Intra- and inter-rater reliability of joint range of motion tests using tape measure, digital inclinometer and inertial motion capturing

Background In clinical practice range of motion (RoM) is usually assessed with low-cost devices such as a tape measure (TM) or a digital inclinometer (DI). However, the intra- and inter-rater reliability of typical RoM tests differ, which impairs the evaluation of therapy progress. More objective and reliable kinematic data can be obtained with the inertial motion capture system (IMC) by Xsens. The aim of this study was to obtain the intra- and inter-rater reliability of the TM, DI and IMC methods in five RoM tests: modified Thomas test (DI), shoulder test modified after Janda (DI), retroflexion of the trunk modified after Janda (DI), lateral inclination (TM) and fingertip-to-floor test (TM). Methods Two raters executed the RoM tests (TM or DI) in a randomized order on 22 healthy individuals while, simultaneously, the IMC data (Xsens MVN) was collected. After 15 warm-up repetitions, each rater recorded five measurements. Findings Intra-rater reliabilities were (almost) perfect for tests in all three devices (ICCs 0.886–0.996). Inter-rater reliability was substantial to (almost) perfect in the DI (ICCs 0.71–0.87) and the IMC methods (ICCs 0.61–0.993) and (almost) perfect in the TM methods (ICCs 0.923–0.961). The measurement error (ME) for the tests measured in degree (°) was 0.9–3.3° for the DI methods and 0.5–1.2° for the IMC approaches. In the tests measured in centimeters the ME was 0.5–1.3cm for the TM methods and 0.6–2.7cm for the IMC methods. Pearson correlations between the results of the DI or the TM respectively with the IMC results were significant in all tests except for the shoulder test on the right body side (r = 0.41–0.81). Interpretation Measurement repetitions of either one or multiple trained raters can be considered reliable in all three devices

Erhöhung der Übertragungsfähigkeit von Mittelspannungsnetzen durch stromabhängige Spannungsregelung in Umspannwerken und spannungsanhängige Blindleistungsregelung in dezentralen Einspeiseanlagen

Die vorliegende Arbeit beschreibt Möglichkeiten, die Übertragungsfähigkeit von ländlichen Mittelspannungsnetzen sowohl für die Versorgung von Verbraucherlasten als auch für den Abtransport dezentraler Erzeugungsleistungen zu erhöhen. Es wird einerseits eine wirkstromabhängige Spannungsregelung U(Iw) im Umspannwerk betrachtet, wobei die Wirkleistungsrichtung im Umspanner HS/MS mitberücksichtigt wird. Andererseits wird die Möglichkeit von spannungsabhängigen Blindleistungsregelungen Q(U) in dezentralen Erzeugungsanlagen genutzt. Wechselrichter und Synchrongeneratoren leisten dabei, abhängig von der eigenen Betriebsspannung, mit Blindleistungslieferung oder Blindleistungsbezug, ihren Beitrag zur dezentralen Spannungshaltung. Die Wirksamkeit der beiden Maßnahmen wird mit Lastflussberechnungen in einem Musternetz und in einem realen Mittelspannungsnetz ermittelt und dargestellt. Im realen Netz werden die Berechnungsergebnisse den Ergebnissen von betrieblichen Messungen gegenübergestellt. Es werden Kennlinien für die Spannungsregelung erarbeitet. Das Betriebsspannungsband UN ±10% wird in Nieder- und Mittelspannungsbereiche aufgeteilt. Die regulatorischen Rahmenbedingungen für dezentrale Erzeugungsanlagen werden beschrieben

Comparison of Joint Kinematics in Transition Running and Isolated Running in Elite Triathletes in Overground Conditions

Triathletes often experience incoordination at the start of a transition run (TR); this is possibly reflected by altered joint kinematics. In this study, the first 20 steps of a run after a warm-up run (WR) and TR (following a 90 min cycling session) of 16 elite, male, long-distance triathletes (31.3 ± 5.4 years old) were compared. Measurements were executed on the competition course of the Ironman Frankfurt in Germany. Pacing and slipstream were provided by a cyclist in front of the runner. Kinematic data of the trunk and leg joints, step length, and step rate were obtained using the MVN Link inertial motion capture system by Xsens. Statistical parametric mapping was used to compare the active leg (AL) and passive leg (PL) phases of the WR and TR. In the TR, more spinal extension (~0.5–1°; p = 0.001) and rotation (~0.2–0.5°; p = 0.001–0.004), increases in hip flexion (~3°; ~65% AL−~55% PL; p = 0.001–0.004), internal hip rotation (~2.5°; AL + ~0–30% PL; p = 0.001–0.024), more knee adduction (~1°; ~80–95% AL; p = 0.001), and complex altered knee flexion patterns (~2–4°; AL + PL; p = 0.001–0.01) occurred. Complex kinematic differences between a WR and a TR were detected. This contributes to a better understanding of the incoordination in transition running

