Physical and psychological factors maintain long-term predictive capacity post-whiplash injury

Whiplash and the compensation hypothesis

STUDY DESIGN

Review article.

OBJECTIVE

To explain why the evidence that compensation-related factors lead to worse health outcomes is not compelling, either in general, or in the specific case of whiplash.

SUMMARY OF BACKGROUND DATA

There is a common view that compensation-related factors lead to worse health outcomes ("the compensation hypothesis"), despite the presence of important, and unresolved sources of bias. The empirical evidence on this question has ramifications for the design of compensation schemes.

METHODS

Using studies on whiplash, this article outlines the methodological problems that impede attempts to confirm or refute the compensation hypothesis.

RESULTS

Compensation studies are prone to measurement bias, reverse causation bias, and selection bias. Errors in measurement are largely due to the latent nature of whiplash injuries and health itself, a lack of clarity over the unit of measurement (specific factors, or "compensation"), and a lack of appreciation for the heterogeneous qualities of compensation-related factors and schemes. There has been a failure to acknowledge and empirically address reverse causation bias, or the likelihood that poor health influences the decision to pursue compensation: it is unclear if compensation is a cause or a consequence of poor health, or both. Finally, unresolved selection bias (and hence, confounding) is evident in longitudinal studies and natural experiments. In both cases, between-group differences have not been addressed convincingly.

CONCLUSION

The nature of the relationship between compensation-related factors and health is unclear. Current approaches to testing the compensation hypothesis are prone to several important sources of bias, which compromise the validity of their results. Methods that explicitly test the hypothesis and establish whether or not a causal relationship exists between compensation factors and prolonged whiplash symptoms are needed in future studies.

Does knowledge of predictors of recovery and nonrecovery assist outcomes after whiplash injury?

STUDY DESIGN

Nonsystematic review.

OBJECTIVE

Review of prognostic indicators for outcome after whiplash injury and the implications for clinical practice and future research.

SUMMARY OF BACKGROUND DATA

The capacity to predict outcome after whiplash injury is important to guide the management of the condition. There have now been numerous cohort studies and several systematic reviews of prognosis. It is not clear if the current knowledge of prognostic indicators is useful for clinical practice and to improve outcomes after injury.

METHODS

Nonsystematic review of research investigating the prediction of chronic pain/disability and psychological outcomes after whiplash injury.

RESULTS

There remains considerable uncertainty surrounding the identification of clear prognostic indicators after whiplash injury. All systematic reviews note the moderate or lower quality if primary cohort studies and only one systematic review performed meta-analysis. There have been no studies attempting validation of predictive models. At the present time, the knowledge base stands that higher initial pain levels are the most consistent predictor of poor functional recovery. Additional promising factors include physical factors of cold hyperalgesia and loss of neck range of movement, although the latter is inconsistent. Psychological factors of pain catastrophizing, symptoms of post-traumatic stress and recovery perceptions are also prognostic of poor recovery and the presence of depressed mood is inconsistent. Further research is needed to validate predictive models, investigate interactions between factors, and to determine whether modification of predictors is possible and leads to improved outcomes.

CONCLUSION

The understanding of factors predictive of poor recovery after whiplash injury is evolving. Although more research is required to validate predictive models, some factors show consistent predictive capacity and could be used in clinical practice as potential indicators of poor recovery. It is not known if the specific targeting of modifiable prognostic indicators can be achieved or will lead to improved outcomes.

Whiplash-associated disorder: musculoskeletal pain and related clinical findings

The aim of this paper was to review the physical and psychological processes associated with whiplash-associated disorders. There is now much scientific data available to indicate the presence of disturbed nociceptive processing, stress system responses, muscle and motor changes as well as psychological factors in both acute and chronic whiplash-associated disorders. Some of these factors seem to be associated with the transition from acute to chronic pain and have demonstrated prognostic capacity. Further investigation is required to determine if these processes can be modified and if modification will lead to improved outcomes for this condition. The burden of whiplash injuries, the high rate of transition to chronicity, and evidence of limited effects of current management on transition rates demand new directions in evaluation and management. The understanding of processes underlying this condition is improving and this lays the foundation for the development of more effective management approaches.

Pressure pain threshold testing demonstrates predictive ability in people with acute whiplash

STUDY DESIGN

Longitudinal cohort study.

OBJECTIVES

To determine whether pressure pain threshold (PPT), tested at 2 standardized sites, could provide additional prognostic ability to predict short-term outcomes in people with acute whiplash, after controlling for age, sex, and baseline pain intensity.

BACKGROUND

PPT may be a valuable assessment and prognostic indicator for people with whiplash-associated disorder. The extent to which PPT can predict short-term disability scores has yet to be explored in people with acute (of less than 30 days in duration) whiplash-associated disorder in a clinical setting.

METHODS

Eligible patients were recruited from community-based physiotherapy clinics in Canada. Baseline measurements included PPT, as well as pain intensity, age, and sex. Neck-related disability was collected with the Neck Disability Index 1 to 3 months after PPT testing. Multiple linear regression models were constructed to evaluate the unique contribution of PPT in the prediction of follow-up disability scores.

RESULTS

A total of 45 subjects provided complete data. A regression model that included sex, baseline pain intensity, and PPT at the distal tibialis anterior site was the most parsimonious model for predicting short-term Neck Disability Index scores 1 to 3 months after PPT testing, explaining 38.6% of the variance in outcome. None of the other variables significantly improved the predictive power of the model.

CONCLUSION

Sex, pain intensity, and PPT measured at a site distal to the injury were the most parsimonious set of predictors of short-term neck-related disability score, and represented promising additions to assessment of traumatic neck pain. Neither age nor PPT at the local site was able to explain significant variance beyond those 3 predictors. Limitations to interpretation are addressed.

Reliability, standard error, and minimum detectable change of clinical pressure pain threshold testing in people with and without acute neck pain

STUDY DESIGN

Clinical measurement.

