological assessment and intervention tools for the clinical management of pain, and in gender equity and antiracism. Critiques that pain scholars have leveled against the defining, operational, and conceptual bases of pain catastrophizing are also addressed. Arguments for reconceptualizing pain catastrophizing as a worry-related construct are discussed. Recommendations are made for remediation of the problems that have contributed to calls to rename the term pain catastrophizing. PERSPECTIVE: The issues prompting calls to rename the construct of pain catastrophizing have their roots in fundamental flaws in how individuals with pain are assessed and treated. Efforts to address these problems will require more than a simple change in terminology.

Placebo From an Enactive Perspective

Due to their complexity and variability, placebo effects remain controversial. We suggest this is also due to a set of problematic assumptions (dualism, reductionism, individualism, passivity). We critically assess current explanations and empirical evidence and propose an alternative theoretical framework—the enactive approach to life and mind—based on recent developments in embodied cognitive science. We review core enactive concepts such as autonomy, agency, and sense-making. Following these ideas, we propose a move from binary distinctions (e.g., conscious vs. non-conscious) to the more workable categories of reflective and pre-reflective activity. We introduce an ontology of individuation, following the work of Gilbert Simondon, that allow us to see placebo interventions not as originating causal chains, but as modulators and triggers in the regulation of tensions between ongoing embodied and interpersonal processes. We describe these interrelated processes involving looping effects through three intertwined dimensions of embodiment: organic, sensorimotor, and intersubjective. Finally, we defend the need to investigate therapeutic interactions in terms of participatory sense-making, going beyond the identification of individual social traits (e.g., empathy, trust) that contribute to placebo effects. We discuss resonances and differences between the enactive proposal, popular explanations such as expectations and conditioning, and other approaches based on meaning responses and phenomenological/ecological ideas.

Cues for feigning screening in whiplash associated disorders

The objective of this work is to evaluate the ability of a series of possible feigning indicators, extracted from relevant literature in the field, to discriminate between clinical patients with genuine symptomatology and instructed malingerers. A sample of 273 participants divided into two groups was used for this study: 153 whiplash associated disorder patients who were evaluated at a multidisciplinary medical center in the region of Murcia (Spain), between December 2017 and March 2019 and 120 healthy controls with malingering instructions, students of the Faculty of Medicine of the University of Murcia. In order for researchers to evaluate the indicators included in the study, a 22-step checklist (CDS) was developed, consisting of 22 criteria divided into 5 dimensions. Our results show that 18 of 22 indicators could discriminate between groups. Dimension 2 "Attitude toward the situation of illness" presented the greatest capacity for discrimination. In general terms, malingerers express a much more negative experience of the condition than the clinical patients.

The effect of steroid treatment on whiplash associated syndrome: a controlled randomized prospective trial

PURPOSE

There is significant evidence in the literature that low or relatively low cortisol concentrations near the time of an accident are associated with more severe forms of whiplash-associated disorders. We hypothesized that treating patients that were involved in a motor vehicle accident with hydrocortisone would alleviate the incidence and severity of these disabling disorders.

METHODS

A prospective, randomized, double-blind, placebo-controlled clinical trial. Blunt trauma patients that underwent a motor vehicle crash were allocated into a study group that received a single bolus of hydrocortisone and a control group that received saline. The patients were followed for 1 month. The incidence and severity of whiplash associated disorder, functional disturbances, and post-traumatic stress disorder were compared between the two groups. The analyses were repeated for sub-divisions into groups of high and low admission cortisol.

RESULTS

The more severe forms of whiplash-associated disorders on the day of accident were associated with low cortisol levels; mean cortisol concentration of the lower grade of whiplash patients (13.09 ± 7.35 µg%) was higher than that of whiplash syndrome of the severe forms (8.33 ± 3.45 µg), p = 0.001. There were no differences between study and control groups regarding whiplash-associated disorders, functional tests, and severity of stress disorder 1 month after the accident. Significant differences were evident between high and low cortisol sub-groups. Those who had low cortisol level on admission and received hydrocortisone had worse outcomes.

CONCLUSION

Steroid treatment of patients with whiplash might be harmful to those who present with low cortisol concentrations (< 9.5 μg/dL).

TRIAL REGISTRATION

Clinical Trials: Association between low cortisol levels and whiplash syndrome. Date of registration: March 18, 2014. Date the first participant was enrolled: May 10, 2014.

TRIAL REGISTRATION NUMBER

NCT02090309. URL: https://clinicaltrials.gov/ct2/show/NCT02090309 .

Biopsychosocial barriers affecting recovery after a minor transport-related injury: A qualitative study from Victoria

Objective

The aim of the study was to understand the recovery phenomena and to explore participants' perspectives on the biopsychosocial facilitators and barriers affecting their recovery after a minor transport injury.

Methods

A qualitative method was used involving semi‐structured interviews with 23 participants who sustained a minor transport injury. Interviews and analysis were guided by the biopsychosocial model (BPS) of health. The outcomes were themes capturing biopsychosocial barriers to, and personal experiences of, recovery using a previously defined framework.

Results

The themes indicate that recovery is a multifaceted phenomenon affected by comorbidities such as chronic pain, depression and anxiety. A range of subsequent complexities such as the inability to self‐care and undertaking daily domestic duties, and incapacity to participate in recreational activities were major barriers to recovery. These barriers were found to be an on‐going source of frustration, dissatisfaction and a perceived cause of depressive symptomatology in many participants. Most participants reported mixed feelings of the care received. Other common issues raised included a lack of understanding of the assessment time, regular follow‐up, guidance and on‐going support.

Conclusion

This study revealed that recovery after a minor transport‐related injury was a challenging, complex, demanding and a long‐term process for the individuals in this study. Findings from this limited cohort suggested that, for participants to return to their pre‐accident health status, a more coordinated approach to information and care delivery may be required.

