Movement-based feedback may reduce spinal moments in male workers during lift and lowering tasks

A comparison of augmented feedback and didactic training approaches to reduce spine motion during occupational lifting tasks

Manual handling training may be improved if it relied on the provision of individualized, augmented feedback about key movement features. The purpose of this study was to compare the reduction in sagittal spine motion during manual lifting tasks following two training approaches: didactic (DID) and augmented feedback (AUG). Untrained participants (n = 26) completed lifting tests (box, medication bag, and paramedic backboard) and a randomly-assigned intervention involving 50 practice box lifts. Lifting tests were performed immediately before and after training, and one-week after interventions. Both groups exhibited reductions in spine motions immediately and one-week after the interventions. However, the AUG intervention group elicited significantly greater reductions in 5 of 12 between-group comparisons (3 tasks × 4 spine motion variables). The results of the current study support the use of augmented feedback-based approaches to manual handling training over education-based approaches.

Deliberate Practice and Motor Learning Principles to Underpin the Design of Training Interventions for Improving Lifting Movement in the Occupational Sector: A Perspective and a Pilot Study on the Role of Augmented Feedback

Spine posture during repetitive lifting is one of the main risk factors for low-back injuries in the occupational sector. It is thus critical to design appropriate intervention strategies for training workers to improve their posture, reducing load on the spine during lifting. The main approach to train safe lifting to workers has been educational; however, systematic reviews and meta-analyses have shown that this approach does not improve lifting movement nor reduces the risk of low back injury. One of the main limitations of this approach lies in the amount, quality and context of practice of the lifting movement. In this article, first we argue for integrating psychologically-grounded perspectives of practice design in the development of training interventions for safe lifting. Principles from deliberate practice and motor learning are combined and integrated. Given the complexity of lifting, a training intervention should occur in the workplace and invite workers to repeatedly practice/perform the lifting movement with the clear goal of improving their lifting-related body posture. Augmented feedback has a central role in creating the suitable condition for achieving such intervention. Second, we focus on spine bending as risk factor and present a pilot study examining the benefits and boundary conditions of different feedback modalities for reducing bending during lifting. The results showed how feedback modalities meet differently key requirements of deliberate practice conditions, i.e., feedback has to be informative, individualized and actionable. Following the proposed approach, psychology will gain an active role in the development of training interventions, contributing to finding solutions for a reduction of risk factors for workers.

Real-time feedback to reduce low-back load in lifting and lowering

Low-back pain (LBP) is a common health problem. Literature indicates an exposure-response relation between work-related lifting and LBP. Therefore, this study investigated effects of three kinds of real-time feedback on low-back load, quantified as lumbar moments, during lifting. We recruited 97 healthy male and female participants without a recent history of LBP and without prior biomechanical knowledge on lifting. Participants were assigned to groups based on the time of enrollment, filling the four groups in the following order: moment feedback, trunk inclination angle feedback, lumbar flexion feedback, and a control group not receiving feedback. Feedback was given by a sound when a threshold level of the input variable was exceeded. Participants were unaware of the input variable for the feedback, but were instructed to try to avoid the audio feedback by changing their lifting strategy. The groups with feedback were able to reduce the audio feedback and thus changed the input variable towards a more desired level. Lumbar moments significantly decreased over trials in the inclination and moment feedback groups, remained similar in the lumbar flexion group and increased in the control group. Between group comparisons revealed that low-back load was significantly lower in the moment and inclination groups compared to the control group. Additionally, moments were lower in the inclination group than in the lumbar flexion group. Real-time feedback on moments or trunk inclination is a promising tool to reduce low-back load during lifting and lowering.

Using verbal instructions to influence lifting mechanics - Does the directive "lift with your legs, not your back" attenuate spinal flexion?

"Use your legs" is commonly perceived as sound advice to prevent lifting-related low-back pain and injuries, but there is limited evidence that this directive attenuates the concomitant biomechanical risk factors. Body segment kinematic data were collected from 12 men and 12 women who performed a laboratory lifting/lowering task after being provided with different verbal instructions. The main finding was that instructing participants to lift "without rounding your lower back" had a greater effect on the amount of spine flexion they exhibited when lifting/lowering than instructing them to lift "with your legs instead of your back" and "bend your knees and hips". It was concluded that if using verbal instructions to discourage spine flexion when lifting, the instructions should be spine- rather than leg-focused.

Exercise-Based Performance Enhancement and Injury Prevention for Firefighters: Contrasting the Fitness- and Movement-Related Adaptations to Two Training Methodologies

Using exercise to enhance physical fitness may have little impact on performers' movement patterns beyond the gym environment. This study examined the fitness and movement adaptations exhibited by firefighters in response to 2 training methodologies. Fifty-two firefighters were assigned to a movement-guided fitness (MOV), conventional fitness (FIT), or control (CON) group. Before and after 12 weeks of training, participants performed a fitness evaluation and laboratory-based test. Three-dimensional lumbar spine and frontal plane knee kinematics were quantified. Five whole-body tasks not included in the interventions were used to evaluate the transfer of training. FIT and MOV groups exhibited significant improvements in all aspects of fitness; however, only MOV exhibited improvements in spine and frontal plane knee motion control when performing each transfer task (effect sizes [ESs] of 0.2-1.5). FIT exhibited less controlled spine and frontal plane knee motions while squatting, lunging, pushing, and pulling (ES: 0.2-0.7). More MOV participants (43%) exhibited only positive posttraining changes (i.e., improved control), in comparison with FIT (30%) and CON (23%). Fewer negative posttraining changes were also noted (19, 25, and 36% for MOV, FIT, and CON). These findings suggest that placing an emphasis on how participants move while exercising may be an effective training strategy to elicit behavioral changes beyond the gym environment. For occupational athletes such as firefighters, soldiers, and police officers, this implies that exercise programs designed with a movement-oriented approach to periodization could have a direct impact on their safety and effectiveness by engraining desirable movement patterns that transfer to occupational tasks.

