Differences in end-range lumbar flexion during slumped sitting and forward bending between low back pain subgroups and genders

Management of Low Back Pain With Concurrent Hamstring Tightness: A Case Report Highlighting the Efficacy of Proprioceptive Neuromuscular Facilitation, Mulligan's Two-Leg Rotation Technique, and Exercise Regimen

Low back pain (LBP) is a prevalent musculoskeletal issue characterized by discomfort in the lumbosacral region. LBP localized between the 12th thoracic vertebra and inferior gluteal folds is common and often lacks a clear etiology. Various factors contribute to LBP, including increased lumbar lordosis, diminished abdominal muscle strength, reduced back extensor muscle endurance, and flexibility limitations in the back extensors, iliopsoas, and hamstrings. Treatment modalities for LBP encompass surgical intervention, pharmacotherapy, lumbar injections, psychotherapy, chiropractic care, and physiotherapy, with manual therapy being a prominent approach. Physiotherapists employ a spectrum of manual techniques, including mobilization, manipulation, and massage, to address LBP. Hamstring flexibility plays a pivotal role in spinal mechanics, and tight or shortened hamstrings can exacerbate LBP. Mulligan's techniques, notably the two-leg rotation (TLR) technique, are valuable interventions for addressing hamstring tightness in cases of LBP. Proprioceptive neuromuscular facilitation (PNF) was also used to manage pain and improve strength. This case report outlines the management of a 32-year-old male presenting with LBP and hamstring tightness coupled with core muscle weakness. Through comprehensive assessment and physiotherapeutic interventions, significant improvements were observed in pain intensity, lumbar range of motion, disability, straight leg raise (SLR), and core muscle strength following a three-week physiotherapy intervention.

Dynamic assessment of spine movement patterns using an RGB-D camera and deep learning

In clinical practice, functional limitations in patients with low back pain are subjectively assessed, potentially leading to misdiagnosis and prolonged pain. This paper proposes an objective deep learning (DL) markerless motion capture system that uses a red-green-blue-depth (RGB-D) camera to measure the kinematics of the spine during flexion-extension (FE) through: 1) the development and validation of a DL semantic segmentation algorithm that segments the back into four anatomical classes and 2) the development and validation of a framework that uses these segmentations to measure spine kinematics during FE. Twenty participants performed ten cycles of FE with drawn-on point markers while being recorded with an RGB-D camera. Five of these participants also performed an additional trial where they were recorded with an optical motion capture (OPT) system. The DL algorithm was trained to segment the back and pelvis into four anatomical classes: upper back, lower back, spine, and pelvis. A kinematic framework was then developed to refine these segmentations into upper spine, lower spine, and pelvis masks, which were used to measure spine kinematics after obtaining 3D global coordinates of the mask corners. The segmentation algorithm achieved high accuracy, and the root mean square error (RMSE) between ground truth and predicted lumbar kinematics was < 4°. When comparing markerless and OPT kinematics, RMSE values were < 6°. This work demonstrates the feasibility of using markerless motion capture to assess FE spine movement in clinical settings. Future work will expand the studied movement directions and test on different demographics.

Lumbar Kinematics Assessment of Patients with Chronic Low Back Pain in Three Bridge Tests Using Miniaturized Sensors

Lumbar muscle atrophy, diminished strength, stamina, and increased fatigability have been associated with chronic nonspecific low back pain (LBP). When evaluating patients with LBP, trunk or core stability, provided by the performance and coordination of trunk muscles, appears to be essential. Several clinical tests have been developed to identify deficiencies in trunk performance, demonstrating high levels of validity and reproducibility. The most frequently prescribed tests for assessing the core body muscles are the prone plank bridge test (PBT), the side bridge test (SBT), and the supine bridge test (SUBT). However, quantitative assessments of the kinematics of the lumbar spine during their execution have not yet been conducted. The purpose of our study was to provide objective biomechanical data for the assessment of LBP patients. The lumbar spine ranges of motion of 22 healthy subjects (Group A) and 25 patients diagnosed with chronic LBP (Group B) were measured using two inertial measurement units during the execution of the PBT, SUBT, and SBT. Statistically significant differences between the two groups were found in all three tests' kinematic patterns. This quantitative assessment of lumbar spine motion transforms the three bridge tests into an objective biomechanical diagnostic tool for LPBs that may be used to assess the efficacy of applied rehabilitation programs.

Influence of scapular motion cues on trapezius muscle activity during Y exercise

BACKGROUND

The Y exercise is a therapeutic exercise facilitating lower trapezius muscle activity.

OBJECTIVE

To identify the effects of scapular movement cues (posterior tilt vs. posterior tilt with adduction/depression) on trapezius muscle activity during Y exercise.

METHODS

Fifteen healthy men without current shoulder pain performed general Y exercise; Y exercise with cues for scapular posterior tilt; and Y exercise with cues for scapular posterior tilt, adduction, and depression. Electromyography (EMG) data for the trapezius muscles were collected during Y exercise. The posterior tilt angle of the scapula was measured in the prone position with and without cues for scapular posterior tilt using an inclinometer application.

