Development and Feasibility Testing of a Contextual Patient Movement Intervention.

INTRODUCTION: Nurses and emergency medical services workers frequently suffer musculoskeletal injuries at a disproportionate rate in relation to the rest of the population. The most common form of this musculoskeletal injury is lumbar spine injury. The purpose of this study was to develop and conduct phase 1 feasibility testing of a contextual lifting intervention that reduces the risks of low back injury. METHODS: This study was an intervention development and phase 1 feasibility test. The intervention was created on the basis of weightlifting techniques to specifically reduce the incidence injury related to valgus knee, asymmetrical lifting technique, and rotation of the trunk and pelvis. Motion capture technology (Xsens; Xsens Technologies) was used while 17 nursing students completed the direct patient lift from the floor, the lift from the floor with a manikin attached to a rigid spine board, the push portion of the horizontal transfer, and the pull portion of the horizontal transfer. Pre- and postintervention data were collected. Linear mixed model regression, with pairwise comparisons, was conducted for each lift at the time points of preintervention, immediately after the intervention, and 1-month postintervention. RESULTS: Significant changes were noted between the initial lifting techniques used and those used after the intervention. The maximum lever arm distance, defined as the distance from L5-S1 to the center of the force applied to the load, showed a significant reduction after the intervention in 3 of the 4 movements. DISCUSSION: Our results support the idea that injury risk can be reduced through appropriate contextual training methods.

Use of the lower extremity functional test to predict injury risk in active athletes.

BACKGROUND: The purpose of the current study was to assess the reliability and validity of the lower extremity functional test (LEFT) for predicting low back and lower limb injury in active athletes. METHODS: Seventy athletes (45M, 25F; mean age: 21±2 years) from seven different sports volunteered. The LEFT was a battery of five weight-bearing functional movements involving different movement planes, directions, modes, and at varying intensities. Both legs were assessed in a random order and each athlete was given both movement quality and associated symptom scores. Intratester, intrarater and inter-rater reliability were evaluated. Participants were followed up for 12 months, and their exposure to sport and subsequent injuries were recorded. Independent samples t-tests were performed to determine if a significant difference existed in LEFT scores between injured and non-injured athletes. Receiver operating characteristic (ROC) curve analysis was employed to assess the instrument's capacity to predict injury. RESULTS: The intratester reliability ICC2, 1 was 0.875. The ICC2, 3 of intrarater reliability was 0.953 and the inter-rater reliability was 0.949, respectively. Nineteen participants had an injury in the low back or lower limb within the following 12 months. Injured athletes had significant lower movement quality and symptom scores of the LEFT than non-injured (t=4.278, P=0.000, Cohen's d=1.2; t=3.654, P=0.001, Cohen's d=1.3, respectively). When movement quality or symptom score alone was included in the ROC analysis, the area under the ROC curve (AUC) scores were 0.772 (P=0.000, 95% CI: 0.653-0.891) and 0.771 (P=0.001, 95% CI: 0.638-0.905), respectively. When movement quality and symptom scores were combined to predict injury, the AUC discrimination score was 0.853 (P=0.000, 95% CI: 0.754-0.953), resulting in 85.3% of cases being correctly predicted as low back or lower limb injured/noninjured. CONCLUSIONS: The findings from the current study suggest that the LEFT appears to be a reliable and valid functional assessment tool for predicting low back or lower limb injury risk in these college athletes, especially when movement quality and symptom scores were used in combination.

Injuries and illnesses among competitive Norwegian rhythmic gymnasts during preseason: a prospective cohort study of prevalence, incidence and risk factors.