OBJECTIVES

To evaluate the intrarater, interrater, and test-retest reliability of an accessible digital algometer, and to determine the minimum detectable change in normal healthy individuals and a clinical population with neck pain.

BACKGROUND

Pressure pain threshold testing may be a valuable assessment and prognostic indicator for people with neck pain. To date, most of this research has been completed using algometers that are too resource intensive for routine clinical use.

METHODS

Novice raters (physiotherapy students or clinical physiotherapists) were trained to perform algometry testing over 2 clinically relevant sites: the angle of the upper trapezius and the belly of the tibialis anterior. A convenience sample of normal healthy individuals and a clinical sample of people with neck pain were tested by 2 different raters (all participants) and on 2 different days (healthy participants only). Intraclass correlation coefficient (ICC), standard error of measurement, and minimum detectable change were calculated.

RESULTS

A total of 60 healthy volunteers and 40 people with neck pain were recruited. Intrarater reliability was almost perfect (ICC = 0.94-0.97), interrater reliability was substantial to near perfect (ICC = 0.79-0.90), and test-retest reliability was substantial (ICC = 0.76-0.79). Smaller change was detectable in the trapezius compared to the tibialis anterior.

CONCLUSIONS

This study provides evidence that novice raters can perform digital algometry with adequate reliability for research and clinical use in people with and without neck pain.

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.

Impaired performance on the angle board test is induced in a model of painful whiplash injury but is only transient in a model of cervical radiculopathy

Although clinical studies report motor impairment associated with some painful injuries of the neck, assessment of motor function in animal models has been largely limited only to studies of direct trauma to the nervous system. The incline plane test was modified to evaluate motor function in two rodent pain models of facet joint distraction (FJD) and nerve root compression (NRC) injury (n = 5/group). Sham groups were also included as controls. Motor function was measured using the modified inclined plane test with rats facing downward before surgery (baseline) and following surgery on days corresponding to when mechanical sensitivity is established and remains elevated. Mean baseline values of the board angle inducing slip for FJD (45.8 ± 3.1°) was significantly greater (p = 0.014) than that for NRC (43.5 ± 2.5°), but baseline measurements did not vary for either group over time. No changes in motor function were found for shams. Motor function after FJD significantly decreased (p < 0.001) at days 1 and 7 after injury. In contrast, at day 1 after NRC injury, slip occurred at significantly lower (p = 0.0016) incline angles, but returned to baseline levels by day 7. These results show motor function impairment is induced following painful FJD and suggest the incline plane test offers utility to evaluate functional deficits in painful injuries.

Identifying predictors of early non-recovery in a compensation setting: The Whiplash Outcome Study

CONTEXT

People with Whiplash Associated Disorder (WAD) often experience pain and disability for extended periods of time. A large proportion of these people will seek treatment through a compensation process. Rarely is data related to people's health collected within the compensation process making it difficult to identify those that are at risk of delayed recovery and appropriately direct interventions.

STUDY OBJECTIVE

To compare people with WAD who have recovered with those that have not, within 3 months of injury and identify potential predictors of poorer health and non-recovery to inform claim screening processes.

STUDY DESIGN

Cross-sectional analysis of a cohort study.

PARTICIPANTS

People who sustained a WAD and claimed compensation within an Australian Motor Accidents Compensation Scheme between November 2007 and June 2009. MEASURE OF RECOVERY: Functional Rating Index (FRI) score (25). HEALTH OUTCOME MEASURES: Short Form 36 (SF36), FRI, and the Pain Catastrophising Scale (PCS).

METHODS

246 people who had lodged a claim for compensation were enrolled in the Whiplash Outcome Study within 3 months of sustaining a WAD injury. Participants were assigned to a recovered or non recovered group and analysed for differences between the two groups. Multiple linear regression models were used to identify potential predictors of poorer health and non-recovery.

RESULTS

Overall 23% of the study population had recovered within 3 months of sustaining a WAD, whilst only 9% had finalised their insurance claim. The recovered group had significantly better scores on all health outcome measures; SF36 Physical Component Score, SF36 Mental Component Score and the PCS(p < 0.001). The significant independent predictors of poorer health and non-recovery were helplessness(p < 0.001), older age (p < 0.001) and pre-injury work status being affected (p < 0.001) (r(2) = .624).Regardless of the health outcome measure used, helplessness was significantly associated with poorer reported health.

CONCLUSION

Including additional information at claim notification, specifically the PCS and information on the effect the injury has on the working population could significantly improve claim screening processes, identifying those with poorer health and risk of non-recovery.

Are MRI high-signal changes of alar and transverse ligaments in acute whiplash injury related to outcome?

Background

Upper neck ligament high-signal changes on magnetic resonance imaging (MRI) have been found in patients with whiplash-associated disorders (WAD) but also in non-injured controls. The clinical relevance of such changes is controversial. Their prognostic role has never been evaluated. The purpose of this study was to examine if alar and transverse ligament high-signal changes on MRI immediately following the car accident are related to outcome after 12 months for patients with acute WAD grades 1-2.

Methods

Within 13 days after a car accident, 114 consecutive acute WAD1-2 patients without prior neck injury or prior neck problems underwent upper neck high-resolution proton-weighted MRI. High-signal changes of the alar and transverse ligaments were graded 0-3. A questionnaire including the impact of event scale for measuring posttraumatic stress response and questions on patients' expectations of recovery provided clinical data at injury. At 12 months follow-up, 111 (97.4%) patients completed the Neck Disability Index (NDI) and an 11-point numeric rating scale (NRS-11) on last week neck pain intensity. Factors potentially related to these outcomes were assessed using multiple logistic regression analyses.

