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PubMed1996

[Standardized examination of the elbow].

The elbow joint often reacts to different injury patterns of the intra- and extra-articular structures with uniform symptoms that can hardly be differentiated. Furthermore, several neural entrapment syndromes around the elbow should be taken into consideration, because they make the differential diagnosis even more difficult. Cervical nerve root and brachial plexus irritations can also be responsible for pain, which is subjectively transferred to the elbow. The purpose of the study was to improve the etiological differentiation by introducing a new standardized physical examination program. Besides the static and dynamic examination and specific stability tests, the symptoms of relevant neural compression syndromes are checked. This physical examination program represents a guideline for the systematic evaluation of the anatomical and morphological structures that are responsible for the individual symptoms.

Arm Injuries↗
PubMed1992

Optimization of cervical cancer screening.

The aim of this study was to investigate how a screening program interacts with the dynamic natural history of cervical neoplasia in order to learn how screening for cervical cancer should be carried out most cost-effectively. For the purpose of optimization, the fundamental quantities of the natural history are the shape of the curve of age-specific prevalence rates of cancer in situ, and the duration of this stage before progression to invasive cancer. Since these quantities seem similar in different populations, the results probably can be generalized. Simulation studies revealed that optimal screening implies a nonperiodic schedule, and that this schedule is dependent not only on the number of screenings, but also on the efficiency of the screening rounds. With lower efficiency, the schedule should be concentrated into a shorter period. The effect of screening is also especially sensitive to the choice of age at the first and--to a smaller extent--last screening. The results concerning three different objectives also were compared, namely reduction of the cumulative number of invasive cancers, reduction of deaths due to cervical cancer, and reduction of years-of-life lost. The choice of objective also plays a role in the design of an optimal screening program. The theoretical approach in this analysis easily can be developed and accommodated to more complex individual situations such as prior screening histories and differing screening schedules in high- and low-risk women.

Adult↗
PubMed1992

Surprising success in Kenya's FP programme.

Mrs. Margaret Gachara, Deputy Director of the Ministry's Family Health Division, explained that the strengths and weaknesses of the program have recently been examined using a new operations research approach, known as situation analysis. "If family planning was not working in Kenya, we had to know why in order to decide what to do about it. We began the study to find out where our weaknesses lay. To our surprise, we found that we were not weak, but moderately successful," she said. The Kenya Situation Analysis Study, conducted by the Health Ministry and the Population Council, revealed that contraceptive prevalence increased by 2%/year between 1984-89, from 17% to 27%. "That is quite acceptable by World Bank and WHO standards. Our total fertility rate has dropped from 7.9% to 6.7%, and in urban areas is down to 3.8%. We are now continuing with in-depth studies, but we expect to be able to say next year that our family planning program should have a moderately high rating, especially in terms of quality of care." Since the 1st results of the Analysis Study were published, family planning agencies in several other African, Asian and Latin American countries have requested similar studies. The Kenyan study showed that the Pill is the most popular method of contraception, used by about 80% of family planning acceptors. However, the use of injectable contraceptives has risen about 4-fold in recent years, from 0.5 to 1.8 million doses a year, Mrs. Gachara said. When the study was conducted, availability of injectable contraceptives was very poor and did not have strong logistical support. This has now been changed, and its use is going up very fast in rural areas. 1 of the reasons is that women who want to use contraception, but do not have support from their husbands, can have injection without their husbands knowing. Although the 3 monthly injectable initially had a very bad press and little Parliamentary support, research has shown that many of the fears were unfounded. Kenyan policy is to make the injectable available to women with 4 children and to those over 35. Guidelines have recently been changed, to require 1 live birth before injectables are offered, rather than 2. The government is also making efforts to promote the use of Noristerat, and a pilot program is currently underway to study implants. The situation analysis did reveal problems in a number of areas, and a list of recommendations has now been drawn up to improve the quality of care. The recommendations include improved supply of information on permanent contraceptive methods and on the side-effects of other contraceptives, a reduction in waiting times for family planning services and an increase in follow-up. "The future looks good for family planning in Kenya, but we have to match our services to contraceptive health benefits and to focus more on maternal health in its totality," Mrs. Gachara said.

Africa↗
PubMed2001

Biomechanical evidence supporting a differential response to acute ACL injury.