OBJECTIVES: Rhythmic gymnastics is an Olympic sport that demands high training volume from early age. We investigated the extent of, and risk factors for, injuries among competitive Norwegian rhythmic gymnasts. METHODS: One hundred and seven of 133 (80.5%) female rhythmic gymnasts (mean age: 14.5 years (SD 1.6), mean body mass index: 18.9 (SD 2.2)) participated. All gymnasts completed a baseline questionnaire and the 'Triad-Specific Self-Report Questionnaire'. Injuries, illnesses and training hours were recorded prospectively for 15 weeks during preseason using the 'Oslo Sports Trauma Research Center Questionnaire on Health Problems' (OSTRC-H2). RESULTS: Response rate to OSTRC-H2 was 97%. Mean overuse and acute injury prevalence were 37% (95% CI: 36% to 39%) and 5% (95% CI: 4% to 6%), respectively. Incidence was 4.2 overuse injuries (95% CI: 3.6 to 4.9) and 1.0 acute injuries (95% CI: 0.5 to 1.6) per gymnast per year. Overuse injuries in knees, lower back and hip/groin represented the greatest burdens. Previous injury increased the odds of injury (OR 30.38, (95% CI: 5.04 to 183.25)), while increased age (OR 0.61 per year, (95% CI: 0.39 to 0.97)) and presence of menarche (OR: 0.20, (95% CI: 0.06 to 0.71)) reduced the odds of all injuries and substantial injuries, respectively. CONCLUSIONS: Overuse injuries were common among Norwegian rhythmic gymnasts. Younger gymnasts had higher all-injury risk. Gymnasts who were not menstruating had higher substantial injury risk. Injury prevention interventions should start at an early age and focus on preventing knee, lower back and hip/groin injuries.

Modifying bowling kinematics in cricket pace bowlers with exercise-based injury prevention: A cluster-randomised controlled trial.

OBJECTIVES: Undesirable bowling kinematics can increase the risk of low back injury. This study investigated if an exercise-based injury prevention program (IPP) could modify bowling kinematics in community-level adolescent pace bowlers. DESIGN: Cluster-randomised controlled trial. METHODS: Pace bowlers from eight cricket organisations were cluster-randomised into an intervention or control group. At baseline and follow-up sessions biomechanical bowling data were collected. Between sessions, the intervention group completed an eight-week IPP while the control continued their normal cricket activity. Treatment effects (95% CI) were estimated with linear mixed models. RESULTS: There were significant treatment effects favouring the intervention group for shoulder counter-rotation (-3.8°; -7.2° to -0.3°) and lateral trunk flexion relative to the pelvis (-2.2°; -4.0° to -0.5°). Shoulder counter-rotation also increased in the control group by 2.2° (Cohen's d=0.22). There were no effects of the intervention on: lateral trunk flexion at front foot contact (FFC) (1.2°; -2.5° to 4.8°), lateral trunk flexion at ball release (BR) (-0.5°; -3.0° to 2.0°), pelvis rotation at FFC (0.9°; -4.0° to 2.2°), pelvis rotation at BR (-1.1°; -5.7° to 3.6°), front hip angle at FFC (1.6°; -3.6° to 6.7°), front hip angle at BR (-1.6°; -5.0° to 1.9°), front knee angle at FFC (-1.1°; -4.5° to 2.3°), front knee angle at BR (1.7°; -5.6° to 9.1°), or ball velocity (1.1kmh-1; -7.5kmh-1 to 9.7kmh-1). CONCLUSIONS: The IPP maintained shoulder counter-rotation and lateral trunk flexion relative to the pelvis in the intervention group and this could attenuate injury risk. No treatment effects were observed for lower-limb kinematics.

Reducing lumbar spine flexion using real-time biofeedback during patient handling tasks.

