The Quebec classification and a new Swedish classification for whiplash-associated disorders in relation to life satisfaction in patients at high risk of chronic functional impairment and disability

A Review of the Clinical Utility of Therapeutic Facet Joint Injections in Whiplash Associated Cervical Spinal Pain

Background and Objective

Whiplash neck injury was described by Crowe in 1928. Whiplash-associated disorder (WAD) is defined as a cervical spinal injury following an acceleration-deceleration mechanism. It is a constellation of symptoms due to psychological factors and neural adaptations, with significant social costs.

Review Summary

There are multiple classification systems for WAD in the literature. The Quebec Classification is most reported and is predictive of the likelihood of progression to chronicity. The facet joint has been identified as a pain generator in 50% of cases. We outline the likely anatomical cause of WAD and summarize the protocol of medial branch block injections for diagnostic and therapeutic purposes, as well as the indications for and published results of facet joint ablation in WAD. We also highlight the development of ultrasound as an alternative to computed tomography or fluoroscopy for injection guidance.

Conclusions

WAD is a complex condition associated with sensory disturbance, pain, motor chronic pain, and psychological distress. The literature supports a single diagnostic medial branch block followed by a therapeutic facet joint ablation for chronic pain. WAD should be managed in a multidisciplinary fashion, with an early involvement of psychological specialists when required.

A risk stratification tool for prehospital triage of patients exposed to a whiplash trauma

OBJECTIVE

Our aim was to develop a risk stratification model to predict the presence of a potentially more sinister injury in patients exposed to a whiplash trauma.

METHODS

The study base comprised of 3,115 residents who first sought healthcare contact within one week after being exposed to a whiplash trauma between 1999-2008, from within a defined geographical area, Skaraborg County in south-western Sweden. Information about gender, age, time elapsed prior to seeking care, type of health care contact, and hospitalisation was retrieved. Seventeen potential risk factors were identified and evaluated using multivariable logistic regression.

RESULTS

Of 3,115 patients, 215 (6.9%) required hospital admission so theoretically 93% could have been initially assessed by primary health care. However, only 46% had their first contact in primary health care. All patients had symptoms resulting in a diagnosis of whiplash injury. Four risk factors were found to be associated with hospital admission: commotio cerebri (OR 31, 19-51), fracture / luxation (OR 11, 5.1-22), serious injury (OR 41, 8.0-210), and the patient sought care during the same day as the trauma (OR 5.9, 3.7-9.5). These four risk factors explained 27% of the variation for hospital admission and the area under curve (AUC) was 0.77 (0.74-0.80). Ninety-six percent of patients (2,985) had only a whiplash injury with no other injury. These could be split into those attending health care the same day as the trauma, 1,737 (56%) with a 7.1% risk for hospital admission, and those attending health care later, 1,248 (40%) with a 1.3% risk for hospital admission.

CONCLUSION

Patients with no signs of commotio cerebri, no fracture/luxation injury, no serious injury, comprising 96% of all patients exposed to a whiplash trauma can initially be referred to primary health care for initial assessment. However, those contacting the health care the same day as the trauma should be referred to a hospital for evaluation if they can't get an appointment with a general practitioner the same day.

Gender differences in care-seeking behavior and healthcare consumption immediately after whiplash trauma

OBJECTIVE

The aim was to study gender differences in care-seeking behavior and treatment provided immediately after whiplash trauma.

METHODS

Participants were residents from a defined geographical area, Skaraborg County in the southwestern part of Sweden. A cohort of 3,368 persons exposed to whiplash trauma and attending a healthcare facility immediately after the trauma between 1999 and 2008 were identified in a database. Information about gender, age, time elapsed prior to seeking care, type of healthcare contact, initial treatment provided and eventual hospitalization time was retrieved.

RESULTS

Women sought care later than men (p = 0.00074). Women consulted primary healthcare first more often than men, who more often first sought hospital care (p = 0.0060). There were no gender differences regarding the type of treatment after trauma. Women had longer hospital admission than men (p = 0.022), indicating their injuries were at least similar to or worse than men's.

CONCLUSION

Women sought healthcare later than men after whiplash trauma. Although not directly investigated in this study, it raises the question if this may reduce their probability of getting financial compensation compared to men.

