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

Higher initial levels of pain and disability, older age, cold hyperalgesia, impaired sympathetic vasoconstriction and moderate post-traumatic stress symptoms have been shown to be associated with poor outcome 6 months following whiplash injury. This study prospectively investigated the predictive capacity of these variables at a long-term follow-up. Sixty-five of an initial cohort of 76 acutely injured whiplash participants were followed to 2-3 years post-accident. Motor function (ROM; kinaesthetic sense; activity of the superficial neck flexors (EMG) during cranio-cervical flexion), quantitative sensory testing (pressure, thermal pain thresholds and brachial plexus provocation test), sympathetic vasoconstrictor responses and psychological distress (GHQ-28, TSK and IES) were measured. The outcome measure was Neck Disability Index (NDI) scores. Participants with ongoing moderate/severe symptoms at 2-3 years continued to manifest decreased ROM, increased EMG during cranio-cervical flexion, sensory hypersensitivity and elevated levels of psychological distress when compared to recovered participants and those with milder symptoms. The latter two groups showed only persistent deficits in cervical muscle recruitment patterns. Higher initial NDI scores (OR 1.00-1.1), older age (OR 1.00-1.13), cold hyperalgesia (OR 1.1-1.13) and post-traumatic stress symptoms (OR 1.03-1.2) remained significant predictors of poor outcome at long-term follow-up (r2=0.56). The robustness of these physical and psychological factors suggests that their assessment in the acute stage following whiplash injury will be important.     

Sensory hypersensitivity occurs soon after whiplash injury and is associated with poor recovery

Hypersensitivity to a variety of sensory stimuli is a feature of persistent whiplash associated disorders (WAD). However, little is known about sensory disturbances from the time of injury until transition to either recovery or symptom persistence. Quantitative sensory testing (pressure and thermal pain thresholds, the brachial plexus provocation test), the sympathetic vasoconstrictor reflex and psychological distress (GHQ-28) were prospectively measured in 76 whiplash subjects within 1 month of injury and then 2, 3 and 6 months post-injury. Subjects were classified at 6 months post-injury using scores on the Neck Disability Index: recovered (<8), mild pain and disability (10-28) or moderate/severe pain and disability (>30). Sensory and sympathetic nervous system tests were also measured in 20 control subjects. All whiplash groups demonstrated local mechanical hyperalgesia in the cervical spine at 1 month post-injury. This hyperalgesia persisted in those with moderate/severe symptoms at 6 months but resolved by 2 months in those who had recovered or reported persistent mild symptoms. Only those with persistent moderate/severe symptoms at 6 months demonstrated generalised hypersensitivity to all sensory tests. These changes occurred within 1 month of injury and remained unchanged throughout the study period. Whilst no significant group differences were evident for the sympathetic vasoconstrictor response, the moderate/severe group showed a tendency for diminished sympathetic reactivity. GHQ-28 scores of the moderate/severe group were higher than those of the other two groups. The differences in GHQ-28 did not impact on any of the sensory measures. These findings suggest that those with persistent moderate/severe symptoms at 6 months display, soon after injury, generalised hypersensitivity suggestive of changes in central pain processing mechanisms. This phenomenon did not occur in those who recover or those with persistent mild symptoms.     

The development of psychological changes following whiplash injury

Psychological distress is a feature of chronic whiplash-associated disorders, but little is known of psychological changes from soon after injury to either recovery or symptom persistence. This study prospectively measured psychological distress (General Health Questionnaire 28, GHQ-28), fear of movement/re-injury (TAMPA Scale of Kinesphobia, TSK), acute post-traumatic stress (Impact of Events Scale, IES) and general health and well being (Short Form 36, SF-36) in 76 whiplash subjects within 1 month of injury and then 2, 3 and 6 months post-injury. Subjects were classified at 6 months post-injury using scores on the Neck Disability Index: recovered (<8), mild pain and disability (10-28) or moderate/severe pain and disability (>30). All whiplash groups demonstrated psychological distress (GHQ-28, SF-36) to some extent at 1 month post-injury. Scores of the recovered group and those with persistent mild symptoms returned to levels regarded as normal by 2 months post-injury, parallelling a decrease in reported pain and disability. Scores on both these tests remained above threshold levels in those with ongoing moderate/severe symptoms. The moderate/severe and mild groups showed elevated TSK scores at 1 month post-injury. TSK scores decreased by 2 months in the group with residual mild symptoms and by 6 months in those with persistent moderate/severe symptoms. Elevated IES scores, indicative of a moderate post-traumatic stress reaction, were unique to the group with moderate/severe symptoms. The results of this study demonstrated that all those experiencing whiplash injury display initial psychological distress that decreased in those whose symptoms subside. Whiplash participants who reported persistent moderate/severe symptoms at 6 months continue to be psychologically distressed and are also characterised by a moderate post-traumatic stress reaction.     

