Trunk Inclination Angle Research Articles

The Influence of Nordic Walking on Isokinetic Trunk Muscle Endurance and Sagittal Spinal Curvatures in Women after Breast Cancer Treatment: Age-Specific Indicators.

Nordic walking (NW) is a popular form of rehabilitation. NW improves psychophysical condition in breast cancer (BC) survivors. This study aimed to analyze the effects of NW on functional and postural changes of the trunk in women of different ages after BC. We hypothesized that an age relationship would be found. BC survivors (n = 39) were stratified by age as “middle- aged” (45–59 years) or “older” (60–75 years), then randomly allocated to the training intervention. A study group (SG, n = 19) participated in NW and a control group (CG, n = 20) performed general gymnastics. The sagittal spinal curvatures and isokinetic trunk muscle endurance were recorded at two time points, pre- and post-training intervention. Significant within NW group changes (p < 0.05) were found for the total work (TW) and average power (AP) of trunk flexors and extensors and the upper thoracic angle in middle-aged women. In older Nordic walkers, significant increases in TW and AP of the trunk flexor muscles were observed, with a negative increase in the trunk inclination angle. In CG, no significant functional or postural changes were observed in response to general gymnastics. NW improved both functional and postural changes in middle-aged women. This study identified the limitations of NW training in older women.

A sitting or standing position – which one exerts more loads on the musculoskeletal system of the lumbar spine? Comparative tests based on the methods of mathematical modelling

The work aimed to assess the functioning of the musculoskeletal system within the lumbar spine in relation to everyday postures of sitting and standing. The comparative analysis was based both on experimental tests and computer simulations performed in the AnyBody Modeling System environment. Input data used to prepare models were based on the information obtained in experimental tests. The test participants were tasked with adopting two postures: 1) standing position and 2) sitting position. Kinematics measurements were performed using the Zebris ultrasonic system. During sitting position, the tests additionally involved the use of a dynamometric platform measuring reaction forces occurring between buttocks and the seat. The comparative analysis included measurements of the trunk inclination angle and the pelvic inclination angle as well as results of computer simulations. The sitting posture is responsible for increased trunk inclination and a change in the position of the pelvis. In terms of the sitting position, it was possible to observe an increase in the loads affecting individual intervertebral joints of the lumbar spine by 155-184% in comparison with the standing posture (100%). Simulations revealed an increased muscle activity of the erector spinae, abdominal internal oblique muscles and abdominal external oblique muscles. Adopting a sitting position increases the loads on the lumbar spine and increases the activity of the erector spinae and abdominal muscles compared to the standing position, which is caused by change in the position of the pelvis and the curvature of the lumbar region.

Dynamic spinal posture and pelvic position analysis using a rasterstereographic device

BackgroundUntil recently, rasterstereographic analysis of the spine was limited to static measurements. However, understanding and evaluating the motion of the spine under dynamic conditions is an important factor in the diagnosis and treatment of spinal pathologies. The aim of this study was to study the spinal posture and pelvic position under dynamic conditions and compare it to static measurements using a dynamic rasterstereographic system.MethodsA total of 121 healthy volunteers (56 females; 65 males) were included in this observational study. The parameters trunk inclination, trunk imbalance, pelvic obliquity, kyphotic angle, lordotic angle, surface rotation, and lateral deviation were studied and compared under static and dynamic (1, 2, 4, 5 km/h) conditions using the system “Formetric 4D Motion®“ (DIERS International GmbH, Germany).ResultsFemale volunteers had a higher lordotic angle than males under static conditions (p < 0.001). Trunk inclination (5.31° vs. 6.74°), vertebral kyphotic angle (42.53° vs. 39, 59°), and surface rotation (3.35° vs. 3.81°) increase under dynamic conditions (p < 0.001). Trunk inclination and lordotic angle both show significant changes during walking compared to static conditions (p < 0.001).ConclusionThe spinal posture differs between females and males during standing and during walking. Rasterstereography is a valuable tool for the dynamic evaluation of spinal posture and pelvic position, which can also be used to quantify motion in the spine and therefore it has the potential to improve the understanding and treatment of spinal pathologies.Trial registrationRetrospectively registered

