INFLUENCE OF THE STEP LENGTH AND POSITION OF THE FRONT KNEE ON THE LOAD CONDITIONS OF THE KNEE AND HIP DURING LUNGES

The aim of this study was to quantify the differences in the loading conditions of the lunge strength exercise at different step lengths and different tibia angles of the front leg. Eleven subjects performed lunges with 25 % body mass (BM) barbell extra load on two force plates. The movement was recorded with a motion capture system. The angles and the forces were calculated using inverse dynamics. A larger tibia angle led to a smaller ROM of the front knee, a larger ROM of the rear knee and hip, whereas a larger step length decreased the ROM of the rear knee and hip. A larger tibia angle resulted in a decreased moment in the front knee, front and rear hip and an increased moment in the rear knee. This possibility for varying the angles and corresponding moments allows coaches and therapists to adapt the lunge to an efficient exercise for strength training

Occupational sitting behaviour and its relationship with back pain – A pilot study

AbstractNowadays, working in an office environment is ubiquitous. At the same time, progressively more people suffer from occupational musculoskeletal disorders. Therefore, the aim of this pilot study was to analyse the influence of back pain on sitting behaviour in the office environment.A textile pressure mat (64-sensor-matrix) placed on the seat pan was used to identify the adopted sitting positions of 20 office workers by means of random forest classification. Additionally, two standardised questionnaires (Korff, BPI) were used to assess short and long-term back pain in order to divide the subjects into two groups (with and without back pain). Independent t-test indicated that subjects who registered back pain within the last 24 h showed a clear trend towards a more static sitting behaviour. Therefore, the developed sensor system has successfully been introduced to characterise and compare sitting behaviour of subjects with and without back pain

Prevalence of renal impairment and its association with cardiovascular risk factors in a general population: results of the Swiss SAPALDIA study

Background. Impaired renal function is evolving as an independent marker of the risk of cardiovascular morbidity and mortality. Little is known about the prevalence of impaired renal function and its relationship to cardiovascular risk factors in the Swiss general population. Methods. SAPALDIA comprises a random sample of the Swiss population established in 1991, originally to investigate the health effects of long-term exposure to air pollution. Participants were reassessed in 2002/3 and blood measurements were obtained (n = 6317). Renal function was estimated using the Cockcroft-Gault equation and the modified MDRD (four-component) equation incorporating age, race, gender and serum creatinine level. Results. The estimated prevalence of impaired renal function [estimated glomerular filtration rate <60 ml/min/1.73 m2] differed substantially between men and women, particularly at higher ages, and amounted to 13% [95% confidence interval (CI) 10-16%] and 36% (95% CI 32-40%) in men and women, respectively, of 65 years or older. Smoking, obesity, blood lipid levels, high systolic blood pressure and hyperuricaemia were all more common in men when compared with women. These cardiovascular risk factors were also associated independently with creatinine in both women and men. Women were less likely to receive cardiovascular drugs, in particular angiotensin-converting enzyme inhibitors and β-blockers, when compared with men of the same age. Conclusion. Moderate renal impairment seems to be prevalent in the general population, with an apparent excess in females which is not explained by conventional cardiovascular risk factors. The unexpected finding questions the validity of the prediction equations, in particular in female

Structure of the pre-60S ribosomal subunit with nuclear export factor Arx1 bound at the exit tunnel

Pre-ribosomal particles evolve in the nucleus through transient interaction with biogenesis factors, before export to the cytoplasm. Here, we report the architecture of the late pre-60S particle purified from Saccharomyces cerevisiae through Arx1, a nuclear export factor with structural homology to methionine aminopeptidases, or its binding partner Alb1. Cryo-electron microscopy reconstruction of the Arx1-particle at 11.9 Å resolution reveals regions of extra densities on the pre-60S particle attributed to associated biogenesis factors, confirming the immature state of the nascent subunit. One of these densities could be unambiguously assigned to Arx1. Immuno-electron microscopy and UV cross-linking localize Arx1 close to the ribosomal exit tunnel in direct contact with ES27, a highly dynamic eukaryotic rRNA expansion segment. The binding of Arx1 at the exit tunnel may position this export factor to prevent premature recruitment of ribosome-associated factors active during translation

Veränderte Spielregeln : Finanzberatung

Der Artikel beleuchtet am Beispiel der Privaten Finanzplanung - deren Kennzeichen es ja ist, finanzielle Planungsrechnungen in die Zukunft zu erstellen -, wie ein Berater auf sich verändernde oder sich abzeichnende gesetzliche Rahmenbedingungen reagieren sollte und welche Aufklärungspflichten er gegenüber seinen Kunden hat