RESULTS

The greatest lower trapezius muscle activity was observed during Y exercise with cues for scapular posterior tilt, while the greatest EMG activity of the upper trapezius was observed during Y exercise with cues for scapular posterior tilt, adduction, and depression (p< 0.05). Middle trapezius muscle activity did not significantly differ among the three Y exercise conditions (p= 0.175). Cues for scapular posterior tilt significantly increased the scapular posterior tilt angle in the prone shoulder abduction position (p= 0.007).

CONCLUSION

Cues for scapular posterior tilt were most effective in facilitating lower trapezius muscle activity during Y exercise.

Radiographic Investigation of Lumbar Vertebrae in Patients with Flexion and Extension Movement Disorder Syndrome

Objectives

The kinesiopathology model is a new rehabilitation model classifying, evaluating, and treating patients with non-specific back pain. Sahrmann proposed this model based on movement disorder syndromes. The present cross-sectional study aimed to evaluate the radiograph of the linear and angular displacement of the lumbar spine in patients with lumbar flexion impairment syndrome (LFIS) and lumbar extension impairment syndrome (LEIS).

Methods

In this study, 50 adults aged 18-46 years were enrolled, including 25 patients with LFIS and 25 with LEIS. The eligible participants were referred to the radiology department for radiography in the common position of neutral, full extension, and full flexion position while standing. The White and Panjabi's method was used to measure the linear and angular displacements. Moreover, pain intensity was assessed using the visual analogue scale, and functional disability was investigated using a modified Oswestry Disability Questionnaire.

Results

The parameter of the linear displacement at the L3-L4 level was significantly different between the two groups (P=0.02). The mean duration of low back pain was longer in the LEIS, compared to the LFIS group (P=0.01).

Conclusion

In patients with LEIS, compensatory responses occur that cause less linear displacement at the L3-L4 level, compared to the patients with LFIS. Therefore, it is important to design appropriate exercises to better control the linear displacement at the L3-L4 level during the full range of motion in patients with LFIS.

Segmental spine mobility differences between lumbar flexion- and extension-based movement syndromes in patients with low back pain

BACKGROUND

The Movement System Impairment (MSI) model is useful for identifying spine-hip mobility and motor control deficits that may contribute to low back pain (LBP). While previous studies have found differences in global spine-hip movement impairments between lumbar MSI subgroups, no studies have compared segmental spine movement impairments between these subgroups. Therefore, the purpose of this study is to analyze segmental lumbar mobility in participants with LBP and a lumbar flexion- or extension-based MSI.

METHODS

Forty participants with subacute-chronic LBP were placed into one of three age groups (< 35, 35-54, or > 54 years-old) and then classified into a flexion- or extension-based MSI sub-group. Segmental lumbar range of motion (ROM) was measured in degrees using a skin-surface device. Total lumbar and segmental flexion and extension ROM of L1-L2 to L5-S1 was compared between MSI sub-groups for each age group using separate two-way ANOVAs.

RESULTS

Significant main effects were found for the independent variables of MSI subgroup and age. Participants in all three age groups with a flexion-based MSI displayed significantly less lumbar extension (-0.6∘) at L4-5 as compared to participants with an extension-based MSI (-2.1∘), p= 0.03. In addition, lumbar total and segmental ROM was significantly less for older individuals in both subgroups.

CONCLUSIONS

Individuals with LBP may demonstrate a pattern of lumbar segmental hypomobility in the opposite direction of their MSI. Future studies may investigate the added value of direction-specific spinal mobilization to a program of MSI-based exercise.

Motor skill training versus strength and flexibility exercise in people with chronic low back pain: Preplanned analysis of effects on kinematics during a functional activity

BACKGROUND

People with chronic low back pain display the altered movement pattern where the lumbar spine moves more readily into its available range of motion relative to other joints. A logical approach to treatment, therefore, would be to improve this pattern during functional activities.

METHODS

154 participants were randomized to receive 6 weeks of motor skill training or strength and flexibility exercise. Participants in the motor skill training group received person-specific training to modify their altered movement pattern during functional activities. Participants in the strength and flexibility group received exercises for trunk strength and trunk and lower-limb flexibility. At baseline, post-treatment and 6-months after treatment participants performed a test of picking up an object using their preferred pattern. Three-dimensional marker co-ordinate data were collected. A mixed-model repeated measures analysis of variance was used to examine the treatment group and time effects.

FINDINGS

Motor skill training: Baseline early excursion values [mean (confidence interval)] were as follows: knee = 11.1°(8.0,4.1), hip = 21.2°(19.2,23.1), lumbar = 11.3°(10.4,12.3). From baseline to post-treatment significant improvements in early excursion included: knee = +18.6°(15.4,21.8), hip = +10.8°(8.8,12.8), and lumbar = -2.0°(-0.1,-4.0). There were no significant changes from post-treatment to 6-month follow-up. Strength and flexibility exercise: Baseline early excursion values were as follows: knee = 8.9°(5.8,11.9), hip = 20.8°(18.9,22.8), and lumbar = 11.2°(10.3,12.2) early excursion. There were no significant changes for knee, hip, and lumbar early excursion.

