Biomechanical analysis of the effect of changing patient-handling technique

Effectiveness of Safe Patient Handling Equipment and Techniques: A Review of Biomechanical Studies

OBJECTIVE

This review aimed to evaluate all studies that have evaluated the biomechanical effects when using assistive devices.

INTRODUCTION

The physical demands of patient handling activities are well known. One safety strategy for the reduction of the physical risks is use of assistive devices.

METHOD

The search process identified articles published in English-speaking journals through Google Scholar, Medline, and ISI Web of Science. The included 56 studies contained a biomechanical assessment of a patient handling activity with assistive devices.

RESULTS

The biomechanical effects included four groups: changes in body posture (spinal, other joints), subjective assessment (force, effort, discomfort), measured force (hand force, ground reaction force, spine force, joint torque), and physiological measures. The evidence showed caregivers benefited from using lift hoists, air-assisted devices, and to a lesser extent friction reducing devices for lateral transfers and repositioning, while floor and ceiling lifts were most effective for patient transfers. Some gaps were noted in the evidence and other handling tasks such as sit-to-stand, turning patient in bed, limb lifting, and repositioning and some more high hazard activities like supporting people with limited balance and those that fall need to be investigated with respect to biomechanical outcomes.

CONCLUSION

There is a growing level of biomechanical evidence to support the use of assistive devices for many patient-handling tasks, but the benefits of equipment use in some transfers remain uninvestigated.

PRACTICAL APPLICATION

Evidence indicates the best way to lift patients safely is with floor or ceiling lifts, and air-assisted devices for lateral and repositioning tasks.

Torso Kinematics in Human Rolling Do Not Change When Upper Extremity Motion Is Constrained

Human rolling, as turning in bed, is a fundamental activity of daily living. A quantitative analysis of rolling could help identify the neuromusculoskeletal disorders that prohibit rolling and develop interventions for individuals who cannot roll. This study sought to determine whether crossing the arms over the chest would alter fundamental coordination patterns when rolling. Kinematic data were collected from 24 subjects as they rolled with and without their arms crossed over their chest. Crossing the arms decreased the mean peak angular velocities of the shoulders (p = .001) and pelvis (p = .013) and influenced the mean duration of the roll (p = .057). There were no fundamental differences in shoulder and pelvis coordination when rolling with the arms crossed over the chest, implying that the arms may not have a major role in rolling.

Effect of Repositioning Aids and Patient Weight on Biomechanical Stresses When Repositioning Patients in Bed

OBJECTIVE

The aim of the study was to estimate the risk of injury when repositioning patients of different weight with commonly used repositioning aids.

BACKGROUND

Repositioning dependent patients in bed is the most common type of patient handling activity and is associated with high rates of musculoskeletal disorders in healthcare workers. Several studies have evaluated repositioning aids, but typically for a single patient weight and often without estimating risk of injury based on biomechanical analysis.

METHOD

Ten nurses performed four repositioning activities on three participants (50, 77, 141 kg) using three repositioning aids (pair of friction-reducing sheets [FRS], turn and position glide sheet, air-assisted transfer device) and a draw sheet. Motion capture, hand forces, and ground reaction forces were recorded. Spine loading was estimated using a dynamic biomechanical model.

RESULTS

Hand forces and spine compression exceeded recommended limits for most patient weights and repositioning tasks with the draw sheet. FRS and glide sheet reduced these loads but still exceeded recommended limits for all but the 50-kg patient. Only the air-assisted transfer device reduced forces to accepted levels for all patient weights. Physical stresses were relatively low when turning patients.

CONCLUSION

Most repositioning aids are insufficient to properly mitigate risk of musculoskeletal injury in healthcare workers. Only the air-assisted transfer device was sufficient to adequately mitigate the risk of injury when moving patients of average or above-average weight.

APPLICATION

To safely move dependent patients, a robust solution requires mechanical lifts and may utilize air-assisted transfer devices for patient transfers.

Biomechanical comparison between manual and motorless device assisted patient handling: sitting to and from standing position

Although lots of assistive devices have been studied to fight against caregivers' work-related musculoskeletal disorders, stand-and-turn devices effects on biomechanical constraints are still unknown. The aim of this study is to provide and compare quantitative data on loads in the low back area resulting from the use of a motorless stand-and-turn device and from manual patient handling. Nine caregivers participated to motion capture and ground reaction forces measurement sessions of three cases of handling: manual handling with one caregiver, manual handling with two caregivers, motorless device assisted handling. Forces and torques at the L5/S1 joint were computed through Inverse Dynamics process. Motorless device assisted handling required the smallest loads whereas manual handling with one caregiver required the biggest loads, the latter being in some cases twice as big as the former. Caregivers should use a stand-and-turn device when handling a patient from sitting/standing to standing/sitting position whenever it is possible.

Optimal foot-position of caregiver based on muscle activity of lower back and lower limb while providing sit-to-stand support

[Purpose] In caregivers, low load posture is necessary to prevent lower back pain during patient handling activities such as sit-to-stand support. This study focused on the foot-position of caregivers as an adjustable and useful parameter. A wide stance decreases the stress on the lumbar vertebra. However, this foot-position increases loading of the spinae erector muscles. The aim of this study was to investigate the relationship of anterior-posterior and lateral-medial distances between feet and activity of the spinae erector muscles to determine the optimal foot-position for reducing stress on the lumbar vertebra without increasing spinae erector muscle load. [Participants and Methods] Five young male participants were asked to provide sit-to-stand support 10 times using nine normalized foot-positions with different anterior-posterior and lateral-medial distances. Surface electromyograms of the erector spinae and lower limb muscles were measured during sit-to-stand support. [Results] The results showed that the optimal foot-position (anterior-posterior 55%, lateral-medial 20% of body height) increased muscle activity within the lower limb muscles compared with the lower back muscles and did not increase loads on the erector spinae muscle. [Conclusion] Optimizing foot-position can reduce stress on the lumbar vertebra without increasing load on the spinae erector muscles.

