Biomedical subjects

J A Engels

Publications and source records attributed to J A Engels.

14 recordsLinked to original sources

PubMed2001

In situ complement activation by polyethylene wear debris.

A frequent long-term complication of total joint arthroplasty is aseptic loosening, the end result of wear debris accumulation, synovitis, and osteolysis about the implant-bone or cement-bone interface. Complement, an effector system in plasma, synovial fluid, and tissue, has powerful chemotactic, inflammatory, and osteoclast-activating potentials. This study explored the complement-activating ability of polyethylene, a material used in joint implants. In vitro hemolytic assays using sheep red blood cells (E(sh)), human serum, and particulate polyethylene suggested alternative pathway complement activation, as well as polyethylene adsorption of activated complement components. These results were confirmed by enzyme-linked immunosorbent assay (ELISA) quantification of activated complement factors Bb and C3b. In situ double antibody immunoperoxidase staining for factors Bb, C3a, iC3b, and SC5-9 in synovial tissue from revision hip specimens showed localized alternative pathway activation and component adsorption. These results introduce a likely role for complement activation in particle-mediated recruitment, proliferation, and activation of macrophages during early events in osteolysis and implant loosening.

Biocompatible Materials↗

PubMed1998

The effects of an ergonomic-educational course. Postural load, perceived physical exertion, and biomechanical errors in nursing.

OBJECTIVES: To evaluate the results of an ergonomic-educational course for nurses we assessed the number and percentage of harmful postures and of ergonomic and biomechanical errors made before and after the course. We also studied the perceived physical exertion. MEANS AND METHODS: In all, 12 nurses who had participated in the course (trainees) and 12 who had not (controls) were recorded on video while performing standardized nursing tasks. The wards from which the two groups of nurses came were comparable, as were the patient populations. The nurses were also comparable in some personal characteristics. The tasks they performed included washing, lifting, and repositioning a patient as well as certain tasks other than patient handling. Video recordings were made once before (1-2 weeks) and twice after the course (after 3 months and after 15 months). The harmful postures, the errors made, and the ratings of perceived exertion were measured by means of the Ovako Working-posture Analysis System (OWAS), a checklist, and Borg scores, respectively. RESULTS: When the first and last measurements of all the above tasks taken as a whole were analyzed the trainees showed a significant improvement in the number and percentage of harmful postures and errors, whereas the controls did not. The same could be concluded for lifting alone. After the course the new work routine did not appear to have caused any extra perceived physical exertion. CONCLUSION: It can be concluded that the course was successful, although it should be carefully investigated as to whether nurses remain capable of working safely in daily practice. The work pressure that nurses experience during their normal duties could prevent them from working safely during everyday work.

Adult↗

PubMed1998

A LISREL analysis of work-related risk factors and health complaints in the nursing profession.

OBJECTIVES: To fit a model which describes the complex interaction between various work-related factors and both musculoskeletal and psychosomatic complaints of nurses simultaneously and to compare the results with those of two LISREL models, in which the health outcome variables are analyzed separately in terms of their correlation with the same set of work-related factors. MATERIALS AND METHODS: Nurses (n=718) working in four Dutch nursing homes completed a questionnaire about work-related factors and musculoskeletal and psychosomatic complaints (response 81%). LISREL was used to describe and analyse the models. RESULTS: The full model had a reasonable overall fit. The strongest (and statistically significant) correlations were found between work postures and musculoskeletal complaints and between psychosocial work demands and psychosomatic complaints. In the two single models, health outcomes showed statistically significant correlations with the same work-related factors as they did in the full model. The full model could be slightly improved when the variable somatized complaints (e.g., dizzyness, headache) was related both to musculoskeletal complaints and to psychosomatic complaints. CONCLUSIONS: Although a model that simultaneously describes more dependent variables appears to provide a better approximation of the complexity of the actual relationship between work-related factors and health effects, the models in which only one health outcome is studied seem to give a proper description of the data at hand. This is an important finding because these single health outcome models resemble the usual analysis strategy by means of standard regression analysis. The adapted version of the full model suggests that musculoskeletal complaints of nurses can partly be understood as non-specific health complaints.

Adult↗

PubMed1998

A simple method to evaluate the reliability of OWAS observations.

Slides showing nurses in different working postures were used to determine the reliability of OWAS observations. Each slide could be looked at for 3 seconds, while a new slide was shown every 30 seconds to resemble the normal practice of observation. Two observers twice scored a series of slides, some of them being identical at both viewings. To reduce effects of recall there was a time interval of 4 weeks or more between the two viewings and the slides were in a different order the second time. Different series were used to evaluate inter- and intra-observer reliability. The OWAS scores of corresponding slides were compared. In almost all comparisons percentages of agreement over 85% and kappa's over 0.6 were found, which is considered as good agreement. The procedure described seems to be a useful and simple technique to determine such reliability.

Humans↗

PubMed1997

Evaluation of the effects of an ergonomic-educational programme. The assessment of "ergonomic errors" made during the performance of nursing tasks.

