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URPOSE: Today, the majority of medical graduates in countries such as the UK, the US or Germany are female. This poses a major problem for workforce planning especially in urology. We here use first the first time the previously established Brüggmann Groneberg (BG) index to assess if female academic career options advance in urology.
METHODS: Different operating parameters (student population, urology specialist population, urology chair female:male (f:m) ratio) were collected from the Federal Office of Statistics, the Federal Chamber of Physicians and the medical faculties of 36 German universities. Four time points were monitored (2000, 2005, 2010 and 2015). From these data, female to male (f:m) ratios and the recently established career advancement (BG) index have been calculated.
RESULTS: The German hospital urology specialists' f:m ratios were 0.257 (499 female vs. 1944 male) for 2015, 0.195 for 2010, 0.133 for 2005 and 0.12 for 2000. The career advancement (BG) index was 0.0007 for 2000, 0,0005 for 2005, 0.094 for 2010 and 0.073 for 2015. The decrease from 2010 to 2015 was due to an increase in the f:m ratio of hospital urologists and female medical students.
CONCLUSION: The BG index clearly illustrated that there is an urgent need for special academic career funding programs to counteract gender problems in urology. The BG index has been shown to be an excellent tool to assess female academic career options and will be very helpful to assess and document positive or negative changes in the next decades.
Background: Immigration has a strong impact on the development of health systems, medicine and science worldwide. Therefore, this article provides a descriptive study on the overall research output.
Methods: Utilizing the scientific database Web of Science, data research was performed. The gathered bibliometric data was analyzed using the established platform NewQIS, a benchmarking system to visualize research quantity and quality indices.
Findings: Between 1900 and 2016 a total of 6763 articles on immigration were retrieved and analyzed. 86 different countries participated in the publications. Quantitatively the United States followed by Canada and Spain were prominent regarding the article numbers. On comparing by additionally taking the population size into account, Israel followed by Sweden and Norway showed the highest performance. The main releasing journals are the Public Health Reports, the Journal of Immigrant and Minority Health and Social Science & Medicine. Over the decades, an increasing number of Public, Environmental & Occupational Health articles can be recognized which finally forms the mainly used subject area.
Conclusion: Considerably increasing scientific work on immigration cannot only be explained by the general increase of scientific work but is also owed to the latest development with increased mobility, worldwide crises and the need of flight and migration. Especially countries with a good economic situation are highly affected by immigrants and prominent in their publication output on immigration, since the countries’ publication effort is connected with the appointed expenditures for research and development. Remarkable numbers of immigrants throughout Europe compel medical professionals to consider neglected diseases, requires the public health system to restructure itself and finally promotes science.
Objectives: Inadequate oral hygiene still leads to many serious diseases all over the world. Therefore, this study aimed to analyze scientific research in the field of oral health in order to be able to comprehend their relevant subject areas, research connections, or developments. Methods: This study aimed to assess the global publication output on oral hygiene to create a world map that provides background information on key players, trends, and incentives of research. For this purpose, established bibliometric parameters were combined with state-of-the-art visualization techniques. Results: This study shows the actual key players of research on oral hygiene in high-income economies with only marginal participation from lower economies. This still corresponds to the current burden situations, but they are more and more shifting to the disadvantage of the low-income countries. There is a clear North–South and West–East gradient, with the USA and the Western European nations being the most publishing nations on oral hygiene. As an emerging country, Brazil plays a role in the research. Conclusions: The scientific power players were concentrated in high-income countries. However, the changing epidemiological situation requires a different scientific approach to oral hygiene. This requires an expansion of the international network to meet the demands of future global oral health burdens, which are mainly related to oral hygiene.
Objective: Worldwide, the respiratory syncytial virus (RSV) represents the predominant viral agent causing bronchiolitis and pneumonia in children. To conduct research and tackle existing healthcare disparities, RSV-related research activities around the globe need to be described. Hence, we assessed the associated scientific output (represented by research articles) by geographical, chronological and socioeconomic criteria and analysed the authors publishing in the field by gender. Also, the 15 most cited articles and the most prolific journals were identified for RSV research.
Design: Retrospective, descriptive study.
Setting: The NewQIS (New Quality and Quantity Indices in Science) platform was employed to identify RSV-related articles published in the Web of Science until 2013. We performed a numerical analysis of all articles, and examined citation-based aspects (eg, citation rates); results were visualised by density equalising mapping tools.
Results: We identified 4600 RSV-related articles. The USA led the field; US-American authors published 2139 articles (46.5%% of all identified articles), which have been cited 83 000 times. When output was related to socioeconomic benchmarks such as gross domestic product or Research and Development expenditures, Guinea-Bissau, The Gambia and Chile were ranked in leading positions. A total of 614 articles on RSV (13.34% of all articles) were attributed to scientific collaborations. These were primarily established between high-income countries. The gender analysis indicated that male scientists dominated in all countries except Brazil.
Conclusions: The majority of RSV-related research articles originated from high-income countries whereas developing nations showed only minimal publication productivity and were barely part of any collaborative networks. Hence, research capacity in these nations should be increased in order to assist in addressing inequities in resource allocation and the clinical burden of RSV in these countries.
Introduction: Curare is one of the best-examined neurotoxins of the world, which has empirically been used for centuries by American Indigenes. Research on curare has been performed much later, a global scientometric analysis on curare research or its derivates does not yet exist. This bibliometric analysis is part of the global NewQis-project and should illuminate both toxic and historic issues of research on curare.
Methods: The ISI Web of Science was searched for data covering 1900 to 2013 using a term which included as many original articles on curare as possible. 3,867 articles were found and analyzed for common bibliometric items such as the number of citations, language of the articles or the (modified) Hirsch-Index (h-index). Results are illustrated utilizing modern density equalizing map projections (DEMP) or beam diagrams.
Results: Most publications were located in North America and Europe. The USA has the highest number of publications as well as the highest h-index. The number of publications overall rose until the late 1990s and later decreased. Furthermore, sudden increases of research activity are ascribable to historic events, like the first use of curare as muscle relaxant during surgery.
Discussion: This scientometric analysis of curare research reflects several tendencies as previously seen in other bibliometric investigations, i.e. the scientific quality standard of North America and Europe. Research on curare decreased however, due to the declining attention towards this muscle relaxant. This work exemplifies also how scientometric methods can be used to illuminate historic circumstances immediately stimulating scientific research.
Fit to play : posture and seating position analysis with professional musicians - a study protocol
(2017)
Background: Musical performance-associated musculoskeletal disorders (MSD) are a common health problem among professional musicians. Considering the manifold consequences arising for the musicians, they can be seen as a threat for their professional activity. String players are the most affected group of musicians in this matter. Faults in upper body posture while playing the instrument, causing un-ergonomic static strain on the back and unergonomic limp-movements, are a main reason for musculoskeletal disorders and pain syndromes.
Methods: A total of 66 professional musicians, divided into three groups, are measured.
The division is performed by average duration of performance, intensity of daily exercise and professional experience. Video raster stereography, a three-dimensional analysis of the body posture, is used to analyse the instrument-specific posture. Furthermore the pressure distribution during seating is analysed. Measurements are performed because the musician is sitting on varying music chairs differing in structure and/or construction of the seating surface. The measurements take place in habitual seating position as well as during playing the instrument.
Results: To analyse the influence of different chairs, ANOVA for repeated measurements or Friedman-test is used, depending on normality assumptions. Comparison of posture between amateur musicians, students, and professional orchestral musicians is carried out the non-parametric Jonckheere-Terpstra-test.
Conclusions: Our method attempts to give the musicians indications for the right music chair choice by analyzing the chair concepts, so that thereby preemptively MSD can be reduced or prevented.
Background: Dental professionals are subjected to higher risks for musculoskeletal disorders (MSDs) than other professional groups, especially the hand region. This study aims to investigate the prevalence of hand complaints among dentists (Ds) and dental assistants (DAs) and examines applied therapies. Methods: For this purpose, an online questionnaire analysed 389 Ds (240female/149male) and 406 DAs (401female/5male) working in Germany. The self-reported data of the two occupational groups were compared with regard to the topics examined. The questionnaire was based on the Nordic Questionnaire (self-reported lifetime, 12-month and 7-day MSDs prevalence of the hand, the conducted therapy and its success), additional occupational and sociodemographic questions as well as questions about specific medical conditions. Results: 30.8% of Ds affirmed MSDs in the hand at any time in their lives, 20.3% in the last twelve months and 9.5% in the last seven days. Among DAs, 42.6% reported a prevalence of MSDs in the hand at any time in their lives, 31.8% in the last 12 months and 15.3% in the last seven days. 37.5% of the Ds and 28.3% of the DAs stated that they had certain treatments. For both, Ds and DAs, physiotherapy was the most frequently chosen form of therapy. 89.7% of Ds and 63.3% of DAs who received therapy reported an improvement of MSDs. Conclusion: Although the prevalence of MSDs on the hand is higher among DAs than among Ds, the use of therapeutic options and the success of therapy is lower for DAs compared to Ds.
