***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: The aim of this case series was to investigate changes in pain and pressure pain sensitivity after manual treatment of active trigger points ( TrPs ) in the shoulder muscles in individuals with unilateral shoulder impingement . Twelve patients ( 7 men , 5 women , age : 25 ± 9 years ) diagnosed with unilateral shoulder impingement attended 4 sessions for 2 weeks ( 2 sessions/week ) . They received TrP pressure release and neuromuscular interventions over each active TrP that was found . The outcome measures were pain during arm elevation ( visual analogue scale , VAS ) and pressure pain thresholds ( PPT ) over levator scapulae , supraspinatus infraspinatus , pectoralis major , and tibialis anterior muscles . Pain was captured pre-intervention and at a 1-month follow-up , whereas PPT were assessed pre- and post-treatment , and at a 1-month follow-up . Patients experienced a significant ( P < 0.001 ) reduction in pain after treatment ( mean ± SD : 1.3 ± 0.5 ) with a large effect size ( d > 1 ) . In addition , patients also experienced a significant increase in PPT immediate after the treatment ( P < 0.05 ) and one month after discharge ( P < 0.01 ) , with effect sizes ranging from moderate ( d = 0.4 ) to large ( d > 1).A significant negative association ( r(s ) = -0.525 ; P = 0.049 ) between the increase in PPT over the supraspinatus muscle and the decrease in pain was found : the greater the decrease in pain , the greater the increase in PPT . This case series has shown that manual treatment of active muscle TrPs can help to reduce shoulder pain and pressure sensitivity in shoulder impingement . Current findings suggest that active TrPs in the shoulder musculature may contribute directly to shoulder complaint and sensitization in patients with shoulder impingement syndrome , although future r and omized controlled trials are required Background Lack of habituation during repetitive stimulation is the most consistent interictal abnormality of cortical information processing observed in migraine . Preventive migraine treatments might act by stabilizing cortical excitability level and thus the habituation to external stimuli . Methods We examined the effects of preventive treatment with topiramate on migraineur ’s habituation to nociceptive stimulation . Scalp potentials were evoked by Nd-YAP Laser stimulation of the h and dorsum and supraorbital region in 13 patients with migraine without aura ( MO ) and 15 healthy volunteers ( HV ) . The exam was repeated in MO before and after treatment . Results We observed a lack of habituation and lower initial amplitudes in MO compared to HV . These abnormalities reached statistical significance for N1 LEPs component , generated in the secondary somatosensory cortex ( SII ) , but not for N2/P2 complex , generated in the insula and anterior cingulated cortex ( ACC ) . Topiramate normalized the N1 habituation pattern in MO , with a significant correlation between clinical effects and normalization of neurophysiological responses . Conclusions Our results indicate a modulating action of topiramate on cortical processing of sensorial stimuli , mainly regarding the sensory-discriminative component of pain , elaborated by SII , without a significant effect on the affective dimension of pain , in which the ACC has an important role Visually induced analgesia has been correlated with the affective content of pleasant , neutral or unpleasant pictures . The aim of the present study was to assess the effect of affective images vision on laser evoked potentials and pain perception , in a cohort of healthy subjects and migraine patients . Twenty-two healthy subjects and 24 migraine without aura patients ( recorded during the inter-critical phase ) participated in the study . Eighty-four colour slides , arranged in two blocks , each consisting of 14 pleasant , 14 unpleasant and 14 neutral images , in r and om presentation , were chosen from the International Affective Picture System . The CO(2 ) laser stimuli were delivered on the dorsum of the right h and and supra-orbital zone at 7.5-watt intensity and 25-ms duration , in basal condition and during the viewing of affective pictures . Migraine patients expressed higher scores of valence and arousal for pleasant and unpleasant pictures , compared to controls . In both groups , a late positive potential in the 400 - 700 ms time range was clear for pleasant and unpleasant pictures , but its amplitude was significantly reduced in migraine patients . The pain rating and the N2 component were reduced in both groups during the visual task compared to basal condition . In migraineurs and controls the P2 wave was reduced during the vision of pleasant pictures , compared to basal