Evidence and consensus recommendations for the pharmacological management of pain in India

Despite enormous progress in the field of pain management over the recent years, pain continues to be a highly prevalent medical condition worldwide. In the developing countries, pain is often an undertreated and neglected aspect of treatment. Awareness issues and several misconceptions associated with the use of analgesics, fear of adverse events - particularly with opioids and surgical methods of analgesia - are major factors contributing to suboptimal treatment of pain. Untreated pain, as a consequence, is associated with disability, loss of income, unemployment and considerable mortality; besides contributing majorly to the economic burden on the society and the health care system in general. Available guidelines suggest that a strategic treatment approach may be helpful for physicians in managing pain in real-world settings. The aim of this manuscript is to propose treatment recommendations for the management of different types of pain, based on the available evidence. Evidence search was performed by using MEDLINE (by PubMed) and Cochrane databases. The types of articles included in this review were based on randomized control studies, case-control or cohort studies, prospective and retrospective studies, systematic reviews, meta-analyses, clinical practice guidelines and evidence-based consensus recommendations. Articles were reviewed by a multidisciplinary expert panel and recommendations were developed. A stepwise treatment algorithm-based approach based on a careful diagnosis and evaluation of the underlying disease, associated comorbidities and type/duration of pain is proposed to assist general practitioners, physicians and pain specialists in clinical decision making.

Whiplash Syndrome Reloaded: Digital Echoes of Whiplash Syndrome in the European Internet Search Engine Context

Background

In many Western countries, after a motor vehicle collision, those involved seek health care for the assessment of injuries and for insurance documentation purposes. In contrast, in many less wealthy countries, there may be limited access to care and no insurance or compensation system.

Objective

The purpose of this infodemiology study was to investigate the global pattern of evolving Internet usage in countries with and without insurance and the corresponding compensation systems for whiplash injury.

Methods

We used the Internet search engine analytics via Google Trends to study the health information-seeking behavior concerning whiplash injury at national population levels in Europe.

Results

We found that the search for “whiplash” is strikingly and consistently often associated with the search for “compensation” in countries or cultures with a tort system. Frequent or traumatic painful injuries; diseases or disorders such as arthritis, headache, radius, and hip fracture; depressive disorders; and fibromyalgia were not associated similarly with searches on “compensation.”

Conclusions

In this study, we present evidence from the evolving viewpoint of naturalistic Internet search engine analytics that the expectations for receiving compensation may influence Internet search behavior in relation to whiplash injury.

Thermal Thresholds and Catastrophizing in Individuals with Chronic Pain after Whiplash Injury

Thermal sensitivity, thermal pain thresholds, and catastrophizing were examined in individuals with whiplash associated disorders (WAD) and in healthy pain-free participants. Quantitative sensory testing (QST) was used to measure skin sensitivity to cold and warmth and cold and heat pain thresholds over both the thenar eminence and the trapezius muscle (TrM) in 17 participants with WAD (age 50.8± 11.3 years) and 18 healthy participants (age 44.8± 10.2 years). The Pain Catastrophizing Scale (PCS) was used to determine pain coping strategies, and visual analogue scales were used for self-assessment of current background pain in individuals in the WAD group as well as experienced pain intensity and unpleasantness after QST and sleep quality in all participants. There were significant differences in warmth threshold and cold and heat pain thresholds of the TrM site between the WAD and pain-free groups. Significant differences between the two groups were also found for the catastrophizing dimension of helplessness in the PCS and in self-assessed quality of sleep. A correlational analysis showed that current background pain is significantly correlated with both cold discrimination and cold pain threshold in the skin over the TrM in individuals with WAD. These findings imply that thermal sensitivity is an important factor to consider in providing nursing care to individuals with WAD. Because biopsychosocial factors also influence the experience of pain in individuals with WAD, the role of nurses includes not only the description of the pain phenomenon but also the identification of relieving and aggravating factors.

Whiplash(-like) injury diagnoses and co-morbidities--both before and after the injury: A national registry-based study

Background

Previous studies suggest that a greater proportion of neck injury patients, whose injuries were sustained through whiplash accidents, become chronic due to a component of sickness-focusing. However, it is also possible that some of those with neck injuries were already more frail prior to the injury, resulting in more consequences from a certain intensity of injury. The objective of this study was to compare co-morbidity and mortality in people with a registered neck injury diagnosis, evaluated prior to and after the neck injury, to people without a registered neck injury evaluated at the same time-points.

Methods

From a hospital patient registry over a 12-year period, we identified those with the diagnosis ‘cervical-column distortion’ and matched four controls for each of them on sex, age, marital status and county of residence. For calculations of co-morbidity, those with an injury at year 1, who thus had no prior data, and for those at year 12 who did not have post data, were not included. The same applied to their individually matched controls. Health data for up to 3 years prior to and up to 3 years after the year of injury were recorded.

Results

We identified 94,224 cases and 373,341 controls. Those with registered neck injuries had 1.2-2.0 times more co-morbidities than controls after the injury, but had already had about the same (1.3-1.8 more co-morbidities) number of co-morbidities prior to the injury. Mortality up to 12 years was approximately the same in the two groups.

Conclusions

Those people having a registered neck injury had more co-morbidity diagnoses both before and after the injury than those without a registered neck injury. This suggests that the co-morbidities observed after the injury may be partly related to already existing general high health care-seeking and/or a low health status, rather than being entirely the consequence of the injury.

Course of recovery for whiplash associated disorders in a compensation setting

CONTEXT

The detailed course of recovery following compensable whiplash associated disorders (WAD) is not well understood. Some people recover within months and others report symptoms for extended periods. Recent research identified distinct recovery pathways. Identifying recovery pathways for people with this condition in compensable settings could assist clinical and claim management.

STUDY OBJECTIVE

This study aimed to identify recovery trajectories based on disability, pain catastrophising and mental health and, secondly, to examine developmental linkages between the trajectories.

STUDY DESIGN

A cohort of 246 people with compensable WAD were followed for 24 months after a motor vehicle related injury.

OUTCOME MEASURES

Functional Rating Index (FRI), Pain Catastrophising Scale (PCS) and the SF36 Mental Component Score (SF 36 MCS).

METHOD

Group-based trajectory analytical techniques were used to identify distinct post-injury profiles. Multinominal logistic regression modelling identified factors associated with membership of different trajectories.

RESULTS

246 people were enrolled a median of 72 days after injury. Three trajectories were identified for the measures used and their prevalences, respectively, were: for disability (FRI) they were mild (47%), moderate (31%), and severe (22%); for pain catastrophising (PCS) they were non-catastrophisers (55%), moderate-low catastrophisers (32%) and clinically significant catastrophisers (13%); and, for mental health (SF36 MCS) they were good mental health (40%), moderately low mental health (42%) and severely low mental health (18%). All groups showed no further recovery beyond 12 months after injury. The significant baseline predictors of the severe disability trajectory were: lower (that means worse) bodily pain scores (SF 36 BPS) (p≤0.01); high pain catastrophising (p≤0.01); and, self-reported fair or poor general health (p=0.03). Conditional probabilities for group membership showed that the three trajectories for both PCS and FRI were linked. Dual membership was high for the mild disability and mild pain catastrophising trajectories and, for the severe disability and clinically significant pain catastrophising trajectories.