A flexible ergonomic redesign of the sewing machine workstation

Purpose The apparel industry is a labor-intensive industry, which depends mainly on the performance of the worker. The purpose of this study is to present an ergonomic redesign of the sewing machine workstation, with different sewing table heights and inclination angles, based on the operator’s anthropometric data. Design/methodology/approach A flexible ergonomic sewing table has been designed, four main workstation-setting factors were studied; sewing desk inclination angles – X_1, height – X_2, sewing machine type – X_3 and operator’s body mass index (BMI) – X_4, with three levels for each factor, except sewing machine type, which only has two levels. The study was undertaken to specify the limitations and advantages of each combination tested. Different measurement techniques were used; subjective information, production rates – P, working postures (head, neck and trunk inclination angles in the kinematic stage) were measured. Findings Sewing operators’ sitting posture angles in the kinematic stage were affected more or less by their anthropometric measurements and the type of sewing machine. These two factors should be taken into consideration when ergonomically redesigning the sewing machine workstation. Practical implications A new ergonomically redesigned sewing machine table can be incorporated into garment factories, taking into consideration the BMI of the operators to improve their productivity and reduce musculoskeletal disorder complaints due to incorrect operators’ posture. Originality/value An important correlation was found between the sewing operator’s anthropometric body measurement – BMI and the type of sewing machine (with significant R^2 = 0.8385 and 0.9764 with both the head and neck inclination angles O_H, O_N, respectively).

Evaluation of a new apparatus combining a mobile device and hand-held roller for the detection of spinal deformities: association with the sum of the right and left angles of trunk inclination.

To investigate the intra- and inter-observer reliabilities of the newly developed i-Scolioroller for scoliosis screening, and to determine the optimal i-Scolioroller measurement cutoff values for identifying adolescent scoliosis with a Cobb angle ≥ 20°. The i-Scolioroller displays the right- and left-side maximum inclination angle (Rmax, Lmax) during the forward bending test (FBT), as well as the angle of trunk inclination (ATI, i.e., whether the Rmax or Lmax is greater). Sum-ATI is defined as the sum of Rmax and Lmax. Intra-class correlation coefficients (ICC) of the ATI and sum-ATI measurements were calculated to analyze the intra- and inter-observer reliabilities for 10 plaster torsos in FBT positions obtained from patients with idiopathic scoliosis. The optimal cutoff values for scoliosis were determined using receiver operating characteristic (ROC) analysis of i-Scolioroller measurements versus Cobb angles obtained from the upright whole-spine radiographs of 112 adolescent outpatients. The intra-observer ICCs for the ATI/sum-ATI for 3 observers were 0.851/0.856, 0.786/0.900, and 0.772/0.796, respectively, while the corresponding inter-observer ICCs for all participants were 0.733/0.745. On ROC analysis, an ATI of 8° was the optimal cutoff value for scoliosis (sensitivity and specificity: 79.2% and 70.0%, respectively). The optimal cutoff value for sum-ATI was 11° (sensitivity and specificity: 86.1% and 82.5%, respectively). The areas under the ROC curves were 0.859 for ATI and 0.908 for sum-ATI. The optimal cutoff values for identifying scoliosis using the i-Scolioroller were a combination of 11° for the sum-ATI and 8° for the ATI.

Biomechanical load during patient transfer with assistive devices: Cross-sectional study

This study utilised a cross-sectional design to perform measurements of muscle activity as well as forward - and lateral trunk inclination angle during a full workday among 52 female healthcare workers from 16 different departments at five Danish hospitals. Using linear mixed models, the 95th percentile ranks of the normalised root mean square (nRMS) values were analysed for the different types of assistive devices. Compared to no assistive device (mean nRMS 27.9%, 95% CI 24.8%–31.0%), the use of intelligent beds (23.9%, CI 20.2%–27.6%) and ceiling-lifts (24.0%, CI 20.3%–27.7%) led to lower erector spinae nRMS values across all types of patient transfers. Conversely, the use of bedsheets (30.6%, CI 27.1%–34.2%), sliding-sheets (30.3%, CI 26.8%–33.9%) and sliding-boards (33.5%, CI 29.5%–37.6%) were associated with higher levels of erector spinae muscle activity.Consistent use of ceiling-lifts and intelligent beds reduces the physical workload and may thereby decrease the risk of musculoskeletal disorders among healthcare workers. Practioner Summary: Frequent patient transfer is associated with an increased risk of back pain and injury among healthcare workers. This analysis compares the level of physical load during patient transfer with commonly used assistive devices. The results show that use of the ceiling-lift and intelligent bed is associated with relatively low physical load during patient transfer. Abbreviations: RMS: root mean square; nRMS: normalized root mean square; EMG: electromyography; MSD: musculoskeletal disorder; LBP: low-back pain; VAS: visual analogue scale; MVC: maximal voluntary contraction