condition . This indicates that stimulation by images with different affective content reduces subjective pain for a cognitive mechanism of attentive engagement , while a special inhibition of later LEPs is produced by a positive emotional impact . In migraine , affective images are able to modulate pain perception and LEPs , differently from other modalities of distraction , suggesting a possible emotive elaboration of painful stimuli Thirty-three migraineurs and 23 healthy controls were su bmi tted to pressure algometry before and after light-induced discomfort was elicited by progressive light stimulation in a monoblind fashion . Pressure algometries were performed on the emergence of the supraorbital , infraorbital , mental and greater occipital nerves , and over the temporal muscles , always throughout the same sequence and from right to left . Measurements were carried out before and immediately after light stimulation and after 10 min of the second algometry . The final result for each site measured at each time-point was the mean of the three measurements . Light stimulation was carried out progressively until light-induced discomfort was reported , to a maximum of 20 000 lux . A heat-blocking glass protected patients ' eyes . Migraineurs presented significant and persistent drops in pain perception thresholds after light stimulation , at all sites tested ( P = 0.002 to < 0.0001 ) . These drops were not seen in controls , in whom , conversely , a less significant increase was seen on right infraorbital and left temporal muscle sites . Our results indicate that in migraineurs , light may have a relevant role in trigeminal and cervical pain perception thresholds STUDY DESIGN R and omized clinical trial . OBJECTIVES To determine the effects of trigger point dry needling ( TrPDN ) on neck pain , widespread pressure pain sensitivity , and cervical range of motion in patients with acute mechanical neck pain and active trigger points in the upper trapezius muscle . BACKGROUND TrPDN seems to be effective for decreasing pain in individuals with upper-quadrant pain syndromes . Potential effects of TrPDN for decreasing pain and sensitization in individuals with acute mechanical neck pain are needed . Methods Seventeen patients ( 53 % female ) were r and omly assigned to 1 of 2 groups : a single session of TrPDN or no intervention ( waiting list ) . Pressure pain thresholds over the C5 - 6 zygapophyseal joint , second metacarpal , and tibialis anterior muscle ; neck pain intensity ; and cervical spine range-of-motion data were collected at baseline ( pretreatment ) and 10 minutes and 1 week after the intervention by an assessor blinded to the treatment allocation of the patient . Mixed-model analyses of variance were used to examine the effects of treatment on each outcome variable . RESULTS Patients treated with 1 session of TrPDN experienced greater decreases in neck pain , greater increases in pressure pain threshold , and higher increases in cervical range of motion than those who did not receive an intervention at both 10 minutes and 1 week after the intervention ( P<.01 for all comparisons ) . Between-group effect sizes were medium to large immediately after the TrPDN session ( st and ardized mean score differences greater than 0.56 ) and large at the 1-week follow-up ( st and ardized mean score differences greater than 1.34 ) . CONCLUSION The results of the current r and omized clinical trial suggest that a single session of TrPDN may decrease neck pain intensity and widespread pressure pain sensitivity , and also increase active cervical range of motion , in patients with acute mechanical neck pain . Changes in pain , pressure pain threshold , and cervical range of motion surpassed their respective minimal detectable change values , supporting clinical ly relevant treatment effects . Level of Evidence Therapy , level 1b- The aim of this study was to evaluate the function of pain modulating systems subserving diffuse noxious inhibitory controls ( DNICs ) in primary headaches . DNICs were examined in 24 migraineurs , 17 patients with chronic tension-type headache ( CTTH ) and 20 healthy subjects by means of nociceptive flexion RIII reflex and the cold pressor test ( CPT ) as heterotopic noxious conditioning stimulation ( HNCS ) . The subjective pain thresholds ( Tp ) and the RIII reflex threshold ( Tr ) were significantly lower in CTTH vs. controls . In controls a significant inhibition of the RIII reflex was observed during the CPT ( -30± , P < 0.05 ) . Conversely , migraine and CTTH patients  showed facilitation ( + 31± , P < 0.05 and + 40± , P < 0.01 , respectively ) of the RIII reflex during the HNCS . This study demonstrates a dysfunction in systems subserving DNICs in both migraine and CTTH . Impairment