Effects of School Backpacks on Spine Biomechanics During Daily Activities: A Narrative Review of Literature

Prevalence of spine pain among Tunisian children and adolescents and related factors

BACKGROUND

The prevalence of back and neck pain is common in children and adolescents, and in some series the numbers are alarming. Various risk factors have been identified, although some are controversial.

OBJECTIVE

To determine the prevalence of neck and back pain in children and adolescents and to investigate the potential association with various risk factors identified in the literature.

METHODS

We established a questionnaire targeting parents of children and adolescents aged between 6 and 18 years old in Tunisia. The recruitment of participants was done online using the Google Forms application. The questionnaire was divided into 2 parts: Part one collected the sociodemographics characteristics of the participants : age, gender, body mass index (BMI), exposure to passive smoking, the practice of a physical activity, puberty status and age at puberty if applicable, type and weight of the schoolbag, mean daily time spent on electronic devices, type of school the child attends (private/public), mode of transport from home to school, parental history of neck and/or back pain (mid or low back pain (LBP)), posture of the sitting position of the child, and finally whether the child reports neck/ back pain. The second part was aimed at parents whose child reported neck and/or back pain. We asked about the weekly frequency of neck/back pain, school absenteeism due to neck/back pain, whether it prevented the child from practicing physical activity and, finally, whether the child had ever seen a doctor/chiropractor/physiotherapist for their neck/back pain.

RESULTS

Eighty-eight children (45 females, 43 males) were enrolled. Mean age was 11.9 ± 3.8 years [6-18]. Mean BMI was 18.8 ± 4.2 [15.8-35.5]. Thirty-four (38.6%) were pubescent. Twenty-five (28.4%) children were exposed to passive smoking. Parental history of spine pain was found in 58% of cases. A poor sitting position was noted in n = 49 (55.7%). Mean daily screen time was 88.3 ± 75.56 min [0-360]. Prevalence of spine pain was 44% (n = 39) distributed as follows: neck pain (n = 21, 23.8%), mid back pain (n = 15, 17%), LBP (n = 26, 29.5%), neck, mid back and low back pain (n = 4, 4.5%) Professional help seeking for spine pain in children was reported by 15 participants (25.3%). Among them, 20.3% visited a physician and 5% consulted a chiropractor or physiotherapist. A significant correlation was found between spine pain and age (p = 0.006) and BMI (p = 0.006). A significant association was found between LBP and exposure to passive smoking, puberty status, type of school bag and poor posture. A positive parental history of spine pain was significantly associated with the presence of spine pain in their children with p = 0.053 (neck pain), p = 0.013 (back pain) and p < 0.00 (LBP) respectively. A significant association was found between the presence of spine pain and school absenteeism, participation in sports, consultation with a doctor or physiotherapist/chiropractor (p < 0.0001 respectively).

CONCLUSION

The prevalence of spinal pain was frequent in our series. A positive parental history of spinal pain, a bad posture while sitting, passive smoking, use of backpack, higher age and higher BMI were potential associated factors.

Pilot evaluation of the effectiveness of an ergonomics awareness educational programme addressed to middle-school children

BACKGROUND

Ergonomics programmes addressed to children fit the health-promoting schools (HPS) framework. Beyond the integration of ergonomics in curricula, an important aspect is the effectiveness of the programme. This pilot study aims to evaluate the effectiveness of the programme proposed to a sample of middle-school children (aged 10-13 years) of the metropolitan city of Cagliari.

METHODS

The programme was designed along the lines of the INAIL (Italian National Institute for Insurance against Accidents at Work) scheme and proposed to 260 children. It consisted of three phases: 1) assessment of students' background with a pre-intervention questionnaire (completed by 142 students); 2) teaching of the ergonomics training modules and evaluation of the weight of a sample of 160 backpacks, and of students' perception to be able to sit by putting their feet on the ground; 3) evaluation of conceptual understanding of ergonomics concepts with a post-intervention questionnaire (completed by 107 students out of the 142 students who completed phase 1).

RESULTS

There was a substantial improvement in the percentage of correct responses post-intervention, confirmed by the chi-square test, regarding concepts about ergonomics, backpack weight and handling. Most of the backpacks exceeded the maximum allowed value, and 20% of students were perceived to be unable to sit putting their feet on the ground.

CONCLUSIONS

The practical application of ergonomics pedagogy proved effective in the school setting and should be integrated into school curricula. The prevention technicians can offer a holistic approach, while the teachers are essential to implement the programme on a large scale. Effectiveness evaluation is necessary to guide resource allocation and implement and sustain the HPS approach. A tailored programme has a greater chance of reaching its target audience and maximizing effectiveness.

Backpack loading position and self-selected foot position as measured by foot tracings

BACKGROUND

It is known that even under static conditions a backpack wearer will need to make some adjustments to maintain postural stability. There is a paucity of research exploring the impact of altering the position of the feet with imposed loads of variable distance from the posterior midline.

