human
***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 effect of  low back pain , with or without nerve root signs , on the joint coordination and kinematics of the lumbar spine and hips during everyday activities , such as picking up an object from the floor , are largely unknown . An experimental study was design ed to compare lumbar spine and hip joint kinematics and coordination in subjects with and without sub-acute low back pain , while picking up an object in a sitting position . A three-dimensional real-time electromagnetic tracking device was used to measure movements of the lumbar spine and hips . Sixty participants with subacute low back pain , with or without straight leg raise signs , and twenty healthy asymptomatic participants were recruited . The ranges of motions of lumbar spine and hips were determined . Movement coordination between the two regions was examined by cross-correlation . Results showed that mobility was significantly reduced in subjects with back pain , who compensated for limited motion through various strategies . The contribution of the lumbar spine relative to that of the hip was , however , found to be similar in all groups . The lumbar spine – hip joint coordination was substantially altered in subjects with back pain , in particular , those with a positive straight leg raise sign . We conclude that changes in the lumbar and hip kinematics were related to back pain and limitation in straight leg raise . Lumbar – hip coordination was mainly affected by the presence of positive straight leg raise sign when picking up an object in a sitting position This study investigated whether people with low back pain ( LBP ) reduce variability of movement between the pelvis and thorax ( trunk ) in the transverse plane during gait at different speeds compared to healthy controls . Thirteen people with chronic LBP and twelve healthy controls  walked on a treadmill  at speeds from 0.5 to 1.72 m/s , with increments of 0.11 m/s . Step-to-step variability of the trunk , pelvis , and thorax rotations were calculated . Step-to-step deviations of pelvis and thorax rotations from the average pattern ( residual rotations ) were correlated to each other , and the linear regression coefficients between these deviations calculated . Spectral analysis was used to determine the frequencies of the residual rotations , to infer the relation of reduced trunk variability to trunk stiffness and /or damping . Variability of trunk motion ( thorax relative to pelvis ) was lower ( P=0.02 ) , covariance between the residual rotations of pelvis and thorax motions was higher ( P=0.03 ) , and the linear regression coefficients were closer to 1 ( P=0.05 ) in the LBP group . Most power of segmental residual rotations was below stride frequency ( ~1 Hz ) . In this frequency range , trunk residual rotations had less power than pelvis or thorax residual rotations . These data show that people with LBP had lower variability of trunk rotations , as a result of the coupling of deviations of residual rotations in one segment to deviations of a similar shape ( correlation ) and amplitude ( regression coefficient ) in the other segment . These results support the argument that people with LBP adopt a protective movement strategy , possibly by increased trunk stiffness The reported association of low-back pain and musculoskeletal disorders contributed to the examination of the lumbar spine and hip extensor activation patterns in back pain sufferers during walking . Seventeen idiopathic low-back pain male subjects and 16 healthy volunteers participated in the study .  Hip joint ROMs in the sagittal plane and neuromuscular activities of erector spinae [ L3 , T12 ] , gluteus maximus and biceps femoris were recorded on one r and omly selected body side in each group . Analysis using the Student 's t-test revealed significant differences for hip joint range of motion , stride time and significantly earlier onsets of the lumbar spine and hip extensors of the back pain sufferers compared with the healthy controls . It is assumed , that low-back disorders are related to changes of the lumbar spine and hip extensor recruitment pattern Study Design . A prospect i ve study was conducted on a group of patients with unilateral nonspecific low back pain ( LBP ) and healthy controls . Objectives . To answer 3 questions : ( 1 ) Does pelvic asymmetry measured in st and ing affect the dynamics of motion performed in sitting ? ( 2 ) Do patients with LBP perform trunk motions differently from non-LBP participants in sitting position ? and ( 3 ) Do the kinematics of lateral flexion and axial rotation differ between sitting and st and ing positions ? Summary of Background Data . The effect of pelvic asymmetry on trunk motion while sitting remains unclear . LBP has been associated with altered trunk kinematics in st and ing ; however , there is limited information available describing trunk kinematics in sitting position in comparison to st and ing . Methods . Pelvic asymmetry was measured in 54 patients with unilateral nonspecific LBP and 59 control subjects .  