The impact of office chair features on lumbar lordosis, intervertebral joint and sacral tilt angles: a radiographic assessment.

BACKGROUND: The purpose of this study was to determine which office chair feature is better at improving spine posture in sitting. METHOD: Participants (n = 28) were radiographed in standing, maximum flexion and seated in four chair conditions: control, lumbar support, seat pan tilt and backrest with scapular relief. Measures of lumbar lordosis, intervertebral joint angles and sacral tilt were compared between conditions and sex. RESULTS: Sitting consisted of approximately 70% of maximum range of spine flexion. No differences in lumbar flexion were found between the chair features or control. Significantly more anterior pelvic rotation was found with the lumbar support (p = 0.0028) and seat pan tilt (p < 0.0001). Males had significantly more anterior pelvic rotation and extended intervertebral joint angles through L1-L3 in all conditions (p < 0.0001). CONCLUSION: No one feature was statistically superior with respect to minimising spine flexion, however, seat pan tilt resulted in significantly improved pelvic posture. Practitioner Summary: Seat pan tilt, and to some extent lumbar supports, appear to improve seated postures. However, sitting, regardless of chair features used, still involves near end range flexion of the spine. This will increase stresses to the spine and could be a potential injury generator during prolonged seated exposures.

The biomechanical demands of manual scaling on the shoulders & neck of dental hygienists.

The purpose of this study was to evaluate the postural and muscular demands placed on the shoulders and neck of dental hygienists when performing a simulated manual scaling task. Nineteen healthy female dental hygienists performed 30-min of simulated manual scaling on a manikin head in a laboratory setting. Surface electromyography was used to monitor muscle activity from several neck and shoulder muscles, and neck and arm elevation kinematics were evaluated using motion capture. The simulated scaling task resulted in a large range of neck and arm elevation angles and excessive low-level muscular demands in the neck extensor and scapular stabilising muscles. The physical demands varied depending on the working position of the hygienists relative to the manikin head. These findings are valuable in guiding future ergonomics interventions aimed at reducing the physical exposures of dental hygiene work. Practitioner Summary: Given that this study evaluates the physical demands of manual scaling, a procedure that is fundamental to dental hygiene work, the findings are valuable to identify ergonomics interventions to reduce the prevalence of work-related injuries, disability and the potential for early retirement among this occupational group.

The Effect of Phase of Menstrual Cycle on Joint Mobility in the Cervical Spine and Extremities in Nulliparous Women: A Cross-Sectional Study.

OBJECTIVE: The purpose of this study was to investigate the range of motion (ROM) of various joints in women throughout the menstrual cycle to determine whether there would be a difference in the ROM between the luteal and follicular phases during extension at the fifth metacarpophalangeal joint and bilateral rotation of the cervical spine in young adult nulliparous women. METHODS: Sixteen nulliparous women of childbearing age (mean age, 26 years) were recruited from the academic institution where the study was being performed. Participants were randomized into and tested during either the luteal or follicular phases of the menstrual cycle. In the following month, participants were tested in the opposite phases of the menstrual cycle. All testing was performed by a doctor of chiropractic. Differences in ROM were measured in single joint movements (fifth digit hyperextension) and in multijoint movements (bilateral cervical rotation) using an electromagnetic sensor system. RESULTS: No significant effects of phase were found on peak ROM of the fifth digit or during cervical spine rotation (left, right, or bilaterally), irrespective of trial. CONCLUSION: There is no difference in ROM of the cervical spine or the fifth metacarpophalangeal joint, regardless of the phase of menses, suggesting there is likely no hormonal influence on these structures during the follicular or luteal phases.

Working position influences the biomechanical demands on the lower back during dental hygiene.