Traditional ergonomic risk assessment tools such as the Rapid Upper Limb Assessment (RULA) are often not sensitive enough to evaluate well-optimized work routines. An implementation of kinematic data captured by inertial sensors is applied to compare two work routines in dentistry. The surgical dental treatment was performed in two different conditions, which were recorded by means of inertial sensors (Xsens MVN Link). For this purpose, 15 (12 males/3 females) oral and maxillofacial surgeons took part in the study. Data were post processed with costume written MATLAB® routines, including a full implementation of RULA (slightly adjusted to dentistry). For an in-depth comparison, five newly introduced levels of complexity of the RULA analysis were applied, i.e., from lowest complexity to highest: (1) RULA score, (2) relative RULA score distribution, (3) RULA steps score, (4) relative RULA steps score occurrence, and (5) relative angle distribution. With increasing complexity, the number of variables times (the number of resolvable units per variable) increased. In our example, only significant differences between the treatment concepts were observed at levels that are more complex: the relative RULA step score occurrence and the relative angle distribution (level 4 + 5). With the presented approach, an objective and detailed ergonomic analysis is possible. The data-driven approach adds significant additional context to the RULA score evaluation. The presented method captures data, evaluates the full task cycle, and allows different levels of analysis. These points are a clear benefit to a standard, manual assessment of one main body position during a working task.
The aim of this study was to determine association between constitutional, medical history and axiographic parameters with postural control parameters. Overall, 106 healthy female subjects aged between 21 and 30 years were measured. Data collection was carried out by completing a questionnaire on constitutional parameters, illnesses, accidents and medical/orthodontic therapies, as well as by axio- and posturographic measurements. Data were analyzed using correlations, pair comparisons and group comparisons. The significance level was set at p ≤ 0.05. The statistical evaluation showed significant correlations between sporting exercise and body sway in the sagittal direction (p ≤ 0.03), the BMI and the load on the forefoot/rear foot (p ≤ 0.01), the mouth opening and the load on the forefoot/rearfoot (p ≤ 0.01) and the presence of a deviation with the load on the left/right foot (p ≤ 0.01). The physical condition as well as the temporo-mandibular system are associated with the postural control in young women. Therefore, a holistic diagnosis and therapy will be supported by the present outcomes.
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.
Background; Musculoskeletal disorders (MSD) are a common health problem among dentists. Dental treatment is mainly performed in a sitting position. The aim of the study was to quantify the effect of different ergonomic chairs on the sitting position. In addition, it was tested if the sitting position of experienced workers is different from a non-dental group.
Methods; A total of 59 (28 m/31f) subjects, divided into two dentist groups according to their work experience (students and dentists (9 m/11f) < 10 years, dentists (9 m/10f) ≥ 10 years) and a control group (10 m/10f) were measured. A three-dimensional back scanner captured the bare back of all subjects sitting on six dentist’s chairs of different design. Initially, inter-group comparisons per chair, firstly in the habitual and secondly in the working postures, were carried out. Furthermore, inter-chair comparison was conducted for the habitual as well as for the working postures of all subjects and for each group. Finally, a comparison between the habitual sitting posture and the working posture for each respective chair (intra-chair comparison) was conducted (for all subjects and for each group). In addition, a subjective assessment of each chair was made.
For the statistical analysis, non-parametric tests were conducted and the level of significance was set at 5%.
Results: When comparing the three subject groups, all chairs caused a more pronounced spinal kyphosis in experienced dentists. In both conditions (habitual and working postures), a symmetrical sitting position was assumed on each chair.
The inter-chair comparisons showed no differences regarding the ergonomic design of the chairs. The significances found in the inter-chair comparisons were all within the measurementerror and could, therefore, be classified as clinically irrelevant.
The intra-chair comparison (habitual sitting position vs. working sitting position) illustrated position-related changes in the sagittal, but not in the transverse, plane. These changes were only position-related (forward leaned working posture) and were not influenced by the ergonomic sitting design of the respective chair. There are no differences between the groups in the subjective assessment of each chair.
Conclusions; Regardless of the group or the dental experience, the ergonomic design of the dentist’s chair had only a marginal influence on the upper body posture in both the habitual and working sitting postures. Consequently, the focus of the dentist’s chair, in order to minimize MSD, should concentrate on adopting a symmetrical sitting posture rather than on its ergonomic design.
Kinematic analysis of work-related musculoskeletal loading of trunk among dentists in Germany
(2017)
BACKGROUND: In Germany, about 86.7 % of the dentists have stated to suffer from pain in the neck and shoulder region. These findings are predominantly based on surveys. Therefore the objective of this study is to conduct a kinematic analysis of occupational posture in dentistry.
METHODS: Twenty one dentists (11 f/10 m; age: 40.1 ± 10.4 years) have participated in this examination. The CUELA-System was used to collect kinematic data of the activities on an average dental workday. A detailed, computer-based task analysis took place parallel to the kinematic examination. Through the synchronization of data collected from both measurements, patterns of posture were arranged chronologically and in conjunction with the tasks performed: (I) "treatment" (II) "office" and (III) "other activities". For the data analysis, characteristic data of joint angular distributions (percentiles P05, P25, P50, P75 and P95) of head, neck and torso at pre-defined tasks were examined and assessed corresponding to ergonomic standards.
RESULTS: Forty one percent of tasks executed on an average dental workday can be categorized as the treatment of patients. These tasked are most frequently performed in "straight back" positions (78.7 %), whereas 20.1 % were carried out in a "twisted or inclined" torso posture, 1.1 % "bowed" and only 0.1 % "bowed and twisted/inclined to the side" upper body position. In particular, it can be observed that in the area of the cervical and thoracic spine the 75th and 95th percentile show worse angular values during treatment than during non-dental tasks. For the period of treatment (at a standardized dental chair construction), a seated position with a strong inclination of the thoracic spine to the right while the lumbar spine is inclined towards the left is adopted.
CONCLUSION: The kinematic analysis of dentists illustrates typical patterns of postures during tasks that are essential to the dental treatment of patients. The postures in the area of the cervical and thoracic spine have higher angular values during treatment compared to other dental tasks. Consistently, appropriate ergonomic design measures to optimize the dental chair and equipment as well as integrated training in ergonomics as part of the study of dentistry to prevent musculoskeletal are recommended.
Background: This study aims at identifying orthodontic activities with the highest frequency of unfavorable/awkward and static postures held over a period of more than 4 s based on kinematic analysis. Moreover, a separate analysis of static postures for orthodontic and non-orthodontic activities serves to evaluate the duration for which these particular postures are assumed.
Methods: In total, 21 (13f/8 m) orthodontists (age: 31.5 ± 3.8 years) participated in this study. CUELA, a personal measurement system, was used to collect kinematic data for all orthodontic activities in a working day. Angle values of the head and torso were evaluated in accordance with ergonomic standards. Only those postures that were held statically for 4 s and longer were selected for further analysis. Alongside the kinematic analysis, the activities performed on-site were also subject to a detailed computerized analysis. The synchronization of data collected from both measurements arranges the patterns of posture found chronologically and in conjunction with the orthodontic activities performed ((I) "treatment" (II) "office" and (III) "other activities").
Results: For (I) we observed an anterior inclination of the head and torso area as well as a twist of the head and neck area to the right. We found anterior back inclination and lateral back torsion to the right for (II) and (III). If, furthermore, we differentiate the duration of static postures, there are primarily short to medium-term (4–30s) static postures identified for (I). Also, categories (II) and (III) predominantly demonstrate static back postures with a duration of up to 30 s. With regard to (II) we observed that the back is ventrally inclined for 10.1% of the total activity duration.
Conclusions: During treatment static strains are observed in the entire head and torso area. On the contrary, static postures prevalent in the torso area are essential for activities of the other categories, particularly office work. These findings allow for a careful selection of unfavorable and static postures for each of the activities performed and help to develop specific preventive measures.
Motion analysis in the field of dentistry : a kinematic comparison of dentists and orthodontists
(2016)
Objectives: To conduct a kinematic comparison of occupational posture in orthodontists and dentists in their workplace.
Design: Observational study.
Setting: Dentist surgeries and departments of orthodontics at university medical centres in Germany.
