***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: Objective : To vali date and refine two sets of c and i date criteria for the classification/diagnosis of axial spondyloarthritis ( SpA ) . Methods : All Assessment of SpondyloArthritis international Society ( ASAS ) members were invited to include consecutively new patients with chronic ( ⩾3 months ) back pain of unknown origin that began before 45 years of age . The c and i date criteria were first tested in the entire cohort of 649 patients from 25 centres , and then refined in a r and om selection of 40 % of cases and thereafter vali date d in the remaining 60 % . Results : Upon diagnostic work-up , axial SpA was diagnosed in 60.2 % of the cohort . Of these , 70 % did not fulfil modified New York criteria and , therefore , were classified as having “ non-radiographic ” axial SpA. Refinement of the c and i date criteria result ed in new ASAS classification criteria that are defined as : the presence of sacroiliitis by radiography or by magnetic resonance imaging ( MRI ) plus at least one SpA feature ( “ imaging arm ” ) or the presence of HLA-B27 plus at least two SpA features ( “ clinical arm ” ) . The sensitivity and specificity of the entire set of the new criteria were 82.9 % and 84.4 % , and for the imaging arm alone 66.2 % and 97.3 % , respectively . The specificity of the new criteria was much better than that of the European Spondylarthropathy Study Group criteria modified for MRI ( sensitivity 85.1 % , specificity 65.1 % ) and slightly better than that of the modified Amor criteria ( sensitivity 82.9 , specificity 77.5 % ) . Conclusion : The new ASAS classification criteria for axial SpA can reliably classify patients for clinical studies and may help rheumatologists in clinical practice in diagnosing axial SpA in those with chronic back pain . Trial registration number : NCT00328068 Study Design . In 151 adult patients with ankylosing spondylitis who participated in an inpatient rehabilitation program of 3–4 weeks , 10 different range of motion  ( ROM ) values were measured , and their lumbar spine and sacroiliac joints were radiographed . Objectives . To determine whether a correlation obtained between restriction of ROM and progression of radiologic findings in ankylosing spondylitis , together with a high enough reliability level in measurements . Summary of Background Data . A significant correlation was observed between the restriction of eight ROMs : the  Schober test , thoracolumbar rotation , thoracolumbar flexion , cervical rotation , occiput-wall distance , chin-chest distance , chest expansion , finger-floor distance , and overall radiologic changes in both lumbar spine and sacroiliac joints ; straight leg raise did not correlate , and vital capacity only with sacroiliac joint changes . Spearman 's correlation coefficients for ROMs were slightly higher to lumbar spine changes than to sacroiliac joint changes . A corresponding correlation was also observed between spinal mobility restrictions and six detailed changes in lumbar roentgenogram : syndesmophytes , apophyseal arthritis , sclerotic anterior borders of vertebrae , straightened anterior surface of vertebrae , and ossification of interspinous and anterior longitudinal ligaments . Other detailed lumbar spine findings did not correlate . As assessed by erythrocyte sedimentation rate values the disease activity increased in the course of radiologic progression , decreasing again , however , to the end stage . Methods . Conventional methods with a tape and ( Myrin ) inclinometer were used to measure thoracolumbar flexion , cervical rotation , occiput-wall distance , chin-chest distance , finger-floor distance , chest expansion , vital capacity , and straight leg raise . In addition , a new method of thoracolumbar rotation and a new modification of the Schober test were introduced . Thirty-nine patients were r and omized for a reliability assessment using repeated measurements of ROMs . Radiologic changes were evaluated ( in a masked fashion ) using the method of Dale and Vinje . Results . The reliability of all ROMs was good ( except for interraler intraclass correlation coefficients of chest expansion : 0.53 ) . Conclusions : The clear correlation between radiologic sacroiliac joint and lumbar spine progression and eight