Results

Among the 111 responders (median age 29.8 years; 63 women), 38 (34.2%) had grades 2-3 alar ligament changes and 25 (22.5%) had grades 2-3 transverse ligament changes at injury. At 12 months follow-up, 49 (44.1%) reported disability (NDI > 8) and 23 (20.7%) neck pain (NRS-11 > 4). Grades 2-3 ligament changes in the acute phase were not related to disability or neck pain at 12 months. More severe posttraumatic stress response increased the odds for disability (odds ratio 1.46 per 10 points on the impact of event scale, p = 0.007) and so did low expectations of recovery (odds ratio 4.66, p = 0.005).

Conclusions

High-signal changes of the alar and transverse ligaments close after injury did not affect outcome for acute WAD1-2 patients without previous neck problems. High-resolution upper neck MRI has limited value for the initial examination and follow-up of such patients.

Neuronal hyperexcitability in the dorsal horn after painful facet joint injury

Excessive cervical facet capsular ligament stretch has been implicated as a cause of whiplash-associated disorders following rear-end impacts, but the pathophysiological mechanisms that produce chronic pain in these cases remain unclear. Using a rat model of C6-C7 cervical facet joint capsule stretch that produces sustained mechanical hyperalgesia, the presence of neuronal hyperexcitability was characterized 7 days after joint loading. Extracellular recordings of spinal dorsal horn neuronal activity between C6 and C8 (117 neurons) were obtained from anesthetized rats, with both painful and non-painful behavioral outcomes established by the magnitude of capsule stretch. The frequency of neuronal firing during noxious pinch (p<0.0182) and von Frey filaments applications (4-26g) to the forepaw was increased (p<0.0156) in the painful group compared to the non-painful and sham groups. In addition, the incidence and frequency of spontaneous and after discharge firing were greater in the painful group (p<0.0307) relative to sham. The proportion of cells in the deep laminae that responded as wide dynamic range neurons also was increased in the painful group relative to non-painful or sham groups (p<0.0348). These findings suggest that excessive facet capsule stretch, while not producing visible tearing, can produce functional plasticity of dorsal horn neuronal activity. The increase in neuronal firing across a range of stimulus magnitudes observed at day 7 post-injury provides the first direct evidence of neuronal modulation in the spinal cord following facet joint loading, and suggests that facet-mediated chronic pain following whiplash injury is driven, at least in part, by central sensitization.

Use of muscle functional magnetic resonance imaging to compare cervical flexor activity between patients with whiplash-associated disorders and people who are healthy

BACKGROUND

Chronic whiplash-associated disorders (WAD) have been shown to be associated with motor dysfunction. Increased electromyographic (EMG) activity in neck and shoulder girdle muscles has been demonstrated during different tasks in participants with persistent WAD. Muscle functional magnetic resonance imaging (mfMRI) is an innovative technique to evaluate muscle activity and differential recruitment of deep and superficial muscles following exercise.

OBJECTIVE

The purpose of this study was to compare the recruitment pattern of deep and superficial neck flexors between patients with WAD and controls using mfMRI.

DESIGN

A cross-sectional design was used.

METHOD

The study was conducted in a physical and rehabilitation medicine department. The participants were 19 controls who were healthy (10 men, 9 women; mean [+/-SD] age=22.2+/-0.6 years) and 16 patients with WAD (5 men, 11 women; mean [+/-SD] age=32.9+/-12.7 years). The T2 values were calculated for the longus colli (Lco), longus capitis (Lca), and sternocleidomastoid (SCM) muscles at rest and following cranio-cervical flexion (CCF).

RESULTS

In the overall statistical model for T2 shift, there was a significant main effect for muscle (F=3.906, P=.033) but not for group (F=2.855, P=.101). The muscle x group interaction effect was significant (F=3.618, P=.041). Although not significant, there was a strong trend for lesser Lco (P=.061) and Lca (P=.060) activity for the WAD group compared with the control group. Although the SCM showed higher T2 shifts, this difference was not significant (P=.291).

LIMITATIONS

Although mfMRI is an innovative and useful technique for the evaluation of deep cervical muscles, consideration is required, as this method encompasses a postexercise evaluation and is limited to resistance types of exercises.

CONCLUSIONS

Muscle functional magnetic resonance imaging demonstrated a difference in muscle recruitment between the Lco, Lca, and SCM during CCF in the control group, but failed to demonstrate a changed activity pattern in the WAD group compared with the control group. The mild symptoms in the WAD group and the wide variability in T2 values may explain the lack of significance.

Differential development of sensory hypersensitivity and a measure of spinal cord hyperexcitability following whiplash injury

Widespread sensory hypersensitivity is present in acute whiplash and is associated with poor recovery. Decreased nociceptive flexion reflex (NFR) thresholds (spinal cord hyperexcitability) are a feature of chronic whiplash but have not been investigated in the acute to chronic injury stage. This study compared the temporal development of sensory hypersensitivity and NFR responses from soon after injury to either recovery or to transition to chronicity. It also aimed to identify predictors of persistent spinal cord hyperexcitability. Pressure and cold pain thresholds, NFR responses (threshold and pain VAS) were prospectively measured in 62 participants at <3 weeks, 3 and 6 months post whiplash injury and in 22 healthy controls on two occasions a month apart. Pain levels and psychological distress (GHQ-28; IES) were measured at baseline. Whiplash participants were classified at 6 months post-injury using the Neck Disability Index: recovered (8%), mild pain and disability (10-28%) or moderate/severe pain and disability (30%). All whiplash groups demonstrated spinal cord hyperexcitability (lowered NFR thresholds) at 3 weeks post-injury. This hyperexcitability persisted in those with moderate/severe symptoms at 6 months but resolved in those who recovered or reported lesser symptoms at 6 months. In contrast generalized sensory hypersensitivity (pressure and cold) was only ever present in those with persistent moderate/severe symptoms and remained unchanged throughout the study period. This suggests different mechanisms underlie sensory hypersensitivity and NFR responses. In multivariate analyses only initial NDI scores (p=0.003) were a unique predictor of persistent spinal cord hyperexcitability indicating possible ongoing peripheral nociception following whiplash injury.

