Postural regulation and stability with acoustic input in normal-hearing subjects.

BACKGROUND: Postural regulation is based on complex interactions among postural subsystems. The auditory system too appears to have an influence on postural control. OBJECTIVE: The aim of this study was to measure the influence of auditory input on postural control and to gain a deeper understanding of the interactions between auditory input and postural subsystems including subjective aspects. MATERIALS AND METHODS: In 30 healthy normal-hearing subjects, postural regulation and stability was measured with the Interactive Balance System (IBS; Inc. neurodata GmbH, Wien, Österreich) in 8 test positions with noise (frontal presentation) and plugged without noise. The IBS is an electrophysiological measurement device that measures postural control at the product level (e.g., stability, weight distribution) and the mechanisms of postural subsystems at the process level based on frequency-oriented fast-Fourier analysis of force-time relation. RESULTS: At the process level, we found a relevant reduction (ηp2 ≥ 0.10) of postural regulation with noise in the frequency bands F1 (visual and nigrostriatal system ηp2 = 0.122) and F2-4 (peripheral vestibular system ηp2 = 0.125). At the product level, the weight distribution index (WDI) parameter showed a relevant increase with noise (ηp2 = 0.159). No difference between the auditory conditions was found for postural stability (parameter: stability indicator, ST). Substantial interindividual variations in the subjective estimation of the influence of auditory inputs on stability were observed. CONCLUSION: In this study, a shift in the activity of postural subsystems was observed with auditory input, while no difference was seen in ST. This leads to new insights into mechanisms of audiovestibular interaction.

[Postural regulation and stability with acoustic input in normal hearing subjects. German version]. / Posturale Regulation und Stabilität unter akustischem Input bei Normalhörenden.

BACKGROUND: Postural regulation is based on complex interactions among postural subsystems. The auditory system too appears to have an influence on postural control. OBJECTIVE: The aim of this study was to measure the influence of auditory input on postural control and to gain a deeper understanding of the interactions between auditory input and postural subsystems including subjective aspects. MATERIALS AND METHODS: In 30 healthy normal-hearing subjects, postural regulation and stability was measured with the Interactive Balance System (IBS; Inc. neurodata GmbH, Wien, Österreich) in 8 test positions with noise (frontal presentation) and plugged without noise. The IBS is an electrophysiological measurement device that measures postural control at the product level (e.g., stability, weight distribution) and the mechanisms of postural subsystems at the process level based on frequency-oriented fast-Fourier analysis of force-time relation. RESULTS: At the process level, we found a relevant reduction (ηp2 ≥ 0.10) of postural regulation with noise in the frequency bands F1 (visual and nigrostriatal system ηp2 = 0.122) and F2-4 (peripheral vestibular system ηp2 = 0.125). At the product level, the weight distribution index (WDI) parameter showed a relevant increase with noise (ηp2 = 0.159). No difference between the auditory conditions was found for postural stability (parameter: stability indicator, ST). Substantial interindividual variations in the subjective estimation of the influence of auditory inputs on stability were observed. CONCLUSION: In this study, a shift in the activity of postural subsystems was observed with auditory input, while no difference was seen in ST. This leads to new insights into mechanisms of audiovestibular interaction.

Influence of hearing on vestibulospinal control in healthy subjects.

BACKGROUND: Balance control is based on multisensory interaction. In addition to vestibular, proprioceptive and visual information, it seems that auditory input also plays an important role. OBJECTIVES: The aim of the study was to investigate the effect of hearing on vestibulospinal coordination and to obtain deeper knowledge about mechanisms of audiovestibular interaction. MATERIALS AND METHODS: In normal hearing, healthy subjects who performed the Unterberger (Fukuda) stepping test with and without frontal presentation of noise, the distance of displacement, the angle of displacement and the angle of rotation were measured by means of ultrasound based cranio-corpo-graphy (CCG). Additionally, subjective estimation of the effect of auditory input was compared to objective test results. RESULTS: In the noise condition, there was a significant improvement in the distance of displacement (mean with noise 66.9 cm± 33.5 standard deviation, SD, mean without noise 77.0 cm±32.7 SD, p< 0.001) and in the angle of rotation (mean with noise 14.2°± 10.1 SD, mean without noise 28.3°± 20.2 SD, p< 0.001), while no difference was found within the conditions regarding the angle of displacement (mean with noise 29.1°± 33.5 SD, mean without noise 30.0°± 34.0 SD, p= 0.641). Side-specific analysis revealed a positive correlation between angle of displacement and angle of rotation in the condition without noise (Spearman r = 0.441, p< 0.001). The rate of agreement between subjective estimation of noise influence and objective test results ranged between only 43% and 63%, depending on the question and endpoint. CONCLUSION: Hearing had a clearly beneficial effect of auditory inputs on vestibulospinal coordination, especially for distance of displacement and angle of rotation.