CONCLUSIONS

There is a strong and plausible association between severe disability, clinical levels of pain catastrophising and low mental health. Claimants can be identified at claim notification based on three estimated recovery trajectories. Claim and clinical interventions can be targeted to the profile within each recovery trajectory.

Initial healthcare and coping preferences are associated with outcome 1 year after whiplash trauma: a multicentre 1-year follow-up study

OBJECTIVE

Individuals exposed to whiplash collisions have to cope with the stressful event as well as early physical symptoms. As in other chronic pain conditions, coping has been associated with outcome after whiplash. In this study, our aim was to examine whether initial coping preferences were associated with the development of chronic whiplash.

DESIGN

Prospective study.

SETTING

Primary care.

METHODS

740 acute whiplash patients were recruited from emergency units and general practitioners after car collisions in Denmark. Within 10 days postinjury, participants were asked what they believed could help them get better. At 12-month follow-up, the level of neck pain and capability to work was obtained. Whether coping preferences (baseline) were associated with outcome was investigated using multiple regression analyses.

RESULTS

Persistent neck pain was most strongly associated with preferring medications (mean difference=1.24 (95% CI 0.67 to 1.82)) and sickness absence (mean difference=1.18 (95% CI 0.53 to 1.82)). Reduced work capability was most strongly associated with preferring medications (OR=3.53 (95% CI 2.13 to 5.86)), sickness absence (OR=3.05 (95% CI 1.80 to 5.17)) and being referred to a physiotherapist/chiropractor (OR=3.03 (95% CI 1.33 to 6.91)). Active coping was associated with better outcomes: Participants preferring to change their lifestyle were protected against reduced work capability (OR=0.11 (95% CI 0.01 to 0.78)). Individuals who wanted to keep living as usual only (no other preference reported) were protected against neck pain (mean difference -1.62 (95% CI -2.39 to -0.84)) and reduced work capability (OR=0.09 (95% CI 0.01 to 0.64)).

CONCLUSIONS

A simple nine-item measure of coping preferences is associated with the development of chronic neck pain and reduced capability to work following whiplash trauma and may be used to identify individuals at risk of poor recovery.

On matters of causation in personal injury cases: Considerations in forensic examination

Rheumatologists are often called to be independent examiners of injured claimants and to address the question: "What is causing the injured person's symptoms?" This article deals with the legal principles that arise in these cases, including causation, convenient focus, secondary gain, and thin skull rules. We shall first set out two hypothetical scenarios of personal injury cases that set the scene for a discussion of legal principles in personal injury law. With the same two scenarios of personal injury in mind, we shall review the legal principles and the biopsychosocial models of the illnesses concerned and consider the importance of examiners going beyond diagnostic labels towards a more in-depth analysis of illness factors and mechanisms that in turn assist the trier of facts.

Less efficacious conditioned pain modulation and sensory hypersensitivity in chronic whiplash-associated disorders in Singapore

OBJECTIVES

Cultural differences in pain perception exist. Although chronic whiplash-associated disorder (WAD) is well investigated in western countries, little is known about its presentation in Singapore. We studied the neck motion and pain sensitivity in people with chronic WAD in Singapore.

MATERIALS AND METHODS

Thirty chronic WAD participants (>3 mo, Neck Disability Index: 40% [SD 17%]) were age, sex, and ethnicity matched with 30 pain-free controls. All 60 participants underwent the following tests: active neck motion, pain thresholds (pressure, brachial plexus provocation test [BPPT], cold), cold pain tolerance, and conditioned pain modulation (CPM). The test stimulus of contact heat and conditioning stimulus of cold water immersion was used to assess CPM. Data were evaluated to determine differences between WAD and control groups.

RESULTS

Active neck motion (F1,29=80.02), pain thresholds of blunt pressure (F1,29=20.84), BPPT (F1,29=54.56), and cold (Z=-4.31) were significantly lower in participants with WAD (P<0.0001). Cold pressor pain tolerance was significantly lower in participants with WAD (Z=-2.89, P=0.02). A less efficacious CPM was also demonstrated in participants with WAD (F1,29=9.20, P=0.03). A combination of BPPT and cold hyperalgesia best predicted the WAD group (sensitivity=96.7%, specificity=96.7%).

DISCUSSION

These findings of sensory hypersensitivity and decreased neck motion in Singaporeans with chronic WAD are consistent with physical impairments reported in western populations.

Factors related to non-recovery from whiplash. The Nord-Trøndelag Health Study (HUNT)

BACKGROUND

Whiplash injuries show a variable prognosis which is difficult to predict. Most individuals experiencing whiplash injuries rapidly recover but a significant proportion develop chronic symptoms and ongoing disability.

PURPOSE

By employing longitudinal data, we investigated how psychological and physical symptoms, self-rated health, use of health services and medications, health behavior and demographic factors predict recovery from whiplash.

METHOD

Data from two waves of a large, Norwegian, population-based study (The Nord-Trøndelag Health Study: HUNT2 and HUNT3) were used. Individuals reporting whiplash in HUNT2 (baseline) were identified in HUNT3 11 years later. The characteristics of individuals still suffering from whiplash in HUNT3 were compared with the characteristics of individuals who had recovered using Pearson's chi-squared test, independent sample t-tests and logistic regression.

RESULTS

At follow-up, 31.6 % of those reporting whiplash at baseline had not recovered. These individuals (n = 199) reported worse health at baseline than recovered individuals (n = 431); they reported poorer self-rated health (odds ratio [OR] = 3.12; 95 % confidence interval [CI], 2.20-4.43), more symptoms of anxiety (OR = 1.70; 95 % CI, 1.15-2.50), more diffuse somatic symptoms (OR = 2.38; 95 % CI, 1.61-3.51) and more musculoskeletal symptoms (OR = 1.21; 95 % CI, 1.13-1.29). Individuals still suffering from whiplash also visited more health practitioners at baseline (OR = 1.18; 95 % CI, 1.06-1.32) and used more medications (OR = 1.24; 95 % CI, 1.09-1.40).