of endogenous supraspinal pain modulation systems may contribute to the development and /or maintenance of central sensitization in primary headaches Pain perception studies in migraine patients have shown trigeminal and peripheral pain facilitation during the migraine attack . We were interested in differences of trigeminal and peripheral pain perception between migraine patients during the migraine interval and healthy subjects . Perception of electrical pain stimulation was measured in 20 migraine subjects outside a migraine attack ( 10 migraine with aura and 10 migraine without aura ) and in 20 healthy subjects . We recorded sensory and pain thresholds , pain ratings  after suprathreshold stimulation  , and pain rating  after two trains of repetitive stimulation ( i.e. , pain facilitation ) . Migraine subjects showed a significantly higher pain rating after suprathreshold stimulation in the trigeminal region as compared to healthy subjects ( 4.8 ± 1.6 versus 3.8 ± 2.2 , p < 0.04 after Bonferroni correction ) but not in the peripheral region . Furthermore , migraine subjects showed a pain facilitation after repetitive trigeminal stimulation whereas healthy subjects showed a pain habituation . We observed no significant differences between migraine subjects and healthy subjects for all parameters in the peripheral stimulation . Migraine patients with and without aura did not differ in any parameter . All subjects showed decreased sensory and pain thresholds after trigeminal as compared to peripheral stimulation . Migraine subjects show an increased pain perception after trigeminal but not after peripheral pain stimulation as compared to healthy subjects . This phenomenon is probably due to the observed pain facilitation after painful trigeminal stimulation Background The mechanisms associating sleep and migraine are unknown . No previous polysomnographic ( PSG ) or pain-threshold ( PT ) study has compared patients with sleep-related migraine attacks ( SM ) , non-sleep related migraine attacks ( NSM ) and healthy controls . Methods We have performed a blinded , prospect i ve exploratory study with case – control design . Thirty-four healthy controls , 15 patients with SM and 18 patients with NSM had interictal PSG heat-  , cold- and pressure PT ( HPT , CPT , PPT )  recordings  and completed diary- and question naire on sleep and headache related aspects . Results NSM patients had more slow-wave sleep ( SWS ) and more K-bursts than SM patients ( K-bursts : p = 0.023 and SWS : p = 0.030 ) and controls ( K-bursts : p = 0.009 and SWS : 0.041 ) . NSM patients also had lower HPT and CPT than controls ( p = 0.026 and p = 0.021 ) . In addition , SM patients had more awakenings and less D-bursts than controls ( p = 0.025 and p = 0.041 ) . ConclusionS M- and NSM patients differed in objective - , but not subjective sleep quality . NSM patients had PSG findings indicating foregoing sleep deprivation . As foregoing sleep times were normal , a relative sleep deficit might explain reduced PT among NSM patients . The SM patients had signs of slightly disturbed sleep UNLABELLED This study evaluated the contribution of myofascial trigger points ( TrPs ) to  migraine pain . Seventy-eight migraine patients with cervical active TrPs whose referred areas ( RAs ) coincided with migraine sites ( frontal/temporal ) underwent electrical pain threshold measurement in skin , subcutis , and muscle in TrPs and RAs at baseline and after 3 , 10 , 30 , and 60 days ; migraine pain assessment ( number and intensity of attacks ) for 60 days before and 60 days after study start . Fifty-four patients ( group 1 ) underwent TrP anesthetic infiltration on the 3rd , 10th , 30th , and 60th day ( after threshold measurement ) ; 24 ( group 2 ) received no treatment .  Twenty normal subjects underwent threshold measurements in the same sites and time points as patients . At baseline , all patients showed lower than normal thresholds in TrPs and RAs in all tissues ( P < .001 ) . During treatment in group 1 , all thresholds increased progressively in TrPs and RAs ( P < .0001 ) , with sensory normalization of skin/subcutis in RAs at the end of treatment ; migraine pain decreased ( P < .001 ) . Threshold increase in RAs and migraine reduction correlated linearly ( .0001 < P < .006 ) . In group 2 and normal subjects , no changes occurred . Cervical TrPs with referred areas in migraine sites thus contribute substantially to migraine symptoms , the peripher 
    Output:
    
Importantly , lower pressure pain threshold in patients with migraine was found in local areas but not in nonlocal areas .
This meta- analysis indicates that the alterations in nociceptive processing of patients with migraine may be modality , measure , and location specific .