INTERPRETATION

Motor skill training was more effective than strength and flexibility exercise at changing and maintaining change to the altered movement pattern during a functional activity test of picking up an object.

Consistent differences in lumbar spine alignment between low back pain subgroups and genders during clinical and functional activity sitting tests

BACKGROUND

Subgroups of people with low back pain display differences in their lumbar alignment during tests from a clinical examination. However, it is unknown if subgroups display the same patterns during a functional activity test and if gender influences subgroup-related differences.

OBJECTIVES

Test if differences in lumbar alignment between two LBP subgroups are 1) present during a functional activity test of preferred sitting and 2) independent of gender.

DESIGN

Cross-sectional.

METHOD

154 participants with chronic low back pain were classified based on the Movement System Impairment Classification System by a physical therapist. Participants performed a functional activity test of preferred sitting and clinical tests of maximum flexed and extended sitting. 3D marker co-ordinate data were collected. Sagittal plane lumbar alignment, indexed by lumbar curvature angle, was calculated. A three-way mixed effect analysis of variance was used to examine effects of test, subgroup, gender, subgroup × test, gender × test and subgroup × gender.

RESULTS/FINDINGS

The lumbar rotation with extension subgroup [LCA = -8.0° (-9.5,-6.5)] displayed a more extended lumbar alignment than lumbar rotation [LCA = -5.9° (-7.4,-4.4)]. Women [LCA = -10.7° (-12.3,-9.2)] displayed a more extended lumbar alignment than men [LCA = -3.2° (-4.7,-1.7)]. There was a significant gender × test interaction (p = 0.01). The subgroup × test (p = 0.99) and subgroup × gender (p = 0.76) interactions were not significant.

CONCLUSIONS

LBP subgroup differences in lumbar alignment are present during preferred sitting. Gender-related differences in lumbar alignment are not driving subgroup differences. These findings highlight the need to use patient-specific clinical characteristics to guide treatment of a functional activity of preferred sitting limited due to low back pain.

Intersegmental kinematic analysis of lumbar spine by functional radiography between two subgroups of patients with chronic low back pain

INTRODUCTION

Kinematic deficits such as fault in joint accessory motion is one of the most important contributing factors for developing the movement impairment in the lumbar spine. Functional radiography is accessible method for detecting the artherokinematic disorders. The aim of this study was to compare lumbar spine intersegmental motion between low back pain (LBP) subgroups of movement system impairment (MSI) model by functional radiography.

MATERIALS AND METHODS

20 subjects with chronic LBP in two subgroups of the MSI model (Rotation with Flexion and Rotation with Extension) participated in this study. Five x-rays were taken in different positions. Intersegmental linear translation and angular rotation of the lumbar segments were calculated.

RESULTS

In the Rotation with Extension subgroup, the translation and rotation values of the L3-4 segment from full to full position were significantly more than their values in the Rotation with Flexion subgroup ((mean difference = -1.69 (mm) P = 0.01), (mean difference = -3.80 (mm) P = 0.02) respectively). The translation of L2-3 segment from the neutral to the mid-flexion position was significantly greater in the Rotation with Flexion subgroup compared to the Rotation with Extension subgroup (mean difference = 1.12 (mm) P = 0.04). cumulative intersegmental angular rotation of all lumbar segments from mid to mid position was greater in the Rotation with Flexion subgroup compared to the Rotation with Extension subgroup (P = 0.03).

CONCLUSION

Changes in intersegmental translation and angular rotation of lumbar segments in subgroups of patients with LBP may be important contributing factors that induce direction specific lumbar spine loads and contribute to the development or persistence of LBP problems.

Habitual posture and weekly time spent sitting do not contribute to the lumbopelvic curvature during active unilateral knee extension in sitting test

[Purpose] To investigate whether habitual pelvic posture and time spent sitting are primary contributing factors to performance in the active unilateral knee extension in sitting test in young people. [Participants and Methods] The participants’ ages ranged from 20 to 40 years. LUMOback, a wearable electronic device, was used to measure the proportion of the days spent in a neutral pelvic posture (posture score) and time spent sitting over a week. The lumbopelvic sagittal curvature from T12 to S2 (θ) during the active unilateral knee extension in sitting test was also assessed using a flexible ruler. A multiple regression analysis was performed with the primary independent variables of the posture score and time spent sitting, undertaking priori considerations of potential confounders of sex, and pain condition on the θ value. [Results] Eighty participants (21.7 ± 3.8 years) were enrolled in the study (24 males and 56 females). Neither the posture score nor time spent sitting statistically significantly contributed to the θ value. [Conclusion] Neither the proportion of the day spent with neutral pelvic posture nor time spent sitting detected by LUMOback was the primary contributing factor to the active unilateral knee extension in sitting test performance.