Participants: A representative sample of 21 (10 female, 11 male) dentists (group G1) and 21 (13 female, 8 male) orthodontists (G2) with one male dropout in G2.
Outcome measures: The CUELA (computer-assisted acquisition and long-term analysis of musculoskeletal loads) system was used to analyse occupational posture. Parallel to the recording through the CUELA system, a software-supported analysis of the activities performed (I: treatment; II: office; III: other activities) was carried out. In line with ergonomic standards the measured body angles are categorised into neutral, moderate and awkward postures. Activities between the aforementioned groups are compared using the stratified van Elteren U test and the Wilcoxon–Mann–Whitney U test. All p values are subject to the Bonferroni–Holm correction. The level of significance is set at 5%.
Results: The percentage of time spent on activities in categories I–II–III was as follows: dentists 41%–23%–36% and orthodontists 28%–37%–35%. The posture analysis of both groups showed, for all percentiles (P5–95), angle values primarily in the neutral or moderate range. However, depending on the activity performed, between 5% and 25% of working hours were spent in unfavourable postures, especially in the head-and-neck area. Orthodontists have a greater tendency than dentists to perform treatment activities with the head and torso in unfavourable positions. The statistically significant differences between the two groups with regard to the duration and the relevance of the activities performed confirm this assumption for all three categories (p<0.01, p<0.05).
Conclusions: Generally, both groups perform treatment activities in postures that are in the neutral or medium range; however, dentists had slightly more unfavourable postures during treatment for a greater share of their work day.
Background: The aim of this pilot study was to analyze postures during the work of neurologists with respect to their occupational activities.
Methods: A total data material of 64.8 h (3885.74 min) of nine (three m/six f) neurologists (assistant physicians) was collected. Kinematic data were collected using the CUELA system (electro-goniometry). In addition, the occupational tasks performed on-site were subject to a detailed objective activity analysis. All activities were assigned to the categories "Office activities" (I), "Measures on patients" (II) and "Other activities" (III). The angle values of each body region (evaluation parameters) were evaluated according to ergonomic ISO standards.
Results: Only 3.4% of the working hours were spent with (II), while 50.8% of time was spent with (I) and 45.8% with (III). All tasks of category (II) revealed an increased ergonomic risk to the head, neck, trunk and back areas. During category (I) especially neck and back movements in the sagittal plane showed higher ergonomic risk levels.
Conclusion: Despite frequently performed awkward body positions in (II), the ergonomic risk is considered as rather low, since the percentage time share totaled only 3.4%. As a result, "Office activities" have been detected as high predictor to cause stress load on the musculoskeletal system in the daily work of neurologists.
Background: How a dentist works, such as the patterns of movements performed daily, is also largely affected by the workstation Dental tasks are often executed in awkward body positions, thereby causing a very high degree of strain on the corresponding muscles. The objective of this study is to detect those dental tasks, during which awkward postures occur most frequently. The isolated analysis of static postures will examine the duration for which these postures are maintained during the corresponding dental, respectively non-dental, activities.
Methods: 21 (11f/10 m) dentists (age: 40.1 ± 10.4 years) participated in this study. An average dental workday was collected for every subject. To collect kinematic data of all activities, the CUELA system was used. Parallel to the kinematic examination, a detailed computer-based task analysis was conducted. Afterwards, both data sets were synchronized based on the chronological order of the postures assumed in the trunk and the head region. All tasks performed were assigned to the categories "treatment" (I), "office" (II) and "other activities" (III). The angle values of each body region (evaluation parameter) were examined and assessed corresponding to ergonomic standards. Moreover, this study placed a particular focus on static positions, which are held statically for 4 s and longer.
Results: For "treatment" (I), the entire head and trunk area is anteriorly tilted while the back is twisted to the right, in (II) and (III) the back is anteriorly tilted and twisted to the right (non-neutral position). Static positions in (I) last for 4–10s, static postures (approx. 60%) can be observed while in (II) and (III) in the back area static positions for more than 30 s are most common. Moreover, in (II) the back is twisted to the right for more than 60 s in 26.8%.
Conclusion: Awkward positions are a major part of a dentists’ work. This mainly pertains to static positions of the trunk and head in contrast to "office work." These insights facilitate the quantitative description of the dentist profession with regard to the related physical load along with the health hazards to the musculoskeletal system. Moreover, the results allow for a selective extraction of the most unfavorable static body positions that dentists assume for each of the activities performed.
Background: Despite the numerous associations of vitamin D with health and disease, vitamin D deficiency is still common from a global perspective. While basic research, clinical and preventive activities grow constantly in vitamin D research, there is no in-depth analysis of the related global scientific productivity available so far.
Methods: Density equalizing mapping procedures (DEMP) were combined with socioeconomic benchmarks using the NewQIS platform.
Results: A total of 25,992 vitamin D-related research articles were identified between 1900 to 2014 with a significant increase (r2 = .6541) from 1900 to 2014. Authors located in Northern America – especially in the USA – distributed the majority of global vitamin D research, followed by their Western European counterparts. DEMP-analysis illustrates that Africa and South America exhibit only minor scientific productivity. Among high-income group countries, Scandinavian nations such as Denmark or Finland (2147.9 and 1607.7 vitamin D articles per GDP in 1000 billion USD) were highly active with regard to socioeconomic figures.
Conclusion: Networks dedicated to vitamin D research are present around the world. Overall, the Northern American and Western European nations occupy prominent positions. However, South American, African and Asian countries apart from Japan only play a minor role in the global research production related to vitamin D. Since vitamin D deficiency is currently increasing in the Americas, Europe and parts of the Middle East, research in these regions may need to be encouraged.
Background: The aim is to investigate to what extent the different oral protections compared to the habitual occlusion affect the upper body posture in statics and during taekwondo-specific movement.
Methods: 12 Taekwondoka (5 f/7 m) of German national team were measured by using a 3d back scanner and an ultrasonic distance measuring (upright stand, taekwondo attack and defense movement, two taekwondo specific combinations) in habitual occlusion, with a custom-made and ready-made mouth protection
Results: There are no significant changes in the upper body posture (p ≥ 0.05). Depending on the dynamic measurements, different significant reactions of the spinal position were found while wearing the custom made mouthguard or the ready-made mouthguard according to the conducted movement.
Conclusion: The measured changes in dynamic movements are not clinical relevant. Based on the positive responses from the participants, the custom-made mouth protection can be recommended combined with an individual analysis.
Objective: Classifications of posture deviations are only possible compared with standard values. However, standard values have been published for healthy male adults but not for female adults.
Design: Observational study.
Setting: Institute of Occupational Medicine, Social Medicine and Environmental Medicine, Goethe-University Frankfurt/Main.
Participants: 106 healthy female volunteers (21–30 years old; 25.1±2.7 years) were included. Their body weight ranged from 46 to 106 kg (60.3±7.9 kg), the heights from 1.53 to 1.82 m (1.69±0.06 m) and the body mass index from 16.9 kg/m² to 37.6 kg/m² (21.1±2.6 kg/m²).
Outcome measures: A three-dimensional back scan was performed to measure the upper back posture in habitual standing. The tolerance ranges and CI were calculated. Group differences were tested by the Wilcoxon Mann-Whitney U test.
Results: In normal posture, the spinal column was marginally twisted to the left, and the vertebrae were marginally rotated to the right. The kyphosis angle is larger than the lumbar angle. Consequently, a more kyphotic posture is observed in the sagittal plane. The habitual posture is slightly scoliotic with a rotational component (scapular depression right, right scapula marginally more dorsally, high state of pelvic right, iliac right further rotated anteriorly).
Conclusions: Healthy young women have an almost ideally balanced posture with minimal ventral body inclination and a marginal scoliotic deviation. Compared with young males, women show only marginal differences in the upper body posture. These values allow a comparison to other studies, both for control and patient data, and may serve as guideline in both clinical practice and scientific studies.
Objectives: Symmetrical dental occlusion blocking is used in dentistry as a quick diagnostic tool to test for potential influences of the craniomandibular system on body sway and weight distribution. This study presents the changes of body sway and pressure distribution in healthy subjects, free of a temporomandibular dysfunction (TMD). Immediate effects between occlusal blocking and rest position on body sway and body weight distribution in general, as well as for both genders and for four age decades will be evaluated.
Materials and methods: 725 (396f/329 m) subjects (neither subjective signs of TMD nor acute/chronic complaints in the musculoskeletal system) volunteered (21 to 60 years) while both genders were divided into four age groups according to decades. A pressure measuring platform was used. Body sway and weight distribution were recorded in two dental occlusion conditions (a) in rest position and (b) symmetrical blocking (bicuspid region) by cotton rolls.