Validation of a novel spinal posture monitor: comparison with digital videofluoroscopy

PURPOSE

A novel, minimally invasive posture monitor which can monitor lumbar postures outside the laboratory has demonstrated excellent reliability, as well as concurrent validity compared to a surface marker-based motion analysis system. However, it is unclear if this device reflects underlying vertebral motion.

METHODS

Twelve participants performed full range sagittal plane lumbo-pelvic movements during sitting and standing. Their posture was measured simultaneously using both this device (BodyGuard™) and digital videofluoroscopy.

RESULTS

Strong correlations were observed between the two methods (all r (s) > 0.88). Similarly, the coefficients of determination were high (all r (2) > 0.78). The maximum mean difference between the measures was located in the mid-range of motion and was approximately 3.4° in sitting and 3.9° in standing.

CONCLUSION

The BodyGuard™ appears to be a valid method for analysing vertebral motion in the sagittal plane and is a promising tool for long-term monitoring of spinal postures in laboratory and clinical settings in people with low back pain.

Manual material handling advice and assistive devices for preventing and treating back pain in workers

BACKGROUND

Training and the provision of assistive devices are considered major interventions to prevent back pain and its related disability among workers exposed to manual material handling (MMH).

OBJECTIVES

To determine the effectiveness of MMH advice and training and the provision of assistive devices in preventing and treating back pain.

SEARCH STRATEGY

We searched CENTRAL (The Cochrane Library 2011, issue 1), MEDLINE, EMBASE, CINAHL, Nioshtic, CISdoc, Science Citation Index, and PsychLIT to February 2011.

SELECTION CRITERIA

We included randomised controlled trials (RCT) and cohort studies with a concurrent control group that were aimed at changing human behaviour in MMH and measured back pain, back pain-related disability or sickness absence.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted the data and assessed the risk of bias using the criteria recommended by the Cochrane Back Review Group for RCTs and MINORS for the cohort studies.We based the results and conclusions on the analysis of RCTs only. We compared these with the results from cohort studies.

MAIN RESULTS

We included nine RCTs (20,101 employees) and nine cohort studies (1280 employees) on the prevention of back pain in this updated review. Studies compared training to no intervention (4), professional education (2), a video (3), use of a back belt (3) or exercise (2). Other studies compared training plus lifting aids to no intervention (3) and to training only (1). The intensity of training ranged from a single educational session to very extensive personal biofeedback.Six RCTs had a high risk of bias.None of the included studies showed evidence of a preventive effect of training on back pain.There was moderate quality evidence from seven RCTs (19,317 employees) that those who received training reported levels of back pain similar to those who received no intervention, with an odds ratio of 1.17 (95% confidence intervals (CI) 0.68 to 2.02) or minor advice (video), with a relative risk of 0.93 (95% CI 0.69 to 1.25). Confidence intervals around the effect estimates were still wide due to the adjustment for the design effect of clustered studies.The results of the cohort studies were similar to those of the randomised studies.

AUTHORS' CONCLUSIONS

There is moderate quality evidence that MMH advice and training with or without assistive devices does not prevent back pain or back pain-related disability when compared to no intervention or alternative interventions. There is no evidence available from RCTs for the effectiveness of MMH advice and training or MMH assistive devices for treating back pain. More high quality studies could further reduce the remaining uncertainty.

The Spineangel: Examining the validity and reliability of a novel clinical device for monitoring trunk motion

Spinal loading in excessive and repeated trunk flexion may hinder recovery from acute low back pain. The Spineangel device provides real-time patient biofeedback on trunk flexion and may facilitate recovery from lower back injury. This cross-sectional study evaluates validity and reliability of this device in the laboratory setting. Participants included 18 healthy males. Angular displacements were simultaneously obtained from a Spineangel device placed on the hip and criterion measures of hip, lumbar and total sagittal rotation, and pelvic tilt obtained via 3D Motion Analysis. Each participant repeated four movements five times in a random order (forward bending fingertips-to-knees and to mid-lower leg, full flexion, and full extension). Intraclass correlation coefficients (ICC) for Spineangel measurement of trunk motion were excellent (ICC>0.9). The coefficient of repeatability was less than 5.2 degrees in both flexion and extension. Spineangel showed the highest correlation with Motion Analysis((R)) measurement of pelvic tilt with no statistical difference between measures when bending forward to fingertips-to-knees. Given its high reliability, the Spineangel device has potential as a trunk flexion biofeedback device. Further investigation is required to see if these laboratory results can be reproduced in the clinical setting and to determine the clinical benefits of such a device.