Magnetic resonance imaging findings of fatty infiltrate in the cervical flexors in chronic whiplash

STUDY DESIGN

Retrospective investigation of muscle changes in patients suffering from chronic whiplash-associated disorders (WAD).

OBJECTIVES

To quantitatively compare the presence of muscle alterations (fatty infiltrate [MFI] and cross-sectional area [CSA]) in the anterior musculature of the cervical spine in a cohort of chronic whiplash patients (WAD II) and healthy control subjects across muscle and cervical segmental level.

SUMMARY OF BACKGROUND DATA

Magnetic resonance imaging can be regarded as the gold standard for muscle imaging. There is little knowledge about in vivo features of anterior neck muscles in patients suffering from chronic WAD and how muscle structure differs across the factors of muscle, vertebral level, age, self-reported pain and disability, body mass index, and duration of symptoms.

METHODS

Reliable magnetic resonance imaging measures for MFI and CSA were performed for the anterior cervical muscles bilaterally in 109 female subjects (78 WAD, 31 healthy control; 18-45 years, 3 months to 3 years postinjury). The measures were performed on all subjects for the longus capitis and colli and the sternocleidomastoid muscles.

RESULTS

The WAD subjects had significantly larger MFI and CSA for the anterior muscles compared to healthy control subjects (all P < 0.0001). In addition, the amount of MFI varied by both cervical level and muscle, with the longus capitis/colli having the largest amount of fatty infiltrates at the C2-C3 level (P < 0.0001). MFI was inversely related to age, self-reported pain/disability, and body mass index but directly proportional to duration of symptoms.

CONCLUSION

There is significantly greater MFI and CSA in the anterior neck muscles, especially in the deeper longus capitis/colli muscles, in subjects with chronic WAD when compared to healthy controls. Future studies are required to investigate the relationships between muscular morphometry and symptoms in patients suffering from acute and chronic WAD.

What factors have influence on persistence of neck pain after a whiplash?

STUDY DESIGN

Prospective longitudinal study.

OBJECTIVE

To identify prognosis factors that allow us to identify patients with risk of developing chronic symptoms and disabilities after a whiplash injury.

SUMMARY OF BACKGROUND DATA

The prognosis factors for poor recovery in acute whiplash are not conclusive.

METHODS

We included 557 patients who suffered whiplash injury after road traffic accident and visited the Department of Physical Medicine and Rehabilitation of Mataró Hospital (Spain) for medical evaluation and rehabilitation treatment. The variables were collected following a protocol designed for the study, and all patients were assessed through the Visual Analogue Scale (VAS) for the intensity of neck pain, the Goldberg Depression and Anxiety Scale and the Northwick Park Neck Pain Questionnaire (NPH) for cervical column functionality at initial evaluation and 6 months later.

RESULTS

Factors related with VAS 6 months after the whiplash injury were women, age, number of days of cervical column immobilization, previous neck pain, self-employed workers, housewives, pensioners, students, presence of headache or dizziness, and VAS, Goldberg Depression and Anxiety scale, and NPH scores at initial evaluation. In multivaried analysis, it had been found that the variables that had influence on VAS 6 months after the whiplash injury were statistically significant for age, presence of dizziness, self-employed workers, and VAS and NPH scores at initial evaluation.

CONCLUSION

Our findings indicate that factors that allow us to identify patients at risk for poor recovery are age, dizziness, and initial evaluation of neck pain with VAS and cervical column functionality with NPH.

Functional outcome after road-crash injury: description of the ESPARR victims cohort and 6-month follow-up results

OBJECTIVE

It is essential to know about the long-term consequences of road crashes involving corporal injury in order to adopt relevant public health measures.

METHODS

The ESPARR cohort comprises 1168 road-crash victims, aged 16 or over, managed in hospitals in the Rhône administrative départment (France). It is based on the Registry of Road Traffic Casualties, which has been collecting exhaustive data since 1995. Two groups are monitored: mild to moderate (M-AIS 1 or 2) and severe (M-AIS > or =3). Patients were interviewed at the point of primary care, between 1 October 2004 and 31 July 2006. 6 months later, their state of health and presence of pain were compared. Multivariate analysis (logistic regression) was performed to identify factors related to residual pain.

RESULTS

Adults of the cohort were compared to the road crash population as a whole recorded over the same period in the same area. At 6 months post-accident, only 31.9% of victims deemed their health status to have entirely returned to normal; 63.8% of mild to moderate and 89.2% of severe cases reported residual pain, but neither pain frequency nor intensity correlated with M-AIS. Residual pain was related to lower limb injuries (OR=1.6; 95% CI=1.1-2.4). After adjustment, pain was essentially related to age, seriousness of the lesions and a stay in a rehabilitation unit.

CONCLUSION

The ESPARR cohort provides a unique opportunity in France to describe the trajectory of a road crash victim, in terms both of care and rehabilitation and of resumption of work and personal activity.

Minimizing the source of nociception and its concurrent effect on sensory hypersensitivity: an exploratory study in chronic whiplash patients

Background

The cervical zygapophyseal joints may be a primary source of pain in up to 60% of individuals with chronic whiplash associated disorders (WAD) and may be a contributing factor for peripheral and centrally mediated pain (sensory hypersensitivity). Sensory hypersensitivity has been associated with a poor prognosis. The purpose of the study was to determine if there is a change in measures indicative of sensory hypersensitivity in patients with chronic WAD grade II following a medial branch block (MBB) procedure in the cervical spine.

