***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 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: 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 prospect ively 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 Objective of the investigation : In a 6-month prospect i ve study of 141 consecutive acute whiplash-injured participants , and 40 acute , ankle-injured controls , pain and tenderness in the neck/head , and at a distant control site , were measured . Basic procedures : Muscle palpation and pressure algometry in five head/neck muscle-pairs were performed after 1 week and 1 , 3 and 6 months after injury . Algometry was performed at a distant control site . Main findings : Whiplash-injured patients had lowered pressure-pain-detection thresholds and higher palpation-score initially in the neck/head , but the groups were similar after 6 months , and the control site was not sensitized . Principal conclusion : Focal , but not generalized , sensitization to musculoskeletal structure is present until 3 months , but not 6 months , after whiplash injury , and probably does not play a major role in the development of late whiplash syndrome . Pressure algometry and palpation are useful clinical tools in the evaluation of neck and jaw pain in acute whiplash injury & 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 Objectives : To investigate sensory changes present in patients with chronic whiplash-associated disorders and chronic idiopathic neck pain using a variety of quantitative sensory tests to better underst and the pain processing mechanisms underlying persistent symptoms . Methods : A case control study was used with 29 subjects with chronic whiplash-associated disorders , 20 subjects with chronic idiopathic neck pain , and 20 pain-free volunteers .  Pressure pain thresholds  were measured over the articular pillars of C2-C3 , C5-C6 , the median , radial , and ulnar nerve trunks in the arm and over a remote site , the muscle belly of tibialis anterior . Heat pain thresholds , cold pain thresholds , and von Frey hair sensibility were measured over the cervical spine , tibialis anterior , and deltoid insertion . Anxiety was measured with the Short-Form of the Spielberger State Anxiety Inventory . Results : Pressure pain thresholds were decreased over cervical spine sites in both subject groups when compared with controls ( P < 0.05 ) . In the chronic whiplash-associated disorders group , pressure pain thresholds were also decreased over the tibialis anterior , median , and radial nerve trunks ( P < 0.001 ) . Heat pain thresholds were decreased and cold pain thresholds increased at all sites ( P < 0.03 ) . No differencesin heat pain thresholds or cold pain thresholds were evident in the idiopathic neck pain group at any site compared with the control group ( P > 0.27 ) . No abnormalities in von Frey hair sensibility were evident in either neck pain group ( P > 0.28 ) . Discussion : Both chronic whiplash-associated disorders and idiopathic neck pain groups were characterized by mechanical hyperalgesia over the cervical spine . Whiplash subjects showed additional widespread hypersensitivity to mechanical pressure and thermal stimuli , which was independent of state anxiety and may represent changes in central pain processing mechanisms . This may have implication s for future treatment approaches Abstract Patients with chronic whiplash associated disorders present with varied sensory , motor and psychological features . In this first instance it was question ed whether a multimodal program of physical therapies was an appropriate management to be broadly prescribed for these patients when it was known that some would have sensory features suggestive of a notable pain syndrome . A r and omised controlled trial was conducted with 71 participants with persistent neck pain following a motor vehicle crash to explore this question . Participants were r and omly allocated to receive either a multimodal physiotherapy program ( MPT ) or a self‐management program ( SMP ) ( advice and exercise ) . In the r and omisation process , participants were stratified according to the presence or not of widespread mechanical or cold hyperalgesia . The intervention period was 10 weeks and outcomes were assessed immediately following treatment . Even with the presence of sensory hypersensitivity in 72.5 % of subjects , both groups reported some relief of neck pain and disability ( Neck Disability Index ) and it was superior in the group receiving multimodal physiotherapy ( p = 0.04 ) . Post‐hoc observations however suggested that relief was marginal in the subgroup with both widespread mechanical and cold hyperalgesia . Further research is required to test the validity of this sub‐group observation and to test the effect of the intervention in the long term BACKGROUND The need exists for more definitive clinical signs indicative of abnormal central pain processing following a whiplash injury . Our observations have identified the presence of allodynia in the thoracic spine in patients with neck pain following whiplash injury . The evaluation of allodynia in the thoracic spine in a whiplash injured population may assist in the clinical diagnosis of patients believed to be suffering from central nervous system hypersensitivity . OBJECTIVE To evaluate for the presence of allodynia in a cohort of patients with whiplash injury . METHODS Thirty-one patients with whiplash injuries were evaluated in this prospect i ve study for the presence of allodynia in the thoracic spine . Thoracic vertebrae were marked by the initial evaluating clinician and a Wartenberg pinwheel was utilized to identify areas of hypersensitivity in the thoracic dermatomes . Patients were instructed to give no verbal clues , so only visual clues , as determined by the clinician , were assessed . A second clinician , blinded to the initial examination results , repeated the examination in the same fashion . RESULTS Thoracic allodynia was identified in 70.97 % of the observed population . There was a high level of agreement between observers ( Kappa coefficient of agreement , 0.8039 ; 95 % CI , 0.7465 , 0.8613 ; P < 0.05 ) . There was no predilection for a particular thoracic dermatome . CONCLUSION Thoracic allodynia was identified as a common , interrater-reliable , objective physical examination finding in this whiplash cohort Objectives ( 1 ) To investigate the development of hypoesthesia from soon after the whiplash injury to 6 months postinjury and ( 2 ) to determine differences in detection thresholds between those with initial features of poor recovery and those without these signs . Methods Fifty-two participants with acute whiplash-associated disorders ( WAD ) ( < 1 mo ) were classified as either “ high-risk ” ( n=17 ; Neck Disability Index > 30 ; sensory hypersensitivity ) or “ low risk ” ( n=35 ; without these signs ) .  Detection thresholds to electrical , thermal , and vibration stimuli and psychological distress were prospect ively measured within 1 month of injury and then 3 and 6 months postinjury . Detection thresholds were also measured in the 38 controls . Results Both WAD groups showed hypoesthesia ( vibration , electrical , and cold ) at 1 month postinjury . Vibration and electrocutaneous hypoesthesia persisted to 3 and 6 months only in the high-risk WAD group . Heat detection thresholds were not different between the groups at 1 month postinjury but were elevated in the high-risk group at 3 and 6 months . Both WAD groups were distressed at 1 month but this decreased by 3 months in the low-risk group . The differences in the Impact of Event Scale did not impact on any of the sensory measures . Discussion Sensory hypoesthesia is a feature of acute WAD but persists only in those at higher risk of poor recovery . These findings suggest the involvement of the central inhibitory mechanisms that may be sustained by ongoing nociception UNLABELLED 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 prospect i ve 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 h and into cold water for 2 min . The McGill Pain Question naire 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 : h and icap 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 OBJECTIVE To determine whether abnormalities of peripheral and central nociceptive sensory input processing exist outside areas of spontaneous pain in patients with fibromyalgia ( FM ) as compared with controls , by using quantitative sensory testing ( QST ) and a neurophysiologic paradigm independent from subjective reports . METHODS A total of 164 out patients with FM who were attending a self-management program were invited to participate in the study . Data for 85 patients were available and were compared with those for 40 non-FM controls matched for age and sex .  QST was performed using thermal , mechanical , and electrical stimuli at locations of nons 
    Output:
    
Findings suggest that although different central mechanisms seem to be involved in sustaining the pain complaints in whiplash patients , hypersensitivity of the central nervous system plays a significant role .
Persistent pain complaints , local and widespread hyperalgesia , referred pain and ( thoracic ) allodynia , decreased spinal reflex thresholds , inefficient diffuse noxious inhibitory controls activation and enhanced temporal summation of pain were established in chronic whiplash patients .