Patients after total hip arthroplasty (THA) suffer from lingering musculoskeletal restrictions. Three-dimensional (3D) gait analysis in combination with machine-learning approaches is used to detect these impairments. In this work, features from the 3D gait kinematics, spatio temporal parameters (Set 1) and joint angles (Set 2), of an inertial sensor (IMU) system are proposed as an input for a support vector machine (SVM) model, to differentiate impaired and non-impaired gait. The features were divided into two subsets. The IMU-based features were validated against an optical motion capture (OMC) system by means of 20 patients after THA and a healthy control group of 24 subjects. Then the SVM model was trained on both subsets. The validation of the IMU system-based kinematic features revealed root mean squared errors in the joint kinematics from 0.24° to 1.25°. The validity of the spatio-temporal gait parameters (STP) revealed a similarly high accuracy. The SVM models based on IMU data showed an accuracy of 87.2% (Set 1) and 97.0% (Set 2). The current work presents valid IMU-based features, employed in an SVM model for the classification of the gait of patients after THA and a healthy control. The study reveals that the features of Set 2 are more significant concerning the classification problem. The present IMU system proves its potential to provide accurate features for the incorporation in a mobile gait-feedback system for patients after THA.

According to current estimates, the number of people needing care will double in the next 40 years. It is expected that between 130,000 and 190,000 additional nurses will be needed by 2030 in Germany. Physical and psychological burdens associated with nursing in long-term care facilities can develop into serious health risk factors and significantly impact occupational factors such as absenteeism, especially when linked to difficult working conditions. However, demands and resources specific to the nursing profession have not been analyzed extensively to preserve and promote nurses' workability and health adequately. Our study aimed to examine the extent to which perceived health among geriatric nursing staff in Germany is predicted by personal resources, job demands, and job resources. In addition, we analyzed the impact of different behavior and experience patterns on these relationships. An observational study was conducted between August 2018 and February 2020 in 48 nursing home facilities with 854 staff members in Germany as part of the project 'PROCARE - Prevention and occupational health in long-term care'. The survey contained instruments that measure workplace exposure, musculoskeletal complaints, physical and mental well-being, chronic stress, and work-related behavior and experience patterns. In addition, health-related information on physical activity and nutrition was collected. Data were analyzed using structural equation modeling. The combined physical and mental workload for geriatric nurses is very high, with 75 % showing chronic stress. In the overall model, job and personal resources have a stronger association with mental health than physical health, while job demands have an equal impact on mental and physical health. Coping behavior also plays an important key role that should be assessed and considered. A behavior and experience risk pattern (health-endangering) is more strongly associated with a lower health status than a health-promoting behavior pattern. Results of the multigroup test showed that work-related behavior and experience patterns significantly moderate the relationship between physical health and mental health (χ² = 392/p ≤ .001/df = 256/RMSEA = 0.028/CFI = 0.958/TLI = 0.931). Only 43 % show a health-friendly coping pattern. Our findings underline the importance of holistic health promotion, which not only aims at changes at the behavioral level and the development of coping strategies but also takes on the task of reducing the workload and including measures to improve the working climate. DRKS.de (DRKS00015241); August 9, 2018. Healthier coping patterns can benefit geriatric nurses' health. However, this is not a substitute for improving working conditions.

Background: Interdependencies of health, fitness, cognition, and emotion can promote or inhibit mobility. This study aimed to analyse pathways and interactions between individual subjective and objective physical performance, cognition, and emotions with activities of daily living (ADLs) as mobility indicators in multimorbid nursing home residents. Methods: The study included n = 448 (77.1% females, age = 84.1 ± 7.8 years) nursing home residents. To describe the participant's demographics, frailty, number of falls, and participating institutions' socioeconomic status (SES) were assessed. ADLs were measured with the Barthel Index (BI; dependent variable). Independent variables included objective physical performance, subjective physical performance, cognition, and emotions. A structural equation model (SEM) with maximum likelihood estimation was conducted with AMOS. Direct and indirect effects were estimated using standardized coefficients (significance level of 0.05). Results: Indices showed (Chi²(148) = 217, PCMIN/DF = 1.47; p < .001; Comparative Fit Index = .940; Tucker Lewes Index = .902, RMSEA = .033) that the model fitted the data adequately. While there was no direct association between emotions, subjective physical performance, and ADLs, objective physical performance and cognition predicted higher ADLs (p < .01). Emotions had a strong relationship with subjective physical performance, and cognition had a moderate relationship with objective physical performance. Discussion and conclusion: Objective performance and cognition predicted higher functional status, as expressed by higher BI scores. ADLs, such as mobility, dressing, or handling tasks, require motor and cognitive performance. Subjective performance is an important predictor of ADLs and is only partly explained by objective performance, but to a large extent also by emotions. Therefore, future interventions for nursing home residents should take a holistic approach that focuses not only on promoting objective physical and cognitive performance but also on emotions and perceived physical performance. Trial registration: Trial registration number: DRKS00014957.

Background and aims: One reason for the controversial discussion of whether the dual task (DT) walking paradigm has an added value for diagnosis in clinical conditions might be the use of different gait measurement systems. Therefore, the purpose was 1) to detect DT effects of central gait parameters obtained from five different gait analysis devices in young and old adults, 2) to assess the consistency of the measurement systems, and 3) to determine if the absolut and proportional DT costs (DTC) are greater than the system-measurement error under ST. Methods: Twelve old (72.2 ± 7.9y) and 14 young adults (28.3 ± 6.2y) walked a 14.7-m distance under ST and DT at a self-selected gait velocity. Interrater reliability, precision of the measurement and sensitivity to change were calculated under ST and DT. Results: An age effect was observed in almost all gait parameters for the ST condition. For DT only differences for stride length (p < .029, ɳ²_p = .239) as well as single and double limb support (p = .036, ɳ²_p = .227; p = .034, ɳ²_p = .218) remained. The measurement systems showed a lower absolute agreement compared to consistency across all systems. Conclusions: When reporting DT effects, the real changes in performance and random measurement errors should always be accounted for. These findings have strong implications for interpreting DT effects.

Zusammenfassung: Ganganalysen sowie Gangtraining stellen in der orthopädischen Rehabilitation wichtige Methoden dar, um nach endoprothetischem Gelenkersatz das Gehen wieder zu erlernen. Mehrere Jahre postoperativ zeigen sich jedoch noch deutliche Defizite im Gangbild. Neueste Trainingsmethoden sollen helfen, die am Ende der Rehabilitation noch defizitären Parameter anzusteuern und das Gehen wieder richtig zu erlernen.