Air-assisted devices reduce biomechanical loading in the low back and upper extremities during patient turning tasks

This laboratory study evaluated different assistive devices for reducing biomechanical loading during patient turning tasks. Twenty caregivers (18 females and 2 males) performed standardized patient turning tasks with two simulated patients (body mass: 74 kg and 102 kg). The turning tasks were performed in two turning directions (toward vs. away relative to caregivers) using five device conditions: draw sheet, friction-reducing turning sheet, air-assisted transfer device, air-assisted turning device, and no assistive device. Low back and upper extremity muscle activity, trunk and shoulder postures, low back moment, and self-reported usability ratings were evaluated. While all assistive devices reduced trunk flexion, both air-assisted transfer and turning devices reduced the trunk flexion (p's < 0.001) and muscle activity (p's < 0.001) in the erector spinae and triceps compared to no assistive device condition. These results suggest that the air-assisted devices have potential as an effective intervention to considerably reduce physical risk factors associated with caregivers' musculoskeletal disorders in low back and upper extremities.

Intervertebral Disc Disease of the Lumbar Spine in Health Personnel with Occupational Exposure to Patient Handling-A Systematic Literature Review and Meta-Analysis

Lifting or carrying loads or working while the trunk is in a bent position are well established risk factors for the development of disc disease of the lumbar spine (LDD). Patient handling is associated with certain hazardous activities, which can result in exposure to heavy loads and high pressure for the discs of the lumbar spine of the nurses performing these tasks. The purpose of this review was to examine the occurrence of work-related LDD among health personnel (HP) with occupational exposure to patient handling activities in comparison to un-exposed workers. A systematic literature search was conducted using the following databases: PubMed, CINAHL, Scopus, and Web of Science. A meta-analysis of odds ratios (OR) was conducted by stratifying for various factors. Five studies reported a higher prevalence for LDD among nurses and geriatric nurses (11.3–96.3%) compared to all controls (3.78–76.47%). Results of the meta-analysis showed a significantly increased OR for LDD among HP compared to all controls (OR 2.45; 95% confidence interval (CI) 1.41, 4.26). In particular, the results of this review suggest that nurses have a higher probability of developing disc herniation than office workers.

Can the Use of Turn-Assist Surfaces Reduce the Physical Burden on Caregivers When Performing Patient Turning?

OBJECTIVE

To quantify differences in physical workload afforded by turn-assist surfaces relative to manual patient turns, and between nursing caregivers (turn-away vs. turn-toward) while performing partnered patient turning.

BACKGROUND

Nurse caregivers experience an increased risk of musculoskeletal injuries at the back or shoulders when performing patient-handling activities. Use of turn-assist surfaces can reduce the physical burden and risk on caregivers.

METHOD

Whole-body motion capture and hand force measures were collected from 25 caregivers (17 female) while performing partnered manual and technology-facilitated turns. Shoulder and low back angles and L4/L5 joint contact forces were calculated at the instant of peak hand force application for both caregivers.

RESULTS

Hand force requirements for the turn-away caregiver were 93% of the estimated maximum acceptable force when performing a manual turn. Use of a turn-assist surface eliminated hand forces required to initiate the patient turn for the turn-away caregiver, where their role was reduced to inserting appropriate wedging behind the patient once the facilitated turn was complete. This reduced shoulder moments by 21.3 Nm for the turn-away caregiver, a reduction in exposure from 70% of maximum shoulder strength capacity to 15%. Spine compression exposures were reduced by 302.1 N for the turn-toward caregiver when using a turn-assist surface.

CONCLUSION

Use of a turn-assist surface reduced peak hand force and shoulder-related exposures for turning away and reduced spine-related exposures for turning toward.

APPLICATION

Turn-assist devices should be recommended to decrease the risk of musculoskeletal disorder hazards for both caregivers when performing a partnered patient turn.

Relationship between surface electromyography of the spinae erector muscles and subjectively adjusted step length in the supporting standing-up motion

[Purpose] Caregivers experience low back pain owing to frequent patient handling motions such as supporting the body while standing up. To prevent low back pain in caregivers, low load posture while engaging in patient handling motions is required. We determined the relationship between surface electromyography of the erector spinae muscles and subjective step length as "long" and "short" during the supporting standing-up motions of caregivers. [Participants and Methods] Ten young male participants were asked to perform supporting standing-up motion 10 times using two-step lengths comprised of subjective long and short steps. During supporting standing-up motion, we measured surface electromyograms of the erector spinae muscles and calculated the integral electromyographic values. [Results] The subjective long/short-step length normalized by body height did not differ across the participants. In addition, the subjective long-step length was longer than the subjective short-step length in all the participants. Integral electromyographic values for both the left and right erector spinae muscles in the short-step length were significantly lower than those in the long-step length when the data obtained from all the participants were used. [Conclusion] We considered that the load of the erector spinae muscle will be reduced if the short-step instead of the long-step instruction is given. In the future, instructions based on the subjective step-length variation in caregivers must be considered.