Effect of changing water depth on muscle activity and motion kinematics during sit-to-stand motion

BackgroundSit-to-stand (STS) movement is a fundamental activity in daily life. Studies have examined the effect of water depth during aquatic exercise; however, no investigation has examined the effect of water depth on STS movements. Research questionThis study examined whether changing water depth affected muscle activity and motion kinematics during the STS movement. MethodsEleven participants performed the STS movement on the ground (land) and at different water depths (1.0-m [deep] and 0.6-m [shallow]) at a self-determined pace. Lower extremity and trunk muscle activity, lower extremity joint angle, and trunk segment inclination angle were measured. Mean muscle activity during STS movement, initial and final postures, and range of motion of each angle was evaluated. Correlations of a normalised time-series pattern of electromyography and motion kinematics measures between land and shallow (land-shallow) and between land and deep (land-deep) were investigated. ResultsThe rectus femoris was more active in shallow than in deep water STS movement but less than that in land STS. Other muscles showed no significant differences between shallow and land STS movement. Correlation of the time series pattern in the tibialis anterior, rectus femoris, and erector spinae muscles was higher in the land-shallow than the land-deep STS. The trunk showed more forward inclination in the shallow STS than the land but less than the deep. Correlation of the time series pattern in the hip joint and trunk inclination angles was higher in the land-shallow STS than in the land-deep STS. SignificanceSTS exercise in the shallow water depth reduced muscle load for the knee extensor but not for other muscles. The muscle activity pattern showed a higher correlation between the land STS and shallow water than deep. Sitting posture becomes upright when the water depth decreases, but a similar motion pattern could be attained regardless of water depth.

The Effect of Abdominal and Spinal Muscles Fatigue in Spinal Postures

Background: A Pre/Post-Test Cohort investigating the effect of spinal and abdominal muscles fatigue on spinal curvatures. Method and Results: The effect of spinal and abdominal muscle fatigue on pelvic tilt, trunk inclination and the lordotic angle, and on the rotation of the T6, L2 and L4 vertebras was investigated in 10 healthy individuals. Abdominal and spinal muscles fatigue had a significant effect (p &lt;0.05) on pelvic tilt, trunk inclination and lordotic angle. Conclusion: Application of simple and quick fatigue tests resulted in changes in all static parameters (pelvic tilt, trunk inclination and lordotic angle) as measured by the DIERS system.

Entrenamiento de la flexibilidad en voleibol sentado

La presente investigación es un estudio cuasi experimental que muestra los efectos de un programa de entrenamiento de la flexibilidad de la cadena muscular posterior sobre el alcance funcional y la ejecución del golpe de antebrazos en un grupo de jugadores de voleibol sentado de la liga de Bogotá. Dicho programa se fundamentó en la combinación de dos técnicas de desarrollo de la flexibilidad, facilitación neuromuscular propioceptiva (FNP) y estiramiento dinámico. Se llevó a cabo durante seis semanas, para un total de 17 sesiones, cada una de 30 minutos de duración y dos sesiones para aplicar el pre test y post test. El estudio muestra significación estadística en los resultados de los test de flexibilidad, sin embargo, no se obtiene significación en los resultados del test de alcance funcional ni en la evaluación del golpe de antebrazos, aunque si se observan cambios a nivel clínico. Además de esto se encuentra una correlación de significación estadística entre el test de sit and reach y el ángulo de inclinación del tronco, medido a través de análisis de gesto por medio del software kinovea.

Using the Scoliometer and a Surface Topography Apparatus to Check if Back Trunk Asymmetry Changes in Children and Adolescents in the Forward Flexion and Standing Erect Positions.