A motion- analysis system was used to test the  range and symmetry of lateral flexion and axial rotation  in sitting and st and ing positions . Bivariate correlations , regression , multivariate analysis of variance , and paired sample t tests were used to test for associations between variables and differences between groups . Results . We found significant : ( 1 ) correlations between pelvic asymmetry and asymmetric trunk motion performed in sitting , ( 2 ) differences between the LBP and control groups in patterns of trunk motion performed in a sitting posture , and ( 3 ) differences between kinematics of motions performed in sitting versus st and ing postures . Conclusions . This study shows a link between pelvic asymmetry and altered trunk motion in sitting position . We suggest that people with LBP may have a distinct compensatory mechanism , secondary to pelvic asymmetry , which puts the lumbar spine under higher stress . Movement asymmetry , rather than range of motion , may be a better indicator of disturbed function for people with LBP . Structural and functional asymmetries are factors that may be considered in the seating design and work environment Study Design . Classification and functional assessment model for nonspecific low back pain ( LBP ) patients and controls on the basis of kinematic analysis parameters . Objective . Develop a logistic regression model using kinematic analysis variables to ( 1 ) discriminate between LBP patients and controls and ( 2 ) obtain objective parameters for LBP functional assessment . Summary of Background Data . Functional assessment of spinal disorders has been carried out traditionally by means of subjective scales . Objective functional techniques have been developed , which usually involve the application of external loads or the analysis of highly st and ardized trunk flexion-extension maneuvers . Few studies have used everyday activities such as sit-to-st and or lifting an object from the ground . They have shown that the motion patterns of LBP patients differ from those of healthy subjects . Nevertheless , very few studies have tried to correlate objective findings to the results of subjective scales , and no previous study has developed a LBP classification and functional assessment model on the basis of kinematic analysis of everyday activities . Methods . Sixteen controls and 39 LBP patients performed a sit-to-st and task , and lifted three different weights from a st and ing position . The vertical forces exerted and the relative positions of the lower limb and the cervical , thoracic , lumbar , and sacroiliac regions were recorded . Reliability was determined from repetitions of the tests performed by the control group . Binary logistic regression analyses were computed . The results of the selected regression equation were correlated to the Oswestry Disability Index scale results , to check the validity of the procedure for the measurement of functional disability . Results . Reliability of the parameters was good . The selected regression model used two variables , and correctly classified 97.3 % of the patients . High correlations were found between the results of this regression equation and the Oswestry Disability Index scale . Conclusion . It is possible to distinguish LBP patients from healthy subjects by means of the biomechanical analysis of everyday tasks . This kind of analysis can produce objective and reliable indexes about the patients ' degree of functional impairment Background obesity is nowadays a p and emic condition . Obese subjects are commonly characterized by musculoskeletal disorders and particularly by non-specific chronic low back pain ( cLBP ) . However , the relationship between obesity and cLBP remains to date unsupported by an objective measurement of the mechanical behaviour of the spine and its morphology in obese subjects . Such analysis may provide a deeper underst and ing of the relationships between function and the onset of clinical symptoms . Purpose to objective ly assess the posture and function of the spine during st and ing , flexion and lateral bending in obese subjects with and without cLBP and to investigate the role of obesity in cLBP . Study design Cross-sectional study Patient sample thirteen obese subjects , thirteen obese subjects with cLBP , and eleven healthy subjects were enrolled in this study . Outcome measures we evaluated the outcome in terms of angles at the initial st and ing position ( START ) and at maximum forward flexion ( MAX ) . The range of motion ( ROM ) between START and MAX was also computed . Methods we studied forward flexion and lateral bending of the spine using an optoelectronic system and passive retroreflective markers applied on the trunk . A biomechanical model was developed in order to analyse kinematics and define angles of clinical interest . Results obesity was characterized by a generally reduced ROM of the spine , due to a reduced mobility at both pelvic and thoracic level ; a static postural adaptation with an increased anterior pelvic tilt . Obesity with cLBP is associated with an increased lumbar lordosis . In lateral bending , obesity with cLBP is associated with a reduced ROM of the lumbar and thoracic spine , whereas obesity on its own appears to affect only the thoracic curve . Conclusions obese individuals with cLBP