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Print version ISSN 1413-3555
Rev. bras. fisioter. vol.16 no.2 São Carlos Mar./Apr. 2012 Epub Apr 19, 2012
Efeitos de um programa educacional de cuidados com a coluna sobre o nível de conhecimento de escolares brasileiros quanto à prevenção de dor na coluna vertebral
Fabiana A. FoltranI; Roberta F. C. MoreiraI; Mariana O. KomatsuII; Mariana F. FalconiII; Tatiana O. SatoI,II
IPostgraduate Program in Physical Therapy, Universidade Federal de São Carlos (UFSCar), São Carlos, SP, Brazil
IIPhysical Therapy Department, UFSCar, São Carlos, SP, Brazil
BACKGROUND: Children are often exposed to ergonomic risk factors at school. Thus, the school is a potential environment for developing musculoskeletal disorders and implementing back care programs.
OBJECTIVES: To evaluate the effect of an educational program on schoolchildren's knowledge regarding back pain prevention.
METHODS: 392 students from 4th to 8th grade from a Brazilian state school took part in the study; 114 students (30%) were evaluated at follow-up. The back care program included pre- and post-intervention assessments and a follow-up assessment, as well as theoretical and practical lessons. The time interval between the pre- and post-intervention assessments was 9 weeks, and between the post-intervention and follow-up assessments, it was 2 years. Statistical analysis included non-parametric ANOVA tests. Significance level was set at 5% (p<0.05).
RESULTS: There was a significant increase (p<0.001) between pre- (3.6±2.9) and postintervention (7.5±2.2) scores and a significant decrease in the follow-up score (5.1±2.5). However, the follow-up score was still significantly higher (p<0.001) than the pre-intervention score. The rate of correct answers in the post-intervention assessment increased for all questions, and some of them were still high at follow-up. Significant differences were identified for the comparison between grades, with the 8th grade being significantly different from the other grades.
CONCLUSION: The back care program showed an increase in the level of knowledge of Brazilian schoolchildren. Two years after the intervention, students still retained ergonomic concepts. Although the program has limitations, theoretical knowledge acquisition is the first step towards adopting healthy postural habits to prevent back pain. Registration number: ACTRN12610000703000.
Keywords: posture; intervention studies; primary prevention; students; physical therapy.
CONTEXTUALIZAÇÃO: As crianças estão expostas a um conjunto de fatores de risco ergonômicos na fase escolar. Tais fatores tornam a escola um ambiente propício ao desenvolvimento de alterações musculoesqueléticas, assim como para a implementação de programas de cuidados com a coluna vertebral.
OBJETIVO: Avaliar os efeitos de um programa educacional de cuidados com a coluna sobre o nível de conhecimento de escolares brasileiros quanto à prevenção de dor na coluna vertebral.
MÉTODOS: Trezentos e noventa e dois estudantes da 4ª à 8ª série de uma escola estadual participaram do estudo, sendo que 114 deles (30%) foram avaliados no follow up. O programa foi composto por avaliações pré, pós-intervenção e follow up, por aulas teóricas e práticas. O intervalo entre as avaliações pré e pós-intervenção foi de nove semanas e, entre a avaliação pré e o follow up, foi de dois anos. A análise estatística incluiu ANOVA não-paramétrica e o nível de significância foi de 5%.
RESULTADOS: Houve diferença significativa no nível de conhecimento (p<0,001) entre as avaliações inicial (3,6±2,9), final (7,5±2,2) e no follow up (5,1±2,5), sendo que a pontuação no follow up foi significativamente superior à do pré-teste. Foi encontrada diferença significativa entre as séries, sendo que a 8ª série atingiu pontuação maior que as demais (p<0,05).
CONCLUSÃO: O programa preventivo proporcionou aumento no nível de conhecimento dos estudantes, mesmo após dois anos de sua implementação. Embora o programa tenha limitações, a aquisição de conhecimento é o primeiro passo para a adoção de hábitos posturais saudáveis para a prevenção de dores na coluna vertebral. Registro de ensaio clínico: ACTRN12610000703000.
Palavras-chave: postura; estudos de intervenção; prevenção primária; estudantes; fisioterapia.