BACKGROUND: Patient handling activities require caregivers to adopt postures that increase the risk of back injury. Training programs relying primarily on didactic methods have been shown to be ineffective at reducing this risk. The use of real-time biofeedback has potential as an alternative training method. OBJECTIVE: To investigate the effect of real-time biofeedback on time spent by caregivers in end-range lumbar spine flexion. METHODS: Novice participants were divided into intervention (n = 10) and control (n = 10) groups and were asked to perform a set of simulated care activities eight times on two consecutive days. Individuals in the intervention group watched a training video on safer movement strategies and received real-time auditory feedback from a wearable device (PostureCoach) in four training trials whenever their lumbar spine flexion exceeded a threshold (70% of maximum flexion). Changes in end-range lumbar spine flexion were compared between groups and across trials. RESULTS: Participants in the intervention group saw reductions in end-range lumbar spine flexion during the simulated patient handling tasks at the end of the training compared to their baseline trials while there was no change for the control group. CONCLUSIONS: The training program including PostureCoach has the potential to help caregivers learn to use safer postures that reduce the risk of back injury.

Effects of Nordic Hamstring Exercise on Hamstring Injuries in High School Soccer Players: A Randomized Controlled Trial.

We evaluated a range of physical characteristics related to hamstring injuries, as well as the Nordic Hamstring Exercise compliance rate, and whether this influenced the rate hamstring injury. Subjects comprised 259 male soccer players from seven high schools randomly clustered into two groups, a Nordic Hamstring Exercise group and a control group. Training and match time were logged, as well as details of hamstring injury, and subsequent time lost to hamstring injury recorded over a period of 27 weeks. The Nordic Hamstring Exercise compliance rate, injury rate per 10000 playing hours and time-lost-to-sport-injury rate were calculated. The relative risk and hamstring injury severity were also calculated. The hamstring injury rate was 1.04/10 000 h in the control group and 0.88/10 000 h in the intervention group. The relative risk for hamstring injury was 1.14. The time-lost to injury rate was 1116.3/10 000 h in the control group and 113.7/10 000 h in the intervention group; with relative risk 9.81. The Nordic Hamstring Exercise in high school soccer players significantly reduced hamstring injury severity compared to a control intervention. Our results indicate that the time-lost to injury rate should be taken into account when analyzing the severity of hamstring injury.

Mining-Related Lower Back Injuries and the Compensation Process: An Injured Worker's Journey.

Background: In Ontario, when an occupational injury occurs in the mining industry, there is often a need to interact with the Workplace Safety and Insurance Board (WSIB). During this process, miners experience economic, social, and mental health-related issues that can affect their overall well-being. This study aimed to determine the impact of a lower back injury and the WSIB claim process experience expressed by some male, underground miners in Sudbury, Ontario, Canada. Methods: A qualitative descriptive study design that utilized in-depth, individual qualitative interviews was conducted. Twelve male participants (underground miners) were interviewed in Sudbury, Ontario. Interviews were transcribed and thematically analyzed. Findings: The results emphasized the need for improved communication, the necessity for resources to be allocated to enhance public discussion about injury prevention, the social and economic burden that miners and their families face, and the power imbalances between injured miners and the companies that were meant to support them. Conclusion/Application to Practice: The findings indicate that several areas require improvement for an injured miner who submits a WSIB claim. Ideally, participants wanted an improved and streamlined process for reporting an injury and for WSIB claim management. These findings suggest that occupational health practices that foster a safe and healthy work environment in the mining industry must be promoted, which will help to guide future policies that enhance support for an injured worker and the WSIB claim process.

Spine loading during laboratory-simulated fireground operations - inter-individual variation and method of load quantification.

Spine loading data are needed to design low-back health-preserving ergonomic interventions for firefighters. Study objectives were to quantify spine loads during simulated fireground operations using simple (polynomial) and advanced (EMG-assisted musculoskeletal model) methods and to describe the variation in spine loads between performers (N = 20). Spine compression forces differed by as much as 5.5 times bodyweight between individuals performing identical tasks. Anteroposterior and mediolateral shear forces varied by as much 3.2 and 2.1 times bodyweight between individuals performing the same tasks, respectively. Large variations in spine load magnitudes were documented regardless of whether simple or advanced quantification methods were used. Results suggest that low-back loading demands on the fireground would vary widely depending on the physical characteristics of individual firefighters, movement strategies employed, and tasks performed. Thus, personalised ergonomic interventions are warranted to regulate spine loading and load tolerance in firefighters. Practitioner summary: Even when performing the same work, the associated spine loading demands will vary widely across people due to differences in their body sizes, shapes, and movement strategies. Therefore, personalised interventions are needed to regulate spine loading and load tolerance in workers (e.g. obesity prevention, physical capacity-building exercise, and movement [re]training).

