Back muscle response to sudden trunk loading can be modified by training among healthcare workers

Musculoskeletal disorders in aged care workers: a systematic review of contributing factors and interventions

BACKGROUND

There is limited evidence on contributing factors and effective interventions for musculoskeletal injuries in aged care workers.

PURPOSE

To systematically review the factors that contribute to musculoskeletal disorder risk amongst workers in the aged care industry, and to undertake a qualitative comparison of the interventions designed and implemented to prevent injury within this workforce.

METHODS

A systematic review of the literature was conducted in Web of Science, Scopus, ProQuest, Medline, and PubMed. Relevant grey literature was also examined. Articles that reported factors that contribute to musculoskeletal injuries, or interventions to prevent and manage musculoskeletal injuries in residential aged care workers were included.

FINDINGS

Of the 864 articles and 35 grey literature publications found, 63 and 29 were included in the review respectively. Results indicate that physical factors such as manual handling of people, use of assistive devices, and physical work environment are most commonly associated with musculoskeletal disorders in this population. Limited evidence of organisational and psychosocial factors considered staffing issues, work schedules, and violence. The heavy emphasis on physical factors is echoed in the grey literature in relevant guidance material and codes of practice focused on assessment and control of risks. There was limited evidence for interventions specific to aged care; existing evidence focused on equipment, training and education, policy and procedure. Interventions incorporating a combination of approaches, such as equipment and training, showed promise while preliminary evidence of the effectiveness of participatory approaches are positive.

DISCUSSION

Interventions which address multiple types of contributing factors are needed to adequately prevent musculoskeletal injuries in aged care workers. Tweetable abstract: Review of contributing factors, interventions, and application of knowledge for work-related musculoskeletal injuries in aged care.

Maintaining Lumbar Spine Stability: A Study of the Specific and Combined Effects of Abdominal Activation and Lumbosacral Orthosis on Lumbar Intrinsic Stiffness

BACKGROUND

Two potential interventions for enhancing lumbar stability are to actively increase abdominal muscle activity, either through the abdominal drawing-in maneuver (ADIM) or bracing, and passively increase lumbar stiffness using a lumbosacral orthosis (LSO).

OBJECTIVE

To compare the increase in lumbar stiffness after 2 active interventions (ADIM versus bracing) and 1 passive intervention (LSO), and to evaluate the combined effect of active (abdominal bracing) and passive interventions.

METHODS

In this experimental and comparative study, lumbar stiffness, a surrogate measure of lumbar stability, was estimated in 25 healthy individuals during 7 trunk perturbation conditions: (1) control, (2) ADIM, (3) bracing at 5% of right external oblique maximal voluntary activation (5% bracing), (4) bracing at 10% of right external oblique maximal voluntary activation (10% bracing), (5) LSO, (6) LSO plus 5% bracing, and (7) LSO plus 10% bracing. Electromyographic biofeedback of the external oblique was provided on a monitor, while ultrasound was used for the ADIM to ensure a sustained contraction of the transversus abdominis.

RESULTS

The ADIM, 5% bracing, and 10% bracing active interventions generated comparable lumbar stiffness. However, considering that bracing can range from 10% to 20%, it may be superior to hollowing, as further estimated with a mixed-effect statistical model. Combining bracing and an LSO resulted in an additive effect on lumbar stiffness.

CONCLUSION

Bracing and ADIM produced comparable lumbar stiffness, as they were performed at the same overall abdominal activation levels (5% and 10% maximal voluntary activation). The independent effects of bracing and LSO raises the possibility of combining these interventions in some circumstances. J Orthop Sports Phys Ther 2019;49(4):262-271. Epub 18 Jan 2019. doi:10.2519/jospt.2019.8565.

Physical exercise at the workplace prevents deterioration of work ability among healthcare workers: cluster randomized controlled trial

BACKGROUND

Imbalance between individual resources and work demands can lead to musculoskeletal disorders and reduced work ability. The purpose of this study was to investigate the effect of workplace- versus home-based physical exercise on work ability among healthcare workers.

METHODS

Two hundred female healthcare workers (Age: 42.0, BMI: 24.1, work ability index [WAI]: 43.1) from 18 departments at three Danish hospitals participated (Copenhagen, Denmark, Aug 2013-Jan 2014). Participants were randomly allocated at the cluster level to 10 weeks of: 1) workplace physical exercise (WORK) performed during working hours for 5x10 min per week and up to 5 group-based coaching sessions on motivation for regular physical exercise, or 2) home-based physical exercise (HOME) performed during leisure time for 5x10 min per week. Both groups received ergonomic counseling on patient handling and use of lifting aides. The main outcome measure was the change from baseline to 10-week follow-up in WAI.