The prevalence of back pain among children and adolescents varies between 3 and 74%1-5. This variation can be attributed to the population and the diagnostic criteria considered6-8. During school years, children spend one third of their waking hours at school9, an environment that can expose them to ergonomic risk factors including carrying heavy backpacks, sitting postures for prolonged periods, and inadequate furniture10-13. Thus, the school is a potential environment for developing musculoskeletal disorders, as well as implementing back care programs14.
Various postural deviations, especially of the spine, originate during childhood and adolescence12,15-16, which is a period of rapid musculoskeletal development (growth spurt) and when the spine is more susceptible to deformities17. Some authors report a high prevalence of back pain in adults18 and previous history of back pain as a predisposing factor for future symptoms7,9,19-21. It has also been reported that a large percentage of symptomatic adults had their first back pain symptoms during adolescence or before their thirties22. Healthy postural habits adopted during daily activities may protect the spine from overload and prevent postural deviations that may lead to pain. However, a lack of knowledge and adequate instruction during childhood may result in inadequate postural habits, which in turn may lead to structural deformations and pain in adulthood23.
Educational initiatives are essential for schoolchildren. Providing information to this population will help them to find local and individual solutions for ergonomic risks24. For the working population, educational programs combined with adjustable furniture showed improvements in workstation set-up25,26. In contrast, providing adjustable furniture does not mean postural improvement for adults if an instruction program is not provided and periodically reinforced27 and vice versa. Thus, both actions are important for back pain prevention. Unfortunately, school furniture design is a problem that goes unrecognized by educational managers, and health practitioners only have preventive programs and orientation as tools to deal with this problem during childhood.
As proposed by Prochaska and DiClemente's Stages of Change Model28, to change an unhealthy habit, knowledge should be acquired about the consequences of doing things in an undesirable way. Behavioral changes are an intentional process and comprehend different stages. The initial stages (pre-contemplation, contemplation, and preparation for action) include changes in the cognitive process. During these stages, it is important to encourage measures that increase the level of knowledge regarding the pros and cons related to behavioral change.
To our knowledge, ergonomic problems affecting schoolchildren are disregarded in the majority of schools. The national literature reports only two studies carried out in this environment29,30, one of them being specific to backpack risk29 and the other to sitting posture30 risk. International studies found good results for educational preventive programs conducted in Israel24, Belgium14,20,31,32, United States17, and Japan33.
Thus, this study aimed to describe the implementation of a multifactorial back care program and to evaluate the effects of this back care program on the level of knowledge of spine care among students from 4th to 8th grade from a public school in a city in the interior of the state of São Paulo, Brazil.
Subjects and settings
A physical therapist from the municipal health department initiated contact with the school that belonged to her coverage area of basic health care. After this contact, the staff of Universidade Federal de São Carlos (UFSCar), São Carlos, SP, Brazil, visited the school to propose the back care program, and the principal approved its implementation.
Four hundred and eighty subjects from 4th to 8th grade from a public school in the interior of São Paulo state, Brazil, were invited and voluntarily agreed to participate in the study. Three hundred and ninety two students completed the pre- and postintervention assessments (dropout rate of 18%). The students were aged 9 to 16, including 197 (50.3%) female and 195 (49.7%) male students. The distribution of students in shifts and grades is shown in Table 1.
This study followed National Health Council Resolution 196/96 on ethical issues and was approved by the Ethics Committee of UFSCar (approval number 039/2009).
A pilot test was initially carried out with students from 1st to 8th grades and teachers to make the questions suitable for the students' comprehension level. During this test, we found that the questionnaire was not suitable for 1st to 3rd grades, since the students did not understand its content. Thus, only 4th to8th grade students took part in the program. The questionnaire was adapted from national34,35 and international31 literature and, whenever possible, illustrations were included. Considering that eight out of ten questions were based on identification of correct postures in illustrations, we considered that an extensive validation and cross-cultural adaptation was not required for the use of this questionnaire. The questions are shown in Appendix 1.
The program comprised 6 phases: pre-intervention assessment, lesson 1, lesson 2, practical lesson (contest), post-intervention assessment, and two-year follow-up assessment. The questionnaires were applied in the classroom during regular school hours. Every student received a copy of the questionnaire, which was answered with the help of a physical therapist who read it out loud and answered any questions raised by the students. The time interval between the pre- and post-intervention assessments was 9 weeks, and between the post-intervention and follow-up assessments, it was 2 years (Figure 1). The back care program comprehended three meetings, two oral presentations, and one practical lesson of approximately 50 minutes each, conducted in three consecutive weeks. The first presentation was on spine anatomy and physiology including a model of a human skeleton, vertebrae, intervertebral discs, muscles, ligaments, nerves, as well as their location and function descriptions. Topics related to physiological curves of the spine and deviations, such as scoliosis, hyperkyphosis, and hyperlordosis, were also presented.