Effect of Chronic Low Back Pain on Lumbar Spine Lordosis During Sit-to-Stand and Stand-to-Sit

OBJECTIVE

This study aimed to evaluate lumbar lordosis during sit-to-stand (STS) and stand-to-sit (SIT) in individuals with and without chronic nonspecific low back pain (CNLBP). The second objective was to investigate sex-related differences in lumbar lordosis.

METHODS

Twenty-six patients with CNLBP and 26 controls were recruited. Controls were matched with cases using a frequency matching method. Reflective markers were placed over the spinous process of T₁₂, L₃, S₂, and the anterior and posterior superior iliac spines. The participants were instructed to stand up at a self-selected pace and maintain their normal upright standing posture for 3 seconds, and then sit down. Kinematic data were recorded at a sampling frequency of 100 Hz using a motion capture system. Lumbar lordosis angle was calculated from the intersection between the line joining T₁₂ and L₃, and the line joining L₃ to S₂.

RESULTS

Lumbar lordosis was decreased in patients with CNLBP during STS and SIT compared with the asymptomatic group (mean difference = 2.68°-9.32°; P ≤ .005). Furthermore, no differences were seen in lumbar lordosis at starting position between CNLBP and asymptomatic groups during STS and SIT (mean difference = 2.68°-3.75°; P ≥ .099). Interestingly, the magnitude of the effect size suggested that the difference in lumbar lordosis values between female and male participants was relatively large (Cohen's d = -1.81 to 0.20).

CONCLUSION

Decreased lumbar lordosis in patients with CNLBP during STS and SIT could be considered as an important point during rehabilitation. Moreover, the present study showed that there is a sex-related difference among women and men in lumbar lordosis during STS and SIT tasks.

Examination of the Lumbar Movement Pattern during a Clinical Test and a Functional Activity Test in People with and without Low Back Pain

BACKGROUND

It is assumed that the lumbar movement pattern observed during a clinical test is representative of the movement pattern used during a functional activity. Very little is known about how the lumbar movement pattern during a clinical test is associated with the lumbar movement pattern during a functional activity and how the lumbar movement pattern is associated with functional limitation.

OBJECTIVE

The purpose was to examine the lumbar movement pattern during a clinical test and a functional activity test in people with and people without low back pain (LBP), and the relationship of lumbar motion to LBP-related functional limitation.

DESIGN

Observational study.

PARTICIPANTS

16 back-healthy adults and 32 people with chronic LBP.

METHODS

Participants performed a standardized clinical test of forward bending and a functional activity test of picking up an object.

MAIN OUTCOME MEASUREMENTS

Maximal lumbar excursion and lumbar excursion at 0% to 50% and 50% to 100% of movement time were examined.

RESULTS

Significant associations were present between the two movement tests for both back-healthy people and people with LBP (r = 0.47-0.73). In people with LBP the amount of lumbar motion in the 0% to 50% of movement time interval for both tests was significantly associated with functional limitation (r = 0.43-0.62).

CONCLUSION

Lumbar movement patterns were similar between the two tests, and lumbar motion early in the movement of a functional test was related to self-report of functional limitation.

LEVEL OF EVIDENCE

III.

Can Biomechanics Research Lead to More Effective Treatment of Low Back Pain? A Point-Counterpoint Debate

SYNOPSIS

Although biomechanics plays a role in the development and perhaps the persistent or recurrent nature of low back pain (LBP), whether biomechanics alone can provide the basis for intervention is debated. Biomechanics, which refers to the mechanics of the body, including its neuromuscular control, has been studied extensively in LBP. But, can gains be made in understanding LBP by research focused on this component of biology in the multifactorial biopsychosocial problem of LBP? This commentary considers whether biomechanics research has the potential to advance treatment of LBP, and how likely it is that this research will lead to better treatment strategies. A point-counterpoint format is taken to present both sides of the argument. First, the challenges faced by an approach that considers biomechanics in isolation are presented. Next, we describe 3 models that place substantial emphasis on biomechanical factors. Finally, reactions to each point are presented as a foundation for further research and clinical practice to progress understanding of the place for biomechanics in guiding treatment of LBP. J Orthop Sports Phys Ther 2019;49(6):425-436. Epub 15 May 2019. doi:10.2519/jospt.2019.8825.