[Influence of hearing on vestibulospinal control in healthy subjects. German version]. / Einfluss des Hörens auf die vestibulospinale Kontrolle bei gesunden Probanden.

BACKGROUND: Balance control is based on multisensory interaction. In addition to vestibular, proprioceptive and visual information, it seems that auditory input also plays an important role. OBJECTIVES: The aim of the study was to investigate the effect of hearing on vestibulospinal coordination and to obtain deeper knowledge about mechanisms of audiovestibular interaction. MATERIALS AND METHODS: In normal hearing, healthy subjects who performed the Unterberger (Fukuda) stepping test with and without frontal presentation of noise, the distance of displacement, the angle of displacement and the angle of rotation were measured by means of ultrasound based cranio-corpo-graphy (CCG). Additionally, subjective estimation of the effect of auditory input was compared to objective test results. RESULTS: In the noise condition, there was a significant improvement in the distance of displacement (mean with noise 66.9 cm ± 33.5 standard deviation, SD, mean without noise 77.0 cm ± 32.7 SD, p < 0.001) and in the angle of rotation (mean with noise 14.2°â€¯± 10.1 SD, mean without noise 28.3°â€¯± 20.2 SD, p < 0.001), while no difference was found within the conditions regarding the angle of displacement (mean with noise 29.1°â€¯± 33.5 SD, mean without noise 30.0°â€¯± 34.0 SD, p = 0.641). Side-specific analysis revealed a positive correlation between angle of displacement and angle of rotation in the condition without noise (Spearman r = 0.441, p < 0.001). The rate of agreement between subjective estimation of noise influence and objective test results ranged between only 43% and 63%, depending on the question and endpoint. CONCLUSION: Hearing had a clearly beneficial effect of auditory inputs on vestibulospinal coordination, especially for distance of displacement and angle of rotation.

[Reconstruction of the medial patellofemoral ligament after lower-leg amputation]. / MPFL-Plastik nach Unterschenkelamputation.

The reconstruction of the medial patellofemoral ligament has been an increasingly popular approach for patellar instability over the last ten years. It is a conglomeration of symptoms with varying degree of severity. For pinpointed surgery planning, magnetic resonance imaging is now the obligate diagnosic tool. Therefore, in the preoperative stage, collateral pathology can be observed.

Experimental Arthritis in the Rat Induced by the Superantigen Staphylococcal Enterotoxin A.

The pathogenesis of rheumatoid arthritis (RA) is incompletely understood. Human endogenous retroviruses (HERVs) and their superantigenic envelope protein (env) have been implicated in the pathogenesis of RA. In the present investigation, the arthritogenic potential of the superantigen staphylococcal enterotoxin A (SEA) has been investigated. In the present investigation, the bacterial superantigen staphylococcal enterotoxin A (SEA) was injected into the right knee joint of 15 Lewis rats. Further nine animals received saline. Animals were sacrificed one, five and 10 days after the injection, respectively. The antigens CD3, CD4, CD8, MHC class I, MHC class II, Pax5 and CD138 were investigated by immunohistochemistry on cryo-sections. After intra-articular SEA injection, the inflammation was initially dominated by CD8+ T cells. In the course of the investigation, the numbers of CD4+, Pax5+, CD138+ and MHC class II+ cells increased. CD3 was expressed in low numbers as compared to CD8. After saline injection, no similar inflammatory response has been detected. The arthritis induced by the superantigen SEA may be a novel model for inflammatory joint diseases, that is rheumatoid arthritis or juvenile idiopathic arthritis.

[Fast Response Training in Youth Soccer Players]. / Hochreaktives Training bei jugendlichen Fußballspielern.

