Prognosis following a second whiplash injury

Delayed recovery in patients with whiplash-associated disorders

BACKGROUND

Prognosis of whiplash injury has been found to be related to a number of sociodemographic, treatment and clinical factors. In the current study, we attempt to identify several novel prognostic factors for delayed recovery in whiplash-associated disorders (WADs), using a validated and reliable measure of recovery.

PATIENTS AND METHODS

Retrospective review of a large database of a national network of physiotherapy and rehabilitation service providers in Canada yielded 5581 individuals injured in motor vehicle collisions. Cases were grouped into 3 cohorts based on time lapsed between injury date and initial presentation. Acute (n=3075), early chronic (n=958) and chronic (n=1548) patient cohorts were compared regarding treatment outcome and relative distribution of 29 prognostic factors. Outcome was defined by a minimally important clinical change (10%) on a previously validated disability questionnaire between initial and discharge rehabilitation visits.

RESULTS

Analysis demonstrated positive outcomes to be proportionally fewer in the chronic cohort (52.1%) relative to the early chronic (61.4%), which was in turn lower than the acute cohort (72.3%). Furthermore, individuals presenting with chronic pain were more likely to: (1) be female; (2) present with lower limb pain or nonorganic signs; (3) have returned to work; (4) have retained a lawyer; or (5) have undergone previous spinal surgery, and were less likely to: (1) present with neck or midback pain; (2) live in Ontario or Nova Scotia; or (3) have modified duties upon return to work. Acute, early chronic and chronic cohorts were also found to differ in the distribution of several other prognostic factors at initial clinical visit.

CONCLUSIONS

Recovery in whiplash-associated disorder appears to be multifactorial with both medical and non-injury related factors influencing outcome. Further characterisation of these factors may prove invaluable in guiding future clinical treatment and referral practices.

Human subject rear passenger symptom response to frontal car-to-car low-speed crash tests

OBJECTIVE

The purpose of this study was to determine whether healthy adult volunteers report symptoms following exposure to low-speed frontal crashes at low velocities.

METHODS

Nineteen medically screened, healthy, informed, and willing volunteers (17 men, 2 women; mean age, 37 years) were exposed to low-speed frontal crashes. All volunteers were seated in the rear seat position of the bullet vehicle. Closing velocities ranged from 4.1 to 8.3 mph (mean, 6.7 mph). For the bullet vehicle, the delta V ranged from 1.4 to 3.9 mph with a mean of 2.8 mph.

RESULTS

Eighty-eight percent of volunteers attributed symptoms of discomfort to their crash exposure. All reported symptoms were transient, and none required medical treatment. The mean duration was 1 day.

CONCLUSIONS

Even at relatively low speeds, there is no lower threshold below which it can be reasonably assumed that healthy and prepared volunteer rear seat passengers will not sustain some level of minor injury in a frontal collision. Although the reported mean delta V for injured persons in real-world frontal crashes has been reported to be as high as 8.1 mph, this does not offer any insight into the minimum threshold for such injuries among all at-risk vehicle occupants.

[Anatomy of the cervical spine]

BACKGROUND

Knowledge of biomechanics and the cervical spine's anatomy has become more topical as the incidence of whiplash neck disorders has increased. Unfortunately, injuries after traffic accidents are often brought to court, where the medical expert's knowledge is of utmost importance to ensure a correct medical evaluation.

MATERIAL AND METHODS

The article is based on information identified through non-systematic searches of PubMed and on the author's experience as a professor of anatomy.

RESULTS

The cervical spine is particularly vulnerable to forces perpendicular to the length axis. Stability depends largely on the soft tissue. Injuries of soft tissue (especially in ligaments and intervertebral discs) may lead to instability and periosteal reaction with subsequent new formation of bone.

INTERPRETATION

The cervical spine is a relatively weak and vulnerable part of the body. One should consider locally restricted new formations of tissue with corresponding height reduction of the intervertebral disc as a sign of genuine injury.

Whiplash injury

This review discusses the causes, outcome and prevention of whiplash injury, which costs the economy of the United Kingdom approximately £3.64 billion per annum. Most cases occur as the result of rear-end vehicle collisions at speeds of less than 14 mph. Patients present with neck pain and stiffness, occipital headache, thoracolumbar back pain and upper-limb pain and paraesthesia. Over 66% make a full recovery and 2% are permanently disabled. The outcome can be predicted in 70% after three months.

Influence of a previous neck sprain on recovery after whiplash injury

The impact of a previous neck sprain on recovery from whiplash injury is unknown as published studies have produced conflicting results. This article reviews the literature on the prognosis of a second whiplash injury, distinguishing between previous injuries with and without complete recovery. The best available evidence suggests that a previous injury with incomplete recovery represents an adverse prognostic indicator. However, where there has been complete recovery, the prior injury does not influence the prognosis.

Underestimation of severity of previous whiplash injuries

INTRODUCTION

We noted a report that more significant symptoms may be expressed after second whiplash injuries by a suggested cumulative effect, including degeneration. We wondered if patients were underestimating the severity of their earlier injury.