CONCLUSION

Poor self-rated health seems to be a strong risk factor for whiplash injuries becoming chronic. Diffuse somatic symptoms, musculoskeletal symptoms and symptoms of anxiety at baseline are important prognostic risk factors. Knowledge of these maintaining risk factors enables identification of individuals at risk of non-recovery, facilitating adequate treatment for this vulnerable group.

Multidimensional associative factors for improvement in pain, function, and working capacity after rehabilitation of whiplash associated disorder: a prognostic, prospective outcome study

BACKGROUND

Whiplash associated disorders (WAD) have dramatic consequences for individual and public health. Risk factors for better and worse outcomes are important to optimize management. This study aimed to determine short- and mid-term associative co-factors of neck pain relief, improved physical functioning, and improved working capacity (dependent variables) in patients suffering from whiplash associated disorder who participated in a standardized, inpatient pain management program.

METHODS

Naturalistic, observational, prospective cohort study. Outcome was measured by standardized assessment instruments. Co-factors covered sociodemographics, comorbidities, social participation, affective health, and coping abilities. Stepwise, multivariate linear regression analysis was performed at discharge and at the 6-month follow-up.

RESULTS

All regression models explained high proportions of variance (53.3% - 72.1%). The corresponding baseline level was significantly associated with a change in every dependent variable (explained variances: 11.4%-56.7%). Pain relief significantly depended on improved function and vice-versa (3.4%-14.8%). Improved ability to decrease pain was associated with pain relief at discharge (9.6%). Functional improvement was associated with decreased catastrophizing (19.4%) at discharge and decreased depression (20.5%) at the 6 month follow-up.

CONCLUSIONS

Pain relief, improved physical function and working capacity were associated with each other. Improved coping (catastrophizing and ability to decrease pain) and reduced depression may act as important predictors for pain relief and improved function. These findings offer toe-holds for optimized therapy of chronic WAD.

What characterizes individuals developing chronic whiplash?: The Nord-Trøndelag Health Study (HUNT)

OBJECTIVE

Most individuals experiencing whiplash accidents recover rapidly. A considerable proportion, however, develop chronic symptoms. Psychological factors may slow recovery, possibly by increasing the likelihood of other symptoms being misattributed to, and amplified by the whiplash injury. We aimed to investigate how pre-injury mental and somatic symptoms, self-rated health, use of health-services and medications, health-behavior and socio-demographics predict the development of chronic whiplash.

METHODS

Data from two waves of a large, population based study (HUNT2 (baseline) and HUNT3) were used. Individuals reporting no whiplash at baseline were identified in HUNT3. Characteristics reported at baseline were compared between those who had developed chronic whiplash in HUNT3 (n=199) and those who had not (n=20,600), using Pearson's chi-squared tests, independent sample t-tests and logistic regression analyses.

RESULTS

Individuals developing chronic whiplash reported worse baseline health than those reporting no chronic whiplash. Poor self-rated health was a strong risk factor for subsequent chronic whiplash (OR=2.26, 95%CI: 1.68-3.04). Musculoskeletal pain also increased the risk (OR=1.21, 95%CI: 1.15-1.26), as did diffuse somatic symptoms (OR=2.09, 95%CI: 1.47-2.96), use of different health services (OR=1.31, 95%CI: 1.19-1.45), high use of medications (OR=1.28, 95%CI: 1.14-1.43) and symptoms of anxiety (OR=1.93, 95%CI: 1.39-2.68). Physical activity was protective (OR=0.67, 95%CI: 0.49-0.91). Most socio-demographic variables were not significantly associated with chronic whiplash.

CONCLUSION

Poor somatic and mental pre-injury health increased the risk of subsequent chronic whiplash. This suggests that chronic whiplash is not merely an organic disorder, and highlights the importance of individual expectations, symptom reattribution and amplification in development of chronic whiplash.

Somatic symptoms beyond those generally associated with a whiplash injury are increased in self-reported chronic whiplash. A population-based cross sectional study: the Hordaland Health Study (HUSK)

BACKGROUND

Chronic whiplash leads to considerable patient suffering and substantial societal costs. There are two competing hypothesis on the etiology of chronic whiplash. The traditional organic hypothesis considers chronic whiplash and related symptoms a result of a specific injury. In opposition is the hypothesis that chronic whiplash is a functional somatic syndrome, and related symptoms a result of society-induced expectations and amplification of symptoms. According to both hypotheses, patients reporting chronic whiplash are expected to have more neck pain, headache and symptoms of anxiety and depression than the general population. Increased prevalence of somatic symptoms beyond those directly related to a whiplash neck injury is less investigated. The aim of this study was to test an implication derived from the functional hypothesis: Is the prevalence of somatic symptoms as seen in somatization disorder, beyond symptoms related to a whiplash neck injury, increased in individuals self-reporting chronic whiplash? We further aimed to explore recall bias by comparing the symptom profile displayed by individuals self-reporting chronic whiplash to that among those self-reporting a non-functional injury: fractures of the hand or wrist. We explored symptom load, etiologic origin could not be investigated in this study.

METHODS

Data from the Norwegian population-based "Hordaland Health Study" (HUSK, 1997-99); N = 13,986 was employed. Chronic whiplash was self-reported by 403 individuals and fractures by 1,746. Somatization tendency was measured using a list of 17 somatic symptoms arising from different body parts and organ systems, derived from the research criteria for somatization disorder (ICD-10, F45).

RESULTS

Chronic whiplash was associated with an increased level of all 17 somatic symptoms investigated (p<0.05). The association was moderately strong (group difference of 0.60 standard deviation), only partly accounted for by confounding. For self-reported fractures symptoms were only slightly elevated. Recent whiplash was more commonly reported than whiplash-injury a long time ago, and the association of interest weakly increased with time since whiplash (r = 0.016, p = 0.032).

CONCLUSIONS

The increased prevalence of somatic symptoms beyond symptoms expected according to the organic injury model for chronic whiplash, challenges the standard injury model for whiplash, and is indicative evidence of chronic whiplash being a functional somatic syndrome.

Myofascial-entheseal dysfunction in chronic whiplash injury: an observational study

OBJECTIVES

To document any consistent clinical findings in a large cohort of patients with whiplash associated disorder.

DESIGN

Four-year observational study.

SETTING

Large orthopaedic medicolegal practice in the UK.