OBJECTIVES: The objectives of this study were (i) To establish whether it is possible to assess by means of a check-list in a reliable way errors which violated biomechanical and ergonomical principles during nursing tasks, and (ii) to study the effectiveness of an ergonomic-educational course by using this check-list. MATERIALS AND METHODS: Trainees (n = 12) and a control group of nurses (n = 12) who did not attend the course, performed three nursing activities at three points in time under standardized conditions; once before and twice after the course had ended. Their performances were recorded on video. A check-list was developed to assess the number of ergonomic errors made during the test performances. Two observers completed the check-lists after having watched five videotapes, and one of them did this for a second time 3 weeks later, in order to assess inter- and intra-observer reliability. In addition the tapes of all nurses were scored and analysed on differences in the performance of the two groups at the three points in time. Percentage of agreement and kappa (kappa) was used to express inter- and intra-observer reliability. Student's t-test was used to analyse the differences in mean percentages of errors. RESULTS: The inter- and intra-observer reliability were 92% with kappa of 0.84 and 93% with kappa of 0.86, respectively. Further results showed that the mean percentages of errors made by the control group remained the same at the three measurement times. However, in the trainee group a significant decrease in errors was found. The trainees made fewer errors at all three points in time than the controls did. CONCLUSION: It appears feasible to create a check-list to assess ergonomic errors in a reliable way. Trainees make fewer errors after an ergonomic-educational course. It is necessary, however to evaluate whether trained nurses work more safely in their daily duties than during the study.

Adult↗

PubMed1996

Work related risk factors for musculoskeletal complaints in the nursing profession: results of a questionnaire survey.

OBJECTIVES: To determine the prevalence of musculoskeletal complaints of the back, arms or neck, and legs among nurses, and to investigate the relation between these complaints and various work related and personal variables. METHODS: A questionnaire survey was carried out in four nursing homes in The Netherlands. RESULTS: The response was 95% and resulted in 846 completed questionnaires. It was found that a large proportion of the subjects regularly had back complaints (36%) but also had arm or neck (30%) and leg complaints (16%). Almost all respondents (89%) considered nursing work as physically strenuous. Most of them complained of working under time pressure (69%), increased work pressure (70%), and having no opportunity to take a break from the work (70%). The physical variables which seem to trouble the subjects most were lifting (65%), working in awkward postures (47%), and stooping (34%). Moreover, 53% of the subjects responded that the ergonomic lay out of the ward was disagreeable. Most of the work related variables under study seemed to be associated with musculoskeletal complaints. For all types of complaints the strongest associations were found with having to lift heavy loads. Apart from physical stress various aspects of work pressure showed strong associations with the occurrence of musculoskeletal complaints. The variables on the ergonomy of the ward showed less clear associations with musculoskeletal complaints than were found for physical stress and work pressure. CONCLUSIONS: From these results it may be concluded that future research of health risks of nursing work should have a wider focus than the relation between physical workload and low back pain.

Adult↗

PubMed1994

An OWAS-based analysis of nurses' working postures.

The working postures of Dutch nurses (n = 18) in an orthopaedic ward and a urology ward were observed using the Ovako Working posture Analysis System (OWAS). During observation, both working postures and activities were recorded. A specially developed computer program was used for data analysis. By means of this program, it was possible to calculate the working posture load for each activity and the contribution of a specific activity to the total working posture load. This study shows that some activities of the nurses in both wards were performed with poor working postures. In the orthopaedic (resp. urology) ward two (resp. one) out of 19 observed postures of parts of the body were classified as Action Category 2. Moreover, 20% (resp. 16%) of the so-called typical working postures was classified in Action Category 2. This suggests, that in both wards working postures that are slightly harmful to the musculoskeletal system, occur during a substantial part of the working day. Differences between both wards with respect to working posture load and time expenditure were determined. Activities causing the workload to fall into OWAS higher Action Categories were identified. The data show that poor working postures in the nursing profession not only occur during patient handling activities but also during tasks like 'administration'. Focusing on patient-handling (i.e., lifting patients) in order to determine the load on the musculoskeletal system would therefore lead to an underestimation of the total working posture load of nurses.

Adult↗

PubMed1994

Physical work load and its assessment among the nursing staff in nursing homes.

A study was conducted to investigate the physical work load and the prevalence of musculoskeletal complaints of nurses in nursing homes. Thirty-six female subjects selected from three nursing homes in the Netherlands participated in an observational study. In addition, the total nursing staff (n = 668) was invited to take part in a questionnaire survey (response was 94%). It was noticed that almost 60% of the observed time was spent on nonpatient-related activities. Moreover, activities alternated rapidly and seldom lasted longer than 4 minutes on average. Twenty percent of the observed time was spent in "poor" work postures as defined by the Ovako Working Posture Analyzing System (Action Category 2 to 4). Activities contributing most to these poor work postures were patient care and household and preliminary tasks. Perceived exertion as scored on the Borg-CR10 scale was highest during patient-related activities. This holds also for a relative increase of heart rate. Questionnaire results showed prevalences of 41%, 35%, and 20% respectively, for back, arm/neck, and leg complaints. From this study it can be concluded that not only patient-related activities should be taken into consideration for the improvement of work postures and other potential strenuous aspects of nursing work. Household and preliminary tasks, ergonomic layout of the ward, and work pressure also deserve attention.

Adult↗

PubMed1991

The "fallen lung with absent hilum" signs of complete bronchial transection.

A 19-year-old pedestrian who was the victim of a motor vehicle accident had a left pneumothorax with a large air leak. Despite a well-placed chest tube, a chest radiograph showed that the left lung had fallen down and away from the mediastinum and that no hilar structures were visible. This "fallen lung with an absent hilum" is considered virtually diagnostic of complete mainstem bronchus transection.

Adult↗

PubMed1972