PATIENTS AND METHODS

We studied recent medicolegal reports, to assess subjects with a second whiplash injury. They had been asked whether their earlier injury was worse, the same or lesser in severity.

RESULTS

From the study cohort, 101 patients (87%) felt that they had fully recovered from their first injury and 15 (13%) had not. Seventy-six subjects considered their first injury of lesser severity, 24 worse and 16 the same. Of the 24 that felt the violence of their first accident was worse, only 8 had worse symptoms, and 16 felt their symptoms were mainly the same or less than their symptoms from their second injury. Statistical analysis of the data revealed that the proportion of those claiming a difference who said the previous injury was lesser was 76% (95% CI 66-84%). The observed proportion with a lesser injury was considerably higher than the 50% anticipated.

CONCLUSIONS

We feel that subjects may underestimate the severity of an earlier injury and associated symptoms. Reasons for this may include secondary gain rather than any proposed cumulative effect.

Factors affecting the timing of recovery from whiplash neck injuries: study of a cohort of 134 patients pursuing litigation

INTRODUCTION

A cohort of 134 patients presenting in medico-legal practice with whiplash neck injury following a motor vehicle accident was studied prospectively by personal interviewing.

MATERIALS AND METHODS

Injury- and patient-related factors with possible influence to the timing of recovery were analysed with univariate and multivariate statistical methods.

RESULTS

Logistic regression showed significant association between high physical demand patient occupation and recovery within 6 months from injury (P = 0.036, coefficient 1.5, odds ratio 4.47) while initiation of physiotherapy treatment was associated with prolongation of symptoms for more than 6 months following injury (P < 0.001, coefficient -2.6, odds ratio 0.08). An association between development of arm pain (P = 0.01), upper limb numbness or paraesthesia (P = 0.03) and bilateral trapezius pain (P = 0.04) and persistence of whiplash-related symptoms was also observed. These findings must be taken into account in evaluation and treatment of patients with acute whiplash injuries pursuing litigation.

Factors predicting outcome after whiplash injury in subjects pursuing litigation

Records of 277 patients presenting for medicolegal reporting following isolated whiplash injury were studied retrospectively. A range of pre-accident, accident and response variables were recorded. Multivariate analysis was used to determine the main factors that predict physical and psychological outcome after whiplash injury. The factors that showed significant association with poor outcome on both physical and psychological outcome scales were pre-injury back pain, high frequency of General Practitioner attendance, evidence of pre-injury depression or anxiety symptoms, front position in the vehicle and pain radiating away from the neck after injury. The strongest associations were with factors that are present before impact. In this selected cohort of patients, there is a physical and a psychological vulnerability that may explain the widely varied response to low violence indirect neck injury.

Fibromyalgia after motor vehicle collision: evidence and implications

OBJECTIVE

Assess currently available evidence regarding the ability of a motor vehicle collision (MVC) to trigger the development of fibromyalgia (FM).

METHODS

Consensus standards developed by the American College of Rheumatology Environmental Disease Study Group were used to assess the ability of an MVC to trigger FM.

RESULTS

Increasing evidence suggests that FM and related disorders are characterized by abnormalities in central nervous system function related to sensory processing, autonomic regulation, and neuroendocrine function. MVC trauma appears capable of triggering FM, but generally not through direct biomechanical injury. Instead, the evidence suggests that MVC trauma can act as a "stressor," which in concert with other factors, such as an individual's biologic vulnerability, psychosocial factors, cultural factors, and so on, may result in the development of chronic widespread pain and other somatic symptoms. MVC trauma is only one of many stressors which can trigger such disorders, and the environment within which the stressor is experienced (biological and psychosocial) may largely determine whether there is an adverse physiologic result or not.

CONCLUSIONS

The evidence that MVC trauma may trigger FM meets established criteria for determining causality, and has a number of important implications, both for patient care, and for research into the pathophysiology and treatment of these disorders.

Whiplash associated disorders: a review of the literature to guide patient information and advice

OBJECTIVES

To review the literature and provide an evidence based framework for patient centred information and advice on whiplash associated disorders.

METHODS

A systematic literature search was conducted, which included both clinical and non-clinical articles to encompass the wide range of patients' informational needs. From the studies and previous reviews retrieved, 163 were selected for detailed review. The review process considered the quantity, consistency, and relevance of all selected articles. These were categorised under a grading system to reflect the quality of the evidence, and then linked to derived evidence statements.

RESULTS

The main messages that emerged were: physical serious injury is rare; reassurance about good prognosis is important; over-medicalisation is detrimental; recovery is improved by early return to normal pre-accident activities, self exercise, and manual therapy; positive attitudes and beliefs are helpful in regaining activity levels; collars, rest, and negative attitudes and beliefs delay recovery and contribute to chronicity. These findings were synthesised into patient centred messages with the potential to reduce the risk of chronicity.

CONCLUSIONS

The scientific evidence on whiplash associated disorders is of variable quality, but sufficiently robust and consistent for the purpose of guiding patient information and advice. While the delivery of appropriate messages can be both oral and written, consistency is imperative, so an innovative patient educational booklet, The Whiplash Book, has been developed and published.