Assessment and validation of prognostic models for poor functional recovery 12 months after whiplash injury: a multicentre inception cohort study

Uncertainty surrounds prognostic factors after whiplash injury. Previously we identified a prognostic model for 6-month pain-related disability in a cohort of 80 participants with acute whiplash. Predictors included initial disability, older age, decreased cold pain thresholds, decreased neck rotation movement, posttraumatic stress symptoms and decreased sympathetic vasoconstriction. The objective of this study was to externally validate this model. In a multicentre inception cohort study, 286 participants with acute whiplash (I, II or III) were assessed at <3 weeks and 12 months after injury. The Neck Disability Index (NDI) was the outcome. Observed and predicted NDI scores were generated using the published equation of the original model. Model discrimination between participants with no or mild disability from those with moderate to severe disability was examined by receiver operating characteristic curves. Initial NDI and cold pain threshold predicted current observed 12-month NDI scores (r(2) = 0.50, 95% confidence interval 0.42 to 0.58). There was a significant site effect, and the estimated marginal mean ± SE of 12-month NDI for Iceland (27.6 ± 1.79%) was higher than the other 3 sites (Melbourne 11.2 ± 5.03%, Canada 16.4 ± 2.36%, Brisbane 16.8 ± 1.17%). After adjusting for site, age and Impact of Events Scale scores regained significance (r(2) = 0.56, 95% confidence interval 0.48 to 0.64). The tested model was not precise in predicting NDI as a continuous variable. However, it found good accuracy to discriminate participants with moderate to severe disability at 12 months (area under the receiver operating characteristic curve 0.89 [95% confidence interval 0.84-0.94], P<.001) which is clinically useful.     

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.     

Development of motor system dysfunction following whiplash injury

Dysfunction in the motor system is a feature of persistent whiplash associated disorders. Little is known about motor dysfunction in the early stages following injury and of its progress in those persons who recover and those who develop persistent symptoms. This study measured prospectively, motor system function (cervical range of movement (ROM), joint position error (JPE) and activity of the superficial neck flexors (EMG) during a test of cranio-cervical flexion) as well as a measure of fear of re-injury (TAMPA) in 66 whiplash subjects within 1 month of injury and then 2 and 3 months post injury. Subjects were classified at 3 months post injury using scores on the neck disability index: recovered (<8), mild pain and disability (10-28) or moderate/severe pain and disability (>30). Motor system function was also measured in 20 control subjects. All whiplash groups demonstrated decreased ROM and increased EMG (compared to controls) at 1 month post injury. This deficit persisted in the group with moderate/severe symptoms but returned to within normal limits in those who had recovered or reported persistent mild pain at 3 months. Increased EMG persisted for 3 months in all whiplash groups. Only the moderate/severe group showed greater JPE, within 1 month of injury, which remained unchanged at 3 months. TAMPA scores of the moderate/severe group were higher than those of the other two groups. The differences in TAMPA did not impact on ROM, EMG or JPE. This study identifies, for the first time, deficits in the motor system, as early as 1 month post whiplash injury, that persisted not only in those reporting moderate/severe symptoms at 3 months but also in subjects who recovered and those with persistent mild symptoms.     