Motor Control Changes in Low Back Pain: Divergence in Presentations and Mechanisms

Compared to healthy individuals, patients with low back pain demonstrate differences in all aspects of trunk motor control that are most often studied as differences in muscle activity and kinematics. However, differences in these aspects of motor control are largely inconsistent. We propose that this may reflect the existence of 2 phenotypes or possibly the ends of a spectrum, with "tight control" over trunk movement at one end and "loose control" at the other. Both may have beneficial effects, with tight control protecting against large tissue strains from uncontrolled movement and loose control protecting against high muscle forces and resulting spinal compression. Both may also have long-term negative consequences. For example, whereas tight control may cause high compressive loading on the spine and sustained muscle activity, loose control may cause excessive tensile strains of tissues. Moreover, both phenotypes could be the result of either an adaptation process aimed at protecting the low back or direct interference of low back pain and related changes with trunk motor control. The existence of such phenotypes would suggest different motor control exercise interventions. Although some promising data supporting these phenotypes have been reported, it remains to be shown whether these phenotypes are valid, how treatment can be targeted to these phenotypes, and whether this targeting yields superior clinical outcomes. J Orthop Sports Phys Ther 2019;49(6):370-379. Epub 12 Jun 2018. doi:10.2519/jospt.2019.7917.

Comparison of Postural Balance between Subgroups of Nonspecific Low-back Pain Patients Based on O'Sullivan Classification System and Normal Subjects during Lifting

BACKGROUND

Balance disorder is one of the most-studied fields in low-back pain patients (LBP). However, there is insufficient information regarding the effect of LBP subgrouping on postural control. The purpose of the present study was to compare postural control between subgroups of chronic nonspecific LBP and healthy subjects during lifting.

METHODS

A total of 35 men with chronic LBP (19 active extension pattern [AEP] and 16 flexion pattern [FP]) and 15 healthy controls were enrolled in this cross-sectional study. Pooled LBP was subdivided based on the O'Sullivan's classification system (OCS). The participants were asked to lift a box from the ground to the waist level and hold it for 20 seconds. The load was 10% of the subject's weight. Force plate system was used to record balance parameters, including standard deviations (SDs) of center of pressure (COP) amplitude and COP velocity in anterior-posterior and medial-lateral directions and mean total velocity. The test was divided into two static and dynamic phases. Data were analyzed using one-way analysis of variance and independent t-test.

RESULTS

There were no significant differences between pooled LBP and control groups in any of the variables, except for the SD of the anterior-posterior direction velocity in the X-plane in the static phase (P=0.017). After classifying LBP, the results showed that the healthy and AEP groups were significantly different in SD of COP velocity in the frontal plane (P=0.021), mean total velocity (P=0.010), and SD of COP velocity in the sagittal plane (P=0.039).

CONCLUSION

The present study showed that postural control was not different between the pooled LBP and normal groups. After classifying pooled LBP based on OCS, we found that the AEP showed different postural control as compared to healthy controls in the dynamic phase. The FP and AEP exhibited different postural control relative to the healthy controls in the static phase, and COP velocity was lower in those groups compared to the control group. The results of this study support the concept of LBP classification.

The Ratio of Lumbar to Hip Motion during the Trunk Flexion in Patients with Mechanical Chronic Low Back Pain According to O'Sullivan Classification System: A Cross-sectional Study

BACKGROUND

Static and dynamic postures of lumbopelvic in low back pain (LBP) are considered as two important aspects of clinical assessment and management of LBP. Thus, the focus of the current study was to compare the posture and compensatory strategy of hip and lumbar region during trunk flexion between LBP subgroupsand health subjects. LBP cases are subdivided into active extension pattern (AEP) and flexion pattern (FP) based on O'Sullivan's classification system (OCS).

METHODS

This work was a cross-sectional study involving 72 men, 21 low back pain patients with FP and 31 low back pain patients with AEP and 20 healthy groups. Lumbar and hip angles during trunk flexion were measured by a 3D motion analysis system in neutral standing posture and end-range of trunk flexion. The participants were asked to full bend without any flexion of the knees. The bending speed was preferential. Hip and lumbar ranges of motion were divided into four quartiles (Q). The quartiles were compared between groups. Data analysis was performed using one-way analysis of variance (ANOVA) and independent t-test.

RESULTS

There was no statistically significant difference in lumbar lordosis in standing and full trunk flexion positions between the healthy groups and heterogeneous LBP groups. In addition, there was not any statistically significant difference between the healthy group and the homogenous LBP group (FP and AEP). Moreover, no statistically significant difference was observed in hip angles during standing between the healthy group and the heterogeneous LBP group, and between the healthy group and the homogenous LBP group (FP and AEP). In full trunk flexion position, there was statistically significant difference in hip angles between the healthy group and the heterogeneous LBP group (P=0.026). In this position, the difference in hip angles between the healthy group and FP group was statistically significant (P<0.05). In the second Q, there was no significant difference between the healthy group and the heterogeneous LBP group (P=0.062), however, there was a significant difference between FP group and the healthy group in the fourth Q of the total hip range of motion. There was no statistically significant difference between the healthy group and the heterogeneous LBP group (P=0.054) but there was a difference between FP group and the healthy group. Lumbar/hip motion ratio (L/H ratio) was different between and within the subgroups in the second Q.

CONCLUSION

This study supported the subgrouping of LBP and showed that the difference between subgroups could be determined effectively through subdividing the total range of lumbar and hip motions into smaller portions. It is possible that the neuromuscular system selects different strategies to compensate and prevent further injury of the chain components (muscle, joint, nerve and etc.).