ROMs showed that these are useful noninvasive measurements of disease progression and severity in ankylosing spondylitis that can be used in daily practice OBJECTIVE To evaluate a magnetic resonance imaging ( MRI ) scoring system for the assessment of spinal inflammation in patients with ankylosing spondylitis ( AS ) who participated in a r and omized , placebo-controlled trial of infliximab  , and to examine whether infliximab is also effective for the reduction of MRI-proven spinal inflammation . METHODS Twenty patients with AS ( 9 women and 11 men , mean age 40.9 years ) were examined at baseline and after 3 months . Nine patients had received infusions of infliximab ( 5 mg/kg body weight ) at weeks 0 , 2 , and 6 , and 11 patients had received placebo . Three MRI sequences and 2 scoring systems were used . Chronic lesions were evaluated by T1-weighted turbo spin-echo ( TSE ) sequences and were assigned a chronicity score . Active lesions were evaluated either by repetition of T1-weighted TSE sequences after infusion of gadolinium-diethylenetriaminepentaacetic acid ( Gd-DTPA ) or by short tau inversion recovery ( STIR ) sequences , and were assigned an activity score . The 40 images were evaluated twice by 2 readers who were blinded to the names of the patients and the date s of the examinations , and were analyzed in relation to the clinical results . RESULTS Active spinal lesions were detected in 15 of 20 patients ( 75 % ) ; the frequency as determined by STIR was equal in the 2 groups . At baseline , the total MRI scores determined using Gd-DTPA , STIR , and T1 were 112.5 , 156 , and 253.5 , respectively . The interrater variance and intrarater variance were , respectively , 6.4 and 7.7 for the active lesion score as determined by Gd-DTPA , 15.7 and 5.3 for the active lesion score as determined by STIR sequence , and 167.3 and 75.5 for the chronic lesion score as determined by T1 sequence . Based on the means of the scores assigned by the 2 readers , the active lesion score as determined by Gd-DTPA improved by 40 % in the infliximab group compared with 6 % in the placebo group , the active lesion score as determined by STIR improved by 60 % in the infliximab group but deteriorated by 21 % in the placebo group , and the chronic lesion score as determined by T1 improved by 7 % in the infliximab group but worsened by 35 % in the placebo group . Five patients in the infliximab group and 2 in the placebo group were clinical responders . The acute MRI changes correlated with clinical improvement as assessed by the Bath Ankylosing Spondylitis Disease Activity Index . CONCLUSION This novel MRI scoring system performed well in assessing acute inflammation by using STIR and post-Gd-DTPA sequences . In correlation with clinical improvement in patients with active AS who were treated with infliximab , significant regression of spinal inflammation was shown by using the MRI activity scores OBJECTIVE To develop a reproducible and simple radiologic scoring system for the spine in patients with ankylosing spondylitis ( AS ) : the Bath Ankylosing Spondylitis Radiology Index for the spine ( BASRI-s ) . METHODS  Radiographs of 470 patients with AS were scored using the New York criteria for the sacroiliac joints and , similarly , grading the lumbar and cervical spine on a scale of 0 - 4 ( for normal , suspicious , mild , moderate , and severe ) . These 3 scores were added together to produce the BASRI-s score ( scored 2 - 12 ) . Radiographs of 188 patients were used to test reproducibility . Blinded radiographs of 89 non-AS patients were included , r and omly , to assess disease specificity . Sensitivity to change was assessed using 177 radiographs from 58 AS patients . RESULTS Intra- and interobserver variation showed 75 - 86 % and 73 - 79 % complete agreement at all sites , respectively . Specificities of 0.83 - 0.89 suggested that the lumbar and cervical spine BASRI scores were disease specific . Sensitivity to change became apparent at 2 years ( P < 0.001 ) . Using a lateral view and an anteroposterior view of the lumbar spine was more sensitive than using a lateral view alone . Grading a set of radiographs ( sacroiliac joints , lumbar spine , and cervical spine ) took 30 seconds . CONCLUSION BASRI is a reliable method for grading radiographic changes in patients