Methods

Measures of sensory hypersensitivity were taken via quantitative sensory testing (QST) consisting of pressure pain thresholds (PPT's) and cold pain thresholds (CPT's). In patients with chronic WAD (n = 18), the measures were taken at three sites bilaterally, pre- and post- MBB. Reduced pain thresholds at remote sites have been considered an indicator of central hypersensitivity. A healthy age and gender matched comparison group (n = 18) was measured at baseline. An independent t-test was applied to determine if there were any significant differences between the WAD and normative comparison groups at baseline with respect to cold pain and pressure pain thresholds. A dependent t-test was used to determine whether there were any significant differences between the pre and post intervention cold pain and pressure pain thresholds in the patients with chronic WAD.

Results

At baseline, PPT's were decreased at all three sites in the WAD group (p < 0.001). Cold pain thresholds were increased in the cervical spine in the WAD group (p < 0.001). Post-MBB, the WAD group showed significant increases in PPT's at all sites (p < 0.05), and significant decreases in CPT's at the cervical spine (p < 0.001).

Conclusions

The patients with chronic WAD showed evidence of widespread sensory hypersensitivity to mechanical and thermal stimuli. The WAD group revealed decreased sensory hypersensitivity following a decrease in their primary source of pain stemming from the cervical zygapophyseal joints.

Dry needling and exercise for chronic whiplash - a randomised controlled trial

Background

Chronic whiplash is a common and costly problem. Sensory hypersensitivity is a feature of chronic whiplash that is associated with poor responsiveness to physical treatments such as exercise. Modalities such as dry-needling have shown some capacity to modulate sensory hypersensitivity, suggesting that when combined with advice and exercise, such an approach may be more effective in the management of chronic whiplash. The primary aim of this project is to investigate the effectiveness of dry-needling, advice and exercise for chronic whiplash.

Method/Design

A double-blind randomised controlled trial will be conducted. 120 participants with chronic whiplash, grade II will be randomised to receive either 1) dry-needling, advice and exercise or 2) sham dry-needling, advice and exercise. All participants will receive an educational booklet on whiplash. Participants who are randomised to Group 1 will receive 6 treatments of combined dry-needling and exercise delivered in the first 3 weeks of the 6 week program, and 4 treatments of exercise only in the last 3 weeks of the program. Participants randomised to Group 2 will receive an identical protocol, except that a sham dry-needling technique will be used instead of dry-needling. The primary outcome measures are the Neck Disability Index (NDI) and participants' perceived recovery. Outcomes will be measured at 6, 12, 24 and 52 weeks after randomization by an assessor who is blind to the group allocation of the participants. In parallel, an economic analysis will be conducted.

Discussion

This trial will utilise high quality trial methodologies in accordance with CONSORT guidelines. The successful completion of this trial will provide evidence of the effectiveness and cost-effectiveness of a combined treatment approach for the management of chronic whiplash.

Trial registration

ACTRN12609000470291

Patients with chronic whiplash-associated disorders: relationship between clinical and psychological factors and functional health status

OBJECTIVES

To examine the relative contribution of cervical impairments and psychosocial factors to perceived disability among people with chronic whiplash-associated disorders.

DESIGN

A total of 86 patients with chronic whiplash-associated disorders participated in this observational, cross-sectional study. All patients were presented to outpatient physical therapy clinics. All patients completed the neck disability index. Depression, anxiety, and catastrophizing were measured with the Hospital Anxiety and Depression scale and the pain coping and cognition list, respectively. Cervical function was assessed by measuring the active range of motion. Stepwise and hierarchical regression analysis was used to estimate the contribution of cervical impairment and psychosocial functions to the variance in neck disability.

RESULTS

Depressive symptomatology and catastrophizing explained 61% of the variance in neck disability index scores. Catastrophizing explained 57% of the variance in neck disability index scores and 15% of the variance in the sum scores of active cervical rotations.

CONCLUSIONS

Catastrophizing explained the variance in both perceived neck disability and, to a lesser extent, active range of cervical motion, which suggests that pain-related catastrophizing plays an important role in the physical complaints of patients with chronic whiplash-associated disorders when referred to a physical therapist.

Cervical lateral glide increases nociceptive flexion reflex threshold but not pressure or thermal pain thresholds in chronic whiplash associated disorders: A pilot randomised controlled trial

Sensory hypersensitivity indicative of augmented central pain processing is a feature of chronic whiplash associated disorders (WAD). This study investigated the immediate effects of a cervical spine manual therapy (SMT) technique on measures of central hyperexcitability. In a randomised, single blind, clinical trial, 39 participants with chronic WAD were randomly assigned to a cervical SMT (lateral glide) or manual contact intervention. The Neck Disability Index (NDI) and GHQ-28 were administered at baseline. Pressure pain thresholds (PPTs), thermal pain thresholds (TPTs) and Nociceptive Flexion Reflex (NFR) responses (threshold and VAS of pain) were measured pre and post intervention. There was a significantly greater increase in NFR threshold following SMT compared to the manual contact intervention (p = 0.04). PPTs at the cervical spine increased following both SMT (mean +/- SE: 24.1 +/- 7.3%) and manual contact (21 +/- 8.4%) with no difference between interventions. There was no difference between interventions for pain ratings with the NFR test, PPTs at the Median Nerve or Tibialis Anterior, heat or cold TPT. SMT may be effective in reducing spinal hyperexcitability in chronic WAD.

A review of the definitions of 'recovery' used in prognostic studies on whiplash using an ICF framework

PURPOSE

The purpose of this article is to review the various definitions of recovery used in the prognostic whiplash literature to date, and to evaluate them from the framework of the International Classification of Functioning, Disability and Health (ICF).

METHODS

Reference lists of previous systematic reviews and meta-analyses on the topic were reviewed and citations were retrieved. An updated Medline search was performed. Recovery rates and the method for operationalising recovery were extracted and evaluated for their fit within the ICF model of health. Descriptive statistics were calculated and presented.