LEVEL OF EVIDENCE

IV.

Test-retest reliability of sit-to-stand and stand-to-sit analysis in people with and without chronic non-specific low back pain

BACKGROUND

Sit-to-stand (STD) and stand-to-sit (SIT) analysis can provide information on functional independence in daily activities in patients with low back pain (LBP). However, in order for measurements to be clinically useful, data on psychometric properties should be available.

OBJECTIVES

The main purpose was to investigate intra-rater reliability of STD and SIT tasks in participants with and without chronic non-specific LBP (CNLBP). The second purpose was to detect any differences in lumbar spine and hips sagittal plane kinematics and coordination between asymptomatic individuals and CNLBP patients during STD and SIT.

DESIGN

Cross-sectional study.

METHOD

Twenty-three CNLBP patients and 23 demographically-matched controls were recruited. Ten markers were placed on specific anatomical landmarks. Participants were asked to perform STD and SIT at a preferred speed. Peak flexion angles, mean angular velocities, lumbar to hip movement ratios, and relative phase angles were measured. The procedure was repeated after 2 h and 6-8 days. Differences between two groups were analyzed using independent t-test. Intraclass correlation coefficient (ICC 3,k), standard error of measurement (SEM), and limits of agreement (LOAs) were also estimated.

RESULTS

The ICC values showed moderate to excellent intra-rater reliability, with relatively low SEM values (≤10.17°). The 95% LOAs demonstrated that there were no differences between the measured parameters. Furthermore, CNLBP patients had limited sagittal plane angles, smaller angular velocities, and lumbar-hip dis-coordination compared to asymptomatic participants.

CONCLUSIONS

The results indicated moderate to excellent test-retest reliability of STD and SIT analysis. Moreover, CNLBP patients had altered kinematics during STD and its reverse.

Diagnosis and treatment of movement system impairment syndromes

BACKGROUND

Diagnoses and treatments based on movement system impairment syndromes were developed to guide physical therapy treatment.

OBJECTIVES

This masterclass aims to describe the concepts on that are the basis of the syndromes and treatment and to provide the current research on movement system impairment syndromes.

RESULTS

The conceptual basis of the movement system impairment syndromes is that sustained alignment in a non-ideal position and repeated movements in a specific direction are thought to be associated with several musculoskeletal conditions. Classification into movement system impairment syndromes and treatment has been described for all body regions. The classification involves interpreting data from standardized tests of alignments and movements. Treatment is based on correcting the impaired alignment and movement patterns as well as correcting the tissue adaptations associated with the impaired alignment and movement patterns. The reliability and validity of movement system impairment syndromes have been partially tested. Although several case reports involving treatment using the movement system impairment syndromes concept have been published, efficacy of treatment based on movement system impairment syndromes has not been tested in randomized controlled trials, except in people with chronic low back pain.

The effect of an 8-week stabilization exercise program on the lumbopelvic rhythm and flexion-relaxation phenomenon

BACKGROUND

Lumbar stabilization exercise programs should normalize the aberrant movements patterns often observed in patients with low back pain. This study aimed to determine the effect of an 8-week lumbar stabilization program on EMG/kinematics measures of the aberrant movement patterns in such patients. A secondary goal was to assess the 8-week test-retest reliability of these measures.

METHODS

The patients followed an 8-week lumbar stabilization program while no intervention was carried out on the controls. Before and after this period, kinematics of the spine along with the EMG of paraspinal muscles were recorded during trunk maximal flexion-extension. ANOVAs tested the effect of the intervention in the patients, relative to the controls. Within the patients, correlation of the EMG/kinematics measures with the change in disability and pain following the intervention was investigated.

FINDINGS

A significant reduction in pain (Hedges's g effect size=2.31) and improvement in function (g=1.74) was reported in the patients. While EMG/kinematics measures disclosed impairments in the patients at baseline compared to the controls, no change was observed over the intervention. Nevertheless, the change of lumbar range of motion was positively correlated (r=0.42; P=0.015) with the change in disability.

INTERPRETATION

Although pain and disability decreased following the intervention, the EMG/kinematics measures did not change concomitantly suggesting that the patients learned to stiffen the lumbar spine during the treatment, and this technique was applied even if pain and disability unequivocally decreased after the treatment, which would not necessarily be beneficial to the patient.

Differences in lumbar spine and lower extremity kinematics in people with and without low back pain during a step-up task: a cross-sectional study

BACKGROUND

Low back pain (LBP) affects more than one third of the population at any given time, and chronic LBP is responsible for increased medical costs, functional limitations and decreased quality of life. A clear etiology is often difficult to identify, but aberrant posture and movement are considered contributing factors to chronic LBP that are addressed during physiotherapy intervention. Information about aberrant movement during functional activities in people with LBP can help inform more effective interventions. The purpose of this study was to determine if there are differences in lumbar spine and lower extremity kinematics in people with and without LBP during a step-up task.