Results: Both, the frontal sway and the sagittal sway reduced by 0.67 mm (t(724) = − 3.9 (p < 0.001)) and by 0.33 mm (t(724) = − 3.4 (p < 0.001)). The relative pressure under the left forefoot increased by 0.33% (t(724) = 2.88 (p < 0.001)) and the relative pressure overall under the forefoot increased by 0.67% (t(724) = − 3.4 (p < 0.001)). Gender-specific, age-specific and BMI-specific reactions could not be identified.
Conclusions: Subjects, free of any TMD and with no complaints of the musculoskeletal system, show small changes of the body sway and weight distribution when biting symmetrically on a cotton roll. These changes are independent of age, gender or body mass index (BMI). Due to the relative large sample size, the presented results can also be seen as norm values when body sway is used as an additional assessment of a TMD.
Background: In order to classify and analyze the parameters of upper body posture, a baseline in the form of standard values is demanded. To this date, standard values have only been published for healthy men aged 18–35 and 41–50 years. Data for male adults aged between 31 and 40 years are lacking.
Methods: The postural parameters of 101 symptom-free male volunteers aged 31–40 (35.58 ± 2.88) years were studied. The mean height of the men was 179.89 ± 7.38 cm, with a mean body weight of 86.36 ± 11.58 kg and an average BMI of 26.70 ± 3.35 kg/m2. By means of video rasterstereography, a 3-dimensional scan of the upper back surface was measured in a habitual standing position. The means or medians, confidence interval, tolerance range, and group comparisons and correlations of BMI and physical activity were calculated for all parameters.
Results: The habitual standing position was found to be almost symmetrical and the axis aligned in the spine, pelvis, and shoulder region, while the spine position was marginally inclined ventrally. The kyphosis angle of the thoracic spine was greater than the lordosis angle of the lumbar spine. All deviations fell under the measurement error margin of 1 mm/1°. The greater the BMI, the greater was the pelvic and scapular distance. The lower the BMI, the further caudally positioned was the right shoulder. The pelvic and scapular distances were also lower with the increasing athleticism of the participants.
Conclusion: The upper body posture of men between the ages of 31 and 40 years was found to be almost symmetrical and axis-conforming, with the kyphosis angle, pelvic distance, and shoulder distance enlarging with increasing BMI. Consequently, postural parameters presented in this survey allow for comparisons with other studies, as well as the evaluation of clinical diagnostics and applications.
Background: The aim of this study was to collect standard reference values of the weight and the maximum pressure distribution in healthy adults aged 18–65 years and to investigate the influence of constitutional parameters on it.
Methods: A total of 416 healthy subjects (208 male / 208 female) aged between 18 and 65 years (Ø 38.3 ± 14.1 years) participated in this study, conducted 2015–2019 in Heidelberg. The age-specific evaluation is based on 4 age groups (G1, 18–30 years; G2, 31–40 years; G3, 41–50 years; G4, 51–65 years). A pressure measuring plate FDM-S (Zebris/Isny/Germany) was used to collect body weight distribution and maximum pressure distribution of the right and left foot and left and right forefoot/rearfoot, respectively.
Results: Body weight distribution of the left (50.07%) and right (50.12%) foot was balanced. There was higher load on the rearfoot (left 54.14%; right 55.09%) than on the forefoot (left 45.49%; right 44.26%). The pressure in the rearfoot was higher than in the forefoot (rearfoot left 9.60 N/cm2, rearfoot right 9.51 N/cm2/forefoot left 8.23 N/cm2, forefoot right 8.59 N/cm2). With increasing age, the load in the left foot shifted from the rearfoot to the forefoot as well as the maximum pressure (p ≤ 0.02 and 0.03; poor effect size). With increasing BMI, the body weight shifted to the left and right rearfoot (p ≤ 0.001, poor effect size). As BMI increased, so did the maximum pressure in all areas (p ≤ 0.001 and 0.03, weak to moderate effect size). There were significant differences in weight and maximum pressure distribution in the forefoot and rearfoot in the different age groups, especially between younger (18–40 years) and older (41–65 years) subjects.
Discussion: Healthy individuals aged from 18 to 65 years were found to have a balanced weight distribution in an aspect ratio, with a 20% greater load of the rearfoot. Age and BMI were found to be influencing factors of the weight and maximum pressure distribution, especially between younger and elder subjects. The collected standard reference values allow comparisons with other studies and can serve as a guideline in clinical practice and scientific studies.
Background: To detect deviations from a normal postural control, standard values can be helpful for comparison purposes. Since the postural control is influenced by gender and age, the aim of the present study was the collection of standard values for women between 31 and 40 years of age.
Methods: For the study, 106 female, subjectively healthy, German subjects aged between 31 and 40 years (35 ± 2.98 years) were measured using a pressure measuring platform.
Results: Their average BMI was 21.60 ± 4.65 kg/m2. The load distribution between left and right foot was almost evenly balanced with a median 51.46% load on the left [tolerance interval (TR) 37.02%/65.90%; confidence interval (CI) 50.06/52.85%] and 48.54% [TR 43.10/62.97%; CI 47.14/49.93%] on the right foot. The median forefoot load was 33.84% [TR 20.68/54.73%; CI 31.67/37.33%] and the rearfoot load was measured at 66.16% [TR 45.27/79.33%; CI 62.67/68.33%]. The median/mean body sway in the sagittal plane was measured 12 mm [TR 5.45/23.44 mm; CI 11.00/14.00 mm] and 8.17 mm in the frontal plane [TR 3.33/19.08 mm; CI 7.67/9.33 mm]. The median of the ellipse area is 0.72 cm2 [TR 0.15/3.69 cm2; CI 0.54/0.89°]. The ellipse width has a median of 0.66 cm [TR 0.30/1.77 cm; CI 0.61/0.78 cm] and the height of 0.33 cm [TR 0.13/0.71 cm; CI 0.30/0.37 cm]. The ellipse angle (sway, left forefoot to right rearfoot) has a mean of − 19.34° [TR − 59.21/− 0.44°; CI − 22.52/− 16.16°] and the ellipse angle sway from right forefoot to left rearfoot has a mean of 12.75° [TR 0.09/59.09°; CI 9.00/16.33°].
Conclusion: The right-to-left ratio is balanced. The forefoot-to-rearfoot ratio is approximately 1:2. Also, the body sway can be classified with 12 and 8 mm as normal. The direction of fluctuation is either approx. 19° from the left forefoot to the right rearfoot or approx. 13° the opposite. Body weight, height, and BMI were comparable to the German average of women in a similar age group, so that the measured standard values are representative and might serve as baseline for the normal function of the balance system in order to support the diagnosis of possible dysfunctions in postural control.
Standard values of the upper body posture in healthy adults with special regard to age, sex and BMI
(2023)
In order to classify and analyze the parameters of upper body posture in clinical or physiotherapeutic settings, a baseline in the form of standard values with special regard to age, sex and BMI is required. Thus, subjectively healthy men and women aged 21–60 years were measured in this project. The postural parameters of 800 symptom-free male (n = 397) and female (n = 407) volunteers aged 21–60 years (Ø♀: 39.7 ± 11.6, Ø ♂: 40.7 ± 11.5 y) were studied. The mean height of the men was 1.8 ± 0.07 m, with a mean body weight of 84.8 ± 13.1 kg and an average BMI of 26.0 ± 3.534 kg/m2. In contrast, the mean height of the women was 1.67 ± 0.06 m, with a mean body weight of 66.5 ± 12.7 kg and an average BMI of 23.9 ± 4.6 kg/m2. By means of video rasterstereography, a 3-dimensional scan of the upper back surface was measured when in a habitual standing position. The means or medians, confidence intervals, tolerance ranges, the minimum, 2.5, 25, 50, 75, 97.5 percentiles and the maximum, plus the kurtosis and skewness of the distribution, were calculated for all parameters. Additionally, ANOVA and a factor analyses (sex, BMI, age) were conducted. In both sexes across all age groups, balanced, symmetrical upper body statics were evident. Most strikingly, the females showed greater thoracic kyphosis and lumbar lordosis angles (kyphosis: Ø ♀ 56°, Ø♂ 51°; lordosis: Ø ♀ 49°, Ø♂ 32°) and lumbar bending angles (Ø ♀ 14°, Ø♂ 11°) than the males. The distance between the scapulae was more pronounced in men. These parameters also show an increase with age and BMI, respectively. Pelvic parameters were independent of age and sex. The upper body postures of women and men between the ages of 21 and 60 years were found to be almost symmetrical and axis-conforming with a positive correlation for BMI or age. Consequently, the present body posture parameters allow for comparisons with other studies, as well as for the evaluation of clinical (interim) diagnostics and applications.