BACKGROUND: Injuries of the knee and ankle joint are a serious ongoing problem in soccer. Although there is a variety of prevention programmes, a significant reduction of severe knee injuries has not been observed. Therefore, current strategies for diagnostics and training need to be re-evaluated. OBJECTIVE: Our study aimed to test a totally new intervention strategy (fast response training on the SpeedCourt). The efficiency of this method was evaluated with youth soccer athletes. MATERIALS AND METHODS: 24 young male class A athletes (mean age 18.0 ±â€Š0.7 years) of a local soccer team underwent SpeedCourt training for 7 weeks (1 training session per week = TS) during the regular season of competition. TS contained life-kinetic elements (time of exercise: 15 - 30 seconds, break: 2 minutes) and included a warm-up phase (15 minutes) and fast response training on the SpeedCourt (30 minutes). The players were tested on the SpeedCourt with different tests (Counter Movement Jump (CMJ), shuttle run, tapping, 10-second sprint) before and after the training programme. RESULTS: The univariate single-factor analysis of variance showed significant improvements in all test parameters (η(2)> 0.10). The range varied between η(2) = 0.106 (time of ground contact right leg) und η(2) = 0.730 (reaction time right leg). We did not find any relevant correlations between the tests and parameters. The number of injury-related accidents involving the lower extremities was reduced by about 50 % during defined periods of time. CONCLUSION: Our data revealed that training with fast responses at the SpeedCourt system clearly improved speed and speed strength performance of young soccer athletes, which is remarkable given the low intensity of influences (one TS per week). The increase in performance was accompanied by a significant reduction of the injury rate.

[How Valid is the Performance Diagnostic in Soccer?]. / Wie valide ist die Leistungsdiagnostik im Fußball?

BACKGROUND: Assessments of physical and physiological performance tests in soccer sports are still unspecific yet. There is also a lack of scientific validation using those as a "golden standard". Concerning match performance a large deficit also exist in sports and medical science. OBJECTIVE: The aim and purpose of this multicentric and prospective diagnostic study was to evaluate the validity of current established and recommended diagnostic tests for endurance and match performance (golden standard: real time of playing) in soccer. MATERIALS AND METHODS: In a prospective study protocol two German soccer teams from the fourth (n = 22) and third (n = 24) national league first underwent different tests of performance and diagnostics ahead of the competition season (tapping, drop jump, counter movement jump, speed dribbling, treadmill running test). Afterwards, match performance of each athlete was assessed by real time of playing (as a surrogate parameter) during the half season (14 and 25 matches). We finally compared test parameters with the match performance in a linear regression analysis. RESULTS: Our analysis showed no statistical relevant relationship between test parameters and match performance (r(2) < 0.10). Only the assessment in maximum of relative oxygen uptake during the treadmill test for endurance was associated with a higher amount of variance (12%). CONCLUSIONS: According to the study results there is no relevant and valid correlation between current established diagnostic tests in soccer sport and sport-specific performance. The time of real engagement during a match might be associated with a quality of performance for the single athlete. Therefore, the assessment of this match activity is the most important parameter for improving diagnostic tests in soccer. The existence of a "golden standard" is essential for validation of any tests and parameters and the development of new specific assessments. At the moment, physical performance tests have no scientific evidence in soccer sports.

[Intraobserver reliability of the Handball-specific complex test (HBKT)]. / Intraobserverreliabilität des handballspezifischen Komplextests (HBKT).

BACKGROUND: There are clearly no complex and sports-specific tests in handball. So far, no specific complex test has been developed and verified for its intraobserver reliability (IR). OBJECTIVE: The aim of this study was to determine the IR of the Handball-specific complex test (HBKT). METHODS: The HBKT was applied twice at an interval of two days to two teams of the German Third League (n = 30; age 25.7 ±â€Š3.9 years, range: 19 - 33 years). Within the HBKT, the stress parameters lactate and heart rate as well as the loading parameters time, throwing velocity and number of errors were collected. RESULTS: Overall, 23 % (3/13) of the stress parameters showed a high relative [intraclass correlation coefficient (ICC) > 0.75] and absolute [coefficient of variation (CV) ≤ 5 %] IR. On average, a sufficient absolute (∅CV = 11.3 %) and relative (∅ICC = 0.67) IR was observed. Without the parameters "missed throws" and "technical errors" in both rounds, the IR increased significantly (∅ICC: from 0.67 to 0.72 & ∅CV from 11.3 to 6.3 %). The heart rate was comparatively more reliable than lactate (∅ICC = 0.71 & ∅CV = 4.23 % vs. ∅ICC = 0.65 & ∅CV = 15.1 %). With respect to load parameters in round one, 50 % (5/10) showed a high IR; in round two, these values decreased to 40 % (4/10). The mean IR of the parameters in round one was higher than in round two (∅ICC = 0.71 & ∅CV = 12.2 % vs. ∅ICC = 0.60 & ∅CV = 14.3 %). Overall, there was an improvement of the athletes in most stress and load parameters from session one to session two. CONCLUSIONS: The HBKT can be attested with a sufficient intraobserver reliability. When the parameters "missed throws" and "technical errors" were excluded, the IR further increased significantly. Therefore, these parameters should be recorded in order to standardized the HBKT, but not be included in the statistical analysis. There are discrete adaptation and learning effects. For this reason, it is essential to familiarise trainers and players with the HBKT test procedure before the first measurement. Otherwise training effects can be easily overrated. Moreover, the test concept of HBKT can be used as a blueprint for the development of sport-specific tests in other team sports (e. g., soccer, basketball). For example, we generated a complex soccer-specific field test 1 based on the HBKT.