Sliding Sheet Use in Nursing Practice: An Intervention Study

Background: Previous studies have discovered that the utilization of sliding sheets in patient care is a valuable technique for repositioning bedridden patients compared with traditional cotton sheets or carriers. Our aim was to examine the effects of sliding sheet usage on work-related musculoskeletal disorders and disability, perceived workload, burnout, and job satisfaction, among nurses and nursing assistants. Method: This repeated measurement study included 41 female nurses and nursing assistants from three internal medicine departments who provided direct patient care. Participants completed an eight-part questionnaire (demographics, Neck Disability Index, Quick Disability of the Arms, Shoulder and Hand Questionnaire, Modified Oswestry Low Back Pain Disability Questionnaire, BackAche Disability Index workload, burnout, and job satisfaction) 4 times during the study period: 3 months prior to the intervention, on the first day of the intervention, and 3 and 6 months after commencement of the intervention. Findings: After 3 and 6 months of sliding sheet usage, pain and disability decreased in the neck ( p < .001); arms, shoulders, hands ( p = .041); and lower back ( p < .001), with an increase in job satisfaction ( p < .001). Discussion/Application to Practice: The findings of our study indicate a clear influence of reducing work-related musculoskeletal pain and disability while increasing job satisfaction when sliding sheets are introduced into nursing practice. Occupational health nurses in health care should consider this type of low-cost intervention as a method for reducing musculoskeletal injury among direct patient care providers.

MUSCULOSKELETAL SIMULATION OF THE RELATIONSHIP BETWEEN FOOT POSITION AND STRESS OF THE L4–L5 JOINT IN SUPPORTING STANDING-UP MOTION TO PREVENT LOW BACK PAIN AMONG CAREGIVERS

Most caregivers have low back pain which results from frequent care activities such as assistance motion that supports transfer and standing-up. Various parameters are associated with the caregiver’s lumbar load. In this study, we focus on the foot position of the caregiver as one of the subjective adjustable parameters. This study aimed to analyze the relationship between foot position and stresses of the L4–L5 joint as lumbar load during supporting standing-up via musculoskeletal simulation. The musculoskeletal model was tasked with simulating supported standing-up motions based on a specific pelvic position and angular variation of each joint. The anterior foot (left foot) was fixed, and the posterior foot (right foot) was moved to three backward positions and three rightward positions, thus obtaining nine posterior foot positions. Compressive, anteroposterior shear, and lateral shear stresses of the L4–L5 joint were compared for nine foot positions. The results showed that as the anteroposterior distance and lateral widths between both feet increased, the average value of compressive/shear stress of the L4–L5 joint during motions decreased. From our findings, we hypothesized that the foot position may reduce the lumbar load and prevent low back pain.

Manual Handling in Aged Care: Impact of Environment-related Interventions on Mobility

The manual handling of people (MHP) is known to be associated with high incidence of musculoskeletal disorders for aged care staff. Environment-related MHP interventions, such as appropriate seated heights to aid sit-to-stand transfers, can reduce staff injury while improving the patient's mobility. Promoting patient mobility within the manual handling interaction is an endorsed MHP risk control intervention strategy. This article provides a narrative review of the types of MHP environmental controls that can improve mobility, as well as the extent to which these environmental controls are considered in MHP risk management and assessment tools. Although a range of possible environmental interventions exist, current tools only consider these in a limited manner. Development of an assessment tool that more comprehensively covers environmental strategies in MHP risk management could help reduce staff injury and improve resident mobility through auditing existing practices and guiding the design of new and refurbished aged care facilities.

Patient Transfers and Risk of Back Injury: Protocol for a Prospective Cohort Study With Technical Measurements of Exposure

Background

More than one third of nurses experience musculoskeletal pain several times during a normal work week. Consistent use of assistive devices during patient transfers is associated with a lower risk of occupational back injuries and low back pain (LBP). While uncertainties exist regarding which type of assistive devices most efficiently prevent LBP, exposure assessments using technological advancements allow for quantification of muscle load and body positions during common work tasks.

Objective

The main objectives of this study are (1) to quantify low back and neck/shoulder muscle load in Danish nurses during patient transfers performed with different types of assistive devices, and (2) to combine the exposure profile for each type of assistive device with fortnightly questionnaires to identify the importance of muscle load (intensity and frequency of transfers) and body position (degree of back inclination and frequency) on LBP intensity and risk of back injury during a patient transfer.

Methods

A combination of technical measurements (n=50) and a prospective study design (n=2000) will be applied on a cohort of female nurses in Danish hospitals. The technical measurements will be comprised of surface electromyography and accelerometers, with the aim of quantifying muscle load and body positions during various patient transfers, including different types of assistive devices throughout a workday. The study will thereby gather measurements during real-life working conditions. The prospective cohort study will consist of questionnaires at baseline and 1-year follow-up, as well as follow-up via email every other week for one year on questions regarding the frequency of patient transfers, use of assistive devices, intensity of LBP, and back injuries related to patient transfers. The objective measurements on muscle load and body positions during patient handlings will be applied to the fortnightly replies regarding frequency of patient transfer and use of different assistive devices, in order to identify risk factors for back injuries related to patient transfers and intensity of LBP.

Results

Data collection is scheduled to commence during the winter of 2017.

Conclusions

The design of this study is novel in its combination of technical measurements applied on a prospective cohort, and the results will provide important information about which assistive devices are associated with intensity of LBP and risk of back injury related to patient transfers. Furthermore, this study will shed light on the dose-response relationship between intensity, duration, and frequency of patient transfers and the intensity of LPB in Danish nurses, and will thereby help to guide and improve electronic health practices among this population.

Validity and reliability of the HEMPA method for patient handling assessment

Specific methods currently exist to assess occupational hazards resulting from patient handling in the healthcare sector, according to ISO/TR 12296. They are all similar in nature, but with a different analysis perspective; for that reason a comparison of the most relevant methods was performed in a previous research. As a result, a basis of a new tool that integrates the complementary aspects of those methods was proposed. To verify the validity and reliability of that method, a study within a hospital setting was carried out in five medical and surgical units of a public health institution. Based on the obtained results, the analysed method (called HEMPA) proved to be valid and reliable. Also, this method reflects a positive correlation between risk and damage and correctly quantifies risks regarding patient's dependence.

