Trunk Inclination Research Articles

Wearable Sensors System for an Improved Analysis of Freezing of Gait in Parkinson's Disease Using Electromyography and Inertial Signals.

We propose a wearable sensor system for automatic, continuous and ubiquitous analysis of Freezing of Gait (FOG), in patients affected by Parkinson’s disease. FOG is an unpredictable gait disorder with different clinical manifestations, as the trembling and the shuffling-like phenotypes, whose underlying pathophysiology is not fully understood yet. Typical trembling-like subtype features are lack of postural adaptation and abrupt trunk inclination, which in general can increase the fall probability. The targets of this work are detecting the FOG episodes, distinguishing the phenotype and analyzing the muscle activity during and outside FOG, toward a deeper insight in the disorder pathophysiology and the assessment of the fall risk associated to the FOG subtype. To this aim, gyroscopes and surface electromyography integrated in wearable devices sense simultaneously movements and action potentials of antagonist leg muscles. Dedicated algorithms allow the timely detection of the FOG episode and, for the first time, the automatic distinction of the FOG phenotypes, which can enable associating a fall risk to the subtype. Thanks to the possibility of detecting muscles contractions and stretching exactly during FOG, a deeper insight into the pathophysiological underpinnings of the different phenotypes can be achieved, which is an innovative approach with respect to the state of art.

Evaluation of Inertial Sensor-Based Pre-Impact Fall Detection Algorithms Using Public Dataset.

In this study, pre-impact fall detection algorithms were developed based on data gathered by a custom-made inertial measurement unit (IMU). Four types of simulated falls were performed by 40 healthy subjects (age: 23.4 ± 4.4 years). The IMU recorded acceleration and angular velocity during all activities. Acceleration, angular velocity, and trunk inclination thresholds were set to 0.9 g, 47.3°/s, and 24.7°, respectively, for a pre-impact fall detection algorithm using vertical angles (VA algorithm); and 0.9 g, 47.3°/s, and 0.19, respectively, for an algorithm using the triangle feature (TF algorithm). The algorithms were validated by the results of a blind test using four types of simulated falls and six types of activities of daily living (ADL). VA and TF algorithms resulted in lead times of 401 ± 46.9 ms and 427 ± 45.9 ms, respectively. Both algorithms were able to detect falls with 100% accuracy. The performance of the algorithms was evaluated using a public dataset. Both algorithms detected every fall in the SisFall dataset with 100% sensitivity). The VA algorithm had a specificity of 78.3%, and TF algorithm had a specificity of 83.9%. The algorithms had higher specificity when interpreting data from elderly subjects. This study showed that algorithms using angles could more accurately detect falls. Public datasets are needed to improve the accuracy of the algorithms.

Spino-pelvic- lower extremity balance during walking in elderly patients with spinal kyphosis

Back groundPatients with spinal kyphosis were radiographically evaluated while standing. However, the spino-pelvic alignment during walking is different. This study examined the spino-pelvic-lower extremity alignment during walking by a three-dimensional (3D) motion analysis. MethodsTwenty-six patients with a sagittal vertical axis of ≥4 cm (male: female, 5:21; average age, 66 years) were evaluated. Using a 3D motion capture system, the trunk and pelvic anterior inclination angles, hip and knee joint angles were measured during a 3-min walk. The correlation coefficient between the change of the trunk anterior inclination angle and each parameter at the beginning of walking was calculated, and those parameters were compared with radiographic measurements. ResultsThe patients were divided into two groups according to the change of the trunk anterior inclination angle: the large change group included 14 patients with an increase of ≥5° between the beginning and end of the 3-min walk; the small change group included 12 patients with an increase of <5°. The pelvic anterior inclination angle showed a significant difference between the two groups at the first gait cycles. The pelvic anterior inclination angle and the hip joint angle in the large change group showed a significant difference between the first and last cycles. The correlation coefficient revealed a significant association between the change in the trunk anterior inclination angle and the pelvic anterior inclination angle at the beginning of walking. There were no significant differences between the two groups in any radiographic spino-pelvic parameters. ConclusionsThere were two types of patients with spinal kyphosis: patients with a small pelvic anterior inclination angle at the beginning of walking showed slight progression in their trunk anterior inclination, whereas those with a large pelvic angle showed a large degree of progression in their pelvic and trunk inclination during walking.

