***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: UNLABELLED This study compared the effect of 2 specific cervical flexor muscle exercise protocol s on immediate pain relief in the cervical spine of people with chronic neck pain . In addition , the study evaluated whether these exercise protocol s elicited any systemic effects by study ing sympathetic nervous system ( SNS ) function and pain at a location distant from the cervical spine . Participants were r and omly allocated into either a cranio-cervical flexion ( CCF ) coordination exercise group ( n = 24 ) or a cervical flexion ( CF ) endurance exercise group ( n = 24 ) . Measures of pain and SNS function were recorded immediately before and after a single session of the exercise interventions .  Pain measures included visual analogue scale ( VAS ) ratings of neck pain at rest and during active cervical motion and pressure pain threshold ( PPT ) and thermal pain threshold ( TPT ) recordings over the cervical spine and at a remote site on the leg . Measures of SNS function consisted of blood flow , skin conductance , skin temperature , heart rate , and blood pressure . Immediately after 1 session of exercise , there was a reasonably sized increase of 21 % ( P < .001 , d = 0.88 ) and 7.3 % ( P = .03 , d = 0.47 ) in PPT locally at the neck for the CCF exercise and the CF exercise , respectively . There were no changes in local neck TPT with either exercise . Pressure pain threshold and TPT at the leg and SNS did not change after exercise . Only the CCF exercise demonstrated a small improvement in VAS ratings during active movement ( change on 10-cm VAS : CCF , 0.42 cm ( P = .04 ) . This study shows that specific CCF therapeutic exercise is likely to provide immediate change in mechanical hyperalgesia local to the neck with translation into perceived pain relief on movement in patients with chronic neck pain . PERSPECTIVE This study showed an immediate local mechanical hypoalgesic response to specific exercise of the cervical spine . Underst and ing the pain-relieving effects of exercise will assist the clinician in prescribing the most appropriate exercise protocol s for patients with chronic neck pain Introduction . Cupping has been used since antiquity in the treatment of pain conditions . In this pilot study , we investigated the effect of traditional cupping therapy on chronic nonspecific neck pain ( CNP ) and mechanical sensory thresholds . Methods . Fifty CNP patients were r and omly assigned to treatment ( TG , n = 25 ) or waiting list control group ( WL , n = 25 ) . TG received a single cupping treatment .  Pain at rest ( PR ) , pain related to movement ( PM ) , quality of life ( SF-36 ) , Neck Disability Index ( NDI ) , mechanical detection ( MDT ) , vibration detection ( MDT ) , and pressure pain thresholds ( PPT ) were measured before and three days after a single cupping treatment . Patients also kept a  pain  and medication diary ( PaDi , MeDi ) during the study . Results . Baseline characteristics were similar in the two groups . After cupping TG reported significantly less pain ( PR : −17.9 mm VAS , 95%CI −29.2 to −6.6 ; PM : −19.7 , 95%CI −32.2 to −7.2 ; PaDi : −1.5 points on NRS , 95%CI −2.5 to −0.4 ; all P < 0.05 ) and higher quality of life than WL ( SF-36 , Physical Functioning : 7.5 , 95%CI 1.4 to 13.5 ; Bodily Pain : 14.9 , 95%CI 4.4 to 25.4 ; Physical Component Score : 5.0 , 95%CI 1.4 to 8.5 ; all P < 0.05 ) . No significant effect was found for NDI , MDT , or VDT , but TG showed significantly higher PPT at pain- areas than WL ( in lg(kPa ) ; pain-maximum : 0.088 , 95%CI 0.029 to 0.148 , pain-adjacent : 0.118 , 95%CI 0.038 to 0.199 ; both P < 0.01 ) . Conclusion . A single application of traditional cupping might be an effective treatment for improving pain , quality of life , and hyperalgesia in CNP 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 Background Current evidence suggests that spinal manipulative therapy ( SMT ) is effective in the treatment of people with low back pain ( LBP ) ; however , the corresponding mechanisms are unknown . Hypoalgesia is associated with SMT and is suggestive of specific mechanisms . Objective The primary purpose of this study was to assess the immediate effects of SMT on thermal pain perception in people with LBP . A secondary purpose was to determine whether the result ing hypoalgesia was a local effect and whether psychological influences were associated with changes in pain perception . Design This study was a r and omized controlled trial . Setting A sample of convenience was recruited from community and outpatient clinics . Participants Thirty-six people ( 10 men , 26 women ) currently experiencing LBP participated in the study . The average age of the participants was 32.39 ( SD=12.63 ) years , and the average duration of LBP was 221.79 ( SD=365.37 ) weeks . Intervention and Measurements Baseline demographic and psychological measurements were obtained , followed by quantitative sensory testing to assess temporal summation and Aδ fiber – mediated pain perception . Next , participants were r and omly assigned to ride a stationary bicycle , perform low back extension exercises , or receive SMT . Finally , the same quantitative sensory testing protocol was reassessed to determine the immediate effects of each intervention on thermal pain sensitivity . Results Hypoalgesia to Aδ fiber – mediated pain perception was not observed . Group-dependent hypoalgesia of temporal summation specific to the lumbar innervated region was observed . Pair-wise comparisons indicated significant hypoalgesia in participants who received SMT , but not in those who rode a stationary bicycle or performed low back extension exercises . Psychological factors did not significantly correlate with changes in temporal