PARTICIPANTS

1025 consecutive cases of chronic whiplash associated disorder.

MAIN OUTCOME MEASURES

OBSERVATIONAL STUDY OF THE CLINICAL FEATURES OF WHIPLASH ASSOCIATED DISORDER: detailed examination

RESULTS

THREE CONSISTENT CLINICAL FEATURES: neck pain; reduced cervical spine range of motion; and myofascial-entheseal dysfunction. With regards to the myofascial-entheseal dysfunction there were trigger points in the upper, middle or lower trapezius; with or without enthesopathy in the lower or middle trapezius.

CONCLUSIONS

On the basis of this large observational experience we propose a clinically-based definition of chronic whiplash associated disorder: a painful syndrome following acceleration-deceleration injury with neck stiffness; and myofascial-entheseal dysfunction.

Catastrophizing and perceived injustice: risk factors for the transition to chronicity after whiplash injury

STUDY DESIGN

The article will summarize research that has supported the role of pain catastrophizing and perceived injustice as risk factors for problematic recovery after whiplash injury.

OBJECTIVE

This article focuses on two psychological variables that have been shown to impact on recovery trajectories after whiplash injury; namely pain catastrophizing and perceived injustice.

SUMMARY OF BACKGROUND DATA

Research has shown that psychological variables play a role in determining the trajectory of recovery after whiplash injury.

METHODS

This article will focus on two psychological variables that have been shown to impact on recovery trajectories after whiplash injury; namely pain catastrophizing and perceived injustice. The article will summarize research that has supported the role of pain catastrophizing and perceived injustice as risk factors for problematic recovery after whiplash injury.

RESULTS

Several investigations have shown that measures of catastrophizing and perceived injustice prospectively predict problematic trajectories of recovery after whiplash injury. Basic research points to the potential roles of expectancies, attention, coping and endogenous opioid dysregulation as possible avenues through which catastrophizing might heighten the probability of the persistence of pain after whiplash injury. Although research has yet to systematically address the mechanisms by which perceived injustice might contribute to prolonged disability in individuals with whiplash injuries, there are grounds for suggesting the potential contributions of catastrophizing, pain behavior and anger.

CONCLUSION

A challenge for future research will be the development and evaluation of risk factor-targeted interventions aimed at reducing catastrophizing and perceived injustice to improve recovery trajectories after whiplash injury.

Responsiveness of the cervical Northern American Spine Society questionnaire (NASS) and the Short Form 36 (SF-36) in chronic whiplash

Objective: To determine and compare the sensitivity to change of the condition-specific cervical Northern American Spine Society (NASS) and the generic Short Form 36 (SF-36).

Design: Prospective cohort study.

Subjects: One hundred and seventy five patients after whiplash injury.

Interventions: Four-week inpatient interdisciplinary pain management programme.

Main measures, analysis: Responsiveness of the NASS and the SF-36 was quantified by effect size and standardized response mean and compared within the same construct by the modified Jacknife test. Ability to detect improvement was compared using sensitivities determined from receiver operating characteristics curves.

Results: In pain, the NASS was comparable responsive to the SF-36 at the one-month follow-up ( n = 175): effect sizes: 0.62 (NASS) versus 0.61 (SF-36), P = 0.914. The NASS was less responsive than the SF-36 in function: 0.23 versus 0.63, P < 0.001 and in pain+function: 0.35 versus 0.58 ( P = 0.001). These relationships remained consistent using standardized response means, at the six-month follow-up ( n = 103), and in the comparison of the sensitivities. Sensitivities at one month, pain: 70% (NASS) versus 62% (SF-36), P = 0.234; function: 65% versus 80%, P = 0.002; pain+function: 68% versus 78%, P = 0.035. The six-month data were similar.

Conclusions: The generic SF-36 was more responsive in function and equally responsive in pain when compared to the condition-specific NASS. The SF-36 can be recommended as a responsive instrument for measurement of pain and function in chronic whiplash syndrome.

Reverse causality in the association between whiplash and symptoms of anxiety and depression: the HUNT study

STUDY DESIGN

Longitudinal population-based cohort study.

OBJECTIVE

The aim of this study was to examine the possibility of reverse causality, that is, if symptoms of anxiety and depression are associated with incident self-reported whiplash injury. The clinical relevance of self-reported whiplash injury was evaluated by its association with subsequent disability pension award.

SUMMARY OF BACKGROUND DATA

Whiplash is associated with an increased level of anxiety and depressive symptoms. This increase in psychological distress is generally understood as the consequence of the accident and related whiplash.

METHODS

Longitudinal data from the HUNT study was used. Baseline measures of symptoms of anxiety and depression were used in prediction of incident whiplash injury self-reported at follow-up 11 years later. Incident disability pension award was obtained from a comprehensive national registry during 2-year follow-up after self-reported whiplash injury.

RESULTS

Case-level symptom load of anxiety and depression at baseline increased the likelihood of reporting incident whiplash at follow-up (odds ratio [OR] = 1.60, 95% confidence interval = 1.22-2.11). Self-reported whiplash increased the chances of a subsequent disability pension award (OR = 6.54), even in the absence of neck pain (OR = 3.48).

CONCLUSION

This is the first published study with a prewhiplash prospective evaluation of psychological status. Our findings are in conflict with previous research suggesting whiplash to be the cause of associated psychological symptoms rather than their consequence. Self-reported whiplash injury was clinically relevant as it independently increased subsequent disability pension award. The strength of this effect, even in the absence of neck pain, suggests the ascertainment of this diagnostic label, or factors associated with this, are important predictors of disability.

The temporal development of fatty infiltrates in the neck muscles following whiplash injury: an association with pain and posttraumatic stress

BACKGROUND

Radiological findings associated with poor recovery following whiplash injury remain elusive. Muscle fatty infiltrates (MFI) in the cervical extensors on magnetic resonance imaging (MRI) in patients with chronic pain have been observed. Their association with specific aspects of pain and psychological factors have yet to be explored longitudinally.