Parameters for gait rehabilitation in Tropical Spastic Paraparesis: cross sectional study

INTRODUCTION: The gait in people with HTLV-1 associated myelopathy or tropical spastic paraparesis (HAM / TSP) is little known. OBJECTIVE: To evaluate the kinematic profile of gait in people with HAM/TSP. METHODS: A cross-sectional study with 25 people with HAM/TSP and 25 healthy participants. Spatiotemporal and angular data from filming of gait were submitted to kinematic analysis using CVMob software. The gait of partipants with HAM/TSP was analized quantitatively through t Student test (alpha 5% and Power of 80%). The project was approved by Ethical Committee of the Bahiana School of Medicine and Public Health with CAAE 13568213.8.0000.5544. RESULTS: The HAM/TSP group showed significant changes in two different domains of biomechanical gait analysis when compared to healthy controls. The angular variables showed increased trunk inclination, flexion and extension (p&lt;0.05); increased hip flexion and decreased hip extension (p&lt;0.05); decreased knee flexion and extension (p&lt;0.05); decreased ankle dorsi and plantar flexion (p&lt;0.05). Range of Motion was also reduced in all those joints. The spatiotemporal variables showed decreased stride length and increased stride time and speed gait cycle (p&lt;0.001). Those changes point out to reduction in joint amplitudes of hip, knee and ankle, changes in support base and double support time asymmetry between right and left sides, reduction of pre-swing time, hip lift in the mid-swing, and foot drop throughout the swing. CONCLUSION: People with HAM/TSP have gait characterized by reduction in joint amplitudes of hip, knee and ankle, asymmetry between right and left sides and reduction of pre-swing time, hip lift in the mid-swing, and foot drop throughout the swing.

Efficacy of the use of the McKenzie and Vojta methods to treat discopathy-associated syndromes in the pediatric population.

This paper evaluates the efficacy of using the McKenzie and Vojta methods for patients with low back pain and the use of the DIERS Formetric 4D system as an objective diagnostic tool. The study enrolled 28 patients aged 15-17 years old. The patients were hospitalized at the Department of Orthopedics and Traumatology of the Świętokrzyskie Center for Pediatrics in Kielce with a diagnosis of back pain associated with a discopathy. The patients were rehabilitated according to the McKenzie and Vojta methods. Assessment by means of the DIERS Formetric system had taken place before the first therapy session and on the day that pain was eliminated to evaluate trunk inclination, angle of thoracic kyphosis, angle of lumbar lordosis, lateral deviation, trunk torsion, surface rotation and pelvic obliquity. Pain intensity and change in pain intensity over time were assessed by means of a numerical rating scale. Pain intensity was reduced to 0 over 3-12 days. The study participants demonstrated reduction in anterior trunk inclination of the mean value at 1.83°. The angle of thoracic kyphosis was also reduced by 7.95°. The angle of lordosis increased by 7.6°. The lateral spinal curvature was reduced by 8.92 mm. There was a reduction of 4.64° in trunk torsion. Surface rotation was reduced by 1.61° and pelvic obliquity was reduced by 3.78°. In discopathic patients, postural parameters comprising trunk inclination, angle of thoracic kyphosis, angle of lumbar lordosis, lateral deviation, trunk torsion, vertebral rotation and pelvic obliquity fail to reach Hartzmann's physiological reference ranges. A therapeutic intervention based on the Vojta and McKenzie methods may normalize the posture to physiological reference ranges and is effective in the treatment of patients with back pain. The DIERS system is an objective tool for tracing the effects of therapy in patients with back pain. Int J Occup Med Environ Health. 2019;32(1):33-41.

Sustained maximal inspiration has similar effects compared to incentive spirometers

PurposeTo compare the effects of flow incentive spirometer (FIS), volume incentive spirometer (VIS), and sustained maximal inspiration exercise (SMI) on breathing pattern, chest wall motion, and thoracoabdominal asynchrony. MethodsSixteen healthy adults aged 27.63 ± 5.26 years were evaluated by optoelectronic plethysmography in the supine position with trunk inclination of 45° during quiet breathing and during exercise performance. ResultsIn the comparisons among exercises, VIS promoted a significantly higher inspiratory time and lower mean inspiratory flow compared with FIS. The rating of perceived exertion according to the Borg Scale was significantly higher after the performance of FIS compared with VIS. Regarding asynchrony, none of the exercises caused changes in thoracoabdominal synchrony between the rib cage and abdomen. However, both devices significantly reduced the asynchrony between the pulmonary and abdominal rib cage compared with quiet breathing. ConclusionSMI exercise was equivalent to incentive spirometers and may be an interesting alternative for clinical use in cases in which it is not possible to acquire the devices.

