The spinal posture of computing adolescents in a real-life setting

Thoracic spinal postures and mobility in patients with cervicogenic headache versus asymptomatic healthy controls: A longitudinal study

INTRODUCTION

Studies analyzing postures and mobility of the thoracic spine in the context of cervicogenic headache are missing. Insight in these parameters is needed since the cervical and thoracic spine are biomechanically related.

OBJECTIVE

To compare self-perceived optimal and habitual postures, active-assisted maximal range of motion, and repositioning error of the upper-thoracic and lower-thoracic spine between a cervicogenic headache-group and matched healthy control-group before and after a 30 min-laptop-task.

METHODS

A non-randomized longitudinal design was used to compare thoracic postures and mobility between 18 participants with cervicogenic headache (29-51 years) and 18 matched healthy controls (26-52 years). Outcomes were: self-perceived optimal and habitual postures, active-assisted maximal range of motion, and repositioning error of the upper-thoracic and lower-thoracic spine evaluated in sitting with a 3D-Vicon motion analysis system.

RESULTS

Habitual upper-thoracic postures in the cervicogenic headache-group were significantly (p = .04) less located toward the maximal range of motion for flexion compared to the control-group, self-perceived optimal upper-thoracic posture was significantly (p = .004) more extended in the cervicogenic headache-group compared to the control-group, and self-perceived optimal lower-thoracic posture could not be reestablished in the cervicogenic headache-group after the laptop-task (p = .009).

CONCLUSION

Thoracic postures differ between a cervicogenic headache-group and control-group. These differences were detected by expressing the habitual thoracic posture relative to its maximal range of motion, and by analyzing the possibility of repositioning the thoracic spine after a headache provoking activity. Longitudinal studies are needed to determine the contribution of these musculoskeletal dysfunctions to the pathophysiology of cervicogenic headache.

Neck and shoulder strains under various head flexing positions while standing and sitting with and without back support for male and female smartphone users

This study recruited 30 young participants (15 men and 15 women) to examine the smartphone usage patterns in three postures (standing, supported sitting, and unsupported sitting) and at five head angle (HA) positions (0°-40°). Cervical erector spinae (CES) and upper trapezius (UTZ) muscle activity, neck flexion (NF), gaze angle (GA), viewing distance (VD), and discomfort scores were collected. Results showed that HA and posture almost affected all responses, while CES muscle activity, NF, and VD differed between sexes. Strain in the neck and shoulder region increased with HA increase. Particularly, when the HA exceeded 20°, the discomfort scores considerably increased. Unsupported sitting should be avoided during smartphone use because of relatively poor responses in all variables. However, both standing and supported sitting have their respective benefits. Sex-related differences were typically observed in the standing position, with women tending to have lower NF but higher CES muscle activity compared with men.Practitioner summary: Although smartphones have become daily necessities, the overall quantitative neck and shoulder strain of using smartphones in different postures is rarely evaluated. We suggest that maintaining the HA within 20° is recommended because of relatively low load on the neck and shoulders. An unsupported sitting should be avoided during smartphone use.

Gender differences in neck muscle activity during near-maximum forward head flexion while using smartphones with varied postures

Women frequently express heightened neck discomfort even though they exhibit smaller neck flexion (NF) during smartphone use. Differences in natural posture while using smartphones may result in varying muscle activation patterns between genders. However, no study focused on this issue. This study investigated the influence of gender on neck muscle activity and NF when using smartphones, ranging from slight (20°) to nearly maximal forward head flexion, across different postures. We analyzed smartphone usage patterns in 16 men and 16 women and examined these behaviors across different scenarios: standing, supported sitting, and unsupported sitting, at 20°, 30°, 40°, and the maximum head angles. During data collection, muscle activity was measured, expressed as a percentage of the maximum voluntary contraction (%MVC), in the cervical erector spinae (CES) and upper trapezius (UTZ), along with NF. Results show significant influences of gender, head angle, and posture on all measures, with notable interactions among these variables. Women displayed higher muscle activities in CES and UTZ, yet exhibited lesser NF, while using smartphones in both standing (12.3%MVC, 10.7% MVC, and 69.0°, respectively) and unsupported sitting (10.8%MVC, 12.3%MVC, and 71.8°, respectively) compared to men (standing: 9.5%MVC, 8.8%MVC, and 76.1°; unsupported sitting: 9.7%MVC, 10.8%MVC, and 76.1°). This study provides a potential rationale for gender-related disparities in injury outcomes, emphasizing that women experience higher neck and shoulder discomfort level, despite their smaller NF during smartphone use, as found in previous research. Additionally, the cervical flexion-relaxation phenomenon may occur when the head angle exceeded 40°. The near-maximum head angle during smartphone use might induce the cervical flexion-relaxation phenomenon, potentially aggravating neck issues. We recommend limiting smartphone usage postures that exceed the near-maximum head angle, as they are commonly adopted by individuals in the daily smartphone activities.

