***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: We performed a prospect i ve study of patients with a whiplash trauma to the cervical spine to describe the incidence of these injuries and to evaluate prognostic factors for disability and recovery .  A total of 356 patients were enrolled in the study . All the patients received a comprehensive question naire after the injury , and 296 cases responded to the follow-up protocol more than 1 year after the accident . Disability related to the whiplash trauma was used as the outcome variable for the assessment of prognostic factors . The annual incidence of acute whiplash trauma in the catchment area was 4.2 per 1,000 inhabitants and 3.2 per 1,000 for whiplash-associated disorder grade s 1–3 . Thirty-two percent reported persisting disability at follow-up . The following factors were significantly associated with a poor prognosis : pretraumatic neck pain , low educational level , female gender , and whiplash-associated disorder grade s 2–3 & NA ; 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 aim ed to identify predictors of persistent spinal cord hyperexcitability . Pressure and cold pain thresholds , NFR responses ( threshold and pain VAS )  were prospect ively 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 Study Design . R and omized , parallel-group trial . Objective . To compare the effect of 3 early intervention strategies following whiplash injury . Summary of Background Data . Long-lasting pain and disability , known as chronic whiplash-associated disorder ( WAD ) , may develop after a forced flexion-extension trauma to the cervical spine . It is unclear whether this , in some cases disabling , condition can be prevented by early intervention . Active interventions have been recommended but have not been compared with information only . Methods . Participants were recruited from emergency units and general practitioners within 10 days after a whiplash injury and r and omized to : 1 ) immobilization of the cervical spine in a rigid collar followed by active mobilization , 2 ) advice to “ act-as-usual , ” or 3 ) an active mobilization program ( Mechanical Diagnosis and Therapy ) . Follow-up was carried out after 3 , 6 , and 12 months postinjury . Treatment effect was measured in terms of headache and neck pain intensity ( 0–10 ) , disability , and work capability . Results . A total of 458 participants were included . At the 1-year follow-up , 48 % of participants reported considerable neck pain , 53 % disability , and 14 % were still sick listed at 1 year follow-up . No significant differences were observed between the 3 interventions group . Conclusion . Immobilization , “ act-as-usual , ” and mobilization had similar effects regarding prevention of pain , disability , and work capability 1 year after a whiplash injury Background : Exposure to a whiplash injury implies a risk for development of chronic disability and h and icap , with reported frequencies ranging from 0 % to 50 % in follow-up studies . The exact risk for development of chronic whiplash syndrome is not known . Objective : To prospect ively determine the sensitivity and specificity of five possible predictors for h and icap following a whiplash injury . Methods : In a 1-year prospect i ve study of persons with acute whiplash injury ( n = 141 ) and control subjects who had acute ankle distortion ( n = 40 ) , pain intensity , number of nonpainful neurologic complaints , cervical mobility , workload during extension and flexion of the neck , and results of psychometric assessment were recorded . The consecutively sample d injured persons were assessed with structured and semistructured question naires , and underwent neurologic examination after 1 week and 1 , 3 , 6 , and 12 months . After 3 to 4 years , participants with whiplash injury were question ed about legal issues . Results : After 1 year , 11 ( 7.8 % ) persons with whiplash injury had not returned to usual level of activity or work . The best single estimator of h and icap was the cervical range-of-motion test , which had a sensitivity of 73 % and a specificity of 91 % ( p < 0.01 , Cox regression analysis ) . Accuracy and specificity increased to 94 % and 99 % when combined with pain intensity and other complaints . This increase was gained at the expense of a reduced sensitivity . Initiation of lawsuit within first month after injury did not influence recovery . Conclusion : The cervical range-of-motion test has a high sensitivity in prediction of h and icap after acute whiplash injury . The value of cervical range-of-motion test is further improved by additional recording of symptoms and pain intensity 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 prospect ively followed cohorts are needed to identify possible clinical ly 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 st and ard 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 Abstract Local sensitization to noxious stimuli has been previously described in acute whiplash injury and has been suggested to be a risk factor for chronic sequelae following acute whiplash injury . In this study , we prospect ively examined the development of tender points and mechano‐sensitivity in 157 acute whiplash injured patients , who fulfilled criteria for WAD grade 2 ( n = 153 ) or grade 3 ( n = 4 ) seen about 5 days after injury ( 4.8 ± 2.3 ) and who subsequently had or had not recovered 1 year after a cervical sprain .  