In Vivo Spinal Posture during Upright and Reclined Sitting in an Office Chair

Increasing numbers of people spend the majority of their working lives seated in an office chair. Musculoskeletal disorders, in particular low back pain, resulting from prolonged static sitting are ubiquitous, but regularly changing sitting position throughout the day is thought to reduce back problems. Nearly all currently available office chairs offer the possibility to alter the backrest reclination angles, but the influence of changing seating positions on the spinal column remains unknown. In an attempt to better understand the potential to adjust or correct spine posture using adjustable seating, five healthy subjects were analysed in an upright and reclined sitting position conducted in an open, upright MRI scanner. The shape of the spine, as described using the vertebral bodies’ coordinates, wedge angles, and curvature angles, showed high inter-subject variability between the two seating positions. The mean lumbar, thoracic, and cervical curvature angles were 29±15°, -29±4°, and 13±8° for the upright and 33±12°, -31±7°, and 7±7° for the reclined sitting positions. Thus, a wide range of seating adaptation is possible through modification of chair posture, and dynamic seating options may therefore provide a key feature in reducing or even preventing back pain caused by prolonged static sitting

Wheelchair Tilt-in-Space and Recline Functions: Influence on Sitting Interface Pressure and Ischial Blood Flow in an Elderly Population

Pressure ulcers (PUs) result from localised injury to the skin and underlying tissue and usually occur over a bony prominence as a result of pressure, often in combination with shear forces. Both pressure magnitude and duration are thought to be key risk factors in the occurrence of PUs, thus exposing wheelchair-bound subjects to high risk of PU development. As a result, wheelchairs that incorporate tilt-in-space and recline functions are routinely prescribed to redistribute pressure away from their ischial tuberosities. The goal of this study was to analyse the role of full-body tilt and recline angles in governing sitting interface pressure and blood circulation parameters in elderly subjects and thereby investigate the efficacy of tilt-in-space wheelchairs for aiding pressure relief activity. Sitting interface pressure and ischial blood flow parameters were examined in 20 healthy elderly subjects while seated in a tilt-in-space and recline wheelchair. Five different angles of seat tilt (5°, 15°, 25°, 35°, and 45°) were assessed in combination with three different angles of backrest recline (5°, 15°, and 30°). The results of the study show that when compared to the upright reference posture, every position (except 15°T/5°R) resulted in a significant decrease in sitting interface pressure. Ischial blood flow also showed significant increases at four different positions (45°T/15°R, 15°T/30°R, 35°T/30°R, and 45°T/30°R) but only at larger tilt-in-space and recline angles. The results therefore suggest that small tilt-in-space and recline angles are indeed able to reduce sitting interface pressures, whereas changes in ischial blood flow only occur at larger angles. In the literature, cell deformation is thought to be dominant over tissue ischemia in the development of tissue necrosis and PUs. Therefore, together with our findings it can be concluded that frequently undertaking small adjustments in tilt-in-space and recline angle might be important for preventing cell deformation and any associated cell necrosis. Larger angles of tilt-in-space and recline seem to support blood flow returning to the tissues, which is likely to play a positive role in healing damaged tissue

Feedback improves compliance of pressure relief activities in wheelchair users with spinal cord injury

STUDY DESIGN Prospective cross-sectional pre-post pilot study. OBJECTIVES This pilot study aimed to evaluate the potential for improving pressure relief behaviour in wheelchair users with spinal cord injury (SCI) using a novel feedback system based on textile pressure sensor technology. SETTING In- and out-patient clinic of the Spinal Cord Injury Center, Balgrist University Hospital, Zurich, Switzerland. METHODS Nine wheelchair users with SCI (3 females, 50 ± 12 years of age, 2 tetra- and 7 paraplegics) were equipped with a feedback system (sensomative$_{wheelchair}$) for three continuous weeks. The system consists of a textile pressure mat and a mobile smartphone application that reminds participants to perform missing pressure reliefs during regular and unobserved wheelchair usage in a customized manner. Pressure reliefs were detected using a subject-specific random forest classifier. Improvements of relief quality, duration and frequency were analysed by comparing week 1 (baseline) with no feedback, i.e., only pressure data recorded, against week 2 (with feedback). Carry-over effects of improved relief behaviour were studied in week 3 (no feedback, pressure data only recorded). RESULTS All participants increased their relief frequency and performed in median 82% (IQRs: 55%-99%) of the required reliefs while using the feedback system, whereas the median relief frequency was only 11% (IQRs: 10%-31%) during the baseline condition. Every participant who did not perform reliefs of sufficient duration (based on the recommendations of the therapist) during week 1 showed a significant improvement while using the feedback system. CONCLUSION Subject-specific feedback using the novel feedback system may have the potential for improving the regularity of an individual's relief activities, and may ultimately be an instrument for reducing the risk of developing pressure ulcers