Comparison of the relative benefits of 2 versus 10 days of soft collar cervical immobilization after acute whiplash injury

OBJECTIVE: To investigate the effects of 2-day and 10-day immobilization of the cervical spine on pain, range of motion (ROM), and disability of patients with Quebec Task Force (QTF) grade II whiplash injuries. DESIGN: Randomized controlled trial. SETTING: University hospital emergency department. PARTICIPANTS: Seventy patients with acute QTF grade II whiplash injuries. INTERVENTIONS: At the intake examination within 24 hours after the whiplash trauma, the patients were randomized to 2 therapy groups (2-d or 10-d immobilization with a soft cervical collar). All patients received pain drugs (nonsteroidal anti-inflammatory drugs) and after 7 days, all patients started a standardized physiotherapy program 2 to 3 times a week. MAIN OUTCOME MEASURES: Patients' pain and disability scores were assessed using visual analog scales and ROM was assessed using a goniometer. All parameters were measured within 24 hours after injury and after 2 and 6 months. RESULTS: After 2 months, the different periods of immobilization (2d or 10d) were associated with comparable improvements in pain symptoms (median, 4.60 vs 4.65), ROM (median, 100.0 degrees vs 117.5 degrees ), and disability score (median, 4.90 vs 5.15). No statistically significant differences could be identified between the 2 treatment groups. After 6 months, persistent pain was reported by 4 patients in each group (12.5%). CONCLUSIONS: In patients with QTF grade II whiplash injuries, there is no short- or long-term difference between 2-day and 10-day immobilization with a cervical collar in terms of pain, ROM, or disability.     

A neuropathic pain component is common in acute whiplash and associated with a more complex clinical presentation

Whiplash is a heterogeneous condition with some individuals showing features suggestive of neuropathic pain. This study investigated the presence of a neuropathic pain component in acute whiplash using the Self-reported Leeds Assessment of Neuropathic Signs and Symptoms' scale (S-LANSS) and evaluated relationships among S-LANSS responses, pain/disability, sensory characteristics (mechanical, thermal pain thresholds, and Brachial plexus provocation test (BPPT) responses) and psychological distress (General Health Questionnaire-28 (GHQ-28)). Participants were 85 people with acute whiplash (<4 weeks) (54 females, age 36.27+/-12.69 years). Thirty-four percent demonstrated a predominantly neuropathic pain component (S-LANSS>or=12). This group showed higher pain/disability, cold hyperalgesia, cervical mechanical hyperalgesia, and less elbow extension with the BPPT (p<0.03) when compared to the group with non-neuropathic pain (S-LANSS0.09). None of the S-LANSS items could discriminate those with cold hyperalgesia (p=0.06). A predominantly neuropathic pain component is related to a complex presentation of higher pain/disability and sensory hypersensitivity. The S-LANSS may be a useful tool and the BPPT a useful clinical test in the early assessment of whiplash.     

Self-rated disability,fear-avoidance beliefs,nonorganic pain behaviors are important mediators of ranges of active motion in chronic whiplash patients

Abstract

Purpose: The influence of self-rated disability and fear-avoidance beliefs on whiplash sufferers in their performance of active ranges of motion has not been studied well. We undertook a cross-sectional study to determine this. Methods: Chronic whiplash subjects completed a standard clinical examination. They completed the Neck Disability Index (NDI), the Tampa Scale for Kinesiophobia (TSK) and pain visual analog scale (VAS). Active ranges of motion (goniometer) and cervical nonorganic simulation signs (C-NOSS) were obtained by the examiner. Univariate and multivariable analyses were conducted on these scores. Results: Sixty-four subjects (37 female) with a mean age of 41.4 (SD 16.1) years completed all scores. NDI, pain VAS and C-NOSS correlated significantly with ROM. In a multivariable model, only the NDI score contributed significantly to the variance of the ROM scores (14%). Conclusion: As chronic whiplash sufferers perform ROM in a clinical examination, these ranges are importantly influenced by their self-perceived disability. Cervical nonorganic simulation signs can be helpful in distinguishing high from very high levels of disability and motion restriction. The lack of correlation with the TSK may present a challenge to the Fear Avoidance Model in whiplash.

• Implications for Rehabilitation

• Self-ratings of disability in chronic whiplash sufferers are influenced by their fear-avoidance beliefs.

• While self-ratings of disability are known to predict chronicity of whiplash, there is less known about how these ratings affect impairment assessment during recovery.