RESULTS

Significant group by time interaction was observed for WAI (p < 0.05). WAI at follow-up was 1.1 (0.3 to 1.8) higher in WORK compared with HOME corresponding to a small effect size (Cohens'd = 0.24). Within-group changes indicated that between-group differences were mainly caused by a reduction in WAI in HOME. Of the seven items of WAI, item 2 (work ability in relation to the demands of the job) and item 5 (sickness absence during the past year) were improved in WORK compared with HOME (P < 0.05).

CONCLUSIONS

Performing physical exercise together with colleagues at the workplace prevents deterioration of work ability among female healthcare workers.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov NCT01921764 . Registered 10 August 2013.

Effect of Workplace- versus Home-Based Physical Exercise on Muscle Response to Sudden Trunk Perturbation among Healthcare Workers: A Cluster Randomized Controlled Trial

Objectives. The present study investigates the effect of workplace- versus home-based physical exercise on muscle reflex response to sudden trunk perturbation among healthcare workers. Methods. Two hundred female healthcare workers (age: 42 [SD 11], BMI: 24 [SD 4], and pain intensity: 3.1 [SD 2.2] on a scale of 0–10) from 18 departments at three hospitals were randomized at the cluster level to 10 weeks of (1) workplace physical exercise (WORK) performed in groups during working hours for 5 × 10 minutes per week and up to 5 group-based coaching sessions on motivation for regular physical exercise, or (2) home-based physical exercise (HOME) performed during leisure time for 5 × 10 minutes per week. Mechanical and neuromuscular (EMG) response to randomly assigned unloading and loading trunk perturbations and questions of fear avoidance were assessed at baseline and 10-week follow-up. Results. No group by time interaction for the mechanical trunk response and EMG latency time was seen following the ten weeks (P = 0.17–0.75). However, both groups demonstrated within-group changes (P < 0.05) in stopping time during the loading and unloading perturbation and in stopping distance during the loading perturbation. Furthermore, EMG preactivation of the erector spinae and fear avoidance were reduced more following WORK than HOME (95% CI −2.7–−0.7 (P < 0.05) and −0.14 (−0.30 to 0.02) (P = 0.09)), respectively. WORK and HOME performed 2.2 (SD: 1.1) and 1.0 (SD: 1.2) training sessions per week, respectively. Conclusions. Although training adherence was higher following WORK compared to HOME this additional training volume did not lead to significant between-group differences in the responses to sudden trunk perturbations. However, WORK led to reduced fear avoidance and reduced muscle preactivity prior to the perturbation onset, compared with HOME. This trial is registered with Clinicaltrials.gov (NCT01921764).

Effects of kettlebell training on postural coordination and jump performance: a randomized controlled trial

The aim of this study was to investigate the effectiveness of a worksite intervention using kettlebell training to improve postural reactions to perturbation and jump performance. This single-blind randomized controlled trial involved 40 adults (n = 40) from occupations with a high prevalence of musculoskeletal pain and discomfort (mean age 44 years, body mass index 23 kg·m, 85% women). A blinded examiner took measures at baseline and follow-up. Participants were randomly assigned to a training group-doing kettlebell swings 3 times a week for 8 weeks-or to a control group. The outcome measures were postural reactions to sudden perturbation and maximal countermovement jump height. Compared with the control group, the training group had a significant decreased stopping time after perturbation (-109 ms, 95% confidence interval [-196 to -21]). Jump height increased significantly in the training group (1.5 cm, 95% confidence interval [0.5 to 2.5]), but this was nonsignificantly different from control. Kettlebell training improves postural reactions to sudden perturbation. Future studies should investigate whether kettlebell training can reduce the risk of low back injury in occupations with manual material handling or patient handling where sudden perturbations often occur.

Neuromuscular adaptations after a rehabilitation program in patients with chronic low back pain: case series (uncontrolled longitudinal study)

Background

To investigate the impact of a short-term multimodal rehabilitation program for patients with low back pain (LBP) on trunk muscle reflex responses and feedforward activation induced by postural perturbations.