MATERIALS AND FINDINGS

44 subjects with whiplash injury were enrolled at 4 weeks post-injury and classified at 6 months using scores on the Neck Disability Index as recovered, mild and moderate/severe. A measure for MFI and patient self-report of pain, loss of cervical range of movement and posttraumatic stress disorder (PTSD) were collected at 4 weeks, 3 months and 6 months post-injury. The effects of time and group and the interaction of time by group on MFI were determined. We assessed the mediating effect of posttraumatic stress and cervical range of movement on the longitudinal relationship between initial pain intensity and MFI. There was no difference in MFI across all groups at enrollment. MFI values increased in the moderate/severe group and were significantly higher in comparison to the recovered and mild groups at 3 and 6 months. No differences in MFI values were found between the mild and recovered groups. Initial severity of PTSD symptoms mediated the relationship between pain intensity and MFI at 6 months. Initial ROM loss did not.

CONCLUSIONS

MFI in the cervical extensors occur soon following whiplash injury and suggest the possibility for the occurrence of a more severe injury with subsequent PTSD in patients with persistent symptoms.

Clinical characteristics, pain, and disability in relation to alar ligament MRI findings

STUDY DESIGN

Cross-sectional study.

OBJECTIVE

To evaluate the association between degree of signal changes in the alar ligaments on MRI with respect to pain and disability.

SUMMARY OF BACKGROUND DATA

Conflicting evidence exists whether areas of high-signal intensity in the alar ligaments on MRI are associated with pain and disability.

METHODS

A cross-sectional designed study of 173 subjects including a group with persistent whiplash associated disorder (WAD) Grade II after a car accident (n = 59), a group with chronic nontraumatic neck pain (n = 57) and a group without neck pain or previous neck trauma (n = 57). To assess pain and disability, all participants filled in the Brief Pain Inventory (BPI-intensity and BPI-interference), the European Quality of Life (EQ-5D and EQ VAS) and the Hospital Anxiety and Depression Rating Scale (HADS). High-resolution proton-weighted MR images in three planes were evaluated by two experienced neuroradiologists who were blinded to patient history and group allocation. The alar ligaments were evaluated according to a 4-point grading scale; 0 = low-signal intensity throughout the entire cross-section area, 1 = high-signal intensity in one third or less, 2 = high-signal intensity in one third to two thirds, and 3 = high-signal intensity in two thirds or more of the cross-section area.

RESULTS

With respect to BPI and HADS, the scores were highest in the WAD group, intermediate in the chronic nontraumatic neck pain group, and lowest among controls. EuroQol scores were lowest in the WAD group, intermediate in the chronic nontraumatic neck pain group, and highest among controls (P < 0.001). There was, however, no significant correlation between the alar ligament changes and measures for pain and disability.

CONCLUSION

The previously reported assumption that changes in the alar ligaments detected on MRI are associated with pain and disability is not supported by this study. The diagnostic value and the clinical relevance of MR-detectable areas of high intensity in the alar ligaments remain questionable.

Whiplash injury prevention with active head restraint

BACKGROUND

Previous epidemiological studies have observed that an initial head restraint backset greater than 10 cm is associated with a higher risk of neck injury and persistent symptoms. The objective of this study was to investigate the relation between the active head restraint position and peak neck motion using a new human model of the neck.

METHODS

The model consisted of an osteoligamentous neck specimen mounted to the torso of a rear impact dummy and carrying an anthropometric head stabilized with muscle force replication. Rear impacts (7.1 and 11.1g) were simulated with and without the active head restraint. Physiologic rotation was determined from intact flexibility tests. Significant reductions (P<0.05) in the spinal motion peaks with the active head restraint, as compared to without, were identified. Linear regression analyses identified correlation between head restraint backset and peak spinal rotations (R(2)>0.3 and P<0.001).

FINDINGS

The active head restraint significantly reduced the average peak spinal rotations, however, these peaks exceeded the physiologic range in flexion at head/C1 and in extension at C4/5 through C7/T1. Correlation was observed between the head restraint backset and the extension peaks at C4/5 and C5/6.

INTERPRETATION

Correlation between head restraint backset and spinal rotation peaks indicated that a head restraint backset in excess of 8.0 cm may cause hyperextension injuries at the middle and lower cervical spine. The active head restraint may not be fully activated at the time of peak spinal motions, thus reducing its potential protective effects.

Symptom profile of persons self-reporting whiplash: a Norwegian population-based study (HUNT 2)

The aetiology of chronic whiplash associated disorder (WAD) is unclear and the condition has been perceived both as a chronic pain disorder, based on the injury to the neck, and as a functional somatic disorder. Based on the hypothesis that chronic WAD should be perceived as a functional somatic syndrome, we compared the symptom profile of persons with chronic WAD with the profile of persons with a functional somatic disorder, and with the profile of persons with an organic pain disorder. A sample of 55,046 persons participating in a Norwegian population-based health study (HUNT 2) was divided into four study groups: chronic WAD, fibromyalgia, rheumatoid arthritis, and controls (none of these disorders). Symptoms were categorized as pain and stiffness, cardiopulmonary and gastrointestinal symptoms, and mental disorders. Odds ratios (ORs) with 95% confidence intervals (CIs) from logistic regression were used to compare the prevalence of symptoms among the groups. The chronic WAD group had a significantly higher prevalence of symptoms from all body parts, across organ systems and also mental symptoms, compared to the control group. The fibromyalgia group had an even higher prevalence of all symptoms, while the rheumatoid arthritis group showed an increase in the prevalence of particularly pain and stiffness symptoms and also a minor increase in the prevalence of other symptoms compared to the control group. We conclude that this study provide evidence in favour of the hypothesis that chronic WAD should be perceived as a functional somatic syndrome. Persons with chronic WAD had a symptom profile more similar to people with a functional somatic disorder than an organic pain disorder, consisting of a wide array of symptoms, not only predominantly pain symptoms.

Psychological determinants of quality of life in patients with whiplash associated disorders-a prospective study

PURPOSE

To evaluate whether psychological factors and personality traits influence recovery in terms of quality of life in patients with subacute whiplash associated disorders (WAD).

METHOD

The data was obtained from a randomized controlled trial (RCT) on 47 patients. The patients completed measures of pain intensity, affective dimension of pain, pain location, psychological stress, heightened somatic awareness, depression, catastrophizing, self-efficacy, fear of movement (re)injury, and physical disability. After three months of physiotherapy interventions, the outcome of quality of life was measured with the Short Form Health survey (SF-12). All variables were entered in a multiple regression analysis, after controlling for age and sex.