How do manual handling advisors and physiotherapists construct their back beliefs, and do safe lifting posture beliefs influence them?

BACKGROUND: The Back-Pain Attitudes (Back-PAQ) questionnaire measures back beliefs across 6 domains. Our previous study showed that manual handling advisors (MHAs) have more negative beliefs than physiotherapists (PTs), and those who think straight back lifting is safer than a rounder back have more negative beliefs. However, exactly which domains of the Back-PAQ are most negative is unknown. OBJECTIVES: Gain deeper understanding of how MHAs and PTs construct their back beliefs, and relate this safe lifting posture beliefs. DESIGN: Data was collected via an electronic survey. METHOD: Participants' back beliefs were collected via the Back-PAQ. They were also asked to select the safest lifting posture from four options: two with a straight back; two with a rounder back. Back beliefs were analysed in the 6 domains that construct the Back-PAQ. Relationships were investigated using multiple linear and regression models. RESULTS: 400 PTs and MHAs completed the survey. MHAs scored higher (more negative beliefs) than PTs across all 6 domains, and those who perceive straight back lifting as safest scored higher across five of the 6 domains. The belief to keep active with back pain was common among all groups, but MHAs and those who prefer straight back lifting believe the back is vulnerable and more in need of protection. CONCLUSION: While all believe staying active is beneficial for back pain, residual negative beliefs regarding the vulnerability of the spine persist. Education campaigns may need to emphasise a 'trust your back' message rather than a 'protect your back' message while encouraging activity.

Shoulder and Lower Back Joint Reaction Forces in Seated Double Poling.

Overuse injuries in the shoulders and lower back are hypothesized to be common in cross-country sit-skiing. Athletes with reduced trunk muscle control mainly sit with the knees higher than the hips (KH). To reduce spinal flexion, a position with the knees below the hips (KL) was enabled for these athletes using a frontal trunk support. The aim of the study was to compare the shoulder joint (glenohumeral joint) and L4-L5 joint reactions of the KL and KH sitting positions. Five able-bodied female athletes performed submaximal and maximal exercise tests in the sitting positions KL and KH on a ski ergometer. Measured pole forces and 3-dimensional kinematics served as input for inverse-dynamics simulations to compute the muscle forces and joint reactions in the shoulder and L4-L5 joint. This was the first musculoskeletal simulation study of seated double poling. The results showed that the KH position was favorable for higher performance and decreased values of the shoulder joint reactions for female able-bodied athletes with full trunk control. The KL position was favorable for lower L4-L5 joint reactions and might therefore reduce the risk of lower back injuries. These results indicate that it is hard to optimize both performance and safety in the same sit-ski.

Assessment of low back disorders risk based on allowable weight limits for manual lifting in Iran.

In 2011, load limits for manual lifting were adopted in Iran to protect workers from low back injury without prior testing of accuracy with Iranian workers. This investigation examined how accurate the adopted ACGIH TLVs at the allowable limits predict risk for LBP disorders for a group of Iranian workers using biomechanical criteria. Testing took place in the laboratory with participants completing a series of 2-handed lifting tasks as defined in the Iranian Guideline for Manual Lifting. To test accuracy, both compression and shear forces were estimated for fifteen male Iranian workers who completed 25 lift combinations that varied in height and reach with the maximal allowable load. The findings, when compared to a risk threshold of 3400 N compression and 700 N shear, showed above-threshold forces for compression and little-to-no safety margins with repetitive lifting for most lifts at torso height and below. Since Government, employers and workers use these guidelines to decide on work/workplace design; these guidelines require further review and revision based on the anthropometrics of Iranian people.