BackgroundThe purpose of this study is to evaluate the effects of the forward bending (FB) test versus the standing erect (SE) position on back trunk asymmetry (TA). The Scoliometer in the FB position and the 4D Formetric (4DF; Diers International, Schlangenbad, Germany) readings in the SE position were assessed.MethodThe angle of trunk inclination (ATI) was measured at the midthoracic, thoracolumbar, and lumbar levels using the Scoliometer in the FB position and the 4DF in the SE position.A total of 134 subjects attending the scoliosis clinic (86 girls and 48 boys), age ranging from seven to 18 years, were assessed. The children and adolescents were divided into three groups according to the severity of TA, symmetric group 1 (0-2 degrees), asymmetry group 2 (2 to 6 degrees), and group 3 having asymmetry of seven or more degrees. Children with leg length discrepancy were excluded from the study.The IBM SPSS v.20 package (IBM Corp., Armonk, NY) was used for analysis.ResultsAt the midthoracic level comparing the Scoliometer to 4DF readings in males in group 1, the Wilcoxon signed ranks test was p=0.451 while for the Spearman’s Rho, it was -0.138; in group 2, p=0.184 and Rho=0.204; and in group 3, p=0.109 and Rho=0.500. For females in group 1, p=0.000 while Rho=0.003; in group 2, p=0.008 and Rho=0.000, and in group 3, p=0.003 while Rho=0.642.At the thoracolumbar level in males for group 1, p=0.004 and Rho=-0.517; in group 2, p=0.006 and Rho=0.000; and in group 3, p=0.043 while Spearman’s Rho=0.053. For females in group 1, p=0.000 and Rho=-0.095; in group 2, p=0.000 and Rho=-0.171; in group 3, p=0.001 while Rho= -0.081. At the lumbar level for males in group 1 p=0.000 while Rho=0.149; in group 2, p=0.003 and Rho=0.373; while in group 3, p=0.109 and Rho= (-). For females in group 1, p=0.000 while Rho=-0.072; in group 2, p=0.001 and Rho=0.168; and in group 3, p=0.068 while Rho=0.500.ConclusionThe results of this study show that the back TA in children and adolescents is not similar in the FB and SE positions. This phenomenon probably is attributed to the complicated trunkal (spinal, thoracic, and pelvic) anatomy, and the results of this study may be used as a useful foundation for further understanding of torso dynamics.

Real-time feedback to reduce low-back load in lifting and lowering

Low-back pain (LBP) is a common health problem. Literature indicates an exposure-response relation between work-related lifting and LBP. Therefore, this study investigated effects of three kinds of real-time feedback on low-back load, quantified as lumbar moments, during lifting. We recruited 97 healthy male and female participants without a recent history of LBP and without prior biomechanical knowledge on lifting. Participants were assigned to groups based on the time of enrollment, filling the four groups in the following order: moment feedback, trunk inclination angle feedback, lumbar flexion feedback, and a control group not receiving feedback. Feedback was given by a sound when a threshold level of the input variable was exceeded. Participants were unaware of the input variable for the feedback, but were instructed to try to avoid the audio feedback by changing their lifting strategy. The groups with feedback were able to reduce the audio feedback and thus changed the input variable towards a more desired level. Lumbar moments significantly decreased over trials in the inclination and moment feedback groups, remained similar in the lumbar flexion group and increased in the control group. Between group comparisons revealed that low-back load was significantly lower in the moment and inclination groups compared to the control group. Additionally, moments were lower in the inclination group than in the lumbar flexion group. Real-time feedback on moments or trunk inclination is a promising tool to reduce low-back load during lifting and lowering.

Decreased Vertical Trunk Inclination Angle and Pelvic Inclination as the Result of Mid-High-Heeled Footwear on Static Posture Parameters in Asymptomatic Young Adult Women.