Comparison of joint kinematics in transition running and isolated running in elite triathletes in overground conditions

Triathletes often experience incoordination at the start of a transition run (TR); this is possibly reflected by altered joint kinematics. In this study, the first 20 steps of a run after a warm-up run (WR) and TR (following a 90 min cycling session) of 16 elite, male, long-distance triathletes (31.3 ± 5.4 years old) were compared. Measurements were executed on the competition course of the Ironman Frankfurt in Germany. Pacing and slipstream were provided by a cyclist in front of the runner. Kinematic data of the trunk and leg joints, step length, and step rate were obtained using the MVN Link inertial motion capture system by Xsens. Statistical parametric mapping was used to compare the active leg (AL) and passive leg (PL) phases of the WR and TR. In the TR, more spinal extension (~0.5–1°; p = 0.001) and rotation (~0.2–0.5°; p = 0.001–0.004), increases in hip flexion (~3°; ~65% AL−~55% PL; p = 0.001–0.004), internal hip rotation (~2.5°; AL + ~0–30% PL; p = 0.001–0.024), more knee adduction (~1°; ~80–95% AL; p = 0.001), and complex altered knee flexion patterns (~2–4°; AL + PL; p = 0.001–0.01) occurred. Complex kinematic differences between a WR and a TR were detected. This contributes to a better understanding of the incoordination in transition running

Balance Stability and Cervical Spine Range of Motion While Wearing a Custom-Made Mandibular Splint with Special Consideration of the Sex

Introduction: An altered dental occlusion can also affect balance stability or mobility. Thus, the aim of this study was to examine whether wearing a mandibular splint, which retains the occlusion close to the centric occlusion, can increase or decrease balance stability and the range of motion (ROM) of the cervical spine as opposed to the habitual occlusion, and if there is a difference between men and women. Material and methods: In this study, 41 male (34.7 ± 11.4 years) and 50 female subjects (29.3 ± 12.7 years) participated. Cervical spine ROM was recorded using the Zebris CMS 70P system. For balance stability, a pressure measuring platform integrated into the treadmill system (FDM-T) of the company Zebris® Medical GmbH was used. Here, the area of the ellipse and the length of the Center of Pressure (CoP) was recorded whilst in the bipedal and unipedal stance. Results: The sex comparison showed significant differences for the area of the ellipse of the right leg and ROM extension in the habitual occlusion: females showed a better balance stability and a larger ROM extension. When wearing the splint, only the CoP of the left leg was significant with a better balance stability in female subjects. Within the male subjects, the ellipse area in the bipedal and unipedal (left/right) stance showed mostly significant reductions, while the rotation left and right as well as the lateral flexion (left/right) improved when wearing the splint. Female subjects, when wearing the splint, showed a significant decrease of the ellipse area and the CoP length when standing on either leg. Flexion, rotation to the right and lateral flexion to the left/right, all increased significantly. Conclusion: Wearing a splint that keeps the jaw close to the centric relation improved balance stability and increased the ROM of the cervical spine for both male and female subjects. Women may have marginally different basic balance stability strategies than men, with regard to bipedal and unipedal standing. Nevertheless, there are scarcely any differences between the two sexes in the adaptation when wearing a splint. Changing the jaw relation in healthy adults can possibly support the release of movement potentials that simplify the performance of everyday activities or sports movements

The movement profile of habitual vacuuming as a cyclic movement - a pilot study

Background: Vacuum cleaning, which is associated with musculoskeletal complaints, is frequently carried out in private households and by professional cleaners. The aim of this pilot study was to quantify the movements during habitual vacuuming and to characterize the movement profile with regard to its variability. Methods: The data were collected from 31 subjects (21 f/10 m) using a 3D motion analysis system (XSens). Eight vacuum cleaners were used to vacuum polyvinyl chloride (PVC) and carpet floors. In 15 joints of the right upper extremity, the trunk and the lower extremities, Principal Component Analysis was used to determine the predominantly varying joints during vacuuming. Results: The movements of the trunk and the lower extremities were relatively constant and, therefore, had less influence. The shoulder, elbow and wrist joints were identified as joints that can be decisive for the movement profile and that can be influenced. These joints were represented in the course of the vacuuming cycle by the mean movement with its standard deviation. Conclusion: In summary, the generalization of a movement profile is possible for the trunk and the lower extremities due to the relative homogeneity. In future it will be necessary to identify factors influencing variability in order to draw conclusions about movement ergonomics

Differences in upper body posture between patients with lumbar spine syndrome and healthy individuals under the consideration of sex, age and BMI