RESULTS

Thirty-one independent cohorts were identified. In total, 30 different primary methods for defining recovery were described in the sample of literature. Eighty-three percent of the primary outcomes fit within the body structure and function domain of the ICF. Restricted participation was the second most common domain represented, followed by activity limitations. Even within each domain, there is wide variability in the cut-off values for dichotomising a group as recovered or not.

CONCLUSIONS

The wide range of recovery rates reported in the literature can be at least partly accounted for by the lack of a standardised definition of recovery after acute whiplash. The emphasis on symptoms in the current literature neglects other important aspects of health as described by the ICF.

The clinical presentation of chronic whiplash and the relationship to findings of MRI fatty infiltrates in the cervical extensor musculature: a preliminary investigation

The objective was to determine whether any measurable changes in sensory responses, kinesthetic sense, cervical motion, and psychological features were related to established fatty infiltration values in the cervical extensor musculature in subjects with persistent whiplash. It is unknown if fatty infiltrate is related to any signs or symptoms. Data on motor function, Quantitative Sensory Testing, psychological and general well-being, and pain and disability were collected from 79 female subjects with chronic whiplash. Total fat values were created for all subjects by averaging the muscle fat indices by muscle, level, and side from our MRI dataset of all the cervical extensor muscles. Results of this study indicate the presence of altered physical, kinesthetic, sensory, and psychological features in this cohort of patients with chronic whiplash. Combined factors of sensory, physical, kinesthetic, and psychological features all contributed to a small extent in explaining the varying levels of fatty infiltrate, with cold pain thresholds having the most influence (r (2) = 0.28; P = 0.02). Identifying and relating quantifiable muscular alterations to clinical measures in the chronic state, underpin some clinical hypotheses for possible pathophysiological processes in this group with a chronic and recalcitrant whiplash disorder. Future research investigations aimed at accurate identification, sub-classification, prediction, and management of patients with acute and chronic whiplash is warranted and underway.

The effect of two exercise regimes; motor control versus endurance/strength training for patients with whiplash-associated disorders: a randomized controlled pilot study

Objective: To compare the effect of exercise regimes with focus on either motor control training or endurance/strength training for patients with whiplash-associated disorders in subacute phase.

Design: Randomized controlled trial.

Setting: An outpatient spine clinic in Norway.

Participants: Twenty-five subjects with a whiplash-associated disorder still having symptoms or disability six weeks after injury.

Interventions: The participants received 6—10 sessions of physiotherapy for six weeks with focus on either motor control or endurance and strength of neck muscles.

Measurements: The primary outcome measure was the Neck Disability Index. Secondary outcome measures were pain intensity, neck functioning and sick leave.

Results: No statistical significant differences concerning primary and secondary outcome measures were demonstrated between the groups. Approximately half of the participants in both groups obtained a clinically important change (improvement) on perceived disability assessed by Neck Disability Index at six weeks and one-year follow-up. The changes within both groups were statistically significant at six weeks, but not at one-year follow-up. For most pain-related variables clinical significant improvement was demonstrated in both groups at six weeks, but for fewer participants at one year. There was also statistical significant improvement within groups in some of the physical performance tests at one-year follow-up.

Conclusion: The changes associated with motor control training and endurance/ strength training of neck muscles were similar for reduced disability, pain and for improving physical performance. With a low number of participants and no control group, however, we cannot be sure whether the improvements are due to interventions or other reasons.

Short-term effects of cervical kinesio taping on pain and cervical range of motion in patients with acute whiplash injury: a randomized clinical trial

DESIGN

Randomized clinical trial.

OBJECTIVES

To determine the short-term effects of Kinesio Taping, applied to the cervical spine, on neck pain and cervical range of motion in individuals with acute whiplash-associated disorders (WADs).

BACKGROUND

Researchers have begun to investigate the effects of Kinesio Taping on different musculoskeletal conditions (eg, shoulder and trunk pain). Considering the demonstrated short-term effectiveness of Kinesio Tape for the management of shoulder pain, it is suggested that Kinesio Tape may also be beneficial in reducing pain associated with WAD.

METHODS AND MEASURES

Forty-one patients (21 females) were randomly assigned to 1 of 2 groups: the experimental group received Kinesio Taping to the cervical spine (applied with tension) and the placebo group received a sham Kinesio Taping application (applied without tension). Both neck pain (11-point numerical pain rating scale) and cervical range-of-motion data were collected at baseline, immediately after the Kinesio Tape application, and at a 24-hour follow-up by an assessor blinded to the treatment allocation of the patients. Mixed-model analyses of variance (ANOVAs) were used to examine the effects of the treatment on each outcome variable, with group as the between-subjects variable and time as the within-subjects variable. The primary analysis was the group-by-time interaction.

RESULTS

The group-by-time interaction for the 2-by-3 mixed-model ANOVA was statistically significant for pain as the dependent variable (F = 64.8; P<.001), indicating that patients receiving Kinesio Taping experienced a greater decrease in pain immediately postapplication and at the 24-hour follow-up (both, P<.001). The group-by-time interaction was also significant for all directions of cervical range of motion: flexion (F = 50.8; P<.001), extension (F = 50.7; P<.001), right (F = 39.5; P<.001) and left (F = 3.8, P<.05) lateral flexion, and right (F = 33.9, P<.001) and left (F = 39.5, P<.001) rotation. Patients in the experimental group obtained a greater improvement in range of motion than thosein the control group (all, P<.001).

CONCLUSIONS

Patients with acute WAD receiving an application of Kinesio Taping, applied with proper tension, exhibited statistically significant improvements immediately following application of the Kinesio Tape and at a 24-hour follow-up. However, the improvements in pain and cervical range of motion were small and may not be clinically meaningful. Future studies should investigate if Kinesio Taping provides enhanced outcomes when added to physical therapy interventions with proven efficacy or when applied over a longer period.