RESULTS

Forty patients (85%) completed the trial. The self-efficacy scale (SES) was the only variable in the model that significantly explained the fraction of the SF12-score. The correlation between the SES and SF-12 was B = 0.64 (p < 0.01), and the adjusted R(2) was 0.40 (p < 0.05), which means that 40% of the variation in the SF12 outcomes was explained by the SES.

CONCLUSION

In order to improve health-related quality of life in patients with WAD, the present study stresses the importance of targeting self-efficacy. A special effort should be made to enhance these beliefs in the rehabilitation process.

The role of physical injury in motor and sensory conversion symptoms: a systematic and narrative review

OBJECTIVES

Conversion symptoms are currently conceptualized as physical symptoms induced by psychological trauma, conflict, or stress. Historical accounts also included physical injury as an important precipitant. We aimed to determine (a) the frequency of reported physical injury prior to onset in published studies of patients with motor or sensory conversion symptoms and (b) the clinical characteristics of patients in whom onset was associated with physical injury.

METHODS

Firstly, we employed a systematic review of all reports of adults with motor or sensory conversion symptoms published between 1965 and 2005. Secondly, we used a narrative review of the literature on this topic, especially possible mechanisms.

RESULTS

A total of 133 eligible studies, which recorded precipitating factors, including 869 patients, were found. Physical injury prior to symptom onset was reported in 324 patients (37%). Clinical features associated with physical injury included younger age, weakness (vs. movement disorder), paraparesis (vs. hemiparesis), and neurological versus psychiatric study settings.

CONCLUSIONS

Despite the current dominance of a psychological view of conversion symptoms, physical injury prior to onset has been frequently reported in papers published since 1965. While the data are of low quality, they nevertheless suggest that physical trauma has a role in many patients in the onset of motor and sensory conversion symptoms. We discuss possible mechanisms for this association.

Psychosocial and socio-demographic factors associated with outcomes for patients undergoing rehabilitation for chronic whiplash associated disorders: a pilot study

PURPOSE

Identify psychosocial and socio-demographic factors (measured prior to treatment) that were associated with post-treatment self-perceived pain and disability and two secondary outcomes: psychological distress, and return to work in patients undergoing multidisciplinary rehabilitation for chronic whiplash associated disorders (WAD).

METHOD

Interviews were conducted with 28 patients with chronic WAD at entry to and completion of an intensive rehabilitation program, and a telephone interview was carried out three months later. Participants completed pain and disability, and psychological distress questionnaires, at baseline and at both follow-ups. They also completed psychosocial questionnaires and provided socio-demographic information. The effect of each of the independent variables on the outcomes was first evaluated by simple regressions, and then subsequently by multiple regression analysis.

RESULTS

Higher baseline pain and disability predicted higher pain and disability at both follow-ups (p < 0.001), and higher psychological distress at program completion (p = 0.003). Younger age (p = 0.028) and higher baseline psychological distress (p = 0.002) were associated with higher psychological distress three months post-rehabilitation. Greater social support at work was prognostic of return to work at program completion (p = 0.04).

CONCLUSIONS

Baseline pain and disability was the only factor that affected pain and disability post-rehabilitation. Psychosocial factors played a role in the prognosis of psychological distress and return to work.

The anatomy and biomechanics of acute and chronic whiplash injury

Whiplash injury is the most common motor vehicle injury, yet it is also one of the most poorly understood. Here we examine the evidence supporting an organic basis for acute and chronic whiplash injuries and review the anatomical sites within the neck that are potentially injured during these collisions. For each proposed anatomical site--facet joints, spinal ligaments, intervertebral discs, vertebral arteries, dorsal root ganglia, and neck muscles--we present the clinical evidence supporting that injury site, its relevant anatomy, the mechanism of and tolerance to injury, and the future research needed to determine whether that site is responsible for some whiplash injuries. This article serves as a snapshot of the current state of whiplash biomechanics research and provides a roadmap for future research to better understand and ultimately prevent whiplash injuries.

Catastrophizing and causal beliefs in whiplash

STUDY DESIGN

Prospective cohort study.

OBJECTIVE

This study investigates the role of pain catastrophizing and causal beliefs with regard to severity and persistence of neck complaints after motor vehicle accidents. SUMMARY OF BACKGROUND DATA.: In previous research on low back pain, somatoform disorders and chronic fatigue syndrome, pain catastrophizing and causal beliefs were found to be related to perceived disability and prognosis. Furthermore, it has been argued with respect to whiplash that culturally dependent symptom expectations are responsible for a chronic course.

METHODS

Individuals involved in traffic accidents who initiated compensation claim procedures with a Dutch insurance company were sent questionnaires (Q1) containing the Neck Disability Index, the Pain Catastrophizing Scale, and the Causal Beliefs Questionnaire-Whiplash. Of 1252 questionnaires dispatched, 747 (59.7%) were returned. Only car occupants with neck complaints were included in this study (n = 140). Complaints were monitored using additional questionnaires administered 6 (Q2) and 12 months (Q3) after the accident.

RESULTS

Pain catastrophizing and causal beliefs were related to the severity of concurrent whiplash disability. The severity of initial complaints was related to the severity and persistence of whiplash complaints. Attributing initial neck complaints to whiplash was found to predict the persistence of disability at 6 and 12 months follow-up, over and above the severity of the initial complaints.

CONCLUSION

The results suggest that causal beliefs may play a major role in the perceived disability and course of neck complaints after motor vehicle accidents, whereas pain catastrophizing is predominantly related to concurrent disability.The current findings are consistent with the view that an early conviction that neck complaints are caused by the medico-cultural entity whiplash has a detrimental effect on the course of symptoms.

Magnetic resonance imaging assessment of the alar ligaments in whiplash injuries: a case-control study

STUDY DESIGN

Case-control study.

OBJECTIVE

To use high-resolution magnetic resonance imaging (MRI) in assessing signal intensity areas in the alar ligaments.

SUMMARY OF BACKGROUND DATA

Conflicting evidence exists whether areas of high signal intensity in the alar ligament on MRI are more frequent in whiplash patients than in noninjured control subjects.

METHODS

A case-control designed study of 173 subjects included one group with persistent whiplash associated disorder Grade I-II after a car accident (n = 59), one with chronic nontraumatic neck pain (n = 57) and one group without neck pain or previous neck trauma (n = 57). High-resolution proton-weighted MRI in 3 planes was used. The images were independently evaluated by two experienced neuroradiologists who were blinded to patient history and group allocation. The alar ligaments were evaluated according to a 4-point grading scale; 0 = low signal intensity throughout the entire cross section area, 1 = high signal intensity in one third or less, 2 = high signal intensity in one-third to two thirds, and 3 = high signal intensity in two thirds or more of the cross section area.