Abstract Background Work-related forced postures, such as prolonged standing work, can lead to complaints in the lower back. Current research suggests that there is increased evidence of associations between patients with low back pain (LBP) and reduced lordosis in the lumbar spine and generally less spinal tilt in the sagittal plane. The aim of this study is to extend the influence of LBP to other parameters of upper body posture in standing, taking into account the rotational and frontal planes. Methods The study included a no-LBP group (418 males, 412 females, aged 21–65 years) and an LBP group (138 subjects: 80 females, 58 males, aged 18–86 years) with medically diagnosed lumbar spine syndrome (LSS). The “ABW BodyMapper” back scanner from ABW GmbH in Germany was used for posture assessment using video raster stereography. Statistical analyses employed two-sample t-tests or Wilcoxon-Mann-Whitney-U tests to assess the relationship between the LBP/no-LBP groups and back posture parameters. Linear and logarithmic regressions were used with independent variables including group, sex, height, weight and body mass index (BMI). Significance level: α = 0.05 (95% confidence). Results The regression analysis showed that sagittal parameters of the spine (sagittal trunk decline, thoracic and lumbar bending angle, kyphosis and lordosis angles) depend primarily on sex, age, BMI, height and/or weight but not on group membership (LBP/no-LBP). In the shoulder region, a significant dependency between group membership and scapular rotation was found. In the pelvic region, there were only significant dependencies in the transverse plane, particularly between pelvic torsion and BMI, weight, height and between pelvic rotation and group membership, age and sex. Conclusion No difference between the patients and healthy controls were found. In addition, sex appears to be the main influencing factor for upper body posture. Other influencing factors such as BMI, height or weight also seem to have a significant influence on upper body posture more frequently than group affiliation

Influence of dental occlusion conditions on plantar pressure distribution during standing and walking – a gender perspective

The aim of this study was to investigate gender-specific influences of different symmetric and asymmetric occlusion conditions on postural control during standing and walking. The study involved 59 healthy adult volunteers (41 f/19 m) aged between 22 and 53 years (30.2 ± 6.3 years). Postural control measurements were carried out using a pressure plate by measuring plantar pressure distribution during standing and walking test conditions. Seven different occlusion conditions were tested. Prior to a MANOVA model analysis, the relationship between the two test conditions were checked using a factor analysis with a varying number of factors (between 2 and 10). The plantar pressure distributions during walking and standing are independent test conditions. The coefficient of variance across all variables between the conditions and genders was not significant: t(46) = 1.51 (p = 0.13). No statement can be made whether, or not, the influence of gender is greater than the influence of the conditions. Healthy male and female test subjects did not show any difference between seven occlusion conditions on the plantar pressure distribution while standing or walking. No differences between the genders were found for any of the investigated variables. In contrast to custom-made occlusion splints, simple cotton rolls appear not to influence the neuromuscular system in a systematic manner

Body Weight Distribution and Body Sway in Healthy Female Adults Aged between 51 and 60 Years in Germany—Standard Values

Background: In order to determine possible pathological deviations in body weight distribution and body sway, it is helpful to have reference values for comparison: gender and age are two main influencing factors. For this reason, it was the aim of the present study to present reference values for women between 51 and 60 years of age. Methods: For this study, 101 subjectively healthy female Germans aged between 51 and 60 years (55.16 ± 2.89 years) volunteered and were required to stand in a habitual posture on a pressure measuring platform. Results: The average BMI of this age group was 25.02 ± 4.55 kg/m². The left and right foot showed an almost evenly balanced load distribution with a median load of 52.33% on the left foot [tolerance interval (TR) 38.00%/68.03%; confidence interval (CI) 51.00%/53.33%] and 47.67% on the right foot [TR 31.97%/62.00%; CI 46.67%/49.00%]. The measured median load of the forefoot was 33.33% [TR 21.37%/54.60%; CI 30.67%/36.00%] and that of the rear foot was 66.67% [TR 45.50%/78.63%; CI 64.00%/69.33%]. The median body sway in the frontal plane was 11 mm [TR 5.70 mm/26.30 mm; CI 10.00 mm/11.67 mm] and that of the sagittal plane was 16 mm [TR 7.37 mm/34.32 mm; CI 14.67 mm/18.67 mm]. The median ellipse area was 1.17 cm² [TR 0.29 cm²/4.96 cm²; CI 0.98 cm²/1.35 cm²], the median ellipse width was 0.91 cm [TR 0.42 cm/1.9 cm; CI 0.84 cm/1.02 cm] and its height was 0.40 cm [TR 0.22 cm/0.89 cm; CI 0.38 cm/0.43 cm]. Conclusions: The left-to-right ratio is almost balanced. The load distribution of the forefoot to the rear foot is approximately 1:2. The median body sway values for the frontal and sagittal planes (11 and 16 mm, respectively) agree with other values. The values for the height, body weight and the BMI are comparable to the values of average German women at this age; therefore, the measured values show a presentable cross section of women in the 51–60 age group in Germany. The present data can be used as a basis for women aged 51–60 years and can support the detection of possible dysfunctions as well as injury prevention in the parameters of postural control