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

Perception of trunk inclination during sitting with feet in contact with the floor.

[Purpose] To clarify the sitting postural control, the influences of several reference sitting positions on the perception of the trunk position while sitting with the feet in contact with the floor and keeping the eyes closed were investigated. [Participants and Methods] Fifteen young healthy volunteers participated in the present study. The perception of the trunk position was evaluated by calculating the absolute error (error magnitude) and constant error (error direction) between the reference trunk position (which the subjects memorized; the reference position) and the position that they adopted when reproducing the reference position (the reproduced position). Eight reference positions were set at 5° increments (from 15° backward inclination [−] to 20° forward inclination [+]). [Results] The reference positions had a significant effect on the absolute error, and the absolute error values at −15° and −10° were significantly smaller than at 20°. However, the reference positions had no effect on the constant error. [Conclusion] The present study revealed that the perception of the trunk position while sitting with the feet in contact with the floor is better when inclining backward than when inclining forward. The perception of the trunk position may be higher in a low-stability position and lower in a high-stability position.

Truncal changes in children with mild limb length inequality: a surface topography study

BackgroundLimb length Inequality (LLI) in children and adults may affect posture, gait, and several truncal parameters, and it can cause spinal scoliosis. In literature, however, there is a paucity of assessment of truncal and spinal changes due to mild LLI in children. This report presents children with LLI, and it aims to provide information in pelvic imbalance, spinal posture, and scoliotic curve, using surface topography analysis which is a novel methodological approach for this condition.Study designThis is an ongoing prospective research study on patient series suffering LLI.Material and methodTwenty children, attending the Scoliosis Clinic of the department, 7 boys, 13 girls, 9–15 years old, range 7.5–15, mean 15.5 years, having mild LLI, were assessed. The LLI was 0.5 to 2 cm, mean 1.2 cm. There was not any post-traumatic LLI. We evaluated the LLI in correlation to pelvic and spinal posture parameters. The 4D Formetric DIERS apparatus (4DF) was used for the surface topography assessment. The following were assessed: in the coronal plane, the coronal imbalance, the pelvic obliquity, the lateral deviation, and the 4DF scoliosis angle; in the sagittal plane, the sagittal imbalance, the 4DF kyphotic angle, the kyphotic apex, the 4DF lordotic angle, the lordotic apex, the pelvic tilt, and the trunk inclination; and in the transverse plane, the pelvis rotation, the pelvic torsion, the surface rotation, and the 4DF vertebral rotation. LLI was measured using a tape. The data were statistically analyzed, and reliability study for the LLI was also performed.Results/discussionThe LLI was statistically significantly correlated to the 4DF reading of pelvis rotation, pelvic tilt (pelvic obliquity), and surface rotation. The scoliometer readings (angle trunk rotation ATR or trunk inclination ATI) in the lumbar region were statistically significantly correlated to the 4DF readings of pelvic tilt (pelvic obliquity). The normally symmetric truncal parameters were also statistically significantly changed (all these deviating from the line of gravity through the vertebral prominence). Interestingly, LLI was not correlated to the scoliosis angle and the scoliometer reading at the lumbar level.The following 4DF readings are presented: in the coronal plane, the coronal imbalance, pelvic obliquity, lateral deviation, and 4DF scoliosis angle; in the sagittal plane, the sagittal imbalance, kyphotic angle, kyphotic apex, lordotic angle, lordotic apex, pelvic tilt, and trunk inclination; and in the transverse plane, the pelvic rotation, pelvic torsion, surface rotation, and vertebral rotation.ConclusionsPrevious studies have reported the results after simulation of LLI in order to evaluate the effects on the pelvic balance and spinal posture parameters. This report is not a LLI simulation study but it presents the effects of mild LLI on truncal changes in the main cardinal planes in children suffering LLI. These changes undoubtedly affect not only the standing truncal posture but also the gait’s economy as well.As mild LLI affects the pelvic balance and spinal posture parameters, our therapeutic approach is that mild LLI (less than 2.0 cm) has to be corrected using shoe elevation, in order to equalize the pelvic obliquity and, consequently, the spinal posture parameters.

Hip-Muscle Activity in Men and Women During Resisted Side Stepping With Different Band Positions.