The influence of high-heel footwear on the lumbar lordosis angle, anterior pelvic tilt, and sacral tilt are inconsistently described in the literature. This study aimed to investigate the impact of medium-height heeled footwear on the static posture parameters of homogeneous young adult standing women. Heel geometry, data acquisition process, as well as data analysis and parameter extraction stage, were controlled. Seventy-six healthy young adult women with experience in wearing high-heeled shoes were enrolled. Data of fifty-three subjects were used for analysis due to exclusion criteria (scoliotic posture or missing measurement data). A custom structured light surface topography measurement system was used for posture parameters assessment. Three barefoot measurements were taken as a reference and tested for the reliability of the posture parameters. Two 30-degree wedges were used to imitate high-heel shoes to achieve a repeatable foot position. Our study confirmed the significant (p < 0.001) reduced vertical balance angle and pelvis inclination angle with large and medium-to-large effects, respectively, due to high-heel shoes. No significant differences were found in the kyphosis or lordosis angles. High-heeled shoes of medium height in young asymptomatic women can lead to a straightening effect associated with a reduced vertical balance angle and decreased pelvic inclination.

Effects Of Running Biomechanics On The Occurrence Of Iliotibial Band Syndrome- A Prospective Study

Iliotibial band syndrome (ITBS) is the second most common running injury, accounts for 1.6%-12% of all running-related injuries. The exact etiology of ITBS is unclear, but gait and posture are considered one of the factors. Most of studies on ITBS were retrospective cross-sectional in design and could not elaborate on the pathogenesis of ITBS. PURPOSE: This prospective study aimed to determine the gait characteristics that easily induce ITBS and explore the posture changes after the occurrence of ITBS. METHODS: 15 ITBS-stricken runners (I group) and matched 15 healthy runners (C group). All participants underwent two gait trials, namely, before the first day of running (trial1) and after 8-week running (trial2). An eight-camera motion capture system was used to collect kinematic data. Sub-group comparisons were assessed via respective 95% confidence intervals of mean difference. RESULTS: In trial2, the ITBS group exhibited greater peak anterior pelvic tilt and hip flexion angle than the control group(Fig1a). The ITBS group showed increased peak trunk inclination angle , whereas the control group demonstrated lower peak hip flexion (Fig1b)and peak hip adduction than those at trial1(Fig1c).Fig 1: Comparison of joint activity between the two groups■■ Represent significant differences between the two groups in trial 2. ▲▲ Significant differences in the control group compared with trial 1. Abbreviation: t1: trial1; t2: trial2 ; LTD=left foot touch down; LTO=left foot take off; RTD=right foot touch down; RTO= right foot take off; CONCLUSION: Decreasing the peak hip flexion and peak hip adduction angle may be a reasonable strategy to avoid the occurrence of ITBS. Occurrence of ITBS may be due to the lack of timely gait adjustment. The posture of excessive trunk inclination and anterior pelvic tilt may be a risk factor in the development of ITBS during running. This work was supported by the Project of Shandong Science & Technology Department (2017G006044).

Trunk inclination and hip extension mobility, but not thoracic kyphosis angle, are related to 3D-accelerometry based gait alterations and increased fall-risk in older persons

BackgroundOnly a portion of the increased variability in gait parameters observed in ageing can be explained by age and gait speed alone. Other factors, like musculoskeletal changes of the spine, might contribute to higher variability of gait parameters, slower walking speed and subsequently increased fall-risk in ageing. Research questionAre spinal posture and mobility related to 3D-accelerometry based gait analysis, functional performance and fall-risk in ageing? MethodsForty elderly presenting increased fall-risk (OFR, 80.6 ± 5.4yrs), 41 old controls (OC, 79.1 ± 4.9yrs), and 40 young controls (YC, 21.6 ± 1.4yrs) were assessed for spinal posture and mobility (SpinalMouse®), gait analysis (DynaPort MiniMod), and functional performance (grip strength, grip work, timed-get-up-and-go-test, performance-oriented mobility assessment). ResultsCompared to OC, OFR showed significantly (p < .05) larger trunk inclination angle (INC), smaller sacral extension mobility, slower walking speed, and lower medio-lateral step and stride regularity. Thoracic kyphosis angle (TKA) was similar in all groups. INC and sacral extension mobility showed the highest correlation with walking speed, gait parameters, functional performance and fall-risk. INC (OR = 1.14) and sacral extension mobility (OR = 1.12) can moderately explain fall-risk in elderly participants and showed fair capacity to discriminate OFR from OC, the diagnostic value on fall-risk is however low (best probabilistic cut-off value, INC: -0.83° [sensitivity = 70%, specificity = 61%, PPV = 64%, NPV = 68%, LR+ = 1.79, LR- = 0.49, AUC = 0.71]; sacral extension mobility: 8.5° [sensitivity = 70%, specificity = 73%, PPV = 72%, NPV = 71%, LR+ = 2.61, LR -= 0.41, AUC = 0.71]). SignificanceLarger trunk inclination and smaller sacral extension mobility (i.e. hip extension mobility) are moderately related to increased fall-risk, gait alterations, lower muscle performance and worse functional mobility in ageing. Contrary to our hypothesis, TKA showed no relation with parameters of gait and/or fall-risk. INC and sacral extension mobility have fair discriminative power to distinguish older persons with increased fall-risk from those without and might be considered as therapeutic targets.