Investigation of Joint Position Sense and Balance in Individuals With Chronic Idiopathic Neck Pain: A Cross-Sectional Study

OBJECTIVE

The aim of this study was to determine the relationship between joint position sense and static and dynamic balance in female patients with chronic neck pain compared with healthy controls.

METHODS

The study sample comprised 25 female patients with chronic neck pain and 25 healthy (asymptomatic) female controls. Pain severity with the visual analog scale, joint position sense with the laser pointer method, static balance with the Single-Leg Balance Test, and dynamic balance with the Y Balance Test were assessed.

RESULTS

The deviation in cervical joint position sense was greater in extension (P < .001), right rotation (P < .001), and left lateral rotation (P < .05) in the patients with chronic neck pain compared with the healthy controls. The results of the patients with chronic neck pain were worse than the healthy controls in the Single-Leg Balance Test with both eyes open (P < .05) and eyes closed (P < .05). The patients with chronic neck pain had worse dynamic balance only in the anterior direction reach of the left leg (P < .05).

CONCLUSION

Cervical joint position sense and static balance were worse in female patients with chronic idiopathic neck pain when compared with asymptomatic controls. Dynamic balance in all other directions except for the anterior direction was not negatively affected in individuals with chronic idiopathic neck pain.

Factors associated with intensity and frequent low back pain in high school students

Introduction: Low back pain is frequent among schoolchildren and the variables related to high intensity and high back frequency are important predictors for the increase of such complaints in adulthood. Objective: To determine the high intensity and high frequency of low back pain and its associated factors in high school students. Methods: This cross-sectional study included 760 students (319 boys and 441 girls) who reported low back pain. Demographic, socioeconomic, electronic devices, habitual physical activity practice, mental health, and high frequency and high intensity low back pain data were collected. Descriptive analyzes and bivariate and multivariate logistic regressions were used. Results: Of the total number of subjects with low back pain, 14.6% reported high frequency of pain, being 36.9% boys and 63.1% girls, while 42.6% reported high intensity, being 35.8% boys and 47.2% girls. The variables associated with the high frequency of low back pain were altered mental health, posture lying on the use of tablet, time of daily use of the cell phone and distance of the screen to the eyes of the computer user, while the female sex, mental health problem, posture lying on the use of cell phone and the distance of the screen to the eyes of the computer user with severe intensity of low back pain. Conclusion: The demographic factors and related to the use of electronic devices were associated with high intensity and high frequency of low back pain.

Increased Computer Use is Associated with Trunk Asymmetry That Negatively Impacts Health-Related Quality of Life in Early Adolescents

PURPOSE

This study aimed to investigate the effects of trunk asymmetry on the health-related quality of life of early adolescents and to identify daily activities that were associated with trunk asymmetry in this cohort.

METHODS

This study included 200 early adolescents (52 male and 148 female) aged 10 to 14 years in Hong Kong. Among them, 100 adolescents were considered to have trunk asymmetry with angle of trunk rotation ≥5° and one or more physical signs on visual inspection. The 36-Item Short Form Health Survey was used to measure the eight scales under the physical and mental domains of the health-related quality of life. The adolescents reported their average daily durations spent (1) using a computer; (2) using a smartphone; (3) watching television, videos or DVDs; (4) doing homework; and (5) doing physical exercise. Independent samples t-tests, chi-square (χ 2) tests or Mann-Whitney U-tests were performed to compare the health-related quality of life and the average daily duration of daily activities between early adolescents with and without trunk asymmetry. Logistic regression was performed to investigate the odds ratios of daily activities for trunk asymmetry.