Methods

Case series (uncontrolled longitudinal study). Thirty chronic patients with LBP (21 women and 19 men, mean age 42.6 ± 8.6 years, mean weight 73 ± 14 kg, mean height 174 ± 10 cm) were included. The intervention consisted in a 5-day program including therapeutic education sessions (360 min), supervised abdominal and back muscle strength exercises (240 min), general aerobic training (150 min), stretching (150 min), postural education (150 min) and aqua therapy (150 min). Feedforward activation level and reflex amplitude determined by surface electromyographic activity triggered by postural perturbations were recorded from abdominal and paraspinal muscles in unexpected and expected conditions. Subjects were tested before, just after and again one month after the rehabilitation program.

Results

No main intervention effect was found on feedforward activation levels and reflex amplitudes underlining the absence of changes in the way patients with LBP reacted across perturbation conditions. However, we observed a shift in the behavioral strategy between conditions, in fact feedforward activation (similar in both conditions before the program) decreased in the unexpected condition after the program, whereas reflex amplitudes became similar in both conditions.

Conclusions

The results suggest that a short-term rehabilitation program modifies trunk behavioral strategies during postural perturbations. These results can be useful to clinicians for explaining to patients how to adapt to daily life activities before and after rehabilitation.

Trunk muscle reflex amplitudes increased in patients with subacute, recurrent LBP treated with a 10-week stabilization exercise program

Altered trunk muscle reflexes have been observed in patients with low back pain (LBP). Altered reflexes may contribute to impaired postural control, and possibly recurrence of LBP. Specific stabilization exercise (SSE) programs have been shown to decrease the risk of LBP recurrence in a select group of patients with acute, first episode LBP. It is not known if trunk muscle reflex responses improve with resolution of subacute, recurrent LBP when treated with a SSE program. A perturbation test was used to compare trunk muscle reflexes in patients with subacute, recurrent LBP, before and after 10 weeks of a SSE program and a group of matched control subjects (CNTL). The LBP group pre therapy had delayed trunk muscle reflexes compared with the CNTL group. Post therapy reflex latencies remained delayed, but amplitudes increased. Increased reflex amplitudes could limit excessive movement of the spine when perturbed; potentially helping prevent recurrence.

The influence of kinesiophobia on trunk muscle voluntary responses with pre-programmed reactions during perturbation in patients with chronic low back pain

The purpose of this study was to examine the relation between fear of movement and perturbation induced electromyographic global trunk muscle voluntary responses with pre-programmed reactions among persons with chronic low back pain (CLBP). CLBP subjects (n = 25) were challenged to unexpected and expected perturbations on stable and unstable surfaces. 'Tampa scale for kinesiophobia - Adjusted version-13' was used to measure kinesiophobia. Regression analysis revealed significant negative correlation between kinesiophobia scores and voluntary responses of rectus abdominis (RA) for unexpected perturbations on stable (r = -0.69, 95% of CI: -0.85 to -0.40, p < 0.000, r(2) = 0.41) and unstable surfaces (r = -0.47, 95% of CI: -0.72 to -0.09, p < 0.018, r(2) = 0.29). The activity of erector spinae was not influenced by most of testing conditions in the study except task on unstable surface for expected perturbation (r = -0.593, 95% of CI: -0.8 to -0.25, p = 0.002, r(2) = 0.15). RA activity and kinesiophobia score of the CLBP population was significantly inversely associated during anteriorly directed unexpected perturbations. In our study, the significant association between fear of movement and the trunk muscle responses was differentially influenced by expected and unexpected postural demands.

What constitutes effective manual handling training? A systematic review

BACKGROUND

Injuries caused by manual handling are a major burden to society. Manual handling training programmes have been designed to reduce the likelihood of injury among the workforce; however, concerns have been raised over the efficacy of current manual handling training methods.

AIMS

To undertake a systematic review of the literature examining the effectiveness of different approaches to training in manual handling.

METHODS

Peer-reviewed publications along with published conference proceedings published in English, between 1980 and 2009, on the topic of manual handling training comprised the search criteria. A published checklist for reviewing papers was selected, which formed the basis for assessing the quality of the papers reviewed.

RESULTS

A total of 1827 papers were located. Following elimination of duplicates, 221 papers were collected and reviewed. Of these, 53 papers were intervention studies with the primary aim of investigating the effectiveness of manual handling training. The review identified little evidence supporting the effectiveness of both technique- and educational-based manual handling training. In addition, there was considerable evidence supporting the idea that the principles learnt during training are not applied in the working environment. Strength and flexibility training shows promise; however, further research is needed to ascertain whether such an intervention is sustainable over the long term.

CONCLUSIONS

The evidence collected indicates that manual handling training is largely ineffective in reducing back pain and back injury. High priority should be given to developing and evaluating multidimensional interventions, incorporating exercise training to promote strength and flexibility, which are tailored to the industrial sector.