A multi-component patient-handling intervention improves attitudes and behaviors for safe patient handling and reduces aggression experienced by nursing staff: A controlled before-after study

This study evaluated an intervention for patient-handling equipment aimed to improve nursing staffs' use of patient handling equipment and improve their general health, reduce musculoskeletal problems, aggressive episodes, days of absence and work-related accidents. As a controlled before-after study, questionnaire data were collected at baseline and 12-month follow-up among nursing staff at intervention and control wards at two hospitals. At 12-month follow-up, the intervention group had more positive attitudes towards patient-handling equipment and increased use of specific patient-handling equipment. In addition, a lower proportion of nursing staff in the intervention group had experienced physically aggressive episodes. No significant change was observed in general health status, musculoskeletal problems, days of absence or work-related accidents. The intervention resulted in more positive attitudes and behaviours for safe patient-handling and less physically aggressive episodes. However, this did not translate into improved health of the staff during the 12-month study period.

Biomechanical Evaluation of a Bed Feature to Assist in Turning and Laterally Repositioning Patients

OBJECTIVE

This study investigated the effects of hospital bed features on the biomechanical stresses experienced by nurses when turning and laterally repositioning patients. Turn Assist, a common feature in ICU beds that helps to rotate patients, and side rail orientation were evaluated.

BACKGROUND

Manual patient handling is a risk factor for musculoskeletal injury, and turning patients is one of the most common patient handling activities. No known studies have evaluated bed attributes such as the Turn Assist feature and side rail orientation that may affect the stresses experienced by the nurse.

METHOD

Nine female nurses laterally repositioned and turned a 63-kg and 123-kg subject on an ICU bed while motion capture, ground reaction forces, and hand force data were recorded. Loading of the spine and shoulder was modeled using 3D Static Strength Prediction Program (3DSSPP).

RESULTS

Spine compression and shear forces did not exceed recommended limits when turning or laterally repositioning. However, the mean pull forces required to manually laterally reposition even the 63-kg subject was 340 Newtons, more than 50% greater than limits established in psychophysical testing. Turn Assist considerably reduced spine loading and pull forces for both turning and laterally repositioning. Lowering side rails reduced spinal compression by 11% when turning patients.

CONCLUSION

Laterally repositioning patients as part of turning may pose an injury risk to caregivers. Turn Assist reduces physical loading on nurses when turning and repositioning patients.

APPLICATION

Caregivers should consider using Turn Assist and other aids such as mechanical lifts or sliding sheets especially when turning patients requires lateral repositioning.

Ergonomic assessment for the task of repairing computers in a manufacturing company: A case study

BACKGROUND

Manufacturing industry workers who repair computers may be exposed to ergonomic risk factors.

OBJECTIVES

This project analyzes the tasks involved in the computer repair process to (1) find the risk level for musculoskeletal disorders (MSDs) and (2) propose ergonomic interventions to address any ergonomic issues.

METHODS

Work procedures and main body postures were video recorded and analyzed using task analysis, the Rapid Entire Body Assessment (REBA) postural method, and biomechanical analysis.

RESULTS

High risk for MSDs was found on every subtask using REBA. Although biomechanical analysis found an acceptable mass center displacement during tasks, a hazardous level of compression on the lower back during computer's transportation was detected.

CONCLUSIONS

This assessment found ergonomic risks mainly in the trunk, arm/forearm, and legs; the neck and hand/wrist were also compromised. Opportunities for ergonomic analyses and interventions in the design and execution of computer repair tasks are discussed.

Development of a motion capturing and load analyzing system for caregivers aiding a patient to sit up in bed

This research was carried out to analyze the actions of caregivers when aiding a patient to sit up in bed. The new system showed that three dimensional analysis could be performed even on points on the subjects' bodies that were hidden from view. We also developed a method to estimate the load on the lumbar region of caregivers based on the kinetic analysis of the human body. Using this system we were able to evaluate the performance of both lay and professional caregivers. We found a clear difference between the performances of the two types of caregivers, and noted that the professional adopted a posture that was safe and did not stress the lumbar vertebrae, whereas the layperson tended to adopt an unsafe posture.

Lifting strategies of expert and novice workers during a repetitive palletizing task

Thirty manual material handlers (15 experts and 15 novices) were invited to perform series of box transfers under conditions similar to those of large distribution centers. The objective of the present study was to verify whether multiple box transfers leading to fatigue would also lead to differences between expert and novice workers in joint motions and in back loading variables (L5/S1 moments). The task consisted in transferring 24 15-kg boxes from one pallet to another (4 layers of boxes; 6 boxes/layer: 3 in the front row, 3 in the back) at a self-determined pace and then at an imposed pace of 9 lifts/min for a total of 240 lifts. The underlying idea was to set a challenging task that would force the experts to use their skills. Full-body 3D kinematic data were collected as well as external foot forces. A dynamic 3D linked segment model was used to estimate the net moments at L5/S1. The results clearly show that the experts bent their lumbar spine less (10° less) and were closer (4 cm) to the box than novice workers. Knee flexions were similar in both groups except when the box was lifted from ground level (expert ≈ 71°, novice ≈ 48°). The peak resultant moment was not statistically different (expert = 168 Nm, novice = 184 Nm) although experts had lower values on average than novices when lifting heights (and deposit heights) of the boxes increased. Therefore, experts differed from novice workers mostly in the posture-related variables. These differences are especially important to consider when the box is located on the ground, as the back posture and back loading are then at their greatest magnitude and could have a major impact on the distribution of internal forces on the spine.

Safe patient handling education in Nepal: a Canadian perspective in creating and conducting training in a developing country

BACKGROUND

Safe patient handling (SPH) and positioning is a worldwide health care issue in both developed and developing countries. It is important for all caregivers and patients but especially for palliative care and oncology patients. While there is a wide breadth of curriculum available in developed countries, little information is available about how to teach SPH and positioning in a developing country where resources are very limited.