RESULTS

Compared with early adolescents without trunk asymmetry, those with trunk asymmetry had a lower health-related quality of life in some of the physical domains, namely, bodily pain and general health, and all mental domains, namely, vitality (energy/fatigue), social functioning, role limitation due to emotional problems and mental health (p < 0.05). Use of computer was found to be significantly associated with trunk asymmetry in early adolescents (OR = 1.63, 95% CI [1.23, 2.14]).

CONCLUSION

Our results indicate that increased computer use is associated with trunk asymmetry, which negatively impacts the health-related quality of life in early adolescents.

Perspectives of spinal health within the school setting in a South African rural region: A qualitative study

BACKGROUND

Spinal pain is one of the leading causes of morbidity globally. There is an increase in the number of children and adolescents who experience spinal pain and the lifetime prevalence of adolescent spinal pain varies between countries. In Africa, one in two adolescents experiences spinal pain and the prevalence is increasing.

OBJECTIVE

This study reports on the knowledge and perspectives of school-attending children, adolescents, teachers, and parents/guardians regarding spinal health.

METHODS

We conducted a descriptive qualitative case study with an interpretative and phenomenological approach. Data coding, management and analysis was done using ATLAS.ti computer software.

RESULTS

Ninety-three participants (66 women and 27 men) were enrolled in the study. The barriers associated with students' spinal health were multifactorial, including low levels of physical activity, dangerous gameplay, sports risks, poor ergonomics, school bags, insufficient knowledge, and pregnancy risks. Participants proposed strategies to improve spinal health including the provision of students' lockers, advice on appropriate school bag types, embedding spinal education in the curriculum, general advocacy for spinal health, and integration of technology in teaching and learning.

CONCLUSION

There is a need for further engagement on school-based spinal health promotion programs that consider local socio-economic, educational, and cultural factors.

Sitting Posture during Prolonged Computer Typing with and without a Wearable Biofeedback Sensor

Prolonged sitting combined with an awkward posture might contribute to the increased risks of developing spinal pain. Maintaining an upright sitting posture is thus often suggested, especially nowadays when people spend longer periods in the sitting posture for occupational or leisure activities. Many types of assistive devices are commercially available to help computer users maintain an upright sitting posture. As the technology advances, wearable sensors that use microelectromechanical technology are designed to provide real-time biofeedback and promote adjusting posture actively. However, whether such wearable biofeedback sensors could assist adjusting sitting posture in computer users during prolonged typing remains unknown. This study aimed to investigate the effects of a wearable biofeedback sensor on maintaining an upright sitting posture. Twenty-one healthy young adults were recruited and performed a 1-h computer typing task twice, with and without using the active biofeedback device. The sagittal spinal posture during computer typing was measured using a three-dimensional motion analysis system. Using the wearable biofeedback sensor significantly decreased the neck flexion (p < 0.001), thoracic kyphotic (p = 0.033), and pelvic plane (p = 0.021) angles compared with not using the sensor. Computer users and sedentary workers may benefit from using wearable biofeedback sensors to actively maintain an upright sitting posture during prolonged deskwork.

A Two Joint Neck Model to Identify Malposition of the Head Relative to the Thorax

Neck pain is a frequent health complaint. Prolonged protracted malpositions of the head are associated with neck pain and headaches and could be prevented using biofeedback systems. A practical biofeedback system to detect malpositions should be realized with a simple measurement setup. To achieve this, a simple biomechanical model representing head orientation and translation relative to the thorax is introduced. To identify the parameters of this model, anthropometric data were acquired from eight healthy volunteers. In this work we determine (i) the accuracy of the proposed model when the neck length is known, (ii) the dependency of the neck length on the body height, and (iii) the impact of a wrong neck length on the models accuracy. The resulting model is able to describe the motion of the head with a maximum uncertainty of 5 mm only. To achieve this high accuracy the effective neck length must be known a priory. If however, this parameter is assumed to be a linear function of the palpable neck length, the measurement error increases. Still, the resulting accuracy can be sufficient to identify and monitor a protracted malposition of the head relative to the thorax.