This investigation monitored the biomechanical demands on the lower back during simulated dental hygiene work. A total of 19 female, registered dental hygienists performed 30 continuous minutes of manual scaling (plaque removal) of a manikin's teeth while seated. We monitored the working location and orientation of the dental hygienists, with respect to the manikin, along with their spine kinematics, spine extensor muscle activities and seat pressure, throughout the 30 min. A clock representation was used to express the working location. The location significantly influenced the dental hygienists' pelvic orientation with respect to the manikin, spine posture, erector muscle activity and pressure distribution. Findings from this study suggest that the prevalence of lower back pain amongst dental hygienists may be directly related to low-level tonic activity of the spine's extensor musculature, and the combined flexed and axially rotated spine postures. Practitioner Summary: Low back pain (LBP) is prevalent in dental hygienists, yet occupational demand on the low back has not been investigated. Posture, muscle activity and seat pressure were monitored. Combined spine rotation and flexion, and tonic activity of the extensor musculature may be related to LBP in dental hygienists.

The development and evaluation of an online educational tool for the evidence-based management of neck pain by chiropractic teaching faculty.

OBJECTIVE: To develop an online, interactive educational tool to deliver an evidence-based clinical practice guideline to faculty members at a Canadian chiropractic college. Second, to evaluate the learning, design, and engagement constructs of the tool in a sample of chiropractic faculty members. METHODS: Using an integrated knowledge translation methodology and the Knowledge to Action Framework, we developed an evidence-based online learning tool. The context of the tool focused on a clinical practice guideline on the management of neck pain. We evaluated the learning, design, and engagement constructs in a sample of faculty members and residents using the Learning Object Evaluation Scale for Students. Participants were also asked to provide suggestions for improvement of the tool. RESULTS: Sixteen participants completed the evaluation. Most (68.8%) participants were chiropractors, 75% were male and 56% were between the ages of 25 and 44 years. At least 75% of participants agreed that the learning, design, and engagement constructs of the learning tool were adequate. The open-ended suggestions unveiled 3 pedagogical themes, relating to multimedia, thinking skills, and learner control, within the tool that could benefit from further development. These themes informed recommendations to improve the tool. CONCLUSION: Our online, interactive, module-based learning tool has sound pedagogical properties. Further research is needed to determine if its use is associated with a change in knowledge.

Using technology-based educational interventions to improve knowledge about clinical practice guidelines.

OBJECTIVE: To describe the best evidence on the effectiveness of technology-based learning tools designed to improve knowledge of health care providers about clinical practice guidelines (CPGs). METHODS: We conducted a systematic review, searching MEDLINE, Embase, and CINAHL from inception to July 2018. Included studies investigated the effectiveness of any technology-based learning tools developed to improve knowledge of health care providers about CPGs. We used a 2-phase screening process to determine eligibility. Pairs of reviewers critically appraised relevant studies using the Scottish Intercollegiate Guidelines Network checklist for randomized controlled trials or the National Institutes of Health checklist for pre- and postintervention trials. Evidence from internally valid studies was described using a best-evidence summary. We conducted a sensitivity analysis to determine whether results varied according to methodological quality. RESULTS: Twenty-five of 8321 articles met our selection criteria. Six studies had a low risk of bias and were included in this review. Spaced education was associated with improvement in knowledge; however, its effectiveness relative to other interventions is unknown. Module-based online educational interventions were associated with improvement in knowledge of CPGs; however, they may not be more effective than paper-based self-learning or in-person workshops. The sensitivity analysis determined that the evidence was similar between the high and low risk of bias studies. CONCLUSION: Module-based- and spaced-education interventions may be beneficial for improving health care providers' knowledge of CPGs; however, much of the evidence toward their use is preliminary.

Naturopathy Special Interest Group Research Capacity and Needs Assessment Survey.