OBJECTIVE/METHODOLOGY

This article describes the process and recommendations used by a Canadian multidisciplinary health professional team in developing SPH curriculums for palliative care communities in Nepal. Educational materials were developed to teach SPH to a group of health care professionals at a palliative care conference in Bhaktapur, Nepal, in addition to a number of other settings within the Kathmandu Valley area.

RESULTS

Current barriers toward future development of SPH in Nepal are defined and discussed. The SPH curriculums that have been created are provided and specific recommendations are outlined. There is a dearth of research to guide SPH education in developing countries. SPH change requires long-term support and curriculums that are culturally sensitive and contextually appropriate.

Lumbar-load analysis of manual patient-handling activities for biomechanical overload prevention among healthcare workers

Manual patient handling commonly induces high mechanical load on the lower back of healthcare workers. A long-term research project, the 'Third Dortmund Lumbar Load Study' (DOLLY 3), was conducted to investigate the lumbar load of caregivers during handling activities that are considered 'definitely endangering' in the context of worker's compensation procedures. Nine types of handling activities in or at a bed or chair were analysed. Measurement of action forces via specifically developed devices and posture recording by means of optoelectronic marker capturing and video recordings in order to quantify several lumbar-load indicators was previously described in detail. This paper provides the results of laboratory examinations and subsequent biomechanical model calculations focused on lumbar load and the potentials of load reduction by applying biomechanically 'optimized' transfer modes instead of a 'conventional' technique and, for a subgroup of tasks, the supplementary usage of small aids such as a sliding mat or a glide board. Lumbosacral-disc compressive force may vary considerably with respect to the performed task, the mode of execution, and individual performance. For any activity type, highest values were found for conventional performance, lower ones for the improved transfer mode, and the lowest compressive-force values were gathered when small aids were applied. Statistical significance was verified for 13 of these 17 comparisons. Analysing indicators for asymmetric loading shows that lateral-bending and torsional moments of force at the lumbosacral disc may reach high values, which can be reduced considerably by implementing an improved handling mode. When evaluating biomechanical loads with respect to age- and gender-specific work-design limits, none of the analysed tasks, despite execution mode, resulted in an acceptable load range. Therefore, applying a biomechanically adequate handling mode combined with small aids to lower the friction between patient and surfaces is highly recommended, especially to prevent overload in older caregivers.

Long-term efficacy of an ergonomics program that includes patient-handling devices on reducing musculoskeletal injuries to nursing personnel

OBJECTIVE

The aim of this study was to evaluate long-term efficacy of an ergonomics program that included patient-handling devices in six long-term care facilities (LTC) and one chronic care hospital (CCH).

BACKGROUND

Patient handling is recognized as a major source of musculoskeletal disorders (MSDs) among nursing personnel, and several studies have demonstrated effectiveness of patient-handling devices in reducing those MSDs. However, most studies have been conducted in a single facility, for a short period, and/or without a comprehensive ergonomics program.

METHOD

Patient-handling devices along with a comprehensive ergonomics program was implemented in six LTC facilities and one CCH. Pre- and postintervention injury data were collected for 38.9 months (range = 29 to 54 months) and 51.2 months (range = 36 to 60 months), respectively.

RESULTS

Postintervention patient-handling injuries decreased by 59.8% (rate ratio [RR] = 0.36, 95% confidence interval [CI] [0.28, 0.49], p < .001), lost workdays by 86.7% (RR = 0.16, 95% CI [0.13, 0.18], p < .001), modified-duty days by 78.8% (RR = 0.25, 95% CI [0.22, 0.28], p < .001), and workers' compensation costs by 90.6% (RR = 0.12, 95% CI [0.09, 0.15], p < .001). Perceived stresses to low back and shoulders among nursing staff were fairly low. A vast majority of patients found the devices comfortable and safe. Longer transfer times with the use of devices was not an issue.

CONCLUSION

Implementation of patient-handling devices along with a comprehensive program can be effective in reducing MSDs among nursing personnel. Strategies to expand usage of patient-handling devices in most health care settings should be explored.

Two linear regression models predicting cumulative dynamic L5/S1 joint moment during a range of lifting tasks based on static postures

Previous studies have indicated that cumulative L5/S1 joint load is a potential risk factor for low back pain. The assessment of cumulative L5/S1 joint load during a field study is challenging due to the difficulty of continuously monitoring the dynamic joint load. This study proposes two regression models predicting cumulative dynamic L5/S1 joint moment based on the static L5/S1 joint moment of a lifting task at lift-off and set-down and the lift duration. Twelve men performed lifting tasks at varying lifting ranges and asymmetric angles in a laboratory environment. The cumulative L5/S1 joint moment was calculated from continuous dynamic L5/S1 moments as the reference for comparison. The static L5/S1 joint moments at lift-off and set-down were measured for the two regression models. The prediction error of the cumulative L5/S1 joint moment was 21 ± 14 Nm × s (12% of the measured cumulative L5/S1 joint moment) and 14 ± 9 Nm × s (8%) for the first and the second models, respectively. Practitioner Summary: The proposed regression models may provide a practical approach for predicting the cumulative dynamic L5/S1 joint loading of a lifting task for field studies since it requires only the lifting duration and the static moments at the lift-off and/or set-down instants of the lift.

A biomechanical assessment of floor and overhead lifts using one or two caregivers for patient transfers

This study investigated the differences in peak external hand forces and external moments generated at the L5/S1 joint of the low back due to maneuvering loaded floor-based and overhead-mounted patient lifting devices using one and two caregivers. Hand forces and external moments at the L5/S1 joint were estimated from ground reaction forces and motion capture data. Caregivers gave ratings of perceived exertion as well as their opinions regarding overhead vs. floor lifts. Use of overhead lifts resulted in significantly lower back loads than floor lifts. Two caregivers working together with a floor lift did not reduce loads on the primary caregiver compared to the single-caregiver case. In contrast, two-caregiver operation of an overhead lift did result in reduced loads compared to the single-caregiver case. Therefore, overhead lifts should be used whenever possible to reduce the risk of back injury to caregivers. The use of two caregivers does not compensate for the poorer performance of floor lifts.