showed higher degree of spinal impairment when compared to those without cLBP . The observed obesity-related thoracic stiffness may characterize this sub-group of patients , even if prospect i ve studies should be carried out to verify this hypothesis OBJECTIVE : To test the feasibility of creating a valid and reliable checklist with the following features : appropriate for assessing both r and omised and non-r and omised studies ; provision of both an overall score for study quality and a profile of scores not only for the quality of reporting , internal validity ( bias and confounding ) and power , but also for external validity . DESIGN : A pilot version was first developed , based on epidemiological principles , review s , and existing checklists for r and omised studies . Face and content validity were assessed by three experienced review ers and reliability was determined using two raters assessing 10 r and omised and 10 non-r and omised studies . Using different raters , the checklist was revised and tested for internal consistency ( Kuder-Richardson 20 ) , test-retest and inter-rater reliability ( Spearman correlation coefficient and sign rank test ; kappa statistics ) , criterion validity , and respondent burden . MAIN RESULTS : The performance of the checklist improved considerably after revision of a pilot version . The Quality Index had high internal consistency ( KR-20 : 0.89 ) as did the subscales apart from external validity ( KR-20 : 0.54 ) . Test-retest ( r 0.88 ) and inter-rater ( r 0.75 ) reliability of the Quality Index were good . Reliability of the subscales varied from good ( bias ) to poor ( external validity ) . The Quality Index correlated highly with an existing , established instrument for assessing r and omised studies ( r 0.90 ) . There was little difference between its performance with non-r and omised and with r and omised studies . Raters took about 20 minutes to assess each paper ( range 10 to 45 minutes ) . CONCLUSIONS : This study has shown that it is feasible to develop a checklist that can be used to assess the method ological quality not only of r and omised controlled trials but also non-r and omised studies . It has also shown that it is possible to produce a checklist that provides a profile of the paper , alerting review ers to its particular method ological strengths and weaknesses . Further work is required to improve the checklist and the training of raters in the assessment of external validity BACKGROUND AND PURPOSE Little is known about how acute low back pain affects pelvic and lumbar movements during walking . The aim of the present study was to determine if measurement of the amplitude of the  angular movements of the pelvis and lumbar spine during walking is useful in the evaluation of people with acute low back pain . METHOD The study used a repeated- measures and correlational design ; 11 individuals with low back pain ( tested in the acute phase and six weeks later when symptoms had resolved ) and matched control subjects were tested during treadmill walking . A video- analysis system was used to measure the amplitudes of movements of the pelvis and lumbar spine during walking .  Pain level was measured with a visual analogue scale ( VAS ) . RESULTS During walking , movements of the pelvis ( axial rotation ) and lumbar spine ( lateral flexion ) were reduced in people with acute back pain compared with the resolved condition , but were not different from a group without a history of back pain . The amplitudes of the frontal plane movements of the pelvis and lumbar spine were negatively correlated with the intensity of pain ( r(s ) = -0.74 ) . CONCLUSIONS Measurement of pelvic and lumbar movements during walking is unlikely to have useful clinical applications for individuals , or when discriminating between impaired and unimpaired people , but may be applied to groups for hypothesis testing in evaluating change in back pain over time . An hypothesized model to explain the observed movements has been proposed BACKGROUND Although the effect of symptomatic back pain on functional movement has been investigated , changes to spinal movement patterns in essentially pain-free people with a history of recurrent back pain are largely unreported . Reaching activities , important for everyday and occupational function , often present problems to such people , but have not been considered in this population . The purpose of this study was to compare the amplitude and timing of spinal and hip  motions  during two , seated reaching activities in people with and without a history of recurrent low back pain ( RLBP ) . METHODS  Spinal and hip motions during reaching downward and across the body , in both directions , were tracked using electromagnetic sensors . Analyses were conducted to explore the amplitudes , velocities and timings of 3D segmental movements and to compare controls with subjects with recurrent , but asymptomatic lumbar or lumbosacral pain . FIND 
    Output:
    
agent
The most commonly reported outcome was range of motion .
Interpretation : The literature to date offers limited and inconsistent evidence of kinematic/kinetic measures in low back pain patients that could be used clinical ly .