Whiplash Associated Disorders (WAD): Responses to pharmacological challenges and psychometric tests

Objectives The present study challenges chronic Whiplash Associated Disorders (WAD)-subjects to a pharmacological intravenous (i.v.) test with morphine, ketamine, and active placebo (midazolam). The aim was to describe the short-term responses to drugs and the assumed heterogeneity in the patterns of responses. We related the different responder groups to the results from psychometric tests. Methods The study includes 95 patients, all with chronic WAD and referred to our departments. They answered a questionnaire including the following psychometric instruments relevant for chronic pain: Beck Depression Inventory, Coping Strategies Questionnaire, Multidimensional Pain Inventory, Life Satisfaction Checklist, SF36 and EuroQol. The subjects also went through sessions with separate infusions of morphine (0.3 mg/kg), ketamine (0.3 mg/kg) and midazolam (0.05 mg/kg). Infusion time was 30 min followed by a 2-h post-infusion assessment. Assessments were made using a Visual Analogue Scale (VAS) for pain intensity and unpleasantness and by statements of per cent pain relieved. A categorical pain rating scale was also used. A positive response was defined as ≥50% decrease of the VAS-level on two consecutive assessment points during the test sessions, anything less was a non response. The placebo responders were defined as those with a positive response to the active placebo infusion. Results The tests were completed by 94 subjects and 26% of these were placebo responders. Among the placebo non responders, 47% responded to morphine, 41% to ketamine, 25% to both drugs and 37% to neither morphine nor ketamine (pain intensity assessments). Similar proportions were found in the assessments of pain unpleasantness and per cent pain relieved. Approximately one in four subjects (27%, pain intensity assessment) did not respond to any of the drugs tested. This relatively high proportion of non responders seemed to be worst cases in some aspects of the psychometric tests. Generally, this non responder group had a trend to score worse for most items in the psychometric tests with some reaching significance in a univariate analysis. This result was confirmed in a multivariate context, although the results indicated only small differences between the groups. All three substances showed significant pain relief compared to baseline on all assessment points. On most variables, morphine and ketamine were significantly more effective compared to the active placebo. Conclusions There are different subgroups among subjects with chronic WAD with variations in responses to i.v. morphine, ketamine, and midazolam (active placebo). Subjects with chronic WAD who did not respond to any of the drugs tested scored badly in some aspects of the psychometric instruments. Implications The present study confirms one aspect of the heterogeneity in the population with chronic WAD. The study does not elucidate precise pain mechanisms but taken together with other studies exploring other aspects, it stresses the importance of individualizing the assessment and treatment of subjects with chronic WAD. A common clinical experience is that depression, anxiety and maladaptive coping strategies often are obstacles for successful medical treatment of chronic pain. The present study supports this experience and emphasizes the need for assessment of psychometric variables when planning the treatment of chronic WAD.

Risk factors for persistent problems following whiplash injury: results of a systematic review and meta-analysis

STUDY DESIGN

Systematic review and meta-analysis.

BACKGROUND

Whiplash-associated disorder (WAD) is the most common reported injury following motor vehicle accident. Evidence for prognosis and intervention are difficult to interpret due to differences in inception times, outcomes used, and sample heterogeneity.

METHODS

An extensive literature search was conducted to identify published studies of prognosis following whiplash. Rigorous inclusion criteria were applied to allow for meaningful results to be drawn. Data were extracted, transformed where necessary, and pooled to allow estimation of the odds ratio for any factor with at least 3 data points in the literature.

RESULTS

From 11 cohorts (n = 3193), 25 factors were identified with at least 3 data points in the existing literature. Of these, 9 were found to be significant predictors based on the odds ratio and confidence limits: no postsecondary education, female gender, history of previous neck pain,baseline neck pain intensity greater than 55/100, presence of neck pain at baseline, presence of headache at baseline, catastrophizing, WAD grade 2 or 3, and no seat belt in use at time of collision. Neck pain intensity, WAD grade, headache, and no postsecondary education were robust to publication bias.

CONCLUSIONS

Using a rigorous process for the identification and extraction of data from a homogenous subset of the prognostic WAD literature, we were able to identify several factors for which information is easy to collect clinically and could provide clinicians with a good sense of prognosis following whiplash injury.