Characteristic values of the lumbar load of manual patient handling for the application in workers' compensation procedures

Background

The human spine is often exposed to mechanical load in vocational activities especially in combination with lifting, carrying and positioning of heavy objects. This also applies in particular to nursing activities with manual patient handling. In the present study a detailed investigation on the load of the lumbar spine during manual patient handling was performed.

Methods

For a total of 13 presumably endangering activities with transferring a patient, the body movements performed by healthcare workers were recorded and the exerted action forces were determined with regard to magnitude, direction and lateral distribution in the time course with a "measuring bed", a "measuring chair" and a "measuring floor". By the application of biomechanical model calculations the load on the lowest intervertebral disc of the lumbar spine (L5-S1) was determined considering the posture and action force data for every manual patient handling.

Results

The results of the investigations reveal the occurrence of high lumbar load during manual patient handling activities, especially in those cases, where awkward postures of the healthcare worker are combined with high action forces caused by the patient's mass. These findings were compared to suitable issues of corresponding investigations provided in the literature. Furthermore measurement-based characteristic values of lumbar load were derived for the use in statement procedures concerning the disease no. 2108 of the German list of occupational diseases.

Conclusions

To protect healthcare workers from mechanical overload and the risk of developing a disc-related disease, prevention measures should be compiled. Such measures could include the application of "back-fairer" nursing techniques and the use of "technical" and" small aids" to reduce the lumbar load during manual patient handling. Further studies, concerning these aspects, are necessary.

Are low back pain and low physical capacity risk indicators for dropout among recently qualified eldercare workers? A follow-up study

BACKGROUND

A high job turnover and dropout among eldercare workers has led to a significant shortage of qualified manpower in the Danish eldercare sector.

OBJECTIVES

The predictive effect of some non-work-related causes for leaving the eldercare sector 2 years after qualification, physical capacity, duration, and severity of previous low back pain, was investigated.

DESIGN AND SETTING

A 2-year prospective cohort study of all the Danish eldercare workers, who finished their education during 2004 (n = 6347). Questionnaire data from 2004 were followed up by register data on attachment to labour market, educational status, and association to trade from Statistics Denmark in 2006.

METHODS

Data on physical capacity, duration, and severity of low back pain the last 12 months among the female participants were analysed by multinomial logistic regression to estimate odds-ratios for being either in the eldercare sector, in other health- and welfare sectors, in all other sectors, under education, or outside labour market, 2 years after qualification.

RESULTS

Disability due to and duration of low back pain were significant predictors for dropout from the eldercare sector 2 years after qualification. Low physical capacity was not. Data on duration of low back pain suggest a trend towards a dose-response relationship: The longer the duration of low back pain, the higher odds for dropout.

CONCLUSIONS

Low back pain and disability due to low back pain during the last year of education were independent predictors for dropout from the eldercare sector 2 years after qualification. However, low self-rated physical capacity did not predict job dropout or turnover.

Effects of general principles of person transfer techniques on low back joint extension moment

The purpose of this study was to examine the effects of general principles of person transfer techniques specifically on the low back joint extension moment. These effects were examined by the following measurable quantitative parameters: 1) trunk bending angle, 2) knee flexion angle, 3) distance between the centers of gravity (COGs) of the caregiver and patient, representing the distance between the caregiver and patient, and 4) the vertical component of the ground reaction force representing the amount of the weight-bearing load on the caregiver's low back during transfers with and without assistive devices. Twenty students each took the role of caregiver, and one healthy adult simulated a patient. The participants performed three different transfer tasks: without any assistive device, with the patient wearing a low back belt, and with the caregiver using a transfer board. We found that the distance between the COGs and the vertical component of the ground reaction force, but not the trunk bending and knee flexion angles, were the variables that affected the low back joint extension moment. Our results suggest that the general principle of decreasing the distance between COGs is most effective for decreasing the low back joint extension moment during transfers under all conditions.

Effects of educational intervention on joint angles of the trunk and lower extremity and on muscle activities during patient-handling tasks

OBJECTIVE

The objective of this study was to examine the effects of educational intervention on joint angles of the trunk and lower extremity and on muscle activities during patient-handling task.

METHODS

Thirty-two subjects (17 males and 15 females) volunteered for the study. They were classified into three groups: intervention group 1, comprised of first grade physical therapist students; control group, which included first grade occupational therapist students; intervention group 2, which comprised third grade physical therapist students. The educational intervention during the experimental period consisted of: (1) 12 regular classes and short-term clinical practice for the students of intervention group 1; (2) long-term clinical practice, relating to patient-handling task, for the students of intervention group 2. The following experiments were repeated before and after the educational intervention. Each subject was asked to transfer a male (55 kg) from one chair to a second chair (left to right) and then back again to the original chair (right to left). The flexion angles of the trunk, hip and knee joints were quantified by means of the dynamic three-dimensional biomechanical analysis. Muscle activities (% maximum voluntary contraction, %MVC) of biceps brachii, trapezius, rectus femoris and erector spinae muscles were measured using surface electromyography (EMG). The effects of group, gender, measurement time and side on joint angles of trunk and lower extremity, %MVC of four muscle activities and transfer time were assessed.

RESULTS

Although the EMG analysis could not clearly demonstrate any reduction of physical load to the low back, the flexion angles of the hip and knee joints of student subjects during the patient-handling task became larger and that of the trunk became smaller in the group given the educational intervention.