Lower spinal postural variability during laptop-work in subjects with cervicogenic headache compared to healthy controls

Spinal postural variability (SPV) is a prerequisite to prevent musculoskeletal complaints during functional tasks. Our objective was to evaluate SPV in cervicogenic headache (CeH) since CeH is characterized by such complaints. A non-randomized repeated-measure design was applied to compare SPV between 18 participants with reporting CeH aged 29–51 years, and 18 matched controls aged 26–52 years during a 30-min-laptop-task. Habitual spinal postures (degrees) of the cervical, thoracic and lumbar spine were analysed using 3D-Vicon motion analysis. SPV, to express variation in mean habitual spinal posture, was deducted from the postural analysis. Mean SPV of each spinal segment was lower in the CeH-group compared to the control-group. Within the CeH-group, SPV of all except one spinal segment (lower-lumbar) was higher compared to the group’s mean SPV. Within the control-group, SPV was more comparable to the group’s mean SPV. SPV differed between groups. Averaging data resulted in decreased SPV in the CeH-group compared to the control-group during the laptop-task. However, the higher within-group-SPV in the CeH-group compared to the group’s mean SPV accentuated more postural heterogeneity. It should be further determined if addressing individual SPV is a relevant intervention.

Neck pain associated with smartphone overuse: cross-sectional report of a cohort study among office workers

PURPOSE

The aim of the current study was to investigate the extent of smartphone use, possible correlation with neck pain and/or psychological impairment in office workers.

METHOD

A convenience sample of 1,602 office workers who were using smartphone for prolonged periods (≥ 4 years) participated in a cross-sectional report of a cohort study, assessing demographic, abnormal symptoms of pain in the neck, physical activity, and psychological behavior characteristics. Participants were assessed using a short version of the Smartphone Addiction Scale (SAS-SV), Depression, Anxiety and Stress Scales (DASS-42) questionnaire, as well as International Physical Activity Questionnaire-Short Form (IPAQ-SF). Multiple logistic regression model was conducted to evaluate the adjusted effect of smartphone overuse on nuchal symptoms.

RESULTS

The prevalence of neck pain among the office workers was 30.1%. Significantly more female (33.3% vs. 24.5%) and younger (42.2 vs. 43.2 years) employees reported to have neck pain. Overall in 326 (20.3%, 95% CI: 18.4%-22.4%) of studied subjects had, SAS score ≥ 31 and ≥ 33 for male and females, respectively, and so smartphone overuse (SO) was diagnosed. The results of multiple logistic regression model revealed that those with SO were approximately 6 times more likely to have neck pain (95% CI: 4.44-8.09, P < 0.001).

CONCLUSIONS

Smartphone overuse in office workers significantly increases the chance of neck pain by 6 times. Hence SO has been associated with, not only somatic complaints, but also psychological distress such as anxiety, stress, and depression. This may necessitate adherence to neck-school, when smartphone use is associated with neck pain.

Prevalence of low back pain in young Brazilians and associated factors: Sex, physical activity, sedentary behavior, sleep and body mass index

BACKGROUND

Low back pain (LBP) has become increasingly common, but the prevalence of this complaint and associated factors in young people remains controversial.

OBJECTIVE

This study aimed to identify the prevalence of LBP and to explore the existence of associated factors (sex, physical activity, sedentary lifestyle, sleep, body mass index and waist circumference).

METHODS

This study considered all complaints of the lumbar region (acute or chronic) as LBP, which can irradiate to the backside and legs, lasting a minimum of 24 hours. Youngsters aged 15 to 18 years from a school in the south of Brazil were evaluated. Descriptive statistics was used, in particular Chi-square, Mann-Whitney U tests and binary logistic regression. A significance level of p< 0.05 was adopted.