OBJECTIVES: Despite recent shifts in regulation and recognition of the role that naturopathy plays in health care delivery in Canada, comparatively little research has been conducted regarding individuals who conduct naturopathy-related research. A survey was undertaken to better understand the needs and capacity of these individuals to conduct more research. DESIGN, SETTING, AND SUBJECTS: The Naturopathy Special Interest Group (N-SIG) of the Interdisciplinary Network of Complementary and Alternative Medicine (INCAM) Researchers created and distributed a survey of individuals interested in naturopathy-related research to assess gaps between current and desired research activity and needs for further participation. OUTCOME MEASURES: Results from a previous pilot study (2014; n = 58) were used to inform the design and distribution. This study received approval and oversight from the Research Ethics Board of the Canadian College of Naturopathic Medicine. RESULTS: The survey was completed by 201 individuals (∼5%-10% of all naturopathic doctors and naturopathy researchers in Canada). The majority (70%) had no peer-reviewed publication experience; however, 63% reported having published in a nonpeer-reviewed medium. Respondents reported differing levels of confidence in completing various components of a research project. Frequently selected obstacles included lack of time due to professional and personal obligations, as well as insufficient training, funding, and mentorship. The greatest identified needs for participation in research were mentorship/support, access to a wider degree of scientific journals, and targeted funding opportunities for CAM research. Overall, the results of this survey suggest that there is interest in further conducting naturopathy-related research in Canada. There are individuals who are already involved and have expressed skills in the area of evidence-based medicine. Mentorship, research training, resources, and critical appraisal and writing skills may be important leverage points. CONCLUSION: Findings from this investigation will be used to inform an agenda for naturopathy-related research and activities of the N-SIG with respect to enhancing research capacity. Other CAM groups or geographic regions could consider using similar methodology to assess capacity and needs for research participation.

Selecting and training opinion leaders and best practice collaborators: experience from the Canadian Chiropractic Guideline Initiative.

OBJECTIVES: To describe the process for selecting and training chiropractic opinion leaders (OLs) and best practice collaborators (BPCs) to increase the uptake of best practice. METHODS: In Phase 1, OLs were identified using a cross-sectional survey among Canadian chiropractic stakeholders. A 10-member committee ranked nominees. Top-ranked nominees were invited to a training workshop. In Phase 2, a national e-survey was administered to 7200 Canadian chiropractors to identify additional OLs and BPCs. Recommended names were screened by OLs and final selection made by consensus. Webinars were utilized to train BPCs to engage peers in best practices, and facilitate guideline dissemination. RESULTS: In Phase 1, 21 OLs were selected from 80 nominees. Sixteen attended a training workshop. In Phase 2, 486 chiropractors recommended 1126 potential BPCs, of which 133 were invited to participate and 112 accepted. CONCLUSIONS: OLs and BPCs were identified across Canada to enhance the uptake of research among chiropractors.

OBJECTIFS: Décrire le processus permettant de choisir et former les leaders d'opinion (LO) et collaborateurs des pratiques d'exemplaire (CPE) en chiropratique dans le but de favoriser l'adoption des pratiques d'excellence. MÉTHODOLOGIE: Lors de la première phase, on a désigné les LO au moyen d'une enquête transversale parmi les intervenants canadiens de la chiropratique. Un comité composé de dix membres a classé les candidats. Les candidats les mieux classés ont été invités à un atelier de formation. Lors de la deuxième phase, 7 200 chiropraticiens canadiens se sont soumis à une enquête nationale en ligne visant à désigner d'autres LO et CPE. Les noms recommandés ont été présélectionnés par les LO et le choix final s'est fait d'un commun accord. On s'est servi de webinaires pour former les LO à encourager leurs pairs à adopter des pratiques d'excellence et faciliter la diffusion des lignes directrices. RÉSULTATS: Lors de la première phase, on a choisi 21 LO parmi 80 candidats. Seize d'entre eux ont assisté à un atelier de formation. Lors de la deuxième phase, 486 chiropraticiens ont recommandé 1 126 LO potentiels, parmi lesquels 133 ont été invités à participer et 112 ont accepté. CONCLUSIONS: On a désigné des LO et CPE à l'échelle du pays pour favoriser l'adoption de la recherche parmi les chiropraticiens.

The effect of a lumbar support pillow on lumbar posture and comfort during a prolonged seated task.