summation in participants who received SMT . Limitations Only immediate effects of SMT were measured , so the authors are unable to comment on whether the inhibition of temporal summation is a lasting effect . Furthermore , the authors are unable to comment on the relationship between their findings and changes in clinical pain . Conclusions Inhibition of Aδ fiber – mediated pain perception was similar for all groups . However , inhibition of temporal summation was observed only in participants receiving SMT , suggesting a modulation of dorsal horn excitability that was observed primarily in the lumbar innervated area OBJECTIVE Several studies have shown that exposure to opioids for short or long periods alters pain sensitivity . Little is known about changes in pain sensitivity during and after tapering of long-term prescribed opioid treatment in chronic low-back pain ( cLBP ) patients . DESIGN The goal of this prospect i ve longitudinal study was to investigate pain sensitivity in a homogeneous patient population ( cLBP patients only ) after tapering of long-term ( 17 months )  opioid use and to monitor the changes in pain sensitivity for 6 months . METHODS Pain sensitivity ( thermal sensation and thermal pain thresholds in low back and nondominant h and ) was measured by quantitative sensory testing ( QST ) at 1 day before ( T1 ) , 3 weeks after ( T2 ) , and 6 months after the start of opioid tapering ( T3 ) in 35 patients with both cLBP and opioid medication ( OP ) , 35 opioid-naïve cLBP patients ( ON ) , and 28 individuals with neither pain nor opioid intake ( HC ) . RESULTS Significant differences in heat pain thresholds were found among the three groups at all three time points ( T1 : P=0.001 , T2 : P=0.015 , T3 : P=0.008 ) , but not between the two patient groups . OP patients showed lower cold pain thresholds at T2 than ON patients and HC . At T3 , the heat pain thresholds of OP patients still remained lower than HC ( P=0.017 ) , while those of ON patients were normalized . CONCLUSIONS Our findings suggest that long-term use of opioids does not reduce pain sensitivity in cLBP patients ; opioid tapering may induce brief hyperalgesia that can be normalized over a longer period Chronic pain is often associated with hyperalgesia in cross-sectional studies . In the present study , a r and om cohort of 40-year-old individuals ( n = 264 ) from the general population was assessed for low back pain ( LBP ) status and pressure pain threshold ( PPT )  , with follow-up assessment 4 and 8 years later . Low PPT at baseline as a potential risk factor for the development of LBP was investigated longitudinally and the association between LBP and hyperalgesia was studied cross-sectionally at baseline and 8-year follow-up . Generalized ( p < 0.03 ) and localized pressure hyperalgesia ( p < 0.02 ) was found in participants with long-lasting LBP , but not with recent LBP ( p > 0.08 ) . Of the participants without recent or long-lasting LBP , those with a low PPT at baseline ( lower 10 % percentile ) had no increased risk of developing LBP ( p > 0.05 ) . The findings indicate that PPT decreases as a consequence of long-lasting pain , whereas a low PPT seems not to constitute a separate risk factor for the development of LBP Thirty patients with whiplash injuries were examined 1 to 55 months after the accidents .  Pain had appeared on the day of the accident in 24 ( 80 % ) of the patients and with different delays in the remainder . The mean pain intensity was 43 mm ( SD 26 ) on a visual analogue scale ( VAS ) . All patients had pain in the neck , 17 - 33 % had headache  and 6 - 17 % had pain in various regions of the arms . Thirteen patients ( 43 % ) suffered from constant pain , while 17 ( 57 % ) had pain-free periods . Muscle tenderness was higher at all tested sites compared with controls . The tolerance level to pressure pain in the index finger as well as grip strength and neck mobility was reduced compared with controls . The whiplash patients showed poorer mental well-being compared with a reference group representing the general population and compared with a group of tension-type headache patients Background In this preliminary trial we investigated the effects of dry cupping , an ancient method for treating pain syndromes , on patients with chronic non-specific neck pain . Sensory mechanical thresholds and the participants ' self-reported outcome measures of pain and quality of life were evaluated . Methods Fifty patients ( 50.5 ± 11.9 years ) were r and omised to a  treatment group ( TG ) or a waiting-list control group ( WL ) . Patients in the TG received a series of 5 cupping treatments over a period of 2 weeks ; the control group did not . Self-reported outcome measures before and after the cupping series included the following : Pain at rest ( PR ) and maximal pain related to movement ( PM ) on a 100-mm visual analogue scale ( VAS ) , pain diary ( PD ) data on a 0 - 10 numeric rating scale ( NRS ) , Neck Disability Index ( NDI ) , and health-related quality of life ( SF-36 ) . In addition , the mechanical-detection thresholds ( MDT ) , vibration-detection thresholds ( VDT ) , and pressure-pain thresholds ( PPT ) were determined at pain-related and control areas . Results Patients of the TG had significantly less pain after cupping therapy than patients of the WL group ( PR : Δ-22.5 mm , p = 0.00002 ; PM : Δ-17.8 mm , p = 0.01 ) . Pain diaries ( PD ) revealed that neck pain decreased gradually in the TG patients and that pain reported by the two groups differed significantly after the fifth cupping session ( Δ-1.1 , p = 0 
    Output:
    
Our study indicates either that pain threshold is a poor marker of central sensitization or that sensitization does not play a major role in patients ' reporting of pain and disability .