CONCLUSION

The finding of this study suggests that the posture of the study subjects changed to the squat lifting method, which is preferable for reducing the physical load to the lower back, as a result of the educational intervention.

Musculoskeletal complaints among nurses related to patient handling tasks and psychosocial factors--based on logbook registrations

The aims were to evaluate the inter-method reliability of a registration sheet for patient handling tasks, to study the day-to-day variation of musculoskeletal complaints (MSC) and to examine whether patient handling tasks and psychosocial factors were associated with MSC. Nurses (n=148) fulfilled logbooks for three consecutive working days followed by a day off. Low back pain (LBP), neck/shoulder pain (NSP), knee pain (KP), psychosocial factors (time pressure, stress, conscience of the quality of work) and patient transfers and care tasks were reported. The logbook was reliable for both transfer and care tasks. The numbers of nurses reporting MSC and the level of pain increased significantly during the three working days (15%-30% and 17%-37%, respectively) and decreased on the day off. Stress and transfer task were associated with LPB and transfer tasks were associated with KP. Our results confirm a relationship between work factors and MSC and indicate that logs could be one way to obtain a better understanding of the complex interaction of various nursing working conditions in relation to MSC.

Lumbar spine forces during manoeuvring of ceiling-based and floor-based patient transfer devices

Patient handling continues to represent a high risk task for low back pain (LBP) among health caregivers. Previous studies indicated that manual transfers of patients impose unacceptable loads on the spine even when two caregivers perform the transfer. Patient lift devices are considered a potential intervention; however, few biomechanical analyses have investigated the spine loads and LBP risk associated with these transfer devices. This study analysed the 3-D spine forces imposed upon the lumbar spine when 10 subjects manipulated ceiling-based and floor-based patient lifts through various patient handling conditions and manoeuvres. The results indicated that ceiling-mounted patient lift systems imposed spine forces upon the lumbar spine that would be considered safe, whereas floor-based patient handling systems had the potential to increase anterior/posterior shear forces to unacceptable levels during patient handling manoeuvres. Given these findings, ceiling-based lifts are preferable to floor-based patient transfer systems.

Quantifying relationships between selected work-related risk factors and back pain: a systematic review of objective biomechanical measures and cost-related health outcomes

The objective of this investigation was to use published literature to demonstrate that specific changes in workplace biomechanical exposure levels can predict reductions in back injuries. A systematic literature review was conducted to identify epidemiologic studies which could be used to quantify relationships between several well-recognized biomechanical measures of back stress and economically relevant outcome measures. Eighteen publications, describing 15 research studies, which fulfilled search criteria were found. Quantitative associations were observed between back injuries and measures of spinal compression, lifting, lifting ratios, postures, and combinations thereof. Results were intended to provide safety practitioners with information that could be applied to their own work situations to estimate costs and benefits of ergonomic intervention strategies before they are implemented.

Little effect of transfer technique instruction and physical fitness training in reducing low back pain among nurses: a cluster randomised intervention study

The aim of this study was to evaluate the effect of a transfer technique education programme (TT) alone or in combination with physical fitness training (TTPT) compared with a control group, who followed their usual routine. Eleven clinical hospital wards were cluster randomised to either intervention (six wards) or to control (five wards). The intervention cluster was individually randomised to TT (55 nurses) and TTPT (50 nurses), control (76 nurses). The transfer technique programme was a 4-d course of train-the-trainers to teach transfer technique to their colleagues. The physical training consisted of supervised physical fitness training 1 h twice per week for 8 weeks. Implementing transfer technique alone or in combination with physical fitness training among a hospital nursing staff did not, when compared to a control group, show any statistical differences according to self-reported low back pain (LBP), pain level, disability and sick leave at a 12-month follow-up. However, the individual randomised intervention subgroup (transfer technique/physical training) significantly improved the LBP-disability (p = 0.001). Although weakened by a high withdrawal rate, teaching transfer technique to nurses in a hospital setting needs to be thoroughly considered. Other priorities such as physical training may be taken into consideration. The current study supports the findings of other studies that introducing transfer technique alone has no effect in targeting LBP. However, physical training seems to have an influence in minimising the LBP consequences and may be important in the discussion of how to prevent LBP or the recurrence of LBP among nursing personnel.

Low back injury risk during repositioning of patients in bed: the influence of handling technique, patient weight and disability

The objective of the study was to investigate the low back load during repositioning of patients in bed and to assess the influence of patient's weight and disability. Nine female health care workers (HCWs) carried out six patient-handling tasks with different patient weight (59 +/- 1, 83 +/- 2 and 110 +/- 4 kg) and handicap (hemiplegia, paraplegia and near-paralysis). The tasks were performed with optional use of simple, low-tech assistant devices (draw and sliding sheets). Peak low back compression exceeded the National Institute for Occupational Safety and Health action level of 3400 N in 25% of all trials (418). The influence of the HCW, i.e. the technique and assistive devices used, was higher than the effect of weight and disability in all tasks studied. ANOVA showed that on average for the six tasks 37%, 10% and 6% of the variance in low back loading was caused by variation in the factors HCW, patient's weight and disability, respectively. The result of this study is relevant for HCWs. It is shown that the repositioning technique and use of friction-reducing devices have higher influence on the low back load of the HCW than the patient's weight and disability.

Muscular and postural demands of using a massage chair and massage table

OBJECTIVE

The aim of this study was to determine the difference in muscular and postural demands of performing manual therapy using a massage chair and a massage table.

METHODS

Twelve female senior massage therapy students performed two 10-minute regional back massages on a fully clothed client using both a massage chair and massage table. The root mean square was used to determine the mean activation from the electromyographic signal collected from 8 upper extremity muscles. Integrated electromyography was used to compare activation between the 14 massage techniques used. Eight electromagnetic motion capture sensors were attached: the head, trunk, and upper arm, forearm, and hand bilaterally to track segment kinematics and determine total time spent in different postures.