Tender point scores and stimulus – response function for mechanical pressure were determined in injured and non‐injured body regions at specific time‐points after injury . Thirty‐six of 157 WAD grade 2 patients ( 22.9 % ) had not recovered , defined as reduced work capacity after 1 year . Non‐recovered patients had higher total tender point scores after 12 ( p < 0.05 ) , 107 ( p < 0.05 ) and 384 days ( p < 0.05 ) relative to those who recovered . Tenderness was found in the neck region and in remote areas in non‐recovered patients . The stimulus – response curves for recovered and non‐recovered patients were similar after 12 days and 107 days after the injury , but non‐recovered patients had steeper stimulus – response curves for the masseter ( p < 0.02 ) and trapezius muscles ( p < 0.04 ) after 384 days . This study shows early mechano‐sensitization after an acute whiplash injury and the development of further sensitization in patients with long‐term disability A classification of injury and a follow-up schedule were proposed by the Quebec Task Force ( QTF ) in 1995 . No general agreement about the clinical usefulness of the WAD-classification or of the suggested follow-up regimen exists . A series of 186 consecutive cases seen in the emergency room during the acute phase after a whiplash injury was prospect ively studied for 1 year . All findings including history and physical findings were recorded using st and ardized QTF protocol s. In one group follow-up visits were done according to the QTF regimen : at 1 , 3 , 6 , 12 weeks and 1 year after the accident ; in a control group no visit was scheduled . The outcome variable was neck pain at 1 year after the accident . After 1 year , 18 % of the total number of patients had significant neck pain . Risk factors for chronic neck pain at 1 year after whiplash injury were : neck pain before the accident and a high degree of emotional distress at the time of the accident ; both factors independently associated with a tenfold increased risk of developing chronic neck pain . Neither the WAD classification nor the QTF follow-up regimen could be linked to a better outcome . In this study the outcome was associated with patient-specific characteristics and not with physical signs of injury , the depth of the initial evaluation or the follow-up regimen This is a 1-year prospect i ve study to investigate the prognostic value of coping strategies such as catastrophising for persistent pain after a whiplash injury . A consecutive series of 96 patients who were seen in the emergency room in the acute phase after the injury were followed prospect ively for 1 year . Age , gender and whether or not pain in the neck preceded the accident was recorded . Cases involving fractures or dislocations of the cervical spine , head trauma or pre-existing neurological disorders were not included . The mean interval between the accident and the initial examination was 3+/-2(S.D. ) days . Coping was measured using the  Coping Strategies Question naire ( CSQ ) . The outcome parameter was self-reported neck pain at 1 year after the motor vehicle accident . At 1 year , 34 % of the patients had neck pain . Women developed chronic neck pain more often than men ( 71 % versus 29 % ) ; they also had significantly higher coping activity , such as diverting attention , praying or hoping ( p<0.05 ) ,  catastrophising and increasing behavioural activities ( p<0.0001 ) . Women reported pain in the neck or shoulder more often before the accident and this was the only statistically significant predictor of chronic symptoms when analysed by logistic regression ( odds ratio 4.5 ) . To conclude , we found no evidence that the different coping patterns during the early phase after a whiplash injury influenced the prognosis Objective : To establish the aetiological influences of  persistent neck pain following a motor vehicle collision and to construct a model for use in the emergency department for identifying patients at high risk of persistent symptoms . Design : Prospect i ve cohort study . Patients recruited from hospital emergency departments were sent a question naire to gather information on various exposures . They were followed up at 1 , 3 , and 12 months to identify those with persistent symptoms . Main outcome measure : Persistent neck pain ( pain at 1 , 3 , and 12 months after collision ) . Results : The baseline survey included 765 patients . Subsequently , 480 completed a question naire at each follow up time point , of whom 128 ( 27 % ) reported neck pain on each occasion . Few collision specific factors predicted persistent neck pain . In contrast , a high level of general psychological distress , pre-collision history of widespread body pain , type of vehicle , whiplash associated symptoms , and initial neck disability best predicted the persistence of symptoms . Furthermore , these factors , in combination , accounted for more than a fivefold increase in the risk of persistent neck pain . Conclusion : The greatest predictors of persistent neck pain following a motor vehicle collision relate to psychological distress and aspects of pre-collision health rather than to various attributes of the collision itself . With these factors , and those relating to initial injury severity , it is possible to identify a subgroup of patients presenting with neck pain with the highest risk of persistent symptoms . Thus , it is possible to identify whiplash patients with a poor prognosis and to provide closer follow up and specific attention to management in these individuals A prospect i ve study was used to : ( 1 ) quantify potential risk factors for whiplash associated disorder following a rear- 
    Output:
    
These factors can be easily identified in a clinical setting to provide estimates of prognosis following whiplash