[Validity of a complex soccer-specific field test and a non-specific sprint test-assessments for test and match performance]. / Validierung eines komplexen fußballspezifischen und fußballunspezifischen Tests-Leistungsdiagnostik im Spannungsfeld von Test- und Wettkampfleistung.

BACKGROUND: Soccer assessments often lack specificity and complexity. Examinations of validity for soccer assessments, based on the relation between test and match performance, are available although they are scarce. A complex soccer-specific field test which is validated cannot be found in the literature at all. OBJECTIVE: The aim of this follow-up study was to assess the validity of a soccer-specific complexity test (FBKT) and a repeated non-specific sprint test (ST) based on three gold standards: match performance, coach ranking, and league affiliation. MATERIALS AND METHODS: A German fourth league soccer team (n = 14) was assessed using FBKT and ST in the pre-season for the second half of the 2010/2011 season. Afterwards, their performance in 17 matches was evaluated using video analysis in order to compare them with the test parameters (e. g., pass/assist ratio, goals, duelling behaviour). Eighteen months later, the league affiliation of all players was identified and the coach evaluated the tested players. RESULTS: With regard to match performance, playing time was proved to be the most suitable parameter for validating the test performance (FBKT, ST). The total and minimum times of ST were the most powerful parameters in relation to playing time and explained 50 % and 46 % of the variance, respectively. Concerning the FBKT, the parameters "sum of all linear sprints" (24 %) and "total time of all activity series with penalty time in round two" (22 %) explained the highest amount of variance. Coach ranking generated significant odds ratios for the minimum time of ST (OR = 6.5; CI: 3.2 - 5.2 × 1015; p = 0.037), and total time of speed dribbling of the FBKT (OR = 1.3; CI: 1.2 - 199.5; p = 0.036) based on a proportional-odds model. With regard to league affiliation, significant odds ratios occurred with the following parameters: minimum time of ST (OR = 15.8; CI: 2.16 - 115.4; p = 0.007); total time of ST (OR = 3.28; CI: 1.31 - 8.21; p = 0.011); and, total time of speed dribbling for the FBKT (OR = 1.3; CI: 1.01 - 1.61; p = 0.044). CONCLUSIONS: This study showed that the larger logical validity of soccer-specific complex tests does not necessarily translate to a larger construct validity, as compared to non-specific tests. However, their value is not limited to performance evaluation. The FBKT provides valuable information concerning training process control. It is possible that its low validity is caused by the poor performance of the players in soccer-specific consequences of actions (centres, goals) due to the restricted differentiation of players.

[Longitudinal and specific analyses of physical performance in handball]. / Longitudinale, sportartspezifische Leistungsdiagnostik im Handball.