Objectives: The aim of this study was to investigate the relationship between anamnestic, axiographic and occlusal parameters and postural control in healthy women aged between 41 and 50 years. Materials and methods: A total of 100 female participants aged between 41 and 50 (45.12 ± 2.96) years participated in the study. In addition to completing a general anamnesis questionnaire, lower jaw movements were measured axiographically, dental occlusion parameters were determined using a model analysis and postural parameters were recorded using a pressure measurement platform. The significance level was 5%. Results: An increasing weight and a rising BMI lead to a weight shifted from the rearfoot (p ≤ 0.01/0.04) to the forefoot (p ≤ 0.01/0.02). A limited laterotrusion on the right resulted in a lower forefoot load and an increased rearfoot load (p ≤ 0.01). Laterotrusion to the left (extended above the standard) showed a lower frontal sway (p ≤ 0.02) and a reduced elliptical area, height and width (p ≤ 0.01, 0.02, 0.03). Thus, the extent of deviation correlated with reduced right forefoot loading (p ≤ 0.03) and the extent of deflection correlated with increased left foot loading (p ≤ 0.01). The higher the extent of angle class II malocclusion, the larger the ellipse area (p ≤ 0.04) and the ellipse height (p ≤ 0.02) resulted. Conclusions: There is a connection between weight, BMI and laterotrusion, as well as between angle class II malocclusion and postural control in women aged between 41 and 50 years. Interdisciplinary functional examinations of mandibular movements treating possible limitations can be conducive for an improvement of postural control. Clinical relevance: Angle class II malocclusion has a negative influence on postural control.
Objectives The following study analyses the influence of risk factors among the occupational group of truck drivers on postural control and body mass index (BMI).
Design Observational study.
Setting One motorway station close to several highways in Germany.
Participants 180 truck drivers (177 male/3 female), aged 21–65 years old, took part in this study.
Outcome measures Postural control was examined using a pressure plate. In order to examine the influence of body weight (BMI) and working years on postural control, subjects were divided into samples of five and three groups, respectively. Furthermore, it was evaluated whether the subjects suffered from back pain. For data analysis, the Kruskal-Wallis test was used as the data were not normally distributed. Once the p value of the Kruskal-Wallis test was p≤0.05, the Conover-Iman comparison and afterwards the Bonferroni-Holm correction were used. The significance level was set at α ≤0.05.
Results Regarding the number of working years, a significant increase of frontal (p≤0.04) and sagittal (p≤0.001) sway were observed. The correlation of the five BMI groups with the number of working years demonstrates that an increase of the working years leads to an increase of BMI (p≤0.03). Furthermore, the majority of truck drivers participating in this study suffered from back pain (61.7%).
Conclusions BMI and musculoskeletal impairment are indicators of health risk factors. In this study, it is shown that an increasing number of working years and an increasing BMI lead to a decrease in frontal and sagittal postural sway. In addition, the number of working years correlates with body weight and back pain.
Objective: The influence of the jaw position on postural control, body posture, walking and running pattern has been reported in the literature. All these movements have in common that a relatively small, but well controlled muscle activation is required. The induced effects on motor output through changed jaw positions have been small. Therefore, it has been questioned if it could still be observed in maximal muscle activation.
Method: Twenty-three healthy, mid age recreational runners (mean age = 34.0 ± 10.3 years) participated in this study. Three different jump tests (squat jump, counter movement jump, and drop jumps from four different heights) and three maximal strength tests (trunk flexion and extension, leg press of the right and left leg) were conducted. Four different dental occlusion conditions and an additional familiarization condition were tested. Subjects performed the tests on different days for which the four occlusion conditions were randomly changed.
Results: No familiarization effect was found. Occlusion conditions with a relaxation position and with a myocentric condylar position showed significantly higher values for several tests compared to the neutral condition and the maximal occlusion position. Significance was found in the squat jump, countermovement jump, the drop jump from 32cm and 40cm, trunk extension, leg press force and rate of force development. The effect due to the splint conditions is an improvement between 3% and 12% (min and max). No influence of the jaw position on symmetry or balance between extension and flexion muscle was found.
Conclusion: An influence of occlusion splints on rate of force development (RFD) and maximal strength tests could be confirmed. A small, but consistent increase in the performance parameters could be measured. The influence of the occlusion condition is most likely small compared to other influences as for example training status, age, gender and circadian rhythm.
Introduction: The effects of manipulated dental occlusion on body posture has been investigated quite often and discussed controversially in the literature. Far less attention has been paid to the influence of dental occlusion position on human movement. If human movement was analysed, it was mostly while walking and not while running. This study was therefore designed to identify the effect of lower jaw positions on running behaviour according to different dental occlusion positions.
Methods: Twenty healthy young recreational runners (mean age = 33.9±5.8 years) participated in this study. Kinematic data were collected using an eight-camera Vicon motion capture system (VICON Motion Systems, Oxford, UK). Subjects were consecutively prepared with four different dental occlusion conditions in random order and performed five running trials per test condition on a level walkway with their preferred running shoes. Vector based pattern recognition methods, in particular cluster analysis and support vector machines (SVM) were used for movement pattern identification.
Results: Subjects exhibited unique movement patterns leading to 18 clusters for the 20 subjects. No overall classification of the splint condition could be observed. Within individual subjects different running patterns could be identified for the four splint conditions. The splint conditions lead to a more symmetrical running pattern than the control condition.
Discussion: The influence of an occlusal splint on running pattern can be confirmed in this study. Wearing a splint increases the symmetry of the running pattern. A more symmetrical running pattern might help to reduce the risk of injuries or help in performance. The change of the movement pattern between the neutral condition and any of the three splint conditions was significant within subjects but not across subjects. Therefore the dental splint has a measureable influence on the running pattern of subjects, however subjects individuality has to be considered when choosing the optimal splint condition for a specific subject.
Introduction: Musicians often perform in forced postures over a long period of time, which in the worst case may lead to playing-related musculoskeletal disorders. In this context, the ergonomics of the musician's chair (construction and surface quality) can be an influencing factor, with impact on the seating position of the upper body and the pressure distribution of the bottom. Therefore, the relationship between different musician chairs and musicians of different playing levels (professional, amateur or student) was analyzed in order to gain useful insights whether playing experience, playing level, playing style (symmetrical or asymmetrical) or gender have an impact.
Method: The total dataset of 47 musicians (3 playing levels: professional, amateur, student) were analysed on six musician chairs with different ergonomic layout. Sitting on each chair without instrument (condition 1) and with instrument (condition 2), the upper body posture (videorasterstereography) and the seat pressure (load distribution) were recorded.as Also, a subjective assessment concerning constitutional data, sitting behaviour, prevailing pain in the musculoskeletal system, sport activity and chair comfort rating, was completed using a questionnaire.
Results: There were significant differences shown in 6 of 17 variables, where all between and within factors were accounted for with a MANOVA. Two measurements of the upper body posture (scapular distance and scapular height) differentiated between playing level. Four of the pressure measurements (pressure under the sit bone and the thigh for the left and the right side) differentiated between chairs and the two conditions (with and without instrument). Chairs with soft cushioning had a mean pressure reduction of about 30%. The pressure was increased by about 10% while playing an instrument. Subjective rating was correlated to age for some of the chairs.
Discussion: Differences between chairs are mainly associated with the pressure distribution under the sitting surface. Playing with an instrument puts an additional force onto the surface of the chair that is more than the weight of the instrument. No relationship between pressure data and upper body posture data could be found. Therefore, it can be speculated that the intersubject variability is larger than systematic differences introduced by the chair or instrument.
Background: Effects of playing high stringed bow instruments on the upper body posture have not been analysed so far. The instrument-specific seating position when playing in an orchestra is compared to the habitual seating position.
Methods: Three dimensional back scans were performed in 13 professional violinists and viola players of a radio orchestra (8 f / 5 m). Trunk position in their habitual seating position and in the instrument- specific seating position imitating playing was compared. Statistical differences were calculated using Wilcoxon Matched Pairs Test with Bonferroni Holm correction.
Results: Significant differences were found between the seated position with instrument and without (p < 0.001, 0.03, 0.02 or 0.01) in the spine (trunk length, sagittal trunk decline, lumbar bending angle, maximal rotation, standard deviation rotation, lumbar lordosis), the shoulder (scapula distance, scapula rotation, scapula angle right) and pelvis distance.