Rubber Tree Crown Segmentation and Property Retrieval Using Ground-Based Mobile LiDAR after Natural Disturbances

Rubber trees in southern China are often impacted by natural disturbances, and accurate rubber tree crown segmentation and property retrieval are of great significance for forest cultivation treatments and silvicultural risk management. Here, three plots of different rubber tree clones, PR107, CATAS 7-20-59 and CATAS 8-7-9, that were recently impacted by hurricanes and chilling injury were taken as the study targets. Through data collection using ground-based mobile light detection and ranging (LiDAR) technology, a weighted Rayleigh entropy method based on the scanned branch data obtained from the region growing algorithm was proposed to calculate the trunk inclination angle and crown centre of each tree. A watershed algorithm based on the extracted crown centres was then adopted for tree crown segmentation, and a variety of tree properties were successfully extracted to evaluate the susceptibility of different rubber tree clones facing natural disturbances. The results show that the angles between the first-order branches and trunk ranged from 35.1–67.7° for rubber tree clone PR107, which is larger than the angles for clone CATAS 7-20-59, which ranged from 20.2–43.2°. Clone PR107 had the maximum number of scanned leaf points, lowest tree height and a crown volume that was larger than that of CATAS 7-20-59, which generates more frontal leaf area to oppose wind flow and reduces the gaps among tree crowns, inducing strong wind loading on the tree body. These factors result in more severe hurricane damage, resulting in trunk inclination angles that are larger for PR107 than CATAS 7-20-59. In addition, the rubber tree clone CATAS 8-7-9 had the minimal number of scanned leaf points and the smallest tree crown volume, reflecting its vulnerability to both hurricanes and chilling injury. The results are verified by field measurements. The work quantitatively assesses the susceptibility of different rubber tree clones under the impacts of natural disturbances using ground-based mobile LiDAR.

Effects of running biomechanics on the occurrence of iliotibial band syndrome in male runners during an eight-week running programme—a prospective study

ABSTRACT Iliotibial band syndrome (ITBS) is a common injury that is related to running biomechanics. This study aimed to determine the gait characteristics that easily induce ITBS and explore the gait changes after the occurrence of ITBS. Thirty healthy male recreational runners participated in our study. Amongst them, 15 developed ITBS and comprised the ITBS group; the other 15 were healthy and comprised the control group. All participants underwent two gait trials, namely, before the first day of their running and after eight weeks, during which a force platform and a motion capture system collected biomechanical data. After running, the ITBS group exhibited greater anterior pelvic tilt and hip flexion angle than the control group. The ITBS group showed increased trunk inclination angle, whereas the control group demonstrated lower hip flexion, hip adduction angle and hip abductor moment than those at the beginning of running. Decreasing hip flexion, adduction angle and abductor moment may be a reasonable strategy to avoid the occurrence of ITBS. The occurrence of ITBS may be due to the lack of timely gait adjustment. Excessive trunk inclination and anterior pelvic tilt angle may be risks factor in the development of ITBS during running.