• This study shows that self-ratings of disability influence the presentation of impairment by chronic whiplash sufferers with respect to their ranges of neck motion.

• Signs of nonorganic behavior also influence ranges of motion and self-ratings of disability.

• These findings should be incorporated into the interpretation of impairment findings in chronic whiplash sufferers in order to improve management.

     

Self-reported driving habits in subjects with persistent whiplash-associated disorder: relationship to sensorimotor and psychologic features

Pereira MJ, Jull GA, Treleaven JM. Self-reported driving habits in subjects with persistent whiplash-associated disorder: relationship to sensorimotor and psychologic features.

Objectives

To study self-reported driving habits after whiplash injury and to determine any relation among self-reported driving habits, selected sensorimotor impairments, and psychologic features.

Design

Repeated-measures, case-controlled.

Setting

Tertiary institution.

Participants

Subjects (n=30) with chronic whiplash and 30 asymptomatic controls.

Interventions

Not applicable.

Main Outcome Measures

The Driving Habits Questionnaire (composite driving tasks score), Neck Disability Index (NDI), 28-item General Health Questionnaire (GHQ-28), Impact of Events Scale−Revised (IES-R), Tampa Scale for Kinesiophobia, cervical range of motion, cervical joint position error, and smooth pursuit neck torsion test.

Results

Subjects in the whiplash group had equal driving exposure and driving spaces (distances, locations) compared with control subjects but reported significantly more driving difficulty with most driving tasks (P<.01). There were no significant correlations between the composite driving tasks score and any of the sensorimotor impairments, but there were significant and moderate correlations between the composite driving task score and both pain and disability (NDI score, .518) and anxiety (GHQ-28 score, .518; IES-R score, .524).

Conclusions

Persons with chronic whiplash have greater self-reported driving difficulty than controls, which appears to relate more to reported levels of pain and disability and psychologic stress than laboratory measures of features of cervical sensorimotor control.     

Compensation claim lodgement and health outcome developmental trajectories following whiplash injury: A prospective study

This study aimed to identify distinctive trajectories for pain/disability and posttraumatic stress disorder (PTSD) symptoms following whiplash injury and to examine the effect of injury compensation claim lodgement on the trajectories. In a prospective study, 155 individuals with whiplash were assessed at <1 month, 3, 6 and 12 months post injury. Outcomes at each time point were Neck Disability Index (NDI) and the Posttraumatic Stress Diagnostic Scale (PDS). Group-based trajectory analytical techniques were used to identify outcome profiles. The analyses were then repeated after including third party compensation claim lodgment as a binary time-changing covariate. Three distinct NDI trajectories were determined: (1) Mild: mild or negligible pain/disability for the entire 12 months (45%), (2) Moderate: initial moderate pain/disability that decreased to mild levels by 3 months (39%) and (3) Chronic-severe: severe pain/disability persisting at moderate/severe levels for 12 months (16%). Three distinct PTSD trajectories were also identified: (1) Resilient: mild symptoms throughout (40%), (2) Recovering: initial moderate symptoms declining to mild levels by 3 months (43%) and (3) Chronic moderate-severe: persistent moderate/severe symptoms throughout 12 months (17%). Claim submission had a detrimental effect on all trajectories (p < 0.001) except for the Chronic-severe NDI trajectory (p = 0.098). Following whiplash injury, there are distinct pathways of recovery for pain/ disability and PTSD symptoms. Management of whiplash should consider the detrimental association of compensation claim with psychological recovery and recovery of those with mild to moderate pain/disability levels. However, claim lodgement has no significant association with a more severe pain and disability trajectory.     