OBJECTIVE: To describe movement patterns in people with complete anterior cruciate ligament rupture objectively identified as good candidates for non-operative management of the injury. DESIGN: Involved side kinematics and kinetics were compared to the uninvolved side and to uninjured subjects. BACKGROUND: High-level athletes with anterior cruciate ligament rupture and poor dynamic stability (non-copers) have movement alterations, including less knee flexion and a decreased internal knee extensor moment during loading response, that are not seen in those with excellent knee stability (copers). Our screening exam can identify people with good rehabilitation potential for non-operative management of anterior cruciate ligament injury (potential copers), but the movement strategies of these individuals are unknown. METHODS: Sagittal plane kinematics and kinetics during the stance phase of walking and jogging were collected from 11 subjects who had an acute anterior cruciate ligament rupture and met the criteria of the screening exam, and were compared to 10 uninjured subjects, who we studied previously. Variables were those in which non-copers differed from uninjured subjects. RESULTS: The potential copers flexed their involved knee less than uninjured subjects and their uninvolved side during walking. Potential copers, compared to uninjured subjects, also had a lower vertical ground reaction force during loading response, a lower knee support moment, and an increased ankle support moment during walking. In jogging, the involved knee angle at initial contact was more extended compared to uninjured subjects, and the amount of knee flexion was less than the uninvolved side. No differences in kinetics were present during jogging. CONCLUSIONS: This study provides evidence that the potential copers identified by the screening examination have movement patterns that are consistent with people who have more knee stability than non-copers. RELEVANCE: Although potential copers have developed some characteristics of a successful stabilization strategy, the presence of kinematic alterations indicates that they may benefit from training programs designed to enhance dynamic knee stability.

Activities of Daily Living↗
PubMed2003

Muscle fatigue and fatigue-related biomechanical changes during a cyclic lifting task.

STUDY DESIGN: Electromyographic and biomechanical methods were utilized to investigate correlations between indexes of localized muscle fatigue and changes in the kinematics and kinetics of motion during a cyclic lifting task. SUMMARY OF BACKGROUND DATA: Recent advances in time-frequency analysis procedures for electromyographicic signal processing provide a new way of studying localized muscle fatigue during dynamic contractions. These methods provide a means to investigate fatigue-related functional impairments in patients with low back pain. OBJECTIVES: To study the relationship between localized muscle fatigue and the biomechanics of lifting and lowering a weighted box. Fatigue-related changes in the electromyographicic signal of trunk and limb muscles were evaluated and compared to kinematic and kinetic measures in order to determine whether lifting strategy is modified with fatigue. METHODS: A total of 14 healthy male subjects (26 +/- 5 years) cyclically lifted and lowered a 13 kg box (12 lifts/min) for 4.5 minutes. A 5-second static maximum lifting task was included immediately before and after the cyclic lifting task to measure changes in lifting strength and static electromyographicic fatigue indexes. Electromyographic signals from 14 muscle sites (including paravertebral and limb muscles) were measured. Changes in the electromyographicic Instantaneous Median Frequency, a fatigue index, were computed using time-frequency analysis methods. This index was compared with more standardized measures of fatigue, such as those based on electromyographicic median frequency acquired during a static trunk extension test, subjective fatigue measures, and maximal static lifting strength. Biomechanical measures were gathered using a motion analysis system to study kinematic and kinetic changes during the lifting task. RESULTS: During the cyclic lifting task, the electromyographic Instantaneous Median Frequency significantly decreased over time in the paravertebral muscles, but not in the limb muscles. Paravertebral electromyographicic Instantaneous Median Frequency changes were consistent with self-reports of fatigue as well as decreases in trunk extension strength. The magnitude of muscle-specific changes in electromyographicic Instantaneous Median Frequency was not significantly correlated with electromyographicic median frequency changes from the static trunk extension task. The load of the box relative to the maximal static lifting strength significantly affected the electromyographicic Instantaneous Median Frequency changes of paravertebral back muscles. Significant changes with fatigue during the task were found in the angular displacements at the knee, hip, trunk, and elbow. These biomechanical changes were associated with increased peak torque and forces at the L4-L5 vertebral segment. CONCLUSIONS: Our results demonstrate correlation between localized muscle fatigue and biomechanical adaptations that occur during a cyclic lifting task. This new technique may provide researchers and clinicians with a means to investigate fatigue-related effects of repetitive work tasks or assessment procedures that might be useful in improving education, lifting ergonomy, and back school programs. Although both the dynamic and static tasks resulted in spectral shifts in the electromyographicic data, the fact that these methods led to different muscle-specific findings indicates that they should not be considered as equivalent assessment procedures.

Adult↗
PubMed1999

Ageing of population and health care expenditure: a red herring?