BACKGROUND: Sports-specific, biomechanical measuring stations and measuring-station trainings have become common practice in many forms of sports and are an essential element of the complex assessment of physical performance. In handball, however, there is still considerable research potential in this respect as well as in the systematic generation and acquisition of the requirements profile and progress of strain. OBJECTIVE: The prime objective of the longitudinal study was to determine the potential performance and development of handball players (3 rd league) in general and in terms of handball sport in particular. Another objective was to establish correlations between tests and indicators of performance in competitions. MATERIALS AND METHODS: 13 handball players (age: 26.5 ± 3.6 years) were tested three times (before and after the pre-season preparation phase and at the end of the first half of the season) on two test days each. The examination was composed of sprint test (ST, day 1), handball-specific complex test (HBKT, day 1) and assessment of treadmill diagnostics (LD, day 2). The surveyed parameters were lactate and heart rate (LD/HBKT) as well as time (ST, HBKT) and the number of errors (HBKT). RESULTS: The cardiac (Hfmax = 201 min-1) and metabolic strain (lactate = 17.8 mmol/L) in the HBKT were very high. In the preparatory phase, the average magnitudes of effect registered were at d = 0.31 (ST parameter), d = 0.68 (HBKT parameter) and d = 0.98 (LD parameter). The most significant improvements throughout the entire period of time were registered in the parameters v2 (LD; η2 = 0.371), total goal-throwing time (HBKT; η2 = 0.250), total penalty time (HBKT; η2 = 0.236) and total round 2 (HBKT; η2 = 0.227). In HBKT and LD, the performance level was stabilised by the end of the first half of the season. In terms of speed, however, there was a decline in performance abilities. The competition performance has its highest degree of correlation with cardial (defense: r = -0.656) and metabolic (offensive: r = -0.655) recuperativeness in HBKT. CONCLUSIONS: The findings of this longitudinal survey are on the one hand intended to make assessments of physical performance more efficient (isolated sprint test no longer required) and to improve data output (HBKT: throwing velocity; reference database). In this context, a more extensive consideration of indicators for competition performance and their correlation to specific parameters is recommendable. On the other hand, the applied training contents must be further optimised in terms of their severity and chronology.

[Vestibular disorders. Effects of sensorimotor training on postural regulation and on recovery process]. / Schwindelerkrankungen. Auswirkungen eines sensomotorischen Trainings auf Haltungsregulation und Kompensationsverlauf.

Complex sensorimotor training can improve the postural stability of patients with vestibular neuropathy. Particularly the efficiency of the cerebellar system was significantly improved. In addition, the results show that the affected peripheral vestibular system cannot be influenced directly, regardless of the kind of rehabilitation measure used.

[Development and evaluation of a soccer focused complexity test]. / Entwicklung und Evaluierung eines fußballspezifischen Komplextests.

BACKGROUND: Soccer has increasingly become a technical - tactical (speed of activity!) and athletic sport over the last years. Simultaneously the new training and contest conditions result in new challenges to sports science and sports medicine evaluation. Complex, sports specific field tests for soccer exist rarely and only in low quality. OBJECTIVE: Development and evaluation of a standardised complexity test in soccer (FBKT) for assessment of the complex sports specific and league specific physical performance. MATERIALS AND METHODS: Two regional German soccer teams (Verbandsliga [VL], Oberliga [OL]) (n = 27) were assessed with FBKT. The assessment included lactate levels, heart rate as well as time and error frequency (penalty time per error: 5 s) for defined activity series at defined time points (heart rate: rest, after round 1, prior to round 2, E 0, E 2, E 6, E 10, E 14; lactate: rest, E 2, E 6, E 10, E 14). RESULTS: The heart rate (hr (max) = 200 min (-1)) and metabolic rate (lactate (max) = 17.1 mmol/l) were very excessively high and did only partially differ between the groups (heart rate difference at rest p = 0.005, prior to round 2: p = 0.014, E 6: p = 0.042). Furthermore no significant differences occurred in the following parameters: recovery potential (hr (E0 - E14): p = 0.560; lactate (Max-Min): p = 0.448), technical error (p = 0.384), sprint (p = 0.499), slalom dribbling (p = 0.310), time round 1 (p = 0.119), shots on goal (p = 0.585) and crosses (p = 0.676). Significant difference were only found in the parameters time round 2 (p = 0.004), time round 1 and round 2 (p = 0.013), overall time (running)(time + penalty)(time) (p = 0.022) and speed dribbling (p = 0.005). CONCLUSIONS: Soccer specific complex loads generate very high physical demamds. Although complex, the FBKT proved to be a practical assessment tool with high standardising potential. The FBKT gives plentiful information under competition - like conditions such as technical skills, speed, speed endurance or anaerobe capacity.

[Diagnostic tools for endurance testing in handball players]. / Diagnostik der Ausdauerleistungsfähigkeit im Handball.