RESULTS

There was higher activation in lumbar erector spinae when using the table and anterior deltoid when using the chair. The anterior deltoid showed a significant condition x period interaction for mean muscle activation for 6 of the 14 massage techniques. The therapists spent significantly more time in mild trunk flexion when using the massage table and significantly more time in severe radial deviation and mild shoulder flexion when using the massage chair.

CONCLUSIONS

The chair and table were more demanding of the anterior deltoid and lumbar erector spinae, respectively. Therapists adopted trunk and wrist postures that would increase the risk of upper extremity injury while using either the massage chair or table.

Justification for a minimal lift program in critical care

This chapter reviews literature pertaining to patient-handling tasks spanning the areas of epidemiology, biomechanics, perceived stresses, education and training programs, and introduction of mechanical patient lifting devices. All findings agree that patient handling is inherently dangerous and has been attributed to the majority of injuries incurred by nursing personnel; however, most studies have been performed in hospitals or long term care settings, but have not been specific to the area of critical care. The critical care environment poses unique challenges for nursing personnel and therefore, to ergonomists.

Nursing staff's perception of changes in patient transfer habits after a course - a phenomenological-hermeneutic study

The objective of the study was to illuminate nursing staff's perception of changes after a course in patient transfer. The learning process took the form of self-experience focusing on the manner of supporting the patient to move independently. A total of 20 participants, who had answered a previously administered questionnaire, were chosen for interviews. The themes concerned the meaning of changing transfer habits. A phenomenological-hermeneutic analysis method showed that changes focused on the patient's body, the staff member's own body or cooperation with the patient. Awareness of one's own body and confidence in one's own ability seem to indicate differences in the manner of supporting the patient to move. The changes in transfer habits varied in content and meaning from person to person, depending on the focus during the transfer. These findings can contribute to an understanding of how change takes place after an educational intervention.

Prevention of low back pain in female eldercare workers: randomized controlled work site trial

STUDY DESIGN

Randomized controlled trial.

OBJECTIVE

To evaluate the effectiveness of an ergonomic and psychosocial intervention in reducing low back pain (LBP) among health care workers.

SUMMARY OF BACKGROUND DATA

LBP and injuries are reported frequently among health care workers worldwide. Improvement of person-transfer techniques is the preferred tool in the prevention of both. Although popular, to our knowledge, any effect has not been documented in controlled trials.

METHODS

Study participants were eldercare workers from 19 eldercare groups randomly assigned to the transfer technique, stress management, or reference arm. A total of 163 individuals (79% of the source population) participated in both baseline and follow-up after 2 years. Outcome was intra-individual change in rating of LBP during the past 3 and 12 months.

RESULTS

We found no difference in LBP in any of the intervention arms over the study period.

CONCLUSION

The study showed no effect of a transfer technique or stress management program targeting LBP. Thus, there is a need for discussing other priorities in the prevention of LBP among health care workers.

Evaluation of nursing students' work technique after proficiency training in patient transfer methods during undergraduate education

The aim of this study was to investigate if nursing students improved their work technique when assisting a simulated patient from bed to wheelchair after proficiency training, and to investigate whether there was a correlation between the nursing students' work technique and the simulated patients' perceptions of the transfer.

METHOD

71 students participated in the study, 35 in the intervention group and 36 in the comparison group. The students assisted a simulated patient to move from a bed to a wheelchair. In the intervention group the students made one transfer before and one after training, and in the comparison group they made two transfers before training. Six variables were evaluated: work technique score; nursing students' ratings of comfort, work technique and exertion, and the simulated patients' perceptions of comfort and safety during the transfer. The result showed that nursing students improved their work technique, and that there was a correlation between the work technique and the simulated patients' subjective ratings of the transfer. In conclusion, nursing students improved their work technique after training in patient transfer methods, and the work technique affected the simulated patients' perceptions of the transfer.

The effect of ergonomic interventions in healthcare facilities on musculoskeletal disorders

BACKGROUND

The high incidence of musculoskeletal disorders (MSDs) among healthcare workers suggests that the introduction of ergonomic interventions could be beneficial. While laboratory studies have clearly documented the efficacy of ergonomic devices, few studies have examined their effectiveness in the healthcare workplace.

METHODS

This study evaluated a statewide program that provided ergonomic consultation and financial support for purchasing ergonomic devices, which aid in patient handling and lifting. Changes in MSD rates between baseline (1 year pre-intervention) and post-intervention (up to 2 years) periods were examined in 100 work units in 86 healthcare facilities.

RESULTS

The median MSD rate decreased from 12.32 to 6.64 per 200,000 employee-hours, a decrease greater than the secular trend for the study period (1999-2003).

CONCLUSIONS

This study suggests that ergonomic consultation and financial support for purchasing ergonomic equipment can be an effective intervention to reduce MSDs among healthcare workers.

An observation instrument for the description and evaluation of patient transfer technique

The aim of the present study was to evaluate the reliability and validity of an observation instrument for patient transfer. The instrument, which consisted of 23 items, was evaluated on five different patient transfer tasks. A weighted score was included to evaluate the performed transfer technique. Four observers were selected for the assessment of instrument intra- and inter-observer reliability. Instrument validity was evaluated by testing whether the instrument could detect a difference between use of a self-chosen and a recommended transfer technique. Furthermore, calculated compression values at L4-L5 were compared with the weighted score for the different transfer technique situations. Eleven items were reliable. Nine items deserve further attention and three items were not reliable. The weighted score was significantly higher for the recommended transfer technique situations (p < 0.01) and an association between the weighted score and the calculated compression values was observed (r = -0.589).