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

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

Prognostic factors for chronic neck pain in persons with minor or moderate injuries in traffic accidents

Prognostic factors for chronic neck pain were identified in a prospective Norwegian insurance cohort comprising 636 persons with minor or moderate traffic injuries. One questionnaire was used at baseline and another at 3 years post-injury. Daily severe or very severe neck pain at three years follow up was defined as chronic neck pain. Eight significant independent prognostic factors for chronic neck pain were identified: (1) rear-end or frontal and rear-end collision, odds ratio (OR): 4.10 (95% confidence interval (CI): 1.72-10.82); (2) neck and/or shoulder pain before the accident, OR: 2.38 (95% CI: 1.07-5.37); (3) post-accident (a) memory and concentration problems, OR: 4.62 (95% CI: 1.99-11.20), (b) bodily tension, OR: 3.43 (95% CI: 1.49-8.42), (c) difficulties to climb stairs, OR: 5.03 (95% CI: 1.77-14.95), (d) difficulties to bend forward, OR: 4.85 (95% CI: 2.06-11.79), (e) difficulties to do heavy labour, OR: 3.70 (95% CI: 1.24-11.64); (4) beliefs in future work disability, OR: 2.64 (95% CI: 1.11-6.48). The results indicate that development of chronic neck pain is influenced by pre-accident neck and/or shoulder pain, the impact of the collision, as well as post-accident symptoms, perceived impaired function and pessimism for the future ability to work.

Classification of patients with whiplash associated disorders (WAD): reliable and valid subgroups based on the Multidimensional Pain Inventory (MPI-S)

BACKGROUND

Classification of patients with chronic whiplash associated disorders (WAD) into homogenous subgroups is an important objective in order to tailor interventions and to control for subgroup differences when evaluating treatment outcome.

AIMS

The aims of this study were to investigate if it was possible to replicate and describe the three cluster solution and profiles found in other pain groups and describe cluster profiles based on self-reported Multidimensional Pain Inventory-scores for patients with WAD three months after the injury, describe characteristics of the clusters in relation to disability, self-efficacy and coping at the same point in time and to validate the cluster solution by comparing clusters in disability, self-efficacy and coping over time.

METHODS

Ninety-one WAD-patients three months after the accident took part in the study. The measures used were the Multidimensional Pain Inventory-Swedish version (MPI-S), The Self-Efficacy Scale, The Coping Strategies Questionnaire and The Pain Disability Index. Cluster analysis was conducted for the total sample MPI-S subscale scores.

RESULTS

The adaptive copers cluster represented 42% of the sample, dysfunctional 34% of the sample, and interpersonally distressed 24% of the sample. The external validation of cluster solution showed that there were several significant differences between clusters in self-efficacy, disability and coping measures. There was also a significant interaction effect (clusterxtime) in disability (PDI). Patients in dysfunctional cluster reported a decreased disability over time.

CONCLUSIONS

These results support the presence of different subgroups among patients with whiplash associated disorders. This classification can be seen as a complement to a classification based on medical condition.

Whiplash Associated Disorders: Pathomechanics, Diagnosis, and Management

Whiplash has been defined as an injury mechanism, an injury, a medico-legal or social dilemma, and a complex chronic pain syndrome. Whiplash associated disorders are frequent in the cervical spine, especially as a result of a motor vehicle accident. The mechanisms responsible for whiplash-related tissue trauma are complex and a clinician's understanding of these complexities lends to a more complete appreciation for the anatomical structures and pathological processes that are involved, as well as a comprehensive diagnosis and appropriate management. While several classification scales have been developed for whiplash associated disorders, a thorough and tissue-specific examination is merited. Management should be directed toward pain reduction and normalization of mechanics. While conservative measures can address many of clinical sequelae of whiplash, both invasive pain management procedures and surgical interventions may be paramount to a patient's complete recovery.

Classification of neck movement patterns related to whiplash-associated disorders using neural networks

This paper presents a new method for classification of neck movement patterns related to Whiplash-associated disorders (WAD) using a resilient backpropagation neural network (BPNN). WAD are a common diagnosis after neck trauma, typically caused by rear-end car accidents. Since physical injuries seldom are found with present imaging techniques, the diagnosis can be difficult to make. The active range of the neck is often visually inspected in patients with neck pain, but this is a subjective measure, and a more objective decision support system, that gives a reliable and more detailed analysis of neck movement pattern, is needed. The objective of this study was to evaluate the predictive ability of a BPNN, using neck movement variables as input. Three-dimensional (3-D) neck movement data from 59 subjects with WAD and 56 control subjects were collected with a ProReflex system. Rotation angle and angle velocity were calculated using the instantaneous helical axis method and motion variables were extracted. A principal component analysis was performed in order to reduce data and improve the BPNN performance. BPNNs with six hidden nodes had a predictivity of 0.89, a sensitivity of 0.90 and a specificity of 0.88, which are very promising results. This shows that neck movement analysis combined with a neural network could build the basis of a decision support system for classifying suspected WAD, even though further evaluation of the method is needed.