RESULTS

A total of 330 youngsters answered a questionnaire and had their anthropometric measurements measured (response rate 84%). The prevalence of LBP in the present was 30%, quarterly 63% and throughout life 77%. There was a significant association between LBP and sex: girls have an increased risk of LBP in the last three-month period (PR = 1.3, 95% CI 1.06-1.56) and throughout life (PR = 1.2, 95% CI 1.04-1.43). The practice of physical activities was also associated with LBP, but as a protection factor in the present and in the last three-month period (PR = 0.7, 95% CI 0.47-0.90). Physical education at school has demonstrated a protective factor regarding LBP throughout life (PR = 0.9, 95% CI 0.77-0.97). Most of the students did not comply with recommendations related to sleep and time spent doing activities in front of a screen, and no association of these factors with LBP was detected. This exposure (physical activity, sleep time, sedentarism) did not present significant association with LBP when adjusted by the confusion factors (sex, age, BMI).

CONCLUSIONS

Youngsters reported a high prevalence of LBP. Girls were at greater risk of LBP than boys. It is recommended that prevention strategies focus on the practices of physical activities and scholar physical education. No association of LBP with sedentary lifestyle (TV and computer use time, sleep time), anthropometric measures and sleeping duration was observed.

Intrarater and Interrater Reliability of Angular Measures Using TEMPLO Two-dimensional Motion Analysis Software

OBJECTIVE

The purpose of this study was to assess the intrarater and interrater reliability of marking 2 angles with the TEMPLO software and to provide relevant information for clinical practice.

METHODS

A prospective test-retest study has been conducted. Four raters took measures on 2 days, with 2 weeks in between. Craniovertebral angle and trunk forward lean were drawn on 22 video frames using TEMPLO. Reliability was examined using intraclass correlation coefficients including standard errors of measurement and minimal detectable change values as measures of precision expressed in the unit of the test (°).

RESULTS

Intraclass correlation coefficients for intrarater and interrater reliability ranged from 0.98 to 1.00. Standard errors of measurement and minimal detectable change values ranged from 0.4° to 0.8° and 0.8° to 2.3°, respectively.

CONCLUSION

These results indicate excellent reliability for craniovertebral angle and trunk forward lean assessed with TEMPLO software. Changes exceeding 2.3° may be expected to fall outside the test's variability.

Effects of biofeedback postural training on pre-existing low back pain in static-posture workers

BACKGROUND

Many studies report a relationship between poor static posture (SP) and low back pain (LBP). This study examined the effects of a biofeedback postural training program on pre-existing LBP, changes to level of physical activity and workability in participants.

OBJECTIVE

To determine if static posture training with biofeedback alleviates LBP.

METHODS

The control group wore a pedometer to track level of physical activity and the experimental group wore the postural training device, Lumo Lift, for three weeks. Participants completed the Cornell Musculoskeletal Discomfort Questionnaire (CMDQ) and completed pre- and post-intervention side-view pictures to evaluate changes in posture. Participants were predominately-sedentary work environment (N= 31; 13 men, 18 women; age = 33.1 ± 13.3 years; height = 170.2 ± 9.7 cm; mass = 71.6 ± 17.5 kg).

RESULTS

LBP discomfort was statistically significant when comparing pretest and posttest CMDQ mean score in all subjects [F(1, 18) = 6.25, p= 0.02]. There was no significant evidence of reducing LBP experience and LBP interference at work when comparing all subjects. There was no statistical difference in level of physical activity by analyzing average steps between the experimental and control groups (95% CI =-1040.4-1845.4, p= 0.57).

CONCLUSIONS

Postural training with biofeedback application helps with LBP management by decreasing level of LBP discomfort. People with LBP should be aware of their static posture and develop good muscle strength and endurance in order to maintain performance at work, school, or sports.

Immediate effects of real-time postural biofeedback on spinal posture, muscle activity, and perceived pain severity in adults with neck pain

BACKGROUND

Previous studies have investigated various types of postural biofeedback devices on different body regions to improve posture; however, they focused only on healthy adults without a history of chronic musculoskeletal disorders. In addition, those postural biofeedback devices used in previous studies are often designed for experimental research. The designs are usually bulky with many wires, which is not practical for everyday use.