LEVEL OF EVIDENCE

Therapy, level 1b. J Orthop Sports Phys Ther 2009;39(7):515-521, Epub 24 February 2009. doi:10.2519/jospt.2009.3072.

Joint distraction magnitude is associated with different behavioral outcomes and substance P levels for cervical facet joint loading in the rat

The facet joint is a common source of pain in both the neck and low back, and can be injured by abnormal loading of the spinal joints. Whereas a host of nociceptive changes including neuronal activation, neuropeptide expression, and inflammatory mediator responses has been reported for rat models of joint pain, no such responses have been explicitly investigated or quantified for painful mechanical injury to the facet joint. Two magnitudes of joint loading were separately imposed in a rat model of cervical facet joint distraction: Painful and nonpainful distractions. Behavioral outcomes were defined by assessing mechanical hyperalgesia in the shoulders and forepaws. Substance P (SP) mRNA and protein levels were quantified in the dorsal root ganglion (DRG) and spinal cord at days 1 and 7 following distraction. Painful distraction produced mechanical hyperalgesia that was significantly greater (P < .010) than that for a nonpainful distraction. Painful distraction significantly increased spinal SP mRNA (P = .048) and SP protein expression in the DRG (P = .013) at day 7 compared to nonpainful distraction. However, spinal SP protein for painful distraction was significantly less (P = .024) than that for nonpainful distraction at day 1. Joint distractions producing different behavioral outcomes modulate SP mRNA and protein in the DRG and spinal cord, suggesting that SP responses may be involved with different temporal responses in painful joint loading.

PERSPECTIVE

SP mRNA and protein in the DRG and spinal cord are quantified at 2 time points after cervical facet joint distractions that separately do or do not produce mechanical hyperalgesia. Studies describe a role for SP to contribute to pain produced by mechanical joint loading.

Characterization of acute and chronic whiplash-associated disorders

SYNOPSIS

The development of chronic pain and disability following whiplash injury is common and contributes substantially to personal and economic costs related with this condition. Emerging evidence demonstrates the clinical presence of alterations in the sensory and motor systems, including psychological distress in all individuals with a whiplash injury, regardless of recovery. However, individuals who transition to the chronic state present with a more complex clinical picture characterized by the presence of widespread sensory hypersensitivity, as well as significant posttraumatic stress reactions. Based on the diversity of the signs and symptoms experienced by individuals with a whiplash condition, clinicians must take into account the more readily observable/measurable differences in motor, sensory, and psychological dysfunction. The implications for the assessment and management of this condition are discussed. Further review into the pathomechanical, pathoanatomical, and pathophysiological features of the condition also will be discussed.

LEVEL OF EVIDENCE

Level 5.J

Measurement properties of the neck disability index: a systematic review

STUDY DESIGN

Systematic review of clinical measurement.

OBJECTIVE

To find and synthesize evidence on the psychometric properties and usefulness of the neck disability index (NDI).

BACKGROUND

The NDI is the most commonly used outcome measure for neck pain, and a synthesis of knowledge should provide a deeper understanding of its use and limitations.

METHODS AND MEASURES

Using a standard search strategy (1966 to September 2008) and 4 databases (Medline, CINAHL, Embase, and PsychInfo), a structured search was conducted and supplemented by web and hand searching. In total, 37 published primary studies, 3 reviews, and 1 in-press paper were analyzed. Pairs of raters conducted data extraction and critical appraisal using structured tools. Ranking of quality and descriptive synthesis were performed.

RESULTS

Horizon estimation suggested the potential for 1 missed paper. The agreement between raters on quality assessments was high(kappa = 0.82). Half of the studies reached a quality level greater than 70%. Failures to report clear psychometric objectives/hypotheses or to rationalize the sample size were the most common design flaws. Studies often focused on less clinically applicable properties, like construct validity or group reliability, than transferable data, like known group differences or absolute reliability (standard error of measurement [SEM] or minimum detectable change [MDC]). Most studies suggest that the NDI has acceptable reliability, although intraclass correlation coefficients (ICCs) range from 0.50 to 0.98. Longer test intervals and the definition of stable can influence reliability estimates. A number of high-quality published (Korean, Dutch, Spanish, French, Brazilian Portuguese) and commercially supported translations are available. The NDI is considered a 1-dimensional measure that can be interpreted as an interval scale. Some studies question these assumptions. The MDC is around 5/50 for uncomplicated neck pain and up to 10/50 for cervical radiculopathy. The reported clinically important difference (CID) is inconsistent across different studies ranging from 5/50 to 19/50. The NDI is strongly correlated (>0.70) to a number of similar indices and moderately related to both physical and mental aspects of general health.

CONCLUSION

The NDI has sufficient support and usefulness to retain its current status as the most commonly used self-report measure for neck pain. More studies of CID in different clinical populations and the relationship to subjective/work/function categories are required.

Developing biologically-based assessment tools for physical therapy management of neck pain

SYNOPSIS

Neck pain is a common and episodic condition that is treated using a spectrum of interventions known to be moderately effective but is associated with a significant incidence of chronic pain. Recently, there has been increased focus on defining biological aspects of neck pain. Studies have indicated that neurophysiological, biomechanical, and motor control abnormalities are present and may be useful either in prognosis or classification. We review some of these findings in the context of our own work defining biological markers that may form the basis for clinical tests that can be used for prognosis, classification, or outcome evaluation in patients with neck pain. We have identified abnormalities in neurophysiology using quantitative sensory testing (vibration, touch, and current perception) and response to cold provocation that are related to neck disability. We have identified altered muscle biochemistry by measuring circulating muscle proteins in a lumbar surgery model and are now applying those methods to whiplash injury. We have incorporated capnography into treatment to address central physiological changes present in some patients by monitoring and training CO2 levels. We have developed an innovative new test, the Neck Walk Index, that captures abnormal control of head movement during slow gait as a means of differentiating patients with neck pain from either unaffected controls or individuals with other pathologies. We have used time-varying 3-dimensional joint orientation kinematics to assess deficits in motor control during an upper extremity reach task, the results showing that poor coordination and control of the shoulder girdle leads to shoulder guarding and inconsistencies in elbow joint movement. Despite some promising early results, future research is needed to determine how these measures help clinicians to diagnose, evaluate, and forecast future outcome for patients who present with neck pain.