BACKGROUND: The physiological demands of handball players on international level has increased during the last years mainly due to rule changes. Therefore a scientific funded training method under sports medical supervision gets more and more important. Nevertheless any only limited data are available concerning adequate tests and methods on endurance and sports related assessment of physical performance in handball. OBJECTIVE: Goal of this experimental cross sectional study was to record the endurance of handball players (regional league) in general and related to their sport. This study was performed in conjunction with the development and testing of a new handball specific complexity test (HBKT) and the use of a new lactate analysis software wesp-analysis during a treadmill test (TT). METHODS: 16 semi-professional handball players (mean age: 27.5 +/- 6.78 years) of a regional team were investigated with TT and HBKT on two different days (time delay 72 h). The parameters lactate, heart rate (TT/HBKT) and the time and rate of faults in the HBKT were recorded. RESULTS: The players showed large deficits in basic endurance capacity. There was a great performance difference within the team, especially in the lower intensity regions (< or = 3 mmol/l). Whereas the maximal heart rate was significantly higher in the TT versus the HBKT (TT: 192 +/- 8.67 min (-1) versus HBKT: 180 +/- 9.23 min (-1); p < 0.001; eta(2) = 0.794). The maximum lactate levels showed directly the opposite (10.1 +/- 2.91 mmol/l for TT versus 12.8 +/- 1.99 mmol/l for HBKT; p < 0.001, eta(2) = 0.644). Maximal run velocity (TT) and general performance (HBKT) was related on a mean level (r = -0.566). CONCLUSIONS: The results show the necessity of individual heart rate dependant basic endurance training. The correlation between the tests is a further sign for the significant importance of endurance capacity for sports performance. A comparison of these results to a higher level handball team would yield further information regarding interpretation and grading of the data. HBKT und lactate analysis software wesp-analysis showed to be practical assessment tools.

[Postural deficits and risk of falling in elderly persons with incipient osteoporosis]. / Posturale Defizite und Sturzrisiko bei älteren Personen mit Verdacht auf Osteoporose.

BACKGROUND: Falls and fall-dependent complications represent major problems in geriatrics. Approximately 80-90% of femoral neck fractures in postmenopausal women are caused by falls. STUDY QUESTION: The goal of this study was to evaluate a new posturographic measurement system (Interactive Balance System, IBS) regarding its potential to predict falls in osteoporotic patients. MATERIALS AND METHODS: A total of 228 patients admitted for osteodensitometry because of suspected osteoporosis were included in the study. During the baseline investigation, bone density and postural regulation were measured. Over a follow-up period of 12 months, all falls were recorded in a fall diary. Participants with more than two falls per year were classified as persons at high risk of falling. RESULTS: In patients with confirmed osteoporosis (n=139), the posturographic frequency range F(2-4) was found to be predictive for falls. The ROC analysis of the dependent fall index FIOR(F2-4) showed an AUC value of 0.88. CONCLUSION: IBS is an effective assessment for fall prediction in osteoporosis. Especially peripheral-vestibular regulation mechanisms seem to be of great importance in the evaluated patient group.

[The impact of different sports on posture regulation]. / Der Einfluss unterschiedlicher Sportarten auf die Haltungsregulation.

BACKGROUND: Previous work has suggested that both the level of activity and the type of sport may have a major impact on postural control. However, no systematic investigation has been performed regarding the various types of professional sports. Particularly, the impact of competitional sports on the postural subsystems has not been elucidated so far. OBJECTIVE: The aim of this study was to investigate the influence of the major professional sport types, such as handball, gymnastics, swimming, and shooting, on the subsystems of postural control. We also tested the hypothesis that specific types of sport have specific effects on postural regulation. METHODS: 155 competitive male and female athletes (handball: n = 30; gymnastics: n = 44; swimming: n = 50; shooting: n = 31), and 34 age- and gender-matched controls were investigated using the Interactive Balance System (IBS; Tetrax Inc., Ramat Gan, Israel). The following spectral and time-domain indices were determined: power in the following frequency bands: P(F1) (0.03 - 0.1 Hz), P(F)(2 - 4) (0.1 - 0.5 Hz), P(F)(5 - 6) (0.5 - 1.0 Hz), P(F)(7 - 8) (> 1.0 Hz), stability index (STABI), and synchronisation index (SYN). RESULTS: Shooting athletes exhibited significantly smaller values of P(F1) (p = 0.003), P(F)(2 - 4) (p < 0.001), and P(F)(7 - 8) (p = 0.002), respectively, than the other athletes investigated. Also, the shooting athletes exhibited the smallest STABI values (p = 0.002). In contrast, the gymnasts showed the largest SYN values (p = 0.002). CONCLUSIONS: Different types of competitive sports exert different effects on the various subsystems of posture control, where especially shooting competitors demonstrate a significantly better posture regulation. Those effects can be parameterised and quantified with the IBS which thus enables an efficient and purposeful training. Furthermore, the IBS is highly suitable for aptitude screening in sports with high posture regulatory demands (shooting competitions, gymnastics, diving etc.).