Psychologic factors are related to some sensory pain thresholds but not nociceptive flexion reflex threshold in chronic whiplash

OBJECTIVES: Sensory hypersensitivity, central hyperexcitability [lowered nociceptive flexion reflex (NFR) thresholds], and psychologic distress are features of chronic whiplash. However, relationships between these substrates are not clear. This study tested the hypothesis that psychologic distress and catastrophization are correlated with sensory hypersensitivity and NFR responses in chronic whiplash. METHODS: Pressure and thermal pain thresholds (mean values across 3 body sites), NFR threshold, and pain at threshold Visual Analog Scale were measured in 30 participants with chronic whiplash and 30 asymptomatic controls. Pain and disability levels Neck Disability Index, psychologic distress (GHQ-28), and catastrophization (PCS) were also measured in the whiplash group. RESULTS: Whiplash injured participants demonstrated lowered pain thresholds to pressure and cold (P<0.05); lowered NFR thresholds (P=0.003), and demonstrated above threshold levels of psychologic distress (GHQ-28) and levels of catastrophization comparable with other musculoskeletal conditions. There were no group differences for heat pain thresholds or pain at NFR threshold. In the whiplash group, PCS scores correlated moderately with cold pain threshold (r=0.51, P=0.01). In contrast, there were no significant correlations between GHQ-28 scores and pain threshold measures or between psychologic factors and NFR responses in whiplash participants. There were no significant correlations between psychologic factors and pain thresholds or NFR responses in controls. DISCUSSION: We have demonstrated that psychologic factors have some association with sensory hypersensitivity (cold pain threshold measures) in chronic whiplash but do not seem to influence spinal cord excitability. This suggests that psychologic disorders are important, but not the only, determinants of central hypersensitivity in whiplash patients.     

Reduced cold pressor pain tolerance in non-recovered whiplash patients: a 1-year prospective study.

Whiplash injury and chronic whiplash syndrome represent major health problems in certain western communities, pain being the main symptom. Sensitization of the nociceptive system may play a role for non-recovery after whiplash injury. AIMS: This study examined if tolerance to endure pain stimuli may predict outcome in whiplash injury. In a prospective fashion, 141 acute whiplash patients exposed to rear-end car collision (WAD grade 1-3) and 40 ankle-injured controls were followed and exposed to a cold pressor test, respectively, 1 week, 1, 3, 6 and 12 months after the injury. VAS score of pain and discomfort was obtained before, during and after immersion of the dominant hand into cold water for 2 min. The McGill Pain Questionnaire showed that ankle-injured controls had higher initial pain scores than the corresponding whiplash group, while whiplash-injured subjects had higher scores at 6 months; pain scores being similar at other time points. No difference was found in cold pressor pain between recovered whiplash patients and ankle-injured subjects. Non-recovery was only encountered in whiplash injury. Eleven non-recovered whiplash patients (defined as: handicap after 1 year) showed reduced time to peak pain from 1 week to 3 months (P<0.001), 6 months (P<0.01), but not 12 months after the injury. A larger pain area was seen in non-recovered vs. recovered whiplash-injured subjects during the entire observation period (P<0.001). Non-recovery after whiplash was associated with initially reduced cold pressor pain endurance and increased peak pain, suggesting that dysfunction of central pain modulating control systems plays a role in chronic pain after acute whiplash injury.     

Derivation of a clinical prediction rule to identify both chronic moderate/severe disability and full recovery following whiplash injury

Recovery following a whiplash injury is varied: approximately 50% of individuals fully recover, 25% develop persistent moderate/severe pain and disability, and 25% experience milder levels of disability. Identification of individuals likely to develop moderate/severe disability or to fully recover may help direct therapeutic resources and optimise treatment. A clinical prediction rule (CPR) is a research-generated tool used to predict outcomes such as likelihood of developing moderate/severe disability or experiencing full recovery from whiplash injury. The purpose of this study was to assess the plausibility of developing a CPR. Participants from 2 prospective, longitudinal studies that examined prognostic factors for poor functional recovery following whiplash injury were used to derive this tool. Eight factors, previously identified as predictor variables of poor recovery, were included in the analyses: initial neck disability index (NDI), initial neck pain (visual analogue scale), cold pain threshold, range of neck movement, age, gender, presence of headache, and posttraumatic stress symptoms (Posttraumatic Diagnostic Scale [PDS]). An increased probability of developing chronic moderate/severe disability was predicted in the presence of older age and initially higher levels of NDI and hyperarousal symptoms (PDS) (positive predictive value [PPV] = 71%). The probability of full recovery was increased in younger individuals with initially lower levels of neck disability (PPV = 71%). This study provides initial evidence for a CPR to predict both chronic moderate/severe disability and full recovery following a whiplash injury. Further research is needed to validate the tool, determine the acceptability of the proposed CPR by practitioners, and assess the impact of inclusion in practice.     