Weakness or decreased activation of the hip abductors and external rotators has been associated with lower extremity injury, especially in females. Resisted side stepping is commonly used to address hip weakness. Whereas multiple variations of this exercise are used clinically, few data exist regarding which variations to select. To investigate differences in muscle-activation and movement patterns and determine kinematic and limb-specific differences between men and women during resisted side stepping with 3 resistive-band positions. Controlled laboratory study. Laboratory. A total of 22 healthy adults (11 men, 11 women; age = 22.8 ± 3.0 years, height = 171.6 ± 10.7 cm, mass = 68.5 ± 11.8 kg). Participants side stepped with the resistive band at 3 locations (knees, ankles, feet). We collected surface electromyography of the gluteus maximus, gluteus medius, and tensor fascia lata (TFL) for the moving and stance limbs during the concentric and eccentric phases. We also measured trunk inclination, hip and knee flexion, and hip-abduction excursion. Hip-abductor activity was higher in women than in men ( P ≤ .04). The pattern of TFL activity in the stance limb differed by sex. Women performed the exercise in greater forward trunk inclination ( P = .009) and had greater hip excursion ( P = .003). Gluteus maximus and medius activity increased when the band was moved from the knees to the ankles and from the ankles to the feet, whereas TFL activity increased only when the band was moved from the knees to the ankles. Findings were similar for both the stance and moving limbs, but the magnitudes of the changes differed. Compared with placing the band around the ankles, placing the band around the feet for resisted side stepping elicited more activity in the gluteal muscles without increasing TFL activity. This band placement is most appropriate when the therapeutic goal is to activate the muscles that resist hip adduction and internal rotation.

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.

A Method for Bipedal Robot Locomotion Control along an Arbitrary Trajectory

This paper presents an algorithm for stable bipedal walking control along an arbitrary curve. The algorithm starts with a foot planner, which takes a parametrically defined desired path as an input and calculates feet positions and orientations at each step. Zero moment point (ZMP) concept is used for robot stability control. The dynamics of the robot is modeled as a running cart on a table. Given the reference ZMP trajectory, ZMP tracking servo controller based on preview control theory is used to calculate robot’s center of mass (CoM) trajectory. The preview controller is made of three terms: the integral error of ZMP, the state feedback proportional to a current state vector and the preview action which takes into account future values of the desired ZMP position. We propose robot’s state estimator based on linear Kalman filter with measured CoM acceleration and position as system inputs. Swing foot trajectories are calculated using trigonometric functions, since they are simple and can provide zero velocities at contact moments. We put some additional constraints on a system by assuming that there is no forward-backward inclination of the robot trunk and swing foot is always parallel to the ground. To avoid kinematic limits in hip and ankle roll joints we calculate a minimal angle to rotate robot trunk in frontal plane. After position and orientation of robot trunk and swing foot are found we apply inverse kinematics solution for robot legs to get robot joint angles. Finally, joint angles are sent to robot actuators. Software package based on ROS operating system was developed for AR601 robot. Verification tests were executed with robot model in Gazebo simulator. The robot successfully completed series of experiments confirming modelling results.

Does occlusal splint affect posture? A randomized controlled trial

ABSTRACT Objective The aim of this study was to evaluate the effect of an occlusal splint on body posture of intra-articular temporomandibular joint (TMJ) disorders patients. Methods The study was performed on 45 women affected by TMJ disorders divided into an occlusal splint group and a control group. Rasterstereographic recordings were performed at baseline and after 1, 3, and 6 months, in order to analyze the following postural parameters: trunk inclination, cervical and lumbar arrows, kyphotic and lordotic angles, trunk imbalance, pelvic tilt and torsion. Results Regarding the postural parameters in the intragroup analysis, no significant differences were detected. The analysis between the two groups revealed significant differences concerning the cervical arrow, the kyphotic and lordotic angles. Discussion Even if some differences were found between the control and the occlusal splint group, the low range of statistical significance made these results not significant from a clinical point of view.

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.