[Prospective comparison of assessments to evaluate fall risk in a nursing home population]. / Prospektiver Vergleich von Assessments zur Beurteilung der Sturzgefahr bei Pflegeheimbewohnern.

BACKGROUND: Falls represent the main health risk in the over-60 age group. Therefore, evaluation of the individual fall risk and assessment of fall mechanisms are important preventive tools. STUDY QUESTION: The goal of this study was to validate a new posturographic measurement system [Interactive Balance System (IBS)] in terms of fall prediction. MATERIALS AND METHODS: In all, 108 subjects (mean age: 81.9+/-9.5 years) were submitted to the IBS, as well as other fall risk assessment methods [FES-1, Timed-Up-and-Go Test, Performance Oriented Mobility Assessment (Tinetti-Test), Chair-Rising-Test, Tandem stance). The follow-up period of 6 months prospectively recorded all falls using a fall diary. RESULTS: Of the nursing home residents studied, 25 (23%) fell at least once. The posturographic fall index FI(F1&WDI) (sensitivity: 88%) and the Timed-Up-and-Go Test (PPV: 38%) showed the best results regarding sensitivity and positive prediction value (PPV). CONCLUSION: The IBS and the Timed-Up-and-Go Test proved to be the most powerful assessment tools for fall prediction. Furthermore, the IBS is able to provide a purposeful adaption of preventive sensomotoric interventions.

[Impact of therapeutic riding on gait and posture regulation]. / Der Einfluss des Therapeutischen Reitens auf den Gang und die Haltungsregulation.

BACKGROUND: Hippotherapy has become an important therapeutic option in patients suffering from motoric dysfunction. The physiologic basis of this approach is the three-dimensional transmission of the horse's motion onto the patients body. These motion stimuli are believed to exert possitve effects on the patients's postural control systems. AIM: To test the hypothesis that hippotherapy has both positive short- and lang-term effects on gait and posture control of persons suffering from motoric disabilities. METHODS: Twenty-two children and adolescents aged 9.69 +/- 4.01 years (range: 9.69 +/- 4.01 years) with motoric dysfunctions were included in a prospective matched control study. In each participant, gait and posture control were investigated on four different occasions (O1 - O4) using the Interactive balance system (IBS; Tetrax Inc., Ramat Gan, Israel) and the portable gait analysis sytem RehaWatch (Hasomed, Magdeburg, Germany). The dates of gait and posture analysis were defined as follows: O 1: immediately prior to first therapeutic riding session (TRS); O 2: immediately after first TRS; O 3: after the last day of an eight weeks period of daily TRS; O 4: seven weeks later after a TRS free interval. RESULTS: The following parameters were slightly improved (adjusted significance level of p < 0.003) after eight weeks of therapeutic riding: (O1 vs. O 3): (1) walking distance (p = 0.009, eta(2) = 0.339); (2) pace frequency (p = 0.007, eta(2) = 0.358); (3) walking speed (p = 0.006, eta(2) = 0.367), and (4) time of attachment (p = 0.007, eta(2) = 0.360). The only short-term effect observed was a significant decrease of the attachment phase (p = 0.002, eta(2) = 0.387). Interestingly, gait symmetry remained unaffected. Posturography (adjusted significance level of p < 0.01) at O 1 versus O 2 (short-term) showed a significant decrease of the performance of both the visual-nigrostriatal subsystem (p < 0.001) and the somato-sensory subsystem (p = 0.001). At O 1 versus O 3 (long-term), the following parameters were sharply decreased: (1) postural stability (p = 0.011), and (2) somatosensory performance (p = 0.011). CONCLUSIONS: In the individuals investigated, an eight weeks series of therapeutic riding did not improve posture control and had only a small positive effect on gait performance. The reasons for these rather disappointing results could have been the low number of therapeutic riding sessions (0.5 sessions per week), and the relatively short duration (30 min) of each session. It remains to be seen, whether a higher density and longer duration of therapeutic riding sessions yields better results.

[Autonomic dysfunction and beta-adrenergic blockers in multiple organ dysfunction syndrome]. / Autonome Dysfunktion und Betablocker beim Multiorgandysfunktionssyndrom.