OBJECTIVE

Therefore, the aim of this study was to determine if changes in the horizontal position of a fixed load when wearing a backpack affect specific variables derived from foot tracings of males and females standing with their self-selected natural feet position.

METHODS

150 healthy volunteer participants were instructed to adopt a natural stance across four conditions: Backpack with no weight, backpack with a weight (5% of body mass) placed at 0 cm, 20 cm, and 40 cm distance from the posterior body. Foot tracings were made for each condition. Base of Support (BoS), Feet Width (FW), and Feet Opening Angle (FOA) were calculated.

RESULTS

The BoS significantly decreased in loaded conditions (0 cm, 20 cm and 40 cm) compared to unloaded. This was supported by FW and FOA significant findings that once the load was imposed the response was to approximate the feet and reduce 'toeout'.

CONCLUSION

This reaction of people to reduce their BoS in response to added backpack load appears counter intuitive and raises the question of whether this is maladaptive. Clarification by further investigation will inform backpack wearers to counter this instinctive response to load and increase postural stability.

Reducing Back Exertion and Improving Confidence of Individuals with Low Back Pain with a Back Exosuit: A Feasibility Study for Use in BACPAC

OBJECTIVE

Low back pain (LBP) is hallmarked by activity limitations, especially for tasks involving bending. Back exosuit technology reduces low back discomfort and improves self-efficacy of individuals with LBP during bending and lifting tasks. However, the biomechanical efficacy of these devices in individuals with LBP is unknown. This study sought to determine biomechanical and perceptual effects of a soft active back exosuit designed to assist individuals with LBP sagittal plane bending. To understand patient-reported usability and use cases for this device.

METHODS

Fifteen individuals with LBP performed two experimental lifting blocks once with and without an exosuit. Trunk biomechanics were measured by muscle activation amplitudes, and whole-body kinematics and kinetics. To evaluate device perception, participants rated task effort, low back discomfort, and their level of concern completing daily activities.

RESULTS

The back exosuit reduced peak back extensor: moments by 9%, and muscle amplitudes by 16% when lifting. There were no changes in abdominal co-activation and small reductions maximum trunk flexion compared to lifting without an exosuit. Participants reported lower task effort, back discomfort, and concern about bending and lifting with an exosuit compared to without.

CONCLUSIONS

This study demonstrates a back exosuit not only imparts perceptual benefits of reduced task effort, discomfort, and increased confidence in individuals with LBP but that it achieves these benefits through measurable biomechanical reductions in back extensor effort. The combined effect of these benefits implies back exosuits might be a potential therapeutic aid to augment physical therapy, exercises, or daily activities.

Multi-Output Sequential Deep Learning Model for Athlete Force Prediction on a Treadmill Using 3D Markers

Reliable and innovative methods for estimating forces are critical aspects of biomechanical sports research. Using them, athletes can improve their performance and technique and reduce the possibility of fractures and other injuries. For this purpose, throughout this project, we proceeded to research the use of video in biomechanics. To refine this method, we propose an RNN trained on a biomechanical dataset of regular runners that measures both kinematics and kinetics. The model will allow analyzing, extracting, and drawing conclusions about continuous variable predictions through the body. It marks different anatomical and reflective points (96 in total, 32 per dimension) that will allow the prediction of forces (N) in three dimensions (Fx, Fy, Fz), measured on a treadmill with a force plate at different velocities (2.5 m/s, 3.5 m/s, 4.5 m/s). In order to obtain the best model, a grid search of different parameters that combined various types of layers (Simple, GRU, LSTM), loss functions (MAE, MSE, MSLE), and sampling techniques (down-sampling, up-sampling) helped obtain the best performing model (LSTM, MSE, down-sampling) achieved an average coefficient of determination of 0.68, although when excluding Fz it reached 0.92.

Survey on Video-Based Biomechanics and Biometry Tools for Fracture and Injury Assessment in Sports

This work presents a survey literature review on biomechanics, specifically aimed at the study of existent biomechanical tools through video analysis, in order to identify opportunities for researchers in the field, and discuss future proposals and perspectives. Scientific literature (journal papers and conference proceedings) in the field of video-based biomechanics published after 2010 were selected and discussed. The most common application of the study of biomechanics using this technique is sports, where the most reported applications are american football, soccer, basketball, baseball, jumping, among others. These techniques have also been studied in a less proportion, in ergonomy, and injury prevention. From the revised literature, it is clear that biomechanics studies mainly focus on the analysis of angles, speed or acceleration, however, not many studies explore the dynamical forces in the joints. The development of video-based biomechanic tools for force analysis could provide methods for assessment and prediction of biomechanical force associated risks such as injuries and fractures. Therefore, it is convenient to start exploring this field. A few case studies are reported, where force estimation is performed via manual tracking in different scenarios. This demonstration is carried out using conventional manual tracking, however, the inclusion of similar methods in an automated manner could help in the development of intelligent healthcare, force prediction tools for athletes and/or elderly population. Future trends and challenges in this field are also discussed, where data availability and artificial intelligence models will be key to proposing new and more reliable methods for biomechanical analysis.