with AS . It is disease specific , sensitive to change , valid , simple , and rapid to perform OBJECTIVE To evaluate the role of MRI in predicting a Bath Ankylosing Spondylitis Disease Activity Index ( BASDAI ) improvement of at least 50 % ( BASDAI 50 ) upon anti-tumour necrosis factor ( TNF ) therapy of active ankylosing spondylitis ( AS ) . METHODS  MRIs from patients with active AS who participated in r and omised controlled trials were analysed with respect to presence and extent of active inflammatory lesions as detected in the spine ( n = 46 ) , sacroiliac ( SI ) joints ( n = 42 ) and both sites ( n = 26 ) . Univariate and multivariate logistic regression analyses were applied to evaluate MRI and clinical data in predicting a BASDAI 50 response . RESULTS The Berlin MRI spine score ( odds ratio ( OR ) 1.16 , 95 % CI 1.02 to 1.33 ) and disease duration ( OR 0.9 , 95 % CI 0.63 to 0.97 ) were statistically significant predictors of a BASDAI 50 response using regression analysis while there was only a trend for C-reactive protein ( CRP ) . The likelihood ratio ( LR ) for achievement of BASDAI 50 was increased in patients with a Berlin MRI spine score > /=11 ( LR 6.7 ) , disease duration < 10 years ( LR 4.2 ) and CRP > /=40 mg/litre ( LR 3.4 ) . All patients with two or three of these predictors improved clinical ly ( as assessed by BASDAI ) by at least 45 % . Disease duration > 20 years , normal CRP and no active inflammatory lesion in the spine were highly predictive of not achieving BASDAI 50 . A trend was only found for the MRI score of SI joints to be predictive . CONCLUSIONS Widespread inflammation in the spine as detected by MRI contributes to predicting a BASDAI 50 response in active patients with AS treated with anti-TNF agents Objective To study the relationship between spinal mobility , radiographic damage of the spine and spinal inflammation as assessed by MRI in patients with ankylosing spondylitis ( AS ) . Methods In this sub analysis of the Ankylosing Spondylitis Study for the Evaluation of Recombinant Infliximab Therapy cohort , 214 patients , representing an 80 % r and om sample , were investigated . Only baseline data were used . MRI inflammation was assessed by the AS spinal MRI activity ( ASspiMRI-a ) score , structural damage by the modified Stoke AS Spine Score ( mSASSS ) and spinal mobility by the linear definition of the Bath Ankylosing Spondylitis Metrology Index ( BASMI ) . Univariate correlations were calculated on baseline values using Spearman rank correlation . Independent associations between the variables of interest were investigated by multivariate linear regression analysis . Associations with clinical disease activity , C-reactive protein , disease duration , age , gender , body mass index and HLA-B27 status were also investigated . Subanalyses were performed according to disease duration . Results BASMI correlated moderately well with mSASSS ( Spearman 's ρ=0.6 ) and weakly with ASspiMRI-a ( ρ=0.3 ) . A best-fit model for BASMI included both mSASSS ( regression coefficient (B)=0.865 , p<0.001 ) and ASspiMRI-a ( B=0.236 , p=0.018 ) . In patients with a disease duration ≤3 years , B was greater for ASspiMRI-a than for mSASSS ( 0.595 vs 0.380 ) , while in patients with a disease duration > 3 years B was greater for mSASSS than for ASspiMRI-a ( 0.924 vs 0.156 ) . Conclusion Spinal mobility impairment in AS is independently determined both by irreversible spinal damage and by reversible spinal inflammation . Spinal mobility impairment is more influenced by spinal inflammation in early disease , and by structural damage in later disease Study Design . A prospect i ve , controlled clinical study performed in a tertiary care center . Objective . To determine reliability and validity of low-tech measurements in assessment of range of motion ( ROM ) of lumbar flexion in ankylosing spondylitis ( AS ) . Summary of Background Data . ROM measurements of lumbar flexion in patients with AS and healthy subjects are evaluated using original Schober test ( OST ) , modified Schober index ( MSI ) , and modified-modified Schober test ( MMST ) and compared with radiography . Methods . Fifty patients with AS and  
    Output:
    
Spinal mobility measures do not reflect levels of inflammation at either the sacroiliac joints and /or the spine