BACKGROUND: Several risk factors exist for the development of low back pain, including prolonged sitting and flexed spinal curvature. Several investigators have studied lumbar support devices and spinal curvatures in sitting, however few have investigated a pain population and reported a quantitative measure of comfort. The purpose of the current project was to determine whether a lumbar support pillow, outfitted with a cut-out to accommodate the bulk of posterior pelvic soft tissue volume, is more effective than a standard chair in promoting a neutral spinal posture and improving subjective and objective measures of comfort in healthy individuals and patients with low back pain. METHODS: Twenty eight male participants with and without a history of low back pain sat in a standard office chair and in a chair with the lumbar support pillow for 30 minutes. Lumbar and thoracolumbar postures were measured through electromagnetic markers. Comfort was determined based on the least squares radius of centre of pressure shifting, measured at the buttock-chair interface as well as reported discomfort through visual analog scales. Chair support effects were assessed through ANOVA methods. The study was approved by the Canadian Memorial Chiropractic College research ethics board. RESULTS: There was a main effect of condition on lumbar posture (p = 0.006) and thoracolumbar posture (p = 0.014). In the lumbar region, the support and standard chair differed by 2.88° (95% CI; 1.01-4.75), with the lumbar support being closer to neutral than the standard chair. In the thoracolumbar region, the support and standard chair differed by -2.42° (95% CI; -4.22 to -0.62), with the standard chair being closer to neutral than the support device. The centre of pressure measure was significantly improved with the pillow (p = 0.017), however there were no subjective changes in comfort. CONCLUSIONS: A lumbar support pillow with a cut-out for the posterior pelvic tissues improved an objective measure of comfort in healthy individuals and patients with low back pain. Lumbar flattening was decreased and thoracolumbar curvature was increased. However, angular changes were small and future work is required to determine clinical relevance over the long term. TRIAL REGISTRATION: ClinicalTrials.gov, NCT00754585.

Effects of trunk muscle fatigue and load timing on spinal responses during sudden hand loading.

The purpose of this study was to investigate the responses of the spine during sudden loading in the presence of back and abdominal muscle fatigue, with a primary focus on the implications for spinal stability. Fifteen females were studied and each received sudden loads to the hands, at both known and unknown times. Participants received these loading trials (a) while rested, (b) with back muscle fatigue, and (c) with a combination of back and abdominal muscle fatigue. Measures were taken on the EMG activity of two trunk extensor and two abdominal muscles, and on the trunk angle and centre of pressure. A 3x2 Repeated Measures ANOVA was also performed. There were no preparations made prior to the perturbation even when it could be anticipated. However, the peak responses that followed were greater in the unexpected versus the expected condition. In addition, trunk muscle fatigue led to an increase in the baseline activity of the trunk muscles but no additional increase in activity just prior to loading. There was increased activation of both (opposing) muscle groups when only one muscle group was fatigued. Because the peak responses following the perturbation were enhanced in the unknown timing condition, preparations must have taken place prior to the anticipated perturbations, perhaps in other segments of the body that were not measured. Also, the load impact may not have been great enough to elicit large preparations. The heightened baseline activity with fatigue suggests that there may have been increased spinal stiffness whenever the spine was fatigued, and not just immediately prior to an impending perturbation. The increased activation of opposing muscle groups is evidence of increased cocontraction in response to fatigue, possibly to maintain stability with decreasing coordination.

Strength limitations to proper child safety seat installation: implications for child safety.

A majority of child safety restraints are misused in some manner, often leading to an increased risk of serious injury or death. It is possible that at least some instances of misuse are the result of biomechanical limitations during the installation process. Twenty-seven adult participants were trained and then monitored in three stages of child safety seat installation. All installations were done with an identical restraint system in the rear bench seat of a mocked-up minivan. EMG of 10 muscles, as well as trunk, shoulder, and wrist postures were analyzed. Peak maximum efforts were often required of the trunk extensor, forearm, and anterior shoulder muscles during the installation process. Routing and tightening of the seatbelt, as well as placing and securing the child into the seat were observed to be particularly difficult tasks. Many portions of the child safety seat installation process were found to be very physically demanding; some individuals may not be capable of performing these tasks correctly, thereby putting the child at greater risk in the motor vehicle.