HighlightsCurrent low back pain assessment relies on subjective measures .Use of objective measures ( kinematics/kinetics ) is encouraged in low back pain assessment .This review highlights the heterogeneity of studies with low back pain and healthy subjects .
***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 effect of  low back pain , with or without nerve root signs , on the joint coordination and kinematics of the lumbar spine and hips during everyday activities , such as picking up an object from the floor , are largely unknown . An experimental study was design ed to compare lumbar spine and hip joint kinematics and coordination in subjects with and without sub-acute low back pain , while picking up an object in a sitting position . A three-dimensional real-time electromagnetic tracking device was used to measure movements of the lumbar spine and hips . Sixty participants with subacute low back pain , with or without straight leg raise signs , and twenty healthy asymptomatic participants were recruited . The ranges of motions of lumbar spine and hips were determined . Movement coordination between the two regions was examined by cross-correlation . Results showed that mobility was significantly reduced in subjects with back pain , who compensated for limited motion through various strategies . The contribution of the lumbar spine relative to that of the hip was , however , found to be similar in all groups . The lumbar spine – hip joint coordination was substantially altered in subjects with back pain , in particular , those with a positive straight leg raise sign . We conclude that changes in the lumbar and hip kinematics were related to back pain and limitation in straight leg raise . Lumbar – hip coordination was mainly affected by the presence of positive straight leg raise sign when picking up an object in a sitting position This study investigated whether people with low back pain ( LBP ) reduce variability of movement between the pelvis and thorax ( trunk ) in the transverse plane during gait at different speeds compared to healthy controls . Thirteen people with chronic LBP and twelve healthy controls  walked on a treadmill  at speeds from 0.5 to 1.72 m/s , with increments of 0.11 m/s . Step-to-step variability of the trunk , pelvis , and thorax rotations were calculated . Step-to-step deviations of pelvis and thorax rotations from the average pattern ( residual rotations ) were correlated to each other , and the linear regression coefficients between these deviations calculated . Spectral analysis was used to determine the frequencies of the residual rotations , to infer the relation of reduced trunk variability to trunk stiffness and /or damping . Variability of trunk motion ( thorax relative to pelvis ) was lower ( P=0.02 ) , covariance between the residual rotations of pelvis and thorax motions was higher ( P=0.03 ) , and the linear regression coefficients were closer to 1 ( P=0.05 ) in the LBP group . Most power of segmental residual rotations was below stride frequency ( ~1 Hz ) . In this frequency range , trunk residual rotations had less power than pelvis or thorax residual rotations . These data show that people with LBP had lower variability of trunk rotations , as a result of the coupling of deviations of residual rotations in one segment to deviations of a similar shape ( correlation ) and amplitude ( regression coefficient ) in the other segment . These results support the argument that people with LBP adopt a protective movement strategy , possibly by increased trunk stiffness The reported association of low-back pain and musculoskeletal disorders contributed to the examination of the lumbar spine and hip extensor activation patterns in back pain sufferers during walking . Seventeen idiopathic low-back pain male subjects and 16 healthy volunteers participated in the study .  Hip joint ROMs in the sagittal plane and neuromuscular activities of erector spinae [ L3 , T12 ] , gluteus maximus and biceps femoris were recorded on one r and omly selected body side in each group . Analysis using the Student 's t-test revealed significant differences for hip joint range of motion , stride time and significantly earlier onsets of the lumbar spine and hip extensors of the back pain sufferers compared with the healthy controls . It is assumed , that low-back disorders are related to changes of the lumbar spine and hip extensor recruitment pattern Study Design . A prospect i ve study was conducted on a group of patients with unilateral nonspecific low back pain ( LBP ) and healthy controls . Objectives . To answer 3 questions : ( 1 ) Does pelvic asymmetry measured in st and ing affect the dynamics of motion performed in sitting ? ( 2 ) Do patients with LBP perform trunk motions differently from non-LBP participants in sitting position ? and ( 3 ) Do the kinematics of lateral flexion and axial rotation differ between sitting and st and ing positions ? Summary of Background Data . The effect of pelvic asymmetry on trunk motion while sitting remains unclear . LBP has been associated with altered trunk kinematics in st and ing ; however , there is limited information available describing trunk kinematics in sitting position in comparison to st and ing . Methods . Pelvic asymmetry was measured in 54 patients with unilateral nonspecific LBP and 59 control subjects .  