LEVEL OF EVIDENCE

Diagnosis, level 5.

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.

Does expecting mean achieving? The association between expecting to return to work and recovery in whiplash associated disorders: a population-based prospective cohort study

To determine the association between expectations to return to work and self-assessed recovery. Positive expectations predict better outcomes in many health conditions, but to date the relationship between expecting to return to work after traffic-related whiplash-associated disorders and actual recovery has not been reported. We assessed early expectations for return to work in a cohort of 2,335 individuals with traffic-related whiplash injury to the neck. Using multivariable Cox proportional hazard analysis we assessed the association between return to work expectations and self-perceived recovery during the first year following the event. After adjusting for the effects of sociodemographic characteristics, initial pain and symptoms, post-crash mood, prior health status and collision-related factors, those who expected to return to work reported global recovery 42% more quickly than those who did not have positive expectations (HRR = 1.42, 95% CI 1.26-1.60). Knowledge of return to work expectation provides an important prognostic tool to clinicians for recovery.

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.

Maximal voluntary isometric neck strength deficits in adults with whiplash-associated disorders and association with pain and fear of movement

STUDY DESIGN

Controlled laboratory study using a cross-sectional, repeated-measures design.

OBJECTIVES

To quantify maximal voluntary isometric neck forces in healthy subjects and individuals with whiplash-associated disorder (WAD), using an objective measurement system to evaluate the test-retest properties of these strength measurements and to assess the links between neck strength, pain, kinesiophobia, and catastrophizing in patients with WAD.

BACKGROUND

The prognosis of WAD is difficult to predict due to a lack of objective measurement methods and to our limited understanding of the role of psychological factors in the development of chronic WAD symptoms.

METHODS AND MEASURES

Fourteen subjects with chronic WAD grade I or II and an age-matched, healthy group (n = 28) participated in this study. Cervical strength was measured with the Multi-Cervical Unit (MCU) in 6 directions, and pain was measured with a visual analog scale. Individuals in the WAD group completed the Neck Disability Index (NDI), the Tampa Scale for Kinesiophobia (TSK), and the Pain Catastrophizing Scale (PCS).

RESULTS

Significant deficits in strength were observed for the individuals in the WAD group compared to the healthy group, particularly in extension, retraction, and left lateral flexion (P<.05). The MCU demonstrated good intratester reliability for the healthy group (ICC = 0.80-0.92) and the WAD group (ICC = 0.85-0.98), and small standard errors of measurement for both groups. No significant association was found between neck strength and NDI, TSK, and PCS.

CONCLUSION

The MCU demonstrated good test-retest properties for healthy subjects and individuals with WAD. Cervical strength was lower in individuals with WAD; however, the strength deficits were not clearly linked with psychological factors.

A diagnosis-based clinical decision rule for spinal pain part 2: review of the literature

Background

Spinal pain is a common and often disabling problem. The research on various treatments for spinal pain has, for the most part, suggested that while several interventions have demonstrated mild to moderate short-term benefit, no single treatment has a major impact on either pain or disability. There is great need for more accurate diagnosis in patients with spinal pain. In a previous paper, the theoretical model of a diagnosis-based clinical decision rule was presented. The approach is designed to provide the clinician with a strategy for arriving at a specific working diagnosis from which treatment decisions can be made. It is based on three questions of diagnosis. In the current paper, the literature on the reliability and validity of the assessment procedures that are included in the diagnosis-based clinical decision rule is presented.

Methods

The databases of Medline, Cinahl, Embase and MANTIS were searched for studies that evaluated the reliability and validity of clinic-based diagnostic procedures for patients with spinal pain that have relevance for questions 2 (which investigates characteristics of the pain source) and 3 (which investigates perpetuating factors of the pain experience). In addition, the reference list of identified papers and authors' libraries were searched.

Results

A total of 1769 articles were retrieved, of which 138 were deemed relevant. Fifty-one studies related to reliability and 76 related to validity. One study evaluated both reliability and validity.

Conclusion

Regarding some aspects of the DBCDR, there are a number of studies that allow the clinician to have a reasonable degree of confidence in his or her findings. This is particularly true for centralization signs, neurodynamic signs and psychological perpetuating factors. There are other aspects of the DBCDR in which a lesser degree of confidence is warranted, and in which further research is needed.

From acute musculoskeletal pain to chronic widespread pain and fibromyalgia: application of pain neurophysiology in manual therapy practice

During the past decade, scientific research has provided new insight into the development from an acute, localised musculoskeletal disorder towards chronic widespread pain/fibromyalgia (FM). Chronic widespread pain/FM is characterised by sensitisation of central pain pathways. An in-depth review of basic and clinical research was performed to design a theoretical framework for manual therapy in these patients. It is explained that manual therapy might be able to influence the process of chronicity in three different ways. (I) In order to prevent chronicity in (sub)acute musculoskeletal disorders, it seems crucial to limit the time course of afferent stimulation of peripheral nociceptors. (II) In the case of chronic widespread pain and established sensitisation of central pain pathways, relatively minor injuries/trauma at any locations are likely to sustain the process of central sensitisation and should be treated appropriately with manual therapy accounting for the decreased sensory threshold. Inappropriate pain beliefs should be addressed and exercise interventions should account for the process of central sensitisation. (III) However, manual therapists ignoring the processes involved in the development and maintenance of chronic widespread pain/FM may cause more harm then benefit to the patient by triggering or sustaining central sensitisation.

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.