RESEARCH QUESTION

The aim of this study was to determine the immediate effect of a commercially available real-time postural biofeedback device on spinal posture, muscle activity, and perceived pain severity in adults with neck pain.

METHODS

21 adults who had chronic or recurrent nonspecific neck pain for more than 3 months and whose pain was induced or aggravated by prolonged computer work were enrolled in this study. Spinal posture (head tilt, neck flexion, cervical and thoracic angles), muscle activity (cervical erector spinae, upper trapezius, and thoracic erector spinae), and self-reported neck and shoulder pain were measured during computer typing tasks, with and without biofeedback.

RESULTS

Compared with the non-biofeedback condition, the biofeedback condition significantly decreased neck flexion, upper cervical, and lower thoracic angles and lowered the activity of the cervical erector spinae. Self-reported neck pain was not influenced by the application of biofeedback, but significantly increased over the 1-hour typing task.

SIGNIFICANCE

The application of a commercially available wearable real-time biofeedback device improves sitting posture and reduces muscular activity in adults with nonspecific neck pain during computer work. Future studies should examine the long-term effects of wearable real-time postural biofeedback devices for prevention and management of neck pain.

The amount of postural change experienced by adolescent computer users developing seated -related upper quadrant musculoskeletal pain

BACKGROUND

Improved techniques of measuring sitting posture have not led to a more comprehensive understanding of poor posture, nor its association with pain. There is also an evidence gap regarding critical thresholds of sitting postural change over time related to pain production. This paper describes postural angle changes over a 12-month period, and describes the process of placing defensible cut-points in the angle change data, to better understand associations between posture change over time, and onset of upper quadrant musculoskeletal pain (UQMP).

METHODS

This paper reports on data captured at baseline and 12-month follow-up, in adolescents in school using computers. Four sitting postural angles, head flexion (HF), neck flexion (NF), craniocervical angle (CCA) and trunk flexion (TF), and self-reported seated UQMP in the previous month were captured at each time-point. Research questions were: 1) What is the magnitude and direction of change in each postural angle over 12 months? 2) What are best cut-points in the continuous posture change distribution to most sensitively test the association between posture change and UQMP? 3) Is gender-specific cut-points required? The 12-month posture angle change data was divided into quintiles (0-20th%; 21-40^th%, 41-60^th%, 61-80^th%, >80^th%), and the odds of UQMP occurring in each posture change quintile were calculated using logistic regression models.

RESULTS

Two hundred and eleven students participated at baseline, of which 153 were followed-up at one year. Both males and females with postural change into extension (which represents lesser flexion range) were more at risk for the development of UQMP, than any other group. The best cut-point for HF was 40^th% (≤-3.9°), NF was 20th% (≤-2.9°) and TF was 40^th% (≤-1.1°). For CCA however, change at or beyond 40^th % for extension or beyond 60% for flexion was associated with UQMP.

CONCLUSIONS

Identification of critical postural angle change cut-points assists in considering the pain-producing mechanisms for adolescents using desk top computers.

The Influence of Natural Head Position on the Cervical Sagittal Alignment

Introduction

This study investigated the relationship between the parameters related to the natural head position and cervical segmental angles and alignment of patients with neck pain.

Material and Methods

The lateral radiographs of the cervical spine were collected from 103 patients and were used to retrospectively analyze the correlation between the natural head position, cervical local sagittal angles, and alignment. Sagittal measurements were as follows: cervical curvature classification, slope of McGregor's line (McGS), local sagittal angles (C0–C2 angle, C2–C5 angle, C5–C7 angle, and C2–C7 angle), T1 slope, center of gravity of the head to sagittal vertical axis (CG–C7 SVA), and local sagittal alignment (C0–C2 SVA and C2–C7 SVA).