Conclusions: Playing an instrument changes the static seating position by increased rotation of the spine and specific shoulder adaptations holding the instrument (left arm) and the bow (right arm), with minor effects on the pelvis. This forced position may result in chronic health effects. The method used in this study is an approach to better understand the involved muscular structures and possible resulting health damages.
BACKGROUND: Geographical variation of the general practitioner (GP) workforce is known between rural and urban areas. However, data about the variation between and within urban areas are lacking.
METHOD: We analyzed distribution patterns of GP full time equivalents (FTE) in German cities with a population size of more than 500,000. We correlated their distribution with area measures of social deprivation in order to analyze preferences within neighborhood characteristics. For this purpose, we developed two area measures of deprivation: Geodemographic Index (GDI) and Cultureeconomic Index (CEI).
RESULTS: In total n = 9034.75 FTE were included in n = 14 cities with n = 171 districts. FTE were distributed equally on inter-city level (mean: 6.49; range: 5.12-7.20; SD: 0.51). However, on intra-city level, GP distribution was skewed (mean: 6.54; range: 1.80-43.98; SD: 3.62). Distribution patterns of FTE per 10^4 residents were significantly correlated with GDI (r = -0.49; p < 0.001) and CEI (r = -0.22; p = 0.005). Therefore, location choices of GPs were mainly positively correlated with 1) central location (r = -0.50; p < 0.001), 2) small household size of population (r = -0.50; p < 0.001) and 3) population density (r = 0.35; p < 0.001).
CONCLUSION: Intra-city distribution of GPs was skewed, which could affect the equality of access for the urban population. Furthermore, health services planners should be aware of GP location preferences. This could be helpful to better understand and plan delivery of health services. Within this process the presented Geodemographic Index (GDI) could be of use.
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.
In the application of range of motion (ROM) tests there is little agreement on the number of repetitions to be measured and the number of preceding warm-up protocols. In stretch training a plateau in ROM gains can be seen after four to five repetitions. With increasing number of repetitions, the gain in ROM is reduced. This study examines the question of whether such an effect occurs in common ROM tests. Twenty-two healthy sport students (10 m/12 f.) with an average age of 25.3 ± 1.94 years (average height 174.1 ± 9.8 cm; weight 66.6 ± 11.3 kg and BMI 21.9 ± 2.0 kg/cm2) volunteered in this study. Each subject performed five ROM tests in a randomized order—measured either via a tape measure or a digital inclinometer: Tape measure was used to evaluate the Fingertip-to-Floor test (FtF) and the Lateral Inclination test (LI). Retroflexion of the trunk modified after Janda (RF), Thomas test (TT) and a Shoulder test modified after Janda (ST) were evaluated with a digital inclinometer. In order to show general acute effects within 20 repetitions we performed ANOVA/Friedman-test with multiple comparisons. A non-linear regression was then performed to identify a plateau formation. Significance level was set at 5%. In seven out of eight ROM tests (five tests in total with three tests measured both left and right sides) significant flexibility gains were observed (FtF: p < 0.001; LI-left/right: p < 0.001/0.001; RF: p = 0.009; ST-left/right: p < 0.001/p = 0.003; TT-left: p < 0.001). A non-linear regression with random effects was successfully applied on FtF, RF, LI-left/right, ST-left and TT-left and thus, indicate a gradual decline in the amount of gained ROM. An acute effect was observed in most ROM tests, which is characterized by a gradual decline of ROM gain. For those tests, we can state that the acute effect described in the stretching literature also applies to the performance of typical ROM tests. Since a non-linear behavior was shown, it is the decision of the practitioner to weigh up between measurement accuracy and expenditure. Researchers and practitioners should consider this when applying ROM assessments to healthy young adults.
In the context of workplace health promotion, physical activity programs have been shown to reduce musculoskeletal diseases and stress, and to improve the quality of life. The aim of this study was to examine the effects of using the “five-Business” stretch training device for office workers on their quality of life. A total of 313 office workers (173m/137f) participated voluntarily in this intervention–control study with an average age of 43.37 ± 11.24 (SD) years, 175.37 ± 9.35 cm in height and 75.76 ± 15.23 kg in weight, with an average BMI of 24.5 ± 3.81 kg/m2. The participants completed the stretch training twice a week for approximately 10 minutes for a duration of 12 weeks. The SF-36 questionnaire was used to evaluate the effectiveness of the intervention at baseline and after 12 weeks. Significantly improved outcomes in mental sum score (p = 0.008), physical functioning (p < 0.001), bodily pain (p = 0.01), vitality (p = 0.025), role limitations due to physical problems (p = 0.018) and mental health (p = 0.012) were shown after the stretching training. The results suggest that a 12-week stretching program for office desk workers is suitable to improve significantly their health-related quality of life.
Background: The aim of this pilot study was to analyze the work of neurologists regarding static posture (> 4 s) and to identify awkward postures. Methods: A total of 9 neurologists (assistant physicians; 3 male, 6 female) participated in this study. Kinematic data were collected using the computer-assisted acquisition and long-term analysis of musculoskeletal loads (CUELA; IFA, Sankt Augustin, Germany) system. Daily work (“office work,” “measures on patients,” and “other activities”) was analyzed with a computer-based task analysis. Results: During ”measures on patients,” more than 80% of the total percentage of non-neutral posture was assumed with a flexed position of the head and entire back, both during “blood collection” (4.7% of the time) and while “placing intravenous catheters” (8.3% of the time). In contrast, long static postures (> 30 s) in the head and neck area, including the thoracic spine, were adopted during “office work.” Despite the increased total percentage of non-neutral attitudes during measures on patients, the time share of 3.4% of the total working time is so small that the risk for developing musculoskeletal disorders (MSD) is negligible. In contrast, office work, which comprises 50.8% of the total working time and longer static postures, has a potential risk for the development of MSD. Conclusion: The present study is the first kinematic pilot analysis in the field of in-patient neurological assistants. Non-neutral as well as static postures in everyday work could be identified. Potential MSD can be reduced by optimizing the working height and by taking regular breaks to loosen the musculoskeletal system.
The occupation of dental assistants (DAs) involves many health risks of the musculoskeletal system due to static and prolonged work, which can lead to musculoskeletal disorders (MSDs). The aim of the study was to investigate the prevalence of MSDs in DAs in Germany. Methods: For this purpose, an online questionnaire analyzed 406 (401 female participants and 5 male participants, 401w/5m) DAs. It was based on the Nordic Questionnaire (lifetime, 12-month, and seven-day MSDs’ prevalence separated into neck, shoulder, elbow, wrist, upper back, lower back, hip, knee, and ankle), and occupational and sociodemographic questions as well as questions about specific medical conditions. Results: 98.5% of the participants reported complaints of at least one body region in their lives, 97.5% reported at least one complaint in the last 12 months and 86.9% affirmed at least one complaint in the last seven days. For lifetime, 12-month and seven-day prevalence, the neck was the region that was most affected followed by the shoulder, the upper back and the lower back. Conclusion: The prevalence of MSDs among German (female) DAs was very high. The most affected area is the neck, followed by the shoulder, the lower back, and the upper back. It, therefore, seems necessary to devote more attention to ergonomics at the working practice of DAs as well in education and in dental work.
Background: Musculoskeletal disorders (MSD) are common among dental professionals. The most common areas affected are the trunk, neck, shoulders and wrists. Current evidence suggests that the causes of MSD can be found in the physical demands of the profession. Posture and movement during treatment is influenced by the arrangement of the treatment concept (patient chair, equipment and cabinets). It has not been investigated whether the ergonomic risk differs between the treatment concepts.
Methods: To evaluate the prevalence of MSD in dental professionals, 1000 responses will be collected from a nationwide (Germany) online questionnaire (mod. Nordic Questionnaire and mod. Meyer questionnaire). In order to assess the ergonomic risk of the treatment techniques used in the four treatment concepts, 3D movement analyses are carried out with inertial sensors. For this purpose, 20 teams of dentists and dental assistants from four dental fields of specializations (generalists, orthodontists, endodontists and oral surgeons) and a student control group will be recruited. Each team will execute field specific standardized treatments at a dummy head. Measurements are carried out in each of the four treatment concepts. The data will be analyzed using the Rapid Upper Limb Assessment (RULA) which will be modified for the evaluation of objective data.
Conclusions: On the basis of these investigations, a substantial gain of knowledge regarding work-related MSD in the field of dentistry and its potential biomechanical causes is possible. For the first time, objective and differentiated comparisons between the four treatment concepts are possible for different fields of dental specialization. Up to now, statically held positions of the trunk and proximal upper extremities, but also the repetitive movements of the hands have been considered a risk for MSD. Since both are included in the RULA, dental activities can be assessed in a detailed but also global manner with regard to ergonomic risks.