Time course of the acute effects of core stabilisation exercise on seated postural control.

Core stabilisation exercises are often promoted for purposes ranging from general fitness to high-performance athletics, and the prevention and rehabilitation of back troubles. These exercises, when performed properly, may have the potential to enhance torso postural awareness and control, yet the potential for achieving immediate gains has not been completely studied. Fourteen healthy young participants performed a single bout of non-fatiguing core stabilisation exercise that consisted of repeated sets of 2 isometric exercises, the side bridge and the four-point contralateral arm-and-leg extension. Seated postural control, using an unstable balance platform on top of a force plate, was assessed before and after exercise, including multiple time points within a 20-minute follow-up period. Nine standard postural control variables were calculated at each time point, including sway displacement and velocity ranges, root mean squares and cumulative path length. Statistical analysis showed that none of the postural control variables were significantly different at any time point following completion of core stabilisation exercise. Thus, we conclude that a single bout of acute core stabilisation exercise is insufficient to immediately improve seated trunk postural control in young healthy individuals.

What do physiotherapists and manual handling advisors consider the safest lifting posture, and do back beliefs influence their choice?

BACKGROUND: It is commonly believed lifting is dangerous and the back should be straight during lifting. These beliefs may arise from healthcare professionals, yet no study has evaluated the lifting and back beliefs of manual handling advisors (MHAs) and physiotherapists (PTs). OBJECTIVES: To evaluate (i) what lifting technique MHAs and PTs perceive as safest, and why, and (ii) the back pain beliefs of MHAs and PTs. DESIGN: Data was collected via an electronic survey. METHOD: Participants selected the safest lifting posture from four options: two with a straight back and two with a more rounded back, with justification. Back beliefs were collected via the Back-Pain Attitudes Questionnaire (Back-PAQ). Relationships were investigated using multiple linear and logistic regression models. RESULTS: 400 PTs and MHAs completed the survey. 75% of PTs and 91% of MHAs chose a straight lifting posture as safest, mostly on the basis that it avoided rounding of the back. MHAs scored significantly higher than PTs on the Back-PAQ instrument (mean difference = 33.9), indicating more negative back beliefs. Those who chose the straight back position had significantly more negative back beliefs (mean 81.9, SD 22.7) than those who chose a round back lift (mean 61.7, SD 21.1). CONCLUSION: Avoiding rounding the back while lifting is a common belief in PTs and MHAs, despite the lack of evidence that any specific spinal posture is a risk factor for low back pain. MHAs, and those who perceived a straight back position as safest, had significantly more negative back beliefs.

The influence of fatigue and chronic low back pain on muscle recruitment patterns following an unexpected external perturbation.

BACKGROUND: Chronic low back pain (CLBP) has been associated with altered trunk muscle responses as well as increased muscle fatigability. CLBP patients and fatigued healthy subjects could experience similar neuromuscular strategies to attempt to protect the spine. The current study examined muscle activation differences between healthy and CLBP subjects following a perturbation. In addition, the possible role of muscle fatigue was evaluated by investigating the healthy control subjects in a non-fatigued and a fatigued condition. Both experiments were combined to evaluate possible similar strategies between CLBP and fatigued samples. METHODS: Cross-sectional study where 24 CLBP subjects and 26 healthy subjects were evaluated. Both groups (CLBP vs. healthy) and both conditions (non-fatigued and a fatigued condition) were evaluated while a weight was suddenly dropped on a held tray. Erector spinae, multifidus, obliques and biceps brachii were recorded using surface electromyography. Variables describing the bursts timing and variables describing the amount of muscle activity (number of bursts and amplitude increase) post impact were studied. The analysis between groups and conditions was carried out using ANOVAs with repeated measurements for the muscle factor. RESULTS: CLBP subjects reacted similarly to healthy subjects regarding muscle activity post impact. However, the CLBP group showed temporal characteristics of muscle activity that were in between the fatigued and non-fatigued healthy group. Clear differences in muscle activity were displayed for healthy subjects. Fatigued healthy subjects presented more reduced activity after impact (upper limb and trunk muscles) than non-fatigued healthy subjects and different temporal characteristic in the same way than CLBP patients. This same temporal characteristic with CLBP and healthy fatigued people was a delay of the first burst of muscle activity after impact. CONCLUSION: Though similar muscle pattern existed between CLBP and healthy people, CLBP temporal characteristics of muscle activity showed a pattern in between healthy people and fatigued healthy people. While the temporal muscle pattern dysfunction used by CLBP subjects could be related to maladaptive patterns, temporal and muscle activity characteristics used by healthy fatigued people may lead to back injuries.