This paper studies the relationship between health care expenditure (HCE) and age, using longitudinal rather than cross-sectional data. The econometric analysis of HCE in the last eight quarters of life of individuals who died during the period 1983-1992 indicates that HCE depends on remaining lifetime but not on calendar age, at least beyond 65+. The positive relationship between age and HCE observed in cross-sectional data may be caused by the simple fact that at age 80, for example, there are many more individuals living in their last 2 years than at age 65. The limited impact of age on HCE suggests that population ageing may contribute much less to future growth of the health care sector than claimed by most observers.

Aged↗
PubMed1997

Fourfold Clusters of Rovibrational Energies in H2Po Studied with an ab Initio Potential Energy Function

We report here an ab initio investigation of the cluster effect (i.e., the formation of four-member groups of nearly degenerate rotation-vibration energy levels at higher J and Ka values) in the H2Po molecule. The potential energy function has been calculated ab initio for a total of 143 molecular geometries by means of the CCSD(T) method, using an averaged relativistic effective potential for Po in conjunction with a newly optimized basis set. The values of the potential energy function obtained cover the region up to around 5000 cm-1 above the equilibrium energy. On the basis of the ab initio potential, the rotation-vibration energies of H2209Po have been calculated with the MORBID (Morse oscillator rigid bender internal dynamics) Hamiltonian and computer program. In particular, we have calculated the rotational energy manifolds for J </= 40 in the vibrational ground state. We find that the formation of fourfold clusters in H2Po is very similar to that in H2Te. Copyright 1997 Academic Press. Copyright 1997Academic Press

Journal Article↗
PubMed1983

Alterations of mechanical characteristics of human skeletal muscle during strength training.

To investigate the influence of strength training on the mechanical characteristics of human skeletal muscle, 14 male subjects went through training of combined heavy concentric and eccentric contractions three times a week for 16 weeks. The strength training program consisted mainly of dynamic exercises for leg extensors with loads of 80 to 120% of one maximum repetition. The force-time curves produced during various vertical jumps were the basis for calculation of various mechanical parameters. In addition to a great increase (p less than 0.001) in maximal isometric force, heavy resistance strength training also caused significant (p less than 0.05-0.01) increases in heights and in various mechanical parameters in positive work phases of vertical and drop jumps. The increase in positive force during a fast dynamic contraction was correlated (p less than 0.01) with the reduced time to produce a certain submaximal force level in isometric condition. No changes in the elastic properties of the muscle were observed as judged from the difference between the counter-movement and squat jumps. When the training was followed by the 8-week detraining period a great decrease (p less than 0.001) in maximal force took place, but only minor changes (ns) were observed in fast force production.

Adult↗
PubMed1991

Direct NOE refinement of biomolecular structures using 2D NMR data.

A set of computer programs called DINOSAUR has been developed, which allows the refinement of biomolecular structures directly from 2D NOE intensities. The NOE restraining potential implemented emphasises the weak intensities corresponding to larger distances which are more likely to determine the three-dimensional structure. An approximation based on a two-spin approximation is proposed for the gradient of the NOE intensities instead of the exact solution which is extremely time-consuming. The DINOSAUR routines have been implemented in various refinement programs (Distance bound Driven Dynamics, Molecular Dynamics and Energy Minimisation) and tested on an eight-residue model peptide.

Magnetic Resonance Spectroscopy↗
PubMed1987

Increased trabecular bone density due to bone-loading exercises in postmenopausal osteoporotic women.

A program of diverse and dynamic loading exercises of the distal forearm, a common site of osteoporotic fractures, was applied three times a week for 5 months to 14 postmenopausal osteoporotic women. Two parameters were used to assess the effect of the exercises on bone mass. The mass density of bone (g/cm3) was measured by the Compton scattering technique. The bone mineral content (g/cm2) was measured by single photon absorptiometry. Both measurements were taken at the same location in the distal radius 1 year prior to the exercise period, at its beginning, and at its end, in both the exercised group and a matched control group of 26 osteoporotic women. During the exercise period the mean bone density decreased by 1.9% in the control group whereas it increased by 3.8% in the exercise group. The bone mineral content results did not demonstrate any significant trend over the whole period of the study. It is concluded that the trabecular bone tissue in the distal radius of postmenopausal osteoporotic women responds favorably to dynamic and diverse bone stressing exercises even in the seventh decade of life.

Adipose Tissue↗
PubMed2005

[Longitudinal data related to health. A survey of health related panel studies in Germany].