Musculoskeletal disorders of the trunk and neck are common among cleaners. Vacuum cleaning is a demanding activity. The aim of this study was to present the movement profile of the trunk and neck during habitual vacuuming. The data were collected from 31 subjects (21f./10 m) using a 3D motion analysis system (Xsens). 10 cycles were analysed in vacuuming PVC and carpet floors with 8 vacuum cleaners. The joint angles and velocities were represented statistically descriptive. When vacuuming, the trunk is held in a forwardly inclined position by a flexion in the hip and rotated from this position. In the joint angles and velocities of the spine, the rotation proved to be dominant. A relatively large amount of movement took place in the cervical spine and also in the lumbar spine. The shown movement profile is rather a comfort area of vacuuming which may serve as a reference for ergonomics in vacuuming.
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.
Background: Dentists are at a higher risk of suffering from musculoskeletal disorders (MSD) than the general population. However, the latest study investigating MSD in the dental profession in Germany was published about 20 years ago. Therefore, the aim of this study was to reveal the current prevalence of MSD in dentists and dental students in Germany. Methods: The final study size contained 450 (287 f/163 m) subjects of different areas of specialization. The age of the participants ranged from 23 to 75 years. The questionnaire consisted of a modified version of the Nordic Questionnaire, work-related questions from the latest questionnaire of German dentists, typical medical conditions and self-developed questions. Results: The overall prevalence showed that dentists suffered frequently from MSD (seven days: 65.6%, twelve months: 92%, lifetime: 95.8%). The most affected body regions included the neck (42.7%–70.9%–78.4%), shoulders (29.8%–55.6%–66.2%) and lower back (22.9%–45.8%–58.7%). Overall, female participants stated that they suffered from pain significantly more frequently, especially in the neck, shoulders and upper back. Conclusion: The prevalence of MSD among dentists, especially in the neck, shoulder and back area, was significantly higher than in the general population. In addition, women suffered more frequently from MSD than men in almost all body regions.
Background: Dentists (Ds) and dental assistants (DAs) have a high lifetime prevalence of musculoskeletal disorders (MSDs). In this context, it is assumed that they have an increased intake of substances such as pain medication. Currently, there exist no data on the use of medication among Ds and DAs with MSDs in Germany. Methods: The online questionnaire (i.e., the Nordic Questionnaire) analysed the medical therapies used by 389 Ds (240 f/149 m) and 406 DAs (401 f/5 m) to treat their MSDs. Results: Ds (28.3–11.5%) and DAs (29.4–10.3%) with MSDs took medication depending on the affected body region. A trend between the Ds and DAs in the intake of drug therapy and the frequency was found for the neck region (Ds: 21.1%, DAs: 28.7%). A single medication was taken most frequently (Ds: 60.0–33.3%, DAs: 71.4–27.3%). The frequency of use varied greatly for both occupational groups depending on the region affected. Conclusion: Ds and DAs perceived the need for medical therapies because of their MSDs. Painkillers such as ibuprofen and systemic diclofenac were the medications most frequently taken by both occupational groups. The intake of pain killers, most notably for the neck, should prevent sick leave.
Background: dental professionals suffer frequently from musculoskeletal disorders (MSD). Dentists and dental assistants work closely with each other in a mutually dependent relationship. To date, MSD in dental assistants have only been marginally investigated and compared to their occurrence in dentists. Therefore, the aim of this study was to compare the prevalence of MSD between dentists and dental assistants by considering occupational factors, physical activity and gender. Methods: This was a cross-sectional observational study. A Germany-wide survey, using a modified version of the Nordic Questionnaire and work-related questions, was applied. In total, 2548 participants took part, of which 389 dentists (240 females and 149 males) and 322 dental assistants (320 females and 2 males) were included in the analysis. Data were collected between May 2018 and May 2019. Differences between the dentists and dental assistants were determined by using the Chi2 test for nominal and the Wilcoxon–Mann–Whitney U test for both ordinal and non-normally distributed metric data. Results: A greater number of dental assistants reported complaints than dentists in all queried body regions. Significant differences in the most affected body regions (neck, shoulders, wrist/hands, upper back, lower back and feet/ankles) were found for the lifetime prevalence, annual prevalence and weekly prevalence. Data from the occupational factors, physical activity and gender analyses revealed significant differences between dentists and dental assistants. Conclusions: Dental assistants appear to be particularly affected by MSD when compared to dentists. This circumstance can be explained only to a limited extent by differences in gender distribution and occupational habits between the occupations.
Background: In general, the prevalence of work-related musculoskeletal disorders (WMSD) in dentistry is high, and dental assistants (DA) are even more affected than dentists (D). Furthermore, differentiations between the fields of dental specialization (e.g., general dentistry, endodontology, oral and maxillofacial surgery, or orthodontics) are rare. Therefore, this study aims to investigate the ergonomic risk of the aforementioned four fields of dental specialization for D and DA on the one hand, and to compare the ergonomic risk of D and DA within each individual field of dental specialization. Methods: In total, 60 dentists (33 male/27 female) and 60 dental assistants (11 male/49 female) volunteered in this study. The sample was composed of 15 dentists and 15 dental assistants from each of the dental field, in order to represent the fields of dental specialization. In a laboratory setting, all tasks were recorded using an inertial motion capture system. The kinematic data were applied to an automated version of the Rapid Upper Limb Assessment (RULA). Results: The results revealed significantly reduced ergonomic risks in endodontology and orthodontics compared to oral and maxillofacial surgery and general dentistry in DAs, while orthodontics showed a significantly reduced ergonomic risk compared to general dentistry in Ds. Further differences between the fields of dental specialization were found in the right wrist, right lower arm, and left lower arm in DAs and in the neck, right wrist, right lower arm, and left wrist in Ds. The differences between Ds and DAs within a specialist discipline were rather small. Discussion: Independent of whether one works as a D or DA, the percentage of time spent working in higher risk scores is reduced in endodontologists, and especially in orthodontics, compared to general dentists or oral and maxillofacial surgeons. In order to counteract the development of WMSD, early intervention should be made. Consequently, ergonomic training or strength training is recommended.
Comparative values are essential for the classification of orthopedic abnormalities and the assessment of a necessary therapy. At present, reference values for the upper body posture for healthy, male adults exist for the age groups of 18–35, 31–40 and 41–50 years. However, corresponding data on the decade of 51 to 60 year-old healthy men are still lacking. 23 parameters of the upper body posture were analyzed in 102 healthy male participants aged 51–60 (55.36 ± 2.78) years. The average height was 180.76 ± 7.81 cm with a weight of 88.22 ± 14.57 kg. The calculated BMI was 26.96 ± 3.92 kg/m2. In the habitual, upright position, the bare upper body was scanned three-dimensionally using video raster stereography. Mean or median values, confidence intervals, tolerance ranges and group comparisons, as well as correlations of BMI and physical activity, were calculated for all parameters. The spinal column parameters exhibited a good exploration of the frontal plane in the habitual standing position. In the sagittal plane, a slight, ventral inclination of the trunk with an increased kyphosis angle of the thoracic spine and increased thoracic bending angle was observed. The parameters of the pelvis showed a pronounced symmetry with deviations from the 0° axis within the measurement error margin of 1 mm/1°. The scapula height together with the scapula angles of the right and left side described a slightly elevated position of the left shoulder compared to the right side. The upper body posture is influenced by parameters of age, height, weight and BMI. Primarily there are significant correlations to measurements of trunk lengths D (age: p ≤ 0.02, rho = -0.23; height: p ≤ 0.001, rho = 0.58; weight: p ≤ 0.001, rho = 0.33), trunk lengths S (age: p ≤ 0.01, rho = -0.27; height: p ≤ 0.001, rho = 0.58; weight: p ≤ 0.001, rho = 0.32), pelvic distance (height: p ≤ 0.01, rho = 0.26; weight: p ≤ 0.001, rho = 0.32; BMI: p ≤ 0.03, rho = 0.22) and scapula distance (weight: p ≤ 0.001, rho = .32; BMI: p ≤ 0.01, rho = 0.27), but also to sagittal parameters of trunk decline (weight: p ≤ 0.001, rho = -0.29; BMI: p ≤ 0.01, rho = -0.24), thoracic bending angle (height: p ≤ 0.01, rho = 0.27) and kyphosis angle (BMI: p ≤ 0.03, rho = 0.21). The upper body posture of healthy men between the ages of 51 and 60 years was axially almost aligned and balanced. With the findings of this investigation and the reference values obtained, suitable comparative values for use in clinical practice and for further scientific studies with the same experimental set-up have been established.