A motion- analysis system was used to test the  range and symmetry of lateral flexion and axial rotation  in sitting and st and ing positions . Bivariate correlations , regression , multivariate analysis of variance , and paired sample t tests were used to test for associations between variables and differences between groups . Results . We found significant : ( 1 ) correlations between pelvic asymmetry and asymmetric trunk motion performed in sitting , ( 2 ) differences between the LBP and control groups in patterns of trunk motion performed in a sitting posture , and ( 3 ) differences between kinematics of motions performed in sitting versus st and ing postures . Conclusions . This study shows a link between pelvic asymmetry and altered trunk motion in sitting position . We suggest that people with LBP may have a distinct compensatory mechanism , secondary to pelvic asymmetry , which puts the lumbar spine under higher stress . Movement asymmetry , rather than range of motion , may be a better indicator of disturbed function for people with LBP . Structural and functional asymmetries are factors that may be considered in the seating design and work environment Study Design . Classification and functional assessment model for nonspecific low back pain ( LBP ) patients and controls on the basis of kinematic analysis parameters . Objective . Develop a logistic regression model using kinematic analysis variables to ( 1 ) discriminate between LBP patients and controls and ( 2 ) obtain objective parameters for LBP functional assessment . Summary of Background Data . Functional assessment of spinal disorders has been carried out traditionally by means of subjective scales . Objective functional techniques have been developed , which usually involve the application of external loads or the analysis of highly st and ardized trunk flexion-extension maneuvers . Few studies have used everyday activities such as sit-to-st and or lifting an object from the ground . They have shown that the motion patterns of LBP patients differ from those of healthy subjects . Nevertheless , very few studies have tried to correlate objective findings to the results of subjective scales , and no previous study has developed a LBP classification and functional assessment model on the basis of kinematic analysis of everyday activities . Methods . Sixteen controls and 39 LBP patients performed a sit-to-st and task , and lifted three different weights from a st and ing position . The vertical forces exerted and the relative positions of the lower limb and the cervical , thoracic , lumbar , and sacroiliac regions were recorded . Reliability was determined from repetitions of the tests performed by the control group . Binary logistic regression analyses were computed . The results of the selected regression equation were correlated to the Oswestry Disability Index scale results , to check the validity of the procedure for the measurement of functional disability . Results . Reliability of the parameters was good . The selected regression model used two variables , and correctly classified 97.3 % of the patients . High correlations were found between the results of this regression equation and the Oswestry Disability Index scale . Conclusion . It is possible to distinguish LBP patients from healthy subjects by means of the biomechanical analysis of everyday tasks . This kind of analysis can produce objective and reliable indexes about the patients ' degree of functional impairment Background obesity is nowadays a p and emic condition . Obese subjects are commonly characterized by musculoskeletal disorders and particularly by non-specific chronic low back pain ( cLBP ) . However , the relationship between obesity and cLBP remains to date unsupported by an objective measurement of the mechanical behaviour of the spine and its morphology in obese subjects . Such analysis may provide a deeper underst and ing of the relationships between function and the onset of clinical symptoms . Purpose to objective ly assess the posture and function of the spine during st and ing , flexion and lateral bending in obese subjects with and without cLBP and to investigate the role of obesity in cLBP . Study design Cross-sectional study Patient sample thirteen obese subjects , thirteen obese subjects with cLBP , and eleven healthy subjects were enrolled in this study . Outcome measures we evaluated the outcome in terms of angles at the initial st and ing position ( START ) and at maximum forward flexion ( MAX ) . The range of motion ( ROM ) between START and MAX was also computed . Methods we studied forward flexion and lateral bending of the spine using an optoelectronic system and passive retroreflective markers applied on the trunk . A biomechanical model was developed in order to analyse kinematics and define angles of clinical interest . Results obesity was characterized by a generally reduced ROM of the spine , due to a reduced mobility at both pelvic and thoracic level ; a static postural adaptation with an increased anterior pelvic tilt . Obesity with cLBP is associated with an