Individual longitudinal data are indispensable for studying the differential incidence of diseases and of possible chronic conditions, health care interventions and outcomes in the course of time, the effects of changing population structure on morbidity, the demand and use of health services, as well as the efficacy and efficiency of health care guidelines. Here, we present an up to date survey of panel studies in Germany, in so far as these are either still active or were completed only recently, and in so far as they are accessible via public use files or equivalent solutions for the scientific community. There are some health related items on existing general purpose national panel studies, but no health related representative national panel study. In addition to the well known unique potential of panel data, we demonstrate, for special populations (e. g. foreigners and people living in institutionalised settings), as well as for special items (salutogenetic potentials and preventive resources), the particular need for health related panel data in the German context.

Data Collection↗
PubMed2000

Extent of compensation for variations in monkey saccadic eye movements.

We investigated and quantified the ability of the primate saccadic system to generate accurate eye movements in spite of naturally occurring variations in saccadic speed and trajectory. We show that the amplitude of a series of saccades directed to the same target is positively correlated to their peak speed, i.e., the faster the saccade, the bigger its amplitude. We demonstrate that this result cannot be simply accounted for by the main sequence, and that on average the saccadic system is able to compensate for only 61% of the variability in speed. Deviations from the average trajectory are also only partially compensated: the underlying mechanism, which tends to bring the eyes back toward the desired trajectory, underperforms for small movements and overperforms for large movements. We also demonstrate that the performance of this compensatory mechanism, and the metrics of saccades in general, do not depend on the presence of visual information during the movement. By showing that deviations from the desired behavior are corrected during the saccade, our results further support the hypothesis that the innervation signal that generates saccadic eye movements is not pre-programmed but rather is dynamically adjusted during the movement. However, the compensation for deviations from the desired behavior is only partial, and the underlying mechanisms have yet to be completely understood. Although none of the current models of the saccadic system can account for our results, some of them, if appropriately modified, probably could.

Adaptation, Physiological↗
PubMed2002

[Resource allocation and justice in distribution of services in medical management of elderly patients].

This paper presents the most important arguments in medical allocation based on an analysis of the relevant literature. The main arguments of rationing scarce medical resources are scrutinized. Especially the use of age limit considerations are critically reviewed. The discussion takes place against a backdrop of aggravating pressure on old people as cost factors. As a basis for further discussion, the authors give a brief history of theories of justice in philosophy. Finally minimum requirements for a constructive and responsible discussion are stated.

Aged↗
PubMed2002

[Managing patients with dementia--current status and formulating dementia policy desiderata and options ].

The demographic and epidemiological scenarios, concerning persons with dementia, are in tension between the legal general conditions of care, on the one hand, and the conceptual alignment, on the other hand; this tension is hardly resolved by the momentary activities in health and care policy. Even on the level of assessment, there are scarcely any instruments to picture the specific needs of patients with dementia. Concepts of supply for persons with dementia are widely still divided by the differentiation between stationary and outpatient. Intelligent mixtures and paradigmatic reorientation towards normalization or split responsibility have not yet enfolded their embossing effects in practice. The care of persons with dementia is in many respects still bound in pre-technical constellations: this applies to the conceptual bias inside an institution or service of old people's care, to legal and economical general conditions and instruments of control and in many ways also to the technical discourse. The relevancy of attendance of people with dementia today and in the future justifies talking about "dementia policy". Options for dementia policy lay in a consequent adaptation of the theory of the New Welfare Mix, which was developed by the political sciences, including discussion about normalization in the area of help for disabled people and in the reformulation of competence between the means of fringe benefits and employees' benefits in joint responsibility.

Aged↗
PubMed2002

[Promoting competition and improving quality. Accepting the intergenerational contract by stabilizing health care reform].

The challenge of demographic transition requires a health care reform which strengthens competition and quality in health care. With this, important contributions in stabilizing intergenerational relations, especially intergenerational solidarity in the public health care system, can be achieved. The reform proposal by an expert group, invited by the Friedrich-Ebert-Foundation to develop a concept of health care reform, takes these considerations into account.

Aged↗
PubMed2003

[Increasing life expectancy--the big social issue of the 21st century?].

Due to the combined effects of a persistent low birth rate, the forthcoming retirement of the "baby-boom generation" and an increasing life expectancy, the German system of "social security" will face severe challenges in the coming decades. The foreseeable doubling of the ratio between pensioners and employees by 2050 would cause a strong increase in social security contributions and taxes for the "pay-as-you-go"-financed pension system. In addition, the expected tripling of highly aged people would increase the public expenditures for health care and nursing care of elder people, which also have to be financed by the future working generations. In order to lessen the increasing burden on future generations, social reforms are necessary soon. If these are not performed, the distributional conflict between young and old people could become worse over the forthcoming decades.

Aged↗