Results

McGS was significantly correlated to C0–C2 angle (r = 0.57), C0–C2 SVA (r = −0.53), C2–C7 SVA (r = −0.28), and CG–C7 SVA (r = −0.47). CG–C7 SVA was also significantly correlated to curvature type (r = 0.27), C5–C7 angle (r = −0.37), and C2–C7 angle (r = −0.39).

Conclusions

A backward shift with an extended head position may accompany a relatively normal curvature of the cervical spine. The effect of posture control in relieving abnormal mechanical state of the cervical spine needs to be further confirmed by biomechanical analysis.

Pain, pain intensity and pain disability in high school students are differently associated with physical activity, screening hours and sleep

Background

Studies exploring the association between physical activity, screen time and sleep and pain usually focus on a limited number of painful body sites. Nevertheless, pain at different body sites is likely to be of different nature. Therefore, this study aims to explore and compare the association between time spent in self-reported physical activity, in screen based activities and sleeping and i) pain presence in the last 7-days for 9 different body sites; ii) pain intensity at 9 different body sites and iii) global disability.

Methods

Nine hundred sixty nine students completed a questionnaire on pain, time spent in moderate and vigorous physical activity, screen based time watching TV/DVD, playing, using mobile phones and computers and sleeping hours. Univariate and multivariate associations between pain presence, pain intensity and disability and physical activity, screen based time and sleeping hours were investigated.

Results

Pain presence: sleeping remained in the multivariable model for the neck, mid back, wrists, knees and ankles/feet (OR 1.17 to 2.11); moderate physical activity remained in the multivariate model for the neck, shoulders, wrists, hips and ankles/feet (OR 1.06 to 1.08); vigorous physical activity remained in the multivariate model for mid back, knees and ankles/feet (OR 1.05 to 1.09) and screen time remained in the multivariate model for the low back (OR = 2.34. Pain intensity: screen time and moderate physical activity remained in the multivariable model for pain intensity at the neck, mid back, low back, shoulder, knees and ankles/feet (Rp² 0.02 to 0.04) and at the wrists (Rp² = 0.04), respectively. Disability showed no association with sleeping, screen time or physical activity.

Conclusions

This study suggests both similarities and differences in the patterns of association between time spent in physical activity, sleeping and in screen based activities and pain presence at 8 different body sites. In addition, they also suggest that the factors associated with the presence of pain, pain intensity and pain associated disability are different.

Gender difference in mobile phone use and the impact of digital device exposure on neck posture

This cross-sectional study aimed to identify gender differences in the cervical postures when young adults were using mobile phones, as well as the correlations between the postures and the digital devices use (computer and mobile phone). Questionnaires regarding the habits of computer and mobile phone use were administrated to 429 subjects aged from 17 to 33 years old (19.75 ± 2.58 years old). Subjects were instructed to stand habitually and use a mobile phone as in daily life; the sagittal head and cervical postures were measured by head flexion, neck flexion angle and gaze angle. Male participants had a significantly larger head flexion angle (96.41° ± 12.23° vs. 93.57° ± 12.62°, p  =  0.018) and neck flexion angle (51.92°  ±  9.55° vs. 47.09° ± 9.45°, p  <  0.001) than females. There were significant differences in head (F  =  3.62, p  =  0.014) and neck flexion (F  =  3.99, p  =  0.009) between different amounts of computer use. Practitioner Summary: We investigated possible gender differences in head and neck postures of young adults using mobile phones, as well as the potential correlations between these postures and digital device use. We found that males displayed larger head and neck flexion angles than females, which were associated with the amount of computer use.

Wrist Hypothermia Related to Continuous Work with a Computer Mouse: A Digital Infrared Imaging Pilot Study

Computer work is characterized by sedentary static workload with low-intensity energy metabolism. The aim of our study was to evaluate the dynamics of skin surface temperature in the hand during prolonged computer mouse work under different ergonomic setups. Digital infrared imaging of the right forearm and wrist was performed during three hours of continuous computer work (measured at the start and every 15 minutes thereafter) in a laboratory with controlled ambient conditions. Four people participated in the study. Three different ergonomic computer mouse setups were tested on three different days (horizontal computer mouse without mouse pad; horizontal computer mouse with mouse pad and padded wrist support; vertical computer mouse without mouse pad). The study revealed a significantly strong negative correlation between the temperature of the dorsal surface of the wrist and time spent working with a computer mouse. Hand skin temperature decreased markedly after one hour of continuous computer mouse work. Vertical computer mouse work preserved more stable and higher temperatures of the wrist (>30 °C), while continuous use of a horizontal mouse for more than two hours caused an extremely low temperature (<28 °C) in distal parts of the hand. The preliminary observational findings indicate the significant effect of the duration and ergonomics of computer mouse work on the development of hand hypothermia.