METHODS

A convenience sample of 37 participants included 19 with LBP and 18 without a history of LBP. All participants were between the ages of 18 and 65, and controls were matched to participants with LBP based on age, gender and BMI. A motion capture system was used to record spine and lower extremity kinematics during the step-up task. ANOVA tests were used to determine differences in three-dimensional kinematics between groups.

RESULTS

Participants with LBP displayed less lower lumbar motion in the sagittal plane (P = 0.001), more knee motion in the coronal plane (P = 0.001), and more lower extremity motion in the axial plane (P = 0.002) than controls.

CONCLUSIONS

People with LBP display less lower lumbar spine motion in the sagittal plane and more out-of-plane lower extremity motion. Clinically, the step-up task can be used to identify these aberrant movements to develop more focused functional interventions for patients with LBP.

TRIAL REGISTRATION

Not applicable.

Consistency of a lumbar movement pattern across functional activities in people with low back pain

BACKGROUND

Limitation in function is a primary reason people with low back pain seek medical treatment. Specific lumbar movement patterns, repeated throughout the day, have been proposed to contribute to the development and course of low back pain. Varying the demands of a functional activity test may provide some insight into whether people display consistent lumbar movement patterns during functional activities. Our purpose was to examine the consistency of the lumbar movement pattern during variations of a functional activity test in people with low back pain and back-healthy people.

METHODS

16 back-healthy adults and 32 people with low back pain participated. Low back pain participants were classified based on the level of self-reported functional limitations. Participants performed 5 different conditions of a functional activity test. Lumbar excursion in the early phase of movement was examined. The association between functional limitations and early phase lumbar excursion for each test condition was examined.

FINDINGS

People with low back pain and high levels of functional limitation demonstrated a consistent pattern of greater early phase lumbar excursion across test conditions (p<0.05). For each test condition, the amount of early phase lumbar excursion was associated with functional limitation (r=0.28-0.62).

INTERPRETATION

Our research provides preliminary evidence that people with low back pain adopt consistent movement patterns during the performance of functional activities. Our findings indicate that the lumbar spine consistently moves more readily into its available range in people with low back pain and high levels of functional limitation. How the lumbar spine moves during a functional activity may contribute to functional limitations.

Difference between male and female workers lifting the same relative load when palletizing boxes

A few biomechanical studies have contrasted the work techniques of female and male workers during manual material handling (MMH). A recent study showed that female workers differed from males mostly in the strategy they used to lift 15-kg boxes from the ground, especially regarding task duration, knee and back postures and interjoint coordination. However, the lifting technique difference observed in females compared to males was perhaps due to a strength differences. The objective of this study was to test whether female workers would repeat the same lifting technique with a load adjusted to their overall strength (females: 10 kg; males: 15 kg), which can be considered a "relative load" since the overall back strength of females is 2/3 that of males. The task for the participants consisted in transferring boxes from one pallet to another. A dynamic 3D linked segment model was used to estimate the net moments at L5/S1, and different kinematic variables were considered. The results showed that the biomechanics of the lifting techniques used by males and females were similar in terms of task duration and cumulative loading, but different in terms of interjoint coordination pattern. The sequential interjoint coordination pattern previously seen in females with an absolute load (15 kg) was still present with the relative load, suggesting the influence of factors more intrinsically linked to sex. Considering that the female coordination pattern likely stretched posterior passive tissues when lifting boxes from the ground, potentially leading to higher risk of injury, the reason for this sex effect must be identified so that preventive interventions can be proposed.

Prolonged Intermittent Trunk Flexion Increases Trunk Muscles Reflex Gains and Trunk Stiffness

The goal of the present study was to determine the effects of prolonged, intermittent flexion on trunk neuromuscular control. Furthermore, the potential beneficial effects of passive upper body support during flexion were investigated. Twenty one healthy young volunteers participated during two separate visits in which they performed 1 hour of intermittent 60 seconds flexion and 30 seconds rest cycles. Flexion was set at 80% lumbar flexion and was performed with or without upper body support. Before and after intermittent flexion exposure, lumbar range of motion was measured using inertial measurement units and trunk stability was assessed during perturbations applied in the forward direction with a force controlled actuator. Closed-loop system identification was used to determine the trunk translational admittance and reflexes as frequency response functions. The admittance describes the actuator displacement as a function of contact force and to assess reflexes muscle activation was related to actuator displacement. Trunk admittance gain decreased after unsupported flexion, while reflex gain and lumbar range of motion increased after both conditions. Significant interaction effects confirmed a larger increase in lumbar range of motion and reflex gains at most frequencies analysed following unsupported flexion in comparison to supported flexion, probably compensating for decreased passive tissue stiffness. In contrast with some previous studies we found that prolonged intermittent flexion decreased trunk admittance, which implies an increase of the lumped intrinsic and reflexive stiffness. This would compensate for decreased stiffness at the cost of an increase in cumulative low back load. Taking into account the differences between conditions it would be preferable to offer upper body support during activities that require prolonged trunk flexion.