Similar factors predict disability and posttraumatic stress disorder trajectories after whiplash injury

Distinct developmental trajectories for neck disability and posttraumatic stress disorder (PTSD) symptoms after whiplash injury have recently been identified. This study aimed to identify baseline predictors of membership to these trajectories and to explore their dual development. In a prospective study, 155 individuals with whiplash were assessed at <1 month, 3, 6, and 12 months postinjury. Outcomes at each time point were assessed according to the Neck Disability Index and the Posttraumatic Stress Diagnostic Scale. Baseline predictor variables were age, gender, initial pain (based on a visual analogue scale [VAS]), pressure pain thresholds (PPT), cold pain thresholds (CPT), and sympathetic vasoconstrictor responses. Group-based trajectory analytical techniques were used to parameterise the optimal trajectories and to identify baseline predictors. A dual trajectory analysis was used to explore probabilities of conditional and joint trajectory group membership. CPT ? 13°C (OR = 26.320, 95% CI = 4.981-139.09), initial pain level (VAS) (OR = 4.3, 95% CI = 4.98-139.1), and age (OR = 1.109, 95% CI = 1.043-1.180) predicted a chronic/severe disability trajectory. The same baseline factors also predicted chronic moderate/severe PTSD (CPT ? 13°C, OR = 9.7, 95%CI = 2.22-42.44; initial pain level [VAS]: OR = 2.13, 95% CI = 1.43-3.17; age: OR = 1.07, 95% CI = 1.01-1.14). There was good correspondence of trajectory group for both disability and PTSD. These findings support the proposal of links between the development of chronic neck related disability and PTSD after whiplash injury.     

Hypoaesthesia occurs with sensory hypersensitivity in chronic whiplash--further evidence of a neuropathic condition

Hypersensitivity to a variety of stimuli has been shown in whiplash associated disorders and may be indicative of peripheral nerve involvement. This cross-sectional study utilised Quantitative sensory testing (QST) including vibration, thermal, electrical detection thresholds as an indirect measure of primary afferents that mediate innocuous and painful sensation. Pain thresholds and psychological distress (SCL-90-R) were also measured. Thirty-one subjects with chronic whiplash (>3 months, NDI: 49+/-17) and 31 controls participated. The whiplash group demonstrated elevated vibration, heat and electrical detection thresholds at most hand sites compared to controls (p<0.05). Electrical detection thresholds in the lower limb were no different from controls (p=0.83). Mechanical and cold pain thresholds were lower in the whiplash group (p<0.05) with no group difference in heat pain thresholds (p>0.1). SCL-90 scores were higher in the whiplash group but did not impact on any of the sensory measures. A combination of pain threshold and detection measures best predicted the whiplash group. Sensory hypoaesthesia and hypersensitivity co-exist in the chronic whiplash condition. These findings may indicate peripheral afferent nerve fibre involvement but could be a further manifestation of disordered central pain processing.     

Pain,perceived injustice and the persistence of post-traumatic stress symptoms during the course of rehabilitation for whiplash injuries

The present study assessed the role of pain and pain-related psychological variables in the persistence of post-traumatic stress symptoms following whiplash injury. Individuals (N = 112) with whiplash injuries who had been admitted to a standardized multidisciplinary rehabilitation program were asked to complete measures of pain, post-traumatic stress symptoms, physical function and pain-related psychological variables at three different points during their treatment program. The findings are consistent with previous research showing that indicators of injury severity such as pain, reduced function and disability, and scores on pain-related psychological were associated with more severe post-traumatic stress symptoms in individuals with whiplash injuries. Contrary to expectations, indicators of pain severity did not contribute to the persistence of post-traumatic stress symptoms. Univariate analyses revealed that self-reported disability, pain catastrophizing and perceived injustice were significant determinants of the persistence of post-traumatic stress symptoms. In multivariate analyses, only perceived injustice emerged as a unique predictor of the persistence of post-traumatic stress symptoms. The results suggest that early adequate management of pain symptoms and disability consequent to whiplash injury might reduce the severity of post-traumatic stress symptoms. The development of effective intervention techniques for targeting perceptions of injustice might be important for promoting recovery of post-traumatic stress symptoms consequent to whiplash injury.     