increased lumbar lordosis . In lateral bending , obesity with cLBP is associated with a reduced ROM of the lumbar and thoracic spine , whereas obesity on its own appears to affect only the thoracic curve . Conclusions obese individuals with cLBP showed higher degree of spinal impairment when compared to those without cLBP . The observed obesity-related thoracic stiffness may characterize this sub-group of patients , even if prospect i ve studies should be carried out to verify this hypothesis OBJECTIVE : To test the feasibility of creating a valid and reliable checklist with the following features : appropriate for assessing both r and omised and non-r and omised studies ; provision of both an overall score for study quality and a profile of scores not only for the quality of reporting , internal validity ( bias and confounding ) and power , but also for external validity . DESIGN : A pilot version was first developed , based on epidemiological principles , review s , and existing checklists for r and omised studies . Face and content validity were assessed by three experienced review ers and reliability was determined using two raters assessing 10 r and omised and 10 non-r and omised studies . Using different raters , the checklist was revised and tested for internal consistency ( Kuder-Richardson 20 ) , test-retest and inter-rater reliability ( Spearman correlation coefficient and sign rank test ; kappa statistics ) , criterion validity , and respondent burden . MAIN RESULTS : The performance of the checklist improved considerably after revision of a pilot version . The Quality Index had high internal consistency ( KR-20 : 0.89 ) as did the subscales apart from external validity ( KR-20 : 0.54 ) . Test-retest ( r 0.88 ) and inter-rater ( r 0.75 ) reliability of the Quality Index were good . Reliability of the subscales varied from good ( bias ) to poor ( external validity ) . The Quality Index correlated highly with an existing , established instrument for assessing r and omised studies ( r 0.90 ) . There was little difference between its performance with non-r and omised and with r and omised studies . Raters took about 20 minutes to assess each paper ( range 10 to 45 minutes ) . CONCLUSIONS : This study has shown that it is feasible to develop a checklist that can be used to assess the method ological quality not only of r and omised controlled trials but also non-r and omised studies . It has also shown that it is possible to produce a checklist that provides a profile of the paper , alerting review ers to its particular method ological strengths and weaknesses . Further work is required to improve the checklist and the training of raters in the assessment of external validity BACKGROUND AND PURPOSE Little is known about how acute low back pain affects pelvic and lumbar movements during walking . The aim of the present study was to determine if measurement of the amplitude of the  angular movements of the pelvis and lumbar spine during walking is useful in the evaluation of people with acute low back pain . METHOD The study used a repeated- measures and correlational design ; 11 individuals with low back pain ( tested in the acute phase and six weeks later when symptoms had resolved ) and matched control subjects were tested during treadmill walking . A video- analysis system was used to measure the amplitudes of movements of the pelvis and lumbar spine during walking .  Pain level was measured with a visual analogue scale ( VAS ) . RESULTS During walking , movements of the pelvis ( axial rotation ) and lumbar spine ( lateral flexion ) were reduced in people with acute back pain compared with the resolved condition , but were not different from a group without a history of back pain . The amplitudes of the frontal plane movements of the pelvis and lumbar spine were negatively correlated with the intensity of pain ( r(s ) = -0.74 ) . CONCLUSIONS Measurement of pelvic and lumbar movements during walking is unlikely to have useful clinical applications for individuals , or when discriminating between impaired and unimpaired people , but may be applied to groups for hypothesis testing in evaluating change in back pain over time . An hypothesized model to explain the observed movements has been proposed BACKGROUND Although the effect of symptomatic back pain on functional movement has been investigated , changes to spinal movement patterns in essentially pain-free people with a history of recurrent back pain are largely unreported . Reaching activities , important for everyday and occupational function , often present problems to such people , but have not been considered in this population . The purpose of this study was to compare the amplitude and timing of spinal and hip  motions  during two , seated reaching activities in people with and without a history of recurrent low back pain ( RLBP ) . METHODS  Spinal and hip motions during reaching downward and across the body , in both directions , were tracked using electromagnetic sensors . Analyses were conducted to explore the amplitudes , velocities and timings of 3D segmental movements and to compare controls with subjects with recurrent , but asymptomatic lumbar or lumbosacral pain . FIND 
    Output:
    