RESULTS

Alar ligament changes Grade 0 to 3 were seen in all 3 diagnostic groups. Areas of high signal intensity (Grade 2-3) were found in at least one alar ligament in 49% of the patients in the whiplash associated disorder Grade I-II group, in 33% of the chronic neck pain group and in 40% of the control group (chi, P = 0.22). CONCLUSION.: The previously reported assumption that these changes are due to a trauma itself is not supported by this study. The diagnostic value and the clinical relevance of magnetic resonance detectable areas of high intensity in the alar ligaments are questionable.

Are early MRI findings correlated with long-lasting symptoms following whiplash injury? A prospective trial with 1-year follow-up

Neck pain is the cardinal symptom following whiplash injuries. The trauma mechanism could theoretically lead to both soft tissue and bone injury that could be visualised by means of MRI. From previous quite small trials it seems that MRI does not demonstrate significant tissue damage. Large prospectively followed cohorts are needed to identify possible clinically relevant MRI findings. The objective of this trial was to evaluate (1) the predictive value of cervical MRI after whiplash injuries and (2) the value of repeating MRI examinations after 3 months including sequences with flexion and extension of the cervical spine. Participants were included after rear-end or frontal car collisions. Patients with fractures or dislocations diagnosed by standard procedures at the emergency unit were not included. MRI scans of the cervical spine were performed at baseline and repeated after 3 months. Clinical follow-ups were performed after 3 and 12 months. Outcome parameters were neck pain, headache, neck disability and working ability. A total of 178 participants had a cervical MRI scan on average 13 days after the injury. Traumatic findings were observed in seven participants. Signs of disc degeneration were common and most frequent at the C5-6 and C6-7 levels. Findings were not associated with outcome after 3 or 12 months. The population had no considerable neck trouble prior to the whiplash injury and the non-traumatic findings represent findings to be expected in the background population. Trauma-related MRI findings are rare in a whiplash population screened for serious injuries in the emergency unit and not related to a specific symptomatology. Also, pre-existing degeneration is not associated with prognosis.

Incidence and outcome of whiplash injury after multiple trauma

STUDY DESIGN

A retrospective study of 101 consecutive polytrauma patients with regard to whiplash injury.

OBJECTIVES

To investigate the incidence and evaluate long-term outcome of whiplash injury following high-energy trauma.

SUMMARY OF BACKGROUND DATA

Chronic whiplash injury has been widely reported in the literature, following low-energy trauma. Very few studies exist on whiplash injury following high-energy trauma.

METHODS

A total of 101 consecutive polytrauma patients admitted to our Level I Trauma Center over a 2-year period, fulfilling the inclusion criteria (age >18 years, high-energy trauma [a fall from a height >2 m, road traffic accidents with speed >30 km/h], and Injury Severity Score >16), were assessed. Whiplash injury was defined according to Quebec Task Force guidelines. The study group (n = 13) included patients who developed whiplash injury symptoms and the control group (n = 88) those who did not. The Neck Disability Index was calculated as an outcome measure for patients complaining of whiplash injury symptoms. The mean follow-up was 17 months. The chi2 and Student t tests were used for the statistical analysis (SPSS 12.1; SPSS, Inc., Chicago, IL).

RESULTS

Only 13 out of 101 patients (1 female/12 male) (13%) complained of whiplash injury. There was a significantly higher rate of neck pain at triage (P < 0.001) and higher combined mean of Abbreviated Injury Score of upper torso (P < 0.0001) in the study group, elucidating the cause of whiplash injury. The Neck Disability Index was <24 points, indicating only mild-to-moderate disability in these patients. Whiplash injury incidence in this study (13%) was similar to the incidence of neck pain in the general population.

CONCLUSIONS

The incidence of whiplash injury following polytrauma was found to be low in our study. There is no dose-response relation between magnitude of trauma severity and incidence of whiplash injury.

[Problems involved in expert opinions on acceleration injuries of the cervical spine]

Reasons for problems in stating an expert opinion on acceleration injuries of the cervical spine are numerous. The presence of unexpected or the absence of expected symptoms, the lack of objective proof for alterations or the presence of complaints that are difficult to prove, the discrepancy between recognizable force of the impact versus the resulting damage to the injured as well as the chance of being completely incapable of rendering proof that unquestionably a potentially damage-causing event is--beyond any reasonable doubt--the origin of an observed alteration in an injured individual are some of the problems a medical expert has to face when dealing with the analysis of injuries of the cervical spine. Unsatisfactory documentation in the patient's records, discussions about the reliability of diagnostic means or the interpretation of their results, difficult to procure evidence of accident-specific biomechanics and their direct or indirect impact on the body or neck of the injured person as well as distinguishing cervical sprain from mild brain damage, post-traumatic distress syndrome, cognitive disorder, psychiatric disease, aggravation, or malingering makes it hard for an expert to state an expert opinion.

Whiplash following rear end collisions: a prospective cohort study

OBJECTIVE

The purpose of this study was to investigate the factors which predict neck pain initially and at 1 year following a rear end collision.

METHODS

All people who reported a rear end collision to the Devon and Cornwall Constabulary were identified and formed the basis of the cohort. People were excluded if they were under 18 years of age or had suffered a head injury. The main outcome measures were neck pain lasting for more than a week after the accident and neck pain at least 1 day a week at 1 year. Logistic regression was used to investigate associations between demographic and accident related variables and outcomes.

RESULTS

A total of 1147 people reported rear end collisions to the police during the study period and 503 (44%) agreed to take part in the study. Of the respondents, 78% had neck pain lasting for more than a week and 52% still had pain at 1 year. Age (odds ratio, 95% confidence interval: 0.957, 0.942-0.972) and prior history of neck pain (8.32, 2.89-23.89) were the most important predictors of early neck pain. The most important predictors of pain at 1 year were the initial neck visual analogue scale (VAS) score (1.03, 1.01-1.05) and the presence of a compensation claim (4.09, 1.62-10.32). There was only weak evidence that measures of the severity of the impact were associated with outcomes.

CONCLUSION

Demographic variables and the presence of a compensation suit show the strongest correlation with acute and chronic neck pain following rear end collisions.