Kinematics of Rugby Tackling: A Pilot Study With 3-dimensional Motion Analysis

Background: Although improper tackling technique in rugby can affect the outcome of the tackle and lead to head, neck, and shoulder injuries, the effects of the height of the tackle or the side of the leading leg at the time of impact have not been investigated. Hypothesis/Purpose: The purpose was to characterize the trunk orientation at impact during various tackles. It was hypothesized that 3-dimensional motion analysis would be able to capture the critical kinematic differences in the 4 types of tackles studied. Study Design: Controlled laboratory study. Methods: A total of 66 tackles on a tackle bag were recorded among 13 elite rugby players. Four types of tackles were evaluated: the normal shoulder tackle, in which the tackler’s dominant shoulder made impact while the leading foot was on the same side as that shoulder; the low tackle, in which the tackler targeted the lower portion of the tackle bag; the opposite-leg tackle, in which the tackler’s leading leg was on the opposite side as the shoulder making impact; and the low and opposite-leg tackle, which was a combination of the previous 2 types of tackles. The orientation of the trunk at impact was calculated, and 2-way repeated-measures analyses of variance were used to compare the characteristics of these tackles. Results: Trunk inclination at impact was lower in the low tackle than in the normal tackle (P < .01), regardless of the side of the leading leg. Trunk bending to the side of the impacted shoulder was lower in the opposite-leg tackle (P < .01), and these findings were more significant in the normal-height tackles (P < .01). Trunk rotation to the side of the impacted shoulder was lower in the opposite-leg tackles (P < .01) and more significant in the lower-height tackles (P = .03). Conclusion: The 3-dimensional motion capture system was effective in investigating the kinematics of rugby tackling. The kinematics in the low and opposite-leg tackles were significantly different from those in the normal shoulder tackle, which may affect tackle performance and the possible risk of contact injury. Clinical Relevance: When a rugby coach provides tackling instructions to players, it is advantageous to have information about the kinematics of different types of tackles.

The Golf Movement Screen Is Related to Spine Control and X-Factor of the Golf Swing in Low Handicap Golfers.

Gould, ZI, Oliver, JL, Lloyd, RS, Neil, R, and Bull, M. The golf movement screen is related to spine control and x-factor of the golf swing in low handicap golfers. J Strength Cond Res 35(1): 240-246, 2021-The aim of the study was to investigate the association between the golf movement screen (GMS), x-factor, which is the separation between the upper torso and pelvis rotation, and biomechanical movements of the pelvis, thorax, and spine during the backswing and impact of a golf shot in low handicap golfers. In total, 62 golfers were involved in this study (n = 40 male, n = 22 female); the mean age of the sample was 15.4 ± 2.4 years. For the GMS, all subjects were assessed on their movement ability over a total of 10 different exercises. After a thorough warm-up routine of practice swings, each golfer then performed a single trial for biomechanical analysis. Biomechanical data were collected using an electromagnetic tracking system. Four of the 10 exercises had a significant correlation with x-factor (r = 0.25-0.33; p < 0.05). Four exercises had moderate correlations with spine rotation at the top of backswing. Spine side bend had a significant correlation with 9 of the 10 exercises and total GMS score (r = 0.26-0.53, p < 0.05). Movements of the pelvis and thorax at the top of backswing had minimal associations with the GMS. At impact, trunk inclination, thoracic rotation, and squat had small to moderate significant relationships with biomechanical movements (p < 0.05). Movement competency, as measured by the GMS, is associated with important aspects of swing mechanics. In particular, golfers who achieve better scores in the GMS have better spine control and can create a greater x-factor during the golf swing.

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.

Canonical Correlations Between Body Posture Variables and Postural Stability in Children with Scoliosis and Scoliotic Posture

Background: The aim of the study was to analyse the correlation between body posture variables and postural stability in children with scoliosis and scoliotic posture.Methods: Spinal examination photogrammetry used the photometric Moiré method. Based on the angle size of the of spinal curvature, scoliotic posture was determined: 1-9°, and scoliosis: ≥10°. Postural reactions were tested using the Tecnobody ST 310 Plus Stability System platform. Children attended therapy at the Inter-school Centre of Corrective and Compensatory Gymnastics in Starachowice The study was conducted in June 2011. There were 21 children with scoliotic posture (7%) and 7 with scoliosis (25%). Results: In the canonical analysis of body posture variables, the highest share comprised of: trunk inclination angle, alpha angle, chest kyphosis angle, length of lumbar lordosis, length of lumbar lordosis/total spine length, shoulder asymmetry – right higher, shoulder asymmetry – left higher, absolute of pelvis tilt angle, coefficient of shoulder asymmetry relative to C7, primary curvature angle, length of secondary curvature/total spine length, depth of secondary curvature/total spine length. Significance: High values of canonical correlation coefficients, despite lack of significance, indicate the possibility of strong a correlation between body postural variables and postural stability that can be demonstrated with a greater sample size.