Photographic measurement of head and cervical posture when viewing mobile phone: a pilot study

PURPOSE

With the dramatic growth of mobile phone usage, concerns have been raised with regard to the adverse health effects of mobile phone on spinal posture. The aim of this study was to determine the head and cervical postures by photogrammetry when viewing the mobile phone screen, compared with those in neutral standing posture.

METHODS

A total of 186 subjects (81 females and 105 males) aged from 17 to 31 years old participated in this study. Subjects were instructed to stand neutrally and using mobile phone as in daily life. Using a photographic method, the sagittal head and cervical postures were assessed by head tilt angle, neck tilt angle, forward head shift and gaze angle.

RESULTS

The photographic method showed a high intra-rater and inter-rater reliability in measuring the sagittal posture of cervical spine and gaze angle (ICCs ranged from 0.80 to 0.99). When looking at mobile phone, the head tilt angle significantly increased (from 74.55° to 95.22°, p = 0.000) and the neck angle decreased (from 54.68° to 38.77°, p = 0.000). The forward head posture was also confirmed by the significantly increased head shift (from 10.90 to 13.85 cm, p = 0.000). The posture assumed in mobile phone use was significantly correlated with neutral posture (p < 0.05). Males displayed a more forward head posture than females (p < 0.05). The head tilt angle was positively correlated with the gaze angle (r = 0.616, p = 0.000), while the neck tilt angle was negatively correlated with the gaze angle (r = -0.628, p = 0.000).

CONCLUSIONS

Photogrammetry is a reliable, quantitative method to evaluate the head and cervical posture during mobile phone use. Compared to neutral standing, subjects display a more forward head posture when viewing the mobile phone screen, which is correlated with neutral posture, gaze angle and gender. Future studies will be needed to investigate a dose-response relationship between mobile phone use and assumed posture.

The relationship between sitting posture and seated-related upper quadrant musculoskeletal pain in computing South African adolescents: A prospective study

BACKGROUND

There is evidence that consistent sitting for prolonged periods is associated with upper quadrant musculoskeletal pain (UQMP). It is unclear whether postural alignment is a significant risk factor.

OBJECTIVE AND DESIGN

The aim of the prospective study (2010-2011) was to ascertain if three-dimensional sitting postural angles, measured in a real-life school computer classroom setting, predict seated-related UQMP.

METHOD

Asymptomatic Grade 10 high-school students, aged 15-17 years, undertaking Computer Application Technology, were eligible to participate. Using the 3D Posture Analysis Tool, sitting posture was measured while students used desk-top computers. Posture was reported as five upper quadrant angles (Head flexion, Neck flexion; Craniocervical angle, Trunk flexion and Head lateral bending). The Computer Usage Questionnaire measured seated-related UQMP and hours of computer use. The Beck Depression Inventory and the Multidimensional Anxiety Scale for Children assessed psychosocial factors. Sitting posture, computer use and psychosocial factors were measured at baseline. UQMP was measured at six months and one-year follow-up.

RESULTS

211, 190 and 153 students participated at baseline, six months and one-year follow-up respectively. 34.2% students complained of seated-related UQMP during the follow-up period. Increased head flexion (HF) predicted seated-related UQMP developing over time for a small group of students with pain scores greater than the 90th pain percentile, adjusted for age, gender, BMI, computer use and psychosocial factors (p = 0.003). The pain score increased 0.22 points per 1° increase in HF.

CONCLUSIONS

Classroom ergonomics and postural hygiene should therefore focus on reducing large HF angles among computing adolescents.