BACKGROUND AND OBJECTIVE: The multiple organ dysfunction syndrome (MODS), a failure of two or more organ systems, is the endstage of initial trigger events in diseases such as acute coronary syndrome or sepsis. The mortality is high (40 - 60 %). The present study aimed to detect whether beta-adrenergic blockers (BAB) which may affect sympathetic-parasympathetic balance have a positive influence on outcome. METHODS: Data on 157 patients with MODS (83 male, 74 female, mean age 61.3 +/- 13.4 years) were retrospectively analysed concerning BAB medication and autonomic dysfunction. A 24-hour-Holter-ECG which had been applied within the initial 48 hours of illness was analysed for heart rate variability (HRV). All patients were followed to determine 28-day mortality. RESULTS: 69 of the 157 MODS patients had received BAB. This treatment was associated with a higher survival probability (hazard ratio [HR] 0.4, 95 % confidence interval [CI] 0.23 - 0.68; p = 0.001). Survival benefit was especially seen in the subgroup of MODS patients who had an ischemically triggered MODS (HR 0.2 [0.1 - 0.5], p = 0.001). HRV was less reduced in the BAB group compared to patients without this medication. CONCLUSION: MODS patients treated with beta-adrenercic blockers may have a survival benefit which is especially seen in the subgroup of MODS patients with ischemically triggered MODS. Moreover, BAB medication is associated with a less pronounced autonomic dysfunction in MODS (especially the vagal modulation of heart rate) which might result in a lower inflammatory response. Hence, future prospective studies have to show the relevance of beta-adrenergic blockers in MODS.

[Specific riding styles are associated with specific effects on bodily posture control]. / Einfluss unterschiedlicher Reitdisziplinen auf die Haltungsregulation.

BACKGROUND: The assessment of body posture control can be time consuming and cumbersome due to the complexity and the multimodal influence of a multiply influenced system. Various types of equine paces, such as stepping, trotting or galloping, result in acceleration and deceleration forces of different magnitude. These forces induce, in the horseman, reflexes that mediate motor activity to sustain posture balance and counterbalance the gravitational pull. However, there is a paucity of real life data regarding the extent of the various postural subsystems that are recruited to control postural balance in specific equine disciplines, such as classical dressage, show jumping, or vaulting. This study was conducted to bridge that gap. AIM OF THE STUDY: The aim of this explorative study was to identify the types of the postural subsystems involved in balance control and assess the magnitude of their activities during classical dressage, show jumping, vaulting, and versatility riding. METHODS: 144 horseback riders (8.1 % males) aged 17.3 +/- 2.9 years and 38 age matched controls (non riders) were investigated. The riders studied were competing in dressage, show jumping, vaulting, and versatility. In each individual, postural control was investigated by means of the "interactive balance system (IBS)" that enabled us to determine the spectral power in the following four standard frequency bands: F 1 (0.03 - 0.1 Hz), F 2 - 4 (0.1 - 0.5 Hz), F 5 - 6 (0.5 - 1.0 Hz), and F 7 - 8 (1.0 - 3.0 Hz). In addition, three motorical output indices were calculated: heel-to-toe-ratio (HTR), synchronization of feet (SYNC), and the global stability index of postural balance (STAB). Furthermore, each individual was interviewed regarding riding time, frequency and discipline and also about other sports activities and disorders of health. RESULTS: The mean training period of the horseback riders was 122 +/- 45.8 months, and mean weekly frequency of training was 5.5 +/- 1.8 days per week. Balance control was most effective in dressage and vaulting riders and least effective in show jumping competitors: HTR was 51 +/- 8 % (dressage), 48 +/- 8 % (show jumping), 47 +/- 8 % (versatility), 51 +/- 7 % (vaulting); SYNC was 523 +/- 124a. i. (dressage), 497 +/- 156a. i. (show jumping), 468 +/- 155a. i. (versatility), 589 +/- 126a. i. (vaulting). Spectral analysis revealed significantly higher power in F 1, F 2 - 4, and F 7 - 8 in dressage competition than in the other equestrian disciplines but not compared with the controls. Significantly differences between riders versus non riders were only found in HTR (p = 0.045) und SYNC (p = 0.009). CONCLUSIONS: Balance control was most effective in dressage and vaulting riders and least effective in the show jumping competitors. Thus, except for dressage and vaulting, our results do not suggest a positive effect of traditional riding styles on postural stability and control.