Personalized method for self-management of trunk postural ergonomic hazards in construction rebar ironwork

Construction rebar workers face postural ergonomic hazards that can lead to work-related Lower Back Disorders (LBDs), primarily due to their prolonged awkward working postures required by the job. In a previous study, Wearable Inertial Measurement Units (WIMUs)-based Personal Protective Equipment (PPE) was developed to alert workers when their trunk inclination holding time exceeded acceptable thresholds as defined in ISO standard 11226:2000. However, subsequent field testing identified PPE was ineffective for some workers because the adopted ISO thresholds were not personalized and did not consider differences in individual’s response to postural ergonomic hazards. To address this problem, this paper introduces a worker-centric method to assist in the self-management of work-related ergonomic hazards, based on data-driven personalized healthcare intervention. Firstly, personalized information is gathered by providing each rebar ironworker a WIMU-based personalized mobile health (mHealth) system to capture their trunk inclination angle and holding time data. Then, the captured individual trunk inclination holding times are analyzed by a Gaussian-like probability density function, where abnormal holding time thresholds can be generated and updated in response to incoming trunk inclination records of an individual during work time. These abnormal holding time thresholds are then adapted to be used as personalized trunk inclination holding time recommendations for an individual worker to self-manage their working postures, based on their own trunk inclination records. The proposed worker-centric method to assist in the self-management of ergonomic postural hazards leading to LBDs was field tested on a construction site over a three-month duration. The results of the paired t-tests indicate that posture scores evaluated by the Ovako Working Posture Analysis System (OWAS) significantly decrease when the personalized recommendation is applied, while increase again when the personalized recommendation is removed. Based on data-driven personalized healthcare intervention, the results demonstrate the significant potential of the proposed worker-centric self-management method for rebar workers in preventing and controlling postural ergonomic hazards during construction rebar ironwork.

Effects of Increased Gluteus Muscle Activation on Hip and Trunk Kinematics during Single-leg Landing

The gluteus maximus (GM) has a triplanar function at the hip joint. It was hypothesized that increased GM activation before and after foot contact (FC) on landing would affect triplanar hip and trunk kinematics and anterior cruciate ligament (ACL) injury risk. PURPOSE: To examine how increased GM activation before and after FC affect hip angles and trunk inclination during single-leg landing. METHODS: A double-leg drop jump from a 30-cm box, followed by single-leg landing onto a force plate, was performed by 13 males and 15 females in both control (CC) and experimental conditions (EC). In EC, transcutaneous electrical stimulation was applied to increase GM activation immediately before FC and during single-leg landing. Kinetic and kinematic data were collected using a force plate and 3-dimensional electromagnetic motion tracking system, respectively. Hip joint angles and sacrum and thorax inclination angles in space on FC, peak ground reaction force (GRFpk), and peak knee extensor moment (KEMpk) during single-leg landing were calculated. Comparisons were performed using two-way (sex×conditions) repeated measures analysis of variance with a significance level < .05. RESULTS: The hip joint exhibited more abduction (EC vs. CC at FC, GRFpk, and KEMpk, respectively: -13.2 ± 7.8° vs. -9.5 ± 6.3°, -8.9 ± 7.7° vs. -4.9 ± 6.8°, -3.3 ± 8.9° vs. -.2 ± 6.5°) and external rotation (-14.8 ± 8.5° vs. -9.8 ± 9.9°, -8.0 ± 3.6° vs. -3.6 ± 9.7°, -6.1 ± 9.7° vs. -1.6 ± 11.2°) at all time points in EC than in CC. The sacrum showed more lateral inclination toward the supporting leg at all time points (14.3 ± 6.4° vs. 11.1 ± 6.4°, 12.1 ± 6.4° vs. 9.0 ± 6.1°, 8.9 ± 7.1° vs. 6.7 ± 6.2°) and more erect position at KEMpk in EC (-1.0 ± 10.6°) than at CC (-4.6 ± 10.5°). No significant differences were observed in thoracic inclination angles. No significant interactions were observed among all variables. CONCLUSIONS: Increased GM before and after FC on single- leg landing may have positive effects on frontal and transverse plane hip motion to reduce ACL injury risk. However, excessive GM activation may result in excessive trunk lean toward the supporting leg and more erect position, which increase risk for ACL loading. Thus, appropriate GM activation is necessary to protect the ACL during single-leg landing.