Effects of lung volume on the depth of center of gravity, trunk inclination angle, and projected frontal area during front crawl swimming

Effects of lung volume on the depth of center of gravity, trunk inclination angle, and projected frontal area during front crawl swimming

Comparison of the Spinal Loads Produced by Carrying a Backpack and Carrying a Person Piggyback: Crossfit Training

Background of Study: The piggyback carry has recently become a more popular exercise through the emerging sport of CrossFit. Purpose: The purpose of this study was to determine any biomechanical differences that exist in the lumbar spine when carrying no load, a backpack, and a person on the back. Methods: Twelve 70+ kg male strength-trained athletes were recruited from local CrossFit affiliates. One child with a mass of 27 kg was recruited to be the piggybackpassenger for all participants. All participants and the guardian of the passenger signed an informed consent form. The participants walked three times over a force plate for each of three conditions: carrying no load, a 27 kg backpack, or a 27 kg passenger. Three Canon video cameras recorded each trial, and Dartfish Software was used to measure joint angles and gait parameters. Maximal trunk inclination angle, was used in a static lumbar spine model to calculate trunkmuscle torque and force, and lumbosacral joint reaction forces. Results: Both load conditions produced compensatory trunk flexion; trunk flexion increased from no load to piggybacking to backpacking. Mean values were determined for each participant for each variable, and these values were compared amongst the three conditions of no load, piggybacking, and backpacking. An alpha value of 0.05 was used. Conclusion: Due to the more extreme position of the trunk andgreater magnitude of torques, backpacking likely places the musculoskeletal system at more risk than does piggybacking.

Long-term Tai Chi practitioners have superior body stability under dual task condition during stair ascent

BackgroundStair walking contributed to 26% of self-reported falls and become the leading cause of accidental death for the elderly. The risk of fall increases while performing a cognitive task, like talking and/or reasoning. Research questionOur work aimed to found out whether body stability under physical-cognitive dual task(DT) condition during stair ascent is superior among long-term Tai Chi (TC) practitioners. MethodsFifteen healthy, elderly long-term TC practitioners and fifteen no exercise(NE) practitioners were asked to walking ascent the stairs under single task(ST) and DT conditions in this cross-sectional study. Vicon motion analysis system and Kistler force plates were used synchronously to collect data. Ninety-five% confidence intervals, effect size and statistical power were calculated for each dependent variable to confirm significant difference. ResultsCompared with NE practitioners, TC practitioners had a lower head inclination angle, trunk inclination angle, hip angle, laterial impulse and center of mass-center of pressure(COM-COP)ap/ml separation, a higher ankle angle and loading rate under DT condition; TC practitioners had a lower head inclination angle, trunk inclination angle, higher ankle angle, loading rate and COM-COPml separation under ST condition. Compared with under ST condition, TC practitioners increased in minimum foot clearance, NE practitioners increased in laterial impulse and COM-COPml separation under DT condition. Under DT condition, body stability decreased among NE practitioners, while TC practitioners remained unchanged. SignificanceAt present, there is no drug therapy proven to delay preclinical cognitive deterioration, it would be great helpful for the elderly if TC was been proved to improve their performance under cognitive related conditions.

Spinal posture changes using dynamic rasterstereography during the modified Matthiass test discriminate between postural weak and strong healthy children (10-14years): a pilot study.

The aim of this pilot study was to investigate whether the clinical Matthiass test can be objectified by means of dynamic rasterstereography in children. We aimed at discriminating between postural weak and strong children. Dynamic rasterstereography was used to capture sagittal spinal posture changes during the modified Matthiass test (mMT). Primary outcomes were spinal posture changes (trunk inclination, kyphotic and lordotic angles) during the test. Two-step cluster analysis was run jointly on the three primary outcomes. Data of 101 healthy children (10-14years, 46% girls) were assessed. Cluster analysis identified two groups of participants with significantly different postural performance levels during the mMT (low vs. high performers). Low performers showed a higher increase in backward lean, as well as kyphosis and lordosis (4°-5°, respectively) when compared to high performers. The two performance groups were age-, BMI-, and activity-matched.Conclusion: This pilot study established preliminary normative data on spinal posture changes during the Matthiass test (high performers) and provided corresponding cutoff values for postural weakness (low performers). These results could provide a basis for future longitudinal and interventional studies targeting long-term consequences of childhood postural weakness and the prevention of back pain. What is Known: • The prevalence of postural insufficiencies in children is high. • No consensus exists about the postural assessment in children. • A common clinical test to identify postural insufficiency is the Matthiass test yet criticized for its subjective assessment. What is New: • This pilot study objectified the modified Matthiass test by rasterstereography and statistically identified two groups of healthy children with different postural performance levels. • It established preliminary normative data on spinal posture changes and provided corresponding cutoff values for postural weakness.