Responses to a clinical test of mechanical provocation of nerve tissue in whiplash associated disorder

Involvement of nerve tissue may contribute to the persistence of pain following a whiplash injury. This study aimed to investigate responses to the brachial plexus provocation test (BPPT) in 156 subjects with chronic whiplash associated disorder (WAD) with and without associated arm pain and 95 asymptomatic control subjects. The range of elbow extension (ROM) and visual analogue scale (VAS) pain scores were measured. Subjects with chronic WAD demonstrated significantly less ROM and higher VAS scores with the BPPT than the asymptomatic subjects (P<0.001). These effects occurred bilaterally. Within the whiplash population, subjects whose arm pain was reproduced by the BPPT demonstrated significantly less ROM on both the symptomatic and asymptomatic sides when compared to the whiplash subjects whose arm pain was not reproduced by the BPPT (P=0.003) and significantly less ROM and higher VAS scores than those whiplash subjects with no arm pain (P=0.003, 0.01). Only the whiplash subjects whose arm pain was reproduced by the BPPT demonstrated differences between the symptomatic and asymptomatic sides. These generalized hyperalgesic responses to the BPPT support the hypothesis of central nervous system hypersensitivity as contributing to persistent pain experienced by WAD patients.     

Measurement of cervical flexor endurance following whiplash

AIM: To investigate measurement properties of a practical test of cervical flexor endurance (CFE) in whiplash patients including inter-rater reliability, sensitivity to clinical change, criterion related validity against the Neck Disability Index (NDI), and discriminant validity for injured versus uninjured populations. METHODS: Two samples were recruited, 81 whiplash patients, and a convenience sample of 160 subjects who were not seeking treatment and met criteria for normal pain and range of motion. CFE was measured using a stopwatch while the subject, in crook lying, held their head against gravity to fatigue. RESULTS: Inter-rater reliability in whiplash patients was in a range considered 'almost perfect' (Intraclass Correlation=0.96). CFE had greater inter-subject variability than the NDI or range of motion in any of three planes. However, the effect size for improvement in CFE over treatment was as large as the effect sizes for all of those measures. In multivariate regression, CFE changes accounted for changes on the NDI better than the three ranges of motion. CFE discriminated whiplash patients who were within six months of injury (n=71) from age and gender matched normals with high effect size (ES=1.5). CONCLUSIONS: These findings provide evidence of reliability and validity for CFE measurement, and demonstrate that CFE detects clinical improvements. Variance on CFE emphasizes the need to consider inter-, and intra-subject standard deviations to interpret scores.     

Whiplash associated disorder: incidence and natural history over the first month for patients presenting to a UK emergency department

Objectives

To describe the epidemiology, process of care, and outcomes at 4–6 weeks after injury among patients with whiplash associated disorder attending a UK emergency department.

Methods

All patients presenting during the study period with neck pain following a road traffic accident who met the inclusion criteria were assessed. Patients were followed up with a telephone interview at 4–6 weeks after attendance using the Neck Disability Index (NDI). The patient''s general practitioner (GP) was contacted post attendance to ascertain subsequent healthcare use.

Results

A total of 200 patients were recruited to the study, of which 30 were lost to follow up. Four variables, midline tenderness (p = 0.008; 95% CI 0.9 to 6.1), x ray request (p = 0.004; 0.9 to 6.1), wearing a seat belt (p = 0.038; 0.2 to 6.2), and having seen their GP post injury (p = 0.001; CI −10.5 to 6.6), were found to be associated with a higher NDI score at follow up. Significant correlation was identified with a high pain score and an increasing age of patient and high NDI scores. No correlation was found between the impact speed, speed of vehicle struck, or time since incident with the NDI. Two thirds of patients had some disability at 4–6 weeks after injury; 91 patients (54.5%) saw their GP in the intervening period between attending the department and telephone follow up, and 87/170 patients had no idea about their prognosis.

Conclusions

This study identifies that there is significant disability associated with whiplash associated disorder. Clear prognostic information would be a useful development.