Artificial neural networks to predict 3D spinal posture in reaching and lifting activities; Applications in biomechanical models.

Spinal posture is a crucial input in biomechanical models and an essential factor in ergonomics investigations to evaluate risk of low back injury. In vivo measurement of spinal posture through the common motion capture techniques is limited to equipped laboratories and thus impractical for workplace applications. Posture prediction models are therefore considered indispensable tools. This study aims to investigate the capability of artificial neural networks (ANNs) in predicting the three-dimensional posture of the spine (S1, T12 and T1 orientations) in various activities. Two ANNs were trained and tested using measurements from spinal postures of 40 male subjects by an inertial tracking device in various static reaching and lifting (of 5kg) activities. Inputs of each ANN were position of the hand load and body height, while outputs were rotations of the three foregoing segments relative to their initial orientation in the neutral upright posture. Effect of posture prediction errors on the estimated spinal loads in symmetric reaching activities was also investigated using a biomechanical model. Results indicated that both trained ANNs could generate outputs (three-dimensional orientations of the segments) from novel sets of inputs that were not included in the training processes (root-mean-squared-error (RMSE)<11° and coefficient-of-determination (R2)>0.95). A graphic user interface was designed and made available to facilitate use of the ANNs. The difference between the mean of each measured angle in a reaching task and the corresponding angle in a lifting task remained smaller than 8°. Spinal loads estimated by the biomechanical model based on the predicted postures were on average different by < 12% from those estimated based on the exact measured postures (RMSE=173 and 35N for the L5-S1 compression and shear loads, respectively).

Moving and handling: reducing risk through assessment.

Manual handling injuries can occur almost anywhere in a healthcare environment, and most staff perform a variety of moving and handling tasks every day. Heavy lifting, awkward posture, and previous or existing injury can increase the risk of musculoskeletal disorders. A healthcare professional's involvement in moving and handling is more widespread than it might appear, and their actions and understanding of techniques, legislation and guidelines have a direct effect on patient care. Every situation that involves the handling, or partial handling, of a person presents varying levels of risk to the patient and the carer. Maintaining a good level of patient mobility and independence is an essential part of care delivery and can reduce the risk of long-term physical and psychological effects. Delivery of care should focus on the individual's capacity, not their incapacity, to ensure that they are treated with dignity and respect.

Thermo-physiological comfort of soft-shell back protectors under controlled environmental conditions.

The aim of the study was to investigate thermo-physiological comfort of three back protectors identifying design features affecting heat loss and moisture management. Five volunteers tested the back protectors in a climatic chamber during an intermittent physical activity. Heart rate, average skin temperature, sweat production, microclimate temperature and humidity have been monitored during the test. The sources of heat losses have been identified using infrared thermography and the participants answered a questionnaire to express their subjective sensations associated with their thermo-physiological condition. The results have shown that locally torso skin temperature and microclimate depended on the type of back protector, whose design allowed different extent of perspiration and thermal insulation. Coupling physiological measurements with the questionnaire, it was found that overall comfort was dependent more on skin wetness than skin temperature: the participants preferred the back protector with the highest level of ventilation through the shell and the lowest level of microclimate humidity.