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.
Introduction: Studies of vocational ballet students are sparce. In particular, there is a lack of gender comparisons. The aim of the present study, therefore, was to give a musculoskeletal and sociodemographic description of the typical vocational ballet student in gender comparison. Methods: In this study, n = 414 female and n = 192 male students of the John Cranko School (JCS), aged between 5 and 22 years (Mean ± SD: 13.9 ± 3.5), were examined by an experienced orthopedist and dance physician. Results: Males started ballet (5.8/8.2 years, p < 0.001) and training at later age than females (13.5/14.6 years, p < 0.05). There was a high prevalence of low body weight among both sexes; however, particularly among female participants (58.4/16.2%, p < 0.001). Both sexes showed a large external rotation of the hip (f/m: 59/62°, p < 0.001), a large turnout (f/m: 82/86°, p < 0.01), high values for plantarflexion of the ankle joint (f/m: 72/68°, p < 0.001) and dorsiflexion of the metatarsophalangeal joint of the big toe (f/m: 90/87°, p < 0.001). Discussion: Differences in ballet-specific characteristics between genders (f/m) are converging and are smaller than described in the past. The particularly high prevalence of low body weight among students in the vocational training sector, particularly among females, highlights the need for deeper diagnostic investigation.
Up to the present, there has been a lack of studies on the skin health of professional and recreational dancers. Dancers are at risk of skin diseases due to contact with allergenic or irritating substances and working in humid environments. The aim of the present study was, therefore, to examine skin health in two different dance styles and training periods. Methods: Physical dermatological examination of professional dancers (PD; n = 35) and Latin American formation dancers (LD; n = 79) after a 4-week period of recovery (T0) and a period of high training or work load (T1). Results: PD are significantly more frequently affected by skin dermatoses than LD (T0, p = 0.004) (frontal traction alopecia, hair loss, facial seborrhoea, xerosis cutis of the trunk and extremities, and facial folliculitis). The following significant differences between the sexes were observed in the LD: more folliculitis of the trunk in male subjects (T0 and T1, p = 0.009), more frequent xerosis cutis of the extremities (p < 0.001) and perioral dermatitis in female subjects (T1, p = 0.043). Subjects with skin lesions trained more frequently, performed more times per year, and had longer dance experience. Discussion: Based on the findings, preventive measures for skin protection (especially informing dancers about skin health) are necessary. At the same time, further studies on this topic are important.
Background: Temporary occlusal changes and their influence on the upper body statics are still controversially discussed. Furthermore, concrete statements on whether age- or gender-specific differences in neurophysiological reactions exist are missing. Therefore, it is the aim of this study to evaluate the immediate effects of a symmetrical occlusion blocking on the upper body posture. These effects shall be investigated for both genders and for a larger age range.
Methods: In this study, 800 (407f/393 m) subjects volunteered aged from 21 to 60 years. Both genders were divided into four age groups according to decades. The three-dimensional upper body posture was measured by using the rasterstereography (ABW-Bodymapper). The habitual static posture was measured in two dental occlusion conditions (a) in rest position and (b) symmetrical blocking in the bicuspid region by cotton rolls.
Results: A significant reduction of the trunk length (0.72 mm; p < 0.001), an increase of the lumbar (0.30°; p < 0.001) and the thoracic bending angle (0.14°; p = 0.001), a reduction of the spinal forward decline (0.16°; p < 0.001) and a reduction of the scapular distance (0.36 mm; p = 0.001) was found. Gender-specific reactions can only be recorded in scapular distance, in that regard men reduce this distance while over all age groups women did not show a significant change.
Discussion: Slight gender- and age-independent reactions due to a symmetric occlusion blockade are shown: A gender independent reaction of the spinal related variables in the sagittal plane (thoracic and lumbar flexion angle, trunk length, spinal forward decline). In addition, a gender specific change of the shoulder blade distance could be observed, where men reduced the distance while female did not show a change. However, since these reactions are of a minimum amount, it can be concluded that neurophysiological compensation mechanisms work equally well regardless of age and sex, and the upper body posture of healthy people changes only very slightly due to a temporarily symmetrical altered bite position.
Standard reference values of the upper body posture in healthy middle-aged female adults in Germany
(2021)
In order to classify and analyze the parameters of upper body posture, a baseline in form of standard values is demanded. To this date, standard values have only been published for healthy young women. Data for female adults between 51 and 60 years are lacking. 101 symptom-free female volunteers aged 51–60 (55.16 ± 2.89) years. The mean height of the volunteers was 1.66 ± 0.62 m, with a mean body weight of 69.3 ± 11.88 kg and an average BMI of 25.02 ± 4.55 kg/m2. By means of video raster stereography, a 3D-scan of the upper back surface was measured in a habitual standing position. The confidence interval, tolerance range and ICCs were calculated for all parameters. The habitual standing position is almost symmetrical in the frontal plane the most prominent deviation being a slightly more ventral position of the left shoulder blade in comparison to the right. The upper body (spine position) is inclined ventrally with a minor tilt to the left. In the sagittal plane, the kyphosis angle of the thoracic spine is greater than the lordosis angle of the lumbar spine. The pelvis is virtually evenly balanced with deviations from an ideal position falling under the measurement error margin of 1 mm/1°. There were also BMI influenced postural variations in the sagittal plane and shoulder distance. The ICCs are calculated from three repeated measurements and all parameters can be classified as "almost perfect". Deflections from an ideally symmetric spinal alignment in women aged 51–60 years are small-scaled, with a minimal frontal-left inclination and accentuated sigmoidal shape of the spine. Postural parameters presented in this survey allow for comparisons with other studies as well as the evaluation of clinical diagnostics and applications.
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.
Objectives: The range of motion (ROM) of the cervical spine and postural stability are important for an economical and motorically adequate adaptation of the body to any situation. Therefore, this study aims to analyze whether these two components of postural and movement control can be influenced by means of a splint in a centric position compared to habitual occlusion.
Methods: 38 recreational male athletes volunteered. Cervical spine ROM was recorded using an ultrasound system and the a pressure measuring plate for postural stability (length of center of pressure (CoP) movement, area of CoP). The two dental occlusion conditions employed were the habitual occlusion and wearing a splint in an idealized, condylar position close to the centric position. Level of significance was set at ρ ≤ 0.05.
Results: The cervical spine mobility increased significantly by wearing the splint regarding rotation to the left (+3.9%) and right (+2.7%) and lateral flexion to the left (+4.4%) and right (+6.7%). Wearing the splint reduced the area of sway deflections by about 31.5% in the bipedal stance and by about 2.4% (left) and 28.2% (right) in the unipedal stance. The CoP trace was reduced in the sagittal plane by approximately 8.2% in the right single-leg stance.
Conclusions: The major findings seem to demonstrate that wearing a splint that keeps the jaw close to the centric relation may increase the cervical ROM and may improve balance stability in male recreational athletes. Changing the jaw relation in athletes can possibly aid the release of performance potentials by improving coordination skills.
Background: A good physician should be empathic and altruistic, among other qualities. Therefore, the levels of socially undesirable personality traits (Dark Triad) as well as implicit motives of achievement, affiliation and power (Multi-Motive Grid) among medical students as future physicians were analyzed at two different points in their medical training.
Methods: This study includes 380 medical students in their first year and 217 in their third year in Germany. All participants completed the Dirty Dozen (DD) and Multi-Motive Grid (MMG) questionnaires at the end of two different classes as paper-and-pencil tests. Relevant differences of the Dark Triad traits between the medical students and reference sample and the two different cohorts, as well as their implicit motives, the associations of Dark Triad traits and MMG components and gender differences of the Dark Triad traits were calculated.
Results: There were no significant group differences between year one and year three medical students in narcissism, psychopathy and Machiavellianism (Dark Triad). There were no significant differences between the medical students and reference sample except in psychopathy. Male students scored significantly higher in the Dark Triad traits than female students. In the MMG, first-year students scored significantly higher levels in Fear of Rejection, and lower levels in Hope of Success and Hope of Power than the third-year students. Some associations were found between narcissism and Machiavelliansim with Hope of Success, Hope of Power and Fear of power.
Conclusions: Dark Triad traits already appear to exist before the commencement of medical studies. These traits do not differ significantly between the medical students and reference sample; only a few MMG components seem to differ at different stages of their studies. This lack of differences between the medical students and validation cohort indicates that tests based on (undesirable) personality traits are not suitable criteria for the admission selection of medical students.