Consistent inconsistencies in braking: a spatial analysis

The dynamic system that is the bipedal body in motion is of interest to engineers, clinicians and biological anthropologists alike. Spatial statistics is more familiar to public health researchers as a way of analysing disease clustering and spread; nonetheless, this is a practical approach to the two-dimensional topography of the foot. We quantified the clustering of the centre of pressure (CoP) on the foot for peak braking and propulsive vertical ground reaction forces (GRFs) over multiple, contiguous steps to assess the consistency of the location of peak forces on the foot during walking. The vertical GRFs of 11 participants were collected continuously via a wireless insole system (MoticonReGo AG) across various experimental conditions. We hypothesized that CoPs would cluster in the hindfoot for braking and forefoot for propulsion, and that braking would demonstrate more consistent clustering than propulsion. Contrary to our hypotheses, we found that CoPs during braking are inconsistent in their location, and CoPs during propulsion are more consistent and clustered across all participants and all trials. These results add to our understanding of the applied forces on the foot so that we can better predict fatigue failures and better understand the mechanisms that shaped the modern bipedal form.

Distribution and imaging characteristics of spina bifida occulta in young people with low back pain: a retrospective cross-sectional study

PURPOSE

Spina bifida occulta (SBO) is one of the most common congenital spinal deformities. Although many studies have demonstrated the influence of lumbosacral dysplasia on low back pain (LBP) in young athletes, there have been few studies on SBO among young people in other occupations. The purpose of this study is to investigate the distribution of SBO in young people with LBP and to classify SBO from the perspective of lamina development.

METHODS

The X-ray films of 148 young patients with LBP were analyzed to quantify the distribution of SBO and classify abnormal laminae.

RESULTS

Of the 148 patients, 93 (61.49%) had SBO: 83 cases involved S1 alone, 2 involved L5-S1, 5 involved S1-2, 2 involved S1-4, and 1 involved L4-S4. According to the degree of the defect, the patients with SBO were divided on the basis of five grades: 9 patients with grade I, 53 with grade II, 23 with grade III, and 8 with grade IV. The cases were classified by the shape of the laminae into 4 types: 15 cases of type a, 11 cases of type b, 37 cases of type c, and 30 cases of type d.

CONCLUSION

Among the young people with LBP that we surveyed, SBO is the most common lumbosacral dysplasia, which frequently involves the S1 segment. Most laminae in SBO are in the developmental stage of the spinous process, and an abnormal laminar growth direction and laminar stenosis are the most common laminar morphologies in SBO.

[The influence of backpack weight in school children: gait, muscle activity, posture and stability]

Hintergrund

Das tägliche Tragen eines schweren Schulrucksacks kann möglicherweise Haltungsstörungen hervorrufen, die sich auf das Gangbild und die Standstabilität der Kinder und Jugendlichen auswirken.

Ziel der Arbeit (Fragestellung)

Ziel der vorliegenden Studie war es, den Einfluss einer Rucksacklast von 4 kg auf das Gangbild und die Standstabilität bei Grundschulkindern zu analysieren.

Material und Methoden

In der prospektiven Arbeit wurde ein Kollektiv von zwölf Grundschulkindern zwischen 7 und 10 Jahren ohne neurologische oder orthopädische Probleme untersucht. Die Messungen beinhalteten eine klinische Untersuchung, eine dreidimensionale Ganganalyse mit elektromyografischen Aufzeichnungen und die Prüfung des ruhigen Stehens auf einer Kraftmessplatte.

Ergebnisse

Die Rucksacklast von durchschnittlich 15 % des Körpergewichts führte zu reduzierter Ganggeschwindigkeit, verkürzter Schrittlänge und verlängerter Doppelunterstützungsphase. Zudem kam es zu einer erhöhten Oberkörpervorneigung, Beckenkippung und Hüftbeugung. Auch die Muskelaktivität und Stabilität der Kinder wurde durch die erhöhte Traglast beeinflusst.

Diskussion

Schulrucksäcke mit einem Gewicht von 4 kg führten bei Grundschulkindern zu Änderungen von Gang, Muskelaktivität, Haltung und Standstabilität. Das Gewicht des Rucksacks verlagert den Körperschwerpunkt nach hinten und führt zur Instabilität. Dies wird beim Gehen durch eine vermehrte Oberkörpervorneigung, Beckenkippung nach vorne und vermehrte Hüftbeugung kompensiert. Die verminderte Paraspinalmuskelaktivität deutet darauf hin, dass der Rucksack passiv getragen wird. Dies könnte sich im Langzeitverlauf negativ auswirken.