Sagittal Thoracic and Lumbar Spine Profiles in Upright Standing and Lying Prone Positions Among Healthy Subjects: Influence of Various Biometric Features

STUDY DESIGN

A prospective study was performed on the assessment of both thoracic and lumbar spine sagittal profiles (from C7 to S1).

OBJECTIVE

To propose a new noninvasive method for measuring the spine curvatures in standing and lying prone positions and to analyze their relationship with various biometric characteristics.

SUMMARY OF BACKGROUND DATA

Modifications of spine curvatures (i.e. lordosis or kyphosis) are of importance in the development of spinal disorders. Studies have emphasized the development of new devices to measure the spine sagittal profiles using a noninvasive and low-cost method. To date, it has not been applied for analyzing both lumbar and thoracic alterations for various positioning.

METHODS

Seventy-five healthy subjects (mean 22.6 ± 4.3 yr) were recruited to participate in this study. Thoracic and lumbar sagittal profiles were assessed in standing and lying prone positions using a 3D digitizer. In addition, several biometric data were collected including maximal trunk isometric strength for flexion and extension movement. Statistical analysis consisted in data comparisons of spine profiles and a multivariate analysis including biometric features, to classify individuals considering low within- and high between-variability.

RESULT

Kyphosis and lordosis angles decreased significantly from standing to lying prone position by an average of 13.4° and 16.6°, respectively. Multivariate analysis showed a sample clustering of 3 homogenous subgroups. The first group displayed larger lordosis and flexibility, and had low data values for height, weight, and strength. The second group had lower values than the overall trend of the whole sample, whereas the third group had larger score values for the torques, height, weight, waist, body mass index, and kyphosis angle but a reduced flexibility.

CONCLUSION

The present results demonstrate a significant effect of the positioning on both thoracic and lumbar spine sagittal profiles and highlight the use of cluster analysis to categorize subgroups after biometric characteristics including curvature measurement.

LEVEL OF EVIDENCE

N/A.

The effect of different lumbar belt designs on the lumbopelvic rhythm in healthy subjects

Background

Research suggests that in some patients with low back pain, lumbar belts (LB) may derive secondary prophylactic benefits. It remains to be determined, however, which patients are most likely to benefit from prophylactic LB use, and which LB design is optimal for this purpose. The objective of this study was to determine the effect of different lumbar belts designs on range of motion and lumbopelvic rhythm.

Methods

Healthy subjects (10 males; 10 females) performed five standing lumbar flexion/extension cycles, with knees straight, during a control (no belt) and four lumbar belt experimental conditions (extensible, with and without dorsal and ventral panels; non-extensible). Motion of the pelvis and lumbar spine was measured with 3D angular inertial sensors.

Results

The results suggest that adding dorsal and ventral panels to an extensible LB produces the largest lumbar spine restrictions among the four tested lumbar belt designs, which in turn also altered the lumbopelvic rhythm. On a more exploratory basis, some sex differences were seen and the sex × experimental condition interaction just failed to reach significance.

Conclusions

LB may provide some biomechanical benefit for patients with low back disorders, based on the protection that may be provided against soft tissue creep-based injury mechanisms. More comprehensive assessment of different LB designs, with additional psychological and neuromuscular measurement outcomes, however, must first be conducted in order to produce sound recommendations for LB use. Future research should also to take sex into account, with sufficient statistical power to clearly refute or confirm the observed trends.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2474-15-307) contains supplementary material, which is available to authorized users.

Altered muscle recruitment during extension from trunk flexion in low back pain developers

BACKGROUND

A functionally induced, transient low back pain model consisting of exposure to prolonged standing has been used to elucidate baseline neuromuscular differences between previously asymptomatic individuals classified as pain developers and non-pain developers based on their pain response during a standing exposure. Previous findings have included differences in frontal plane lumbopelvic control and altered movement strategies that are present prior to pain development. Control strategies during sagittal plane movement have not been previously investigated in this sample. The purpose of this research was to investigate neuromuscular control differences during the extension phase from trunk flexion between pain developers and non-pain developers.

METHODS

Continuous electromyography and kinematic data were collected during standing trunk flexion and extension on 43 participants (22 male) with an age range of 18-33 years, prior to entering into the prolonged standing exposure. Participants were classified as pain developer/non-pain developer by their pain response (≥ 10 mm increase on a 100 mm visual analog scale) during standing. Relative timing and sequencing data between muscle pairs were calculated through cross-correlation analyses, and evaluated by group and gender.

FINDINGS

Pain developers demonstrated a 'top-down' muscle recruitment strategy with lumbar extensors activated prior to gluteus maximus, while non-pain developers demonstrated a typical 'bottom-up' muscle recruitment strategy with gluteus maximus activated prior to lumbar extensors.

INTERPRETATION

Individuals predisposed to low back pain development during standing exhibited altered neuromuscular strategies prior to pain development. These findings may help to characterize biomechanical movement profiles that could be important for early identification of people at risk for low back pain.