The second presentation was on the correct sitting posture during school and leisure activities and how to choose the correct furniture and the correct standing position (shoulder, hip, and feet alignments). The following topics were also discussed with the students: how to lift and transport objects correctly; risk postures for developing spinal deviations; and recommendations on how to use school backpacks, including the best way to carry them, the ideal size, the importance of using both shoulder straps, and the maximum recommended load.
In both presentations, visual aids to illustrate the topics and practical demonstrations were used. At the end of each presentation, the students answered oral questions related to what was taught to improve their learning achievements.
Following these presentations, there was a competition including 9 tasks so the students could apply the principles they had studied in a real situation. The lesson content was similar for children from 4th to 8th grade, however, the language and examples were adapted according to age through analogies to everyday situations. For children, we compared intervertebral discs to an onion, ligaments were associated with adhesive tape, and so on. For adolescents, we asked if they had back symptoms or postural deviations, how they carried heavy boxes, etc.
The data were tabulated as follows: questions correctly answered scored 1, unanswered questions scored 0, and those incorrectly answered scored -1. The one point deduction was given to incorrect answers to discourage students from guessing when they did not know the answer. The proportion of correct, incorrect, and no answers was calculated for each question in the pre- and post-intervention assessments.
Each student was given a total score by adding up the scores of the individual questions, and the average score of each grade was calculated. This procedure was conducted for the pre- and post-intervention assessments. The values obtained were compared to identify possible differences between the average scores before and after the intervention.
The statistical analysis included Levene's test for homoscedasticity and the Shapiro-Wilks test for normality. Since the data did not meet the parametric ANOVA criteria, pre-and post-intervention scores as well as follow-up results were compared using the Friedman test with Dunn's post hoc to identify which differences were significant. The Kruskal-Wallis test (non-parametric ANOVA) was applied to check existing differences among school grades with Dunn's post hoc to identify which differences were significant. The chi-square test was applied to verify the association between individual questions and grade. All analyses were carried out in the software SPSS (version 11.5), and the significance level was set at 5% (p<0.05).
Table 2 shows that the proportion of correct answers increased in the post-intervention assessment for all questions. At follow-up, the proportion of correct answers was slightly lower than post-intervention results for the majority of the questions, except for questions 1 and 2.
Questions 1 and 2 showed the highest increase between the pre-and post-intervention assessments (57% and 52%, respectively). However, these questions also showed the lowest proportion of correct answers and a high percentage of incorrect answers at follow-up. The highest proportion of no answers was observed for question 1. Question 2 showed the highest proportion of incorrect answers in all assessments. It is also worth mentioning that the number of incorrect answers decreased between the pre-and post-intervention assessments, except for question 1, which presented a 17% increase in wrong answers. Questions 5, 6, 9, and 10 showed the highest decrease in incorrect answers, and this reduction varied from 18 to 33%.
There was a significant difference between the pre-intervention (3.6±2.9), post-intervention (7.5±2.2), and follow-up (5.1±2.5) scores, confirmed by the Friedman test (P<0.001). Figure 2 shows the scores between grades in the pre-and post-intervention assessments and in the follow-up assessment. There was higher data dispersion in the pre-intervention assessment when compared to the post-intervention assessment. In the latter, students of all grades increased their scores, and the 8th grade in particular achieved a median of 10, i.e. half of the group obtained the maximum score. The Kruskal-Wallis test showed differences among the grades in the post-intervention assessment (p<0.001), and Dunn's multiple comparisons test identified differences between the 8th grade and the other grades (p<0.05 for all comparisons). For questions 1 and 2, the chi-square test showed an association (p<0.05) between correct answers and grade.
The results of the present study showed that students improved their questionnaire score, demonstrating the efficacy of oral presentations and practical lessons to improve their level of back care knowledge even after a long period, as the twoyear follow-up results indicated.
Differences between grades in the post-intervention assessment were identified, indicating that the score was higher among the 8th grade students. One possible explanation is that the proposed intervention was more appropriate for these students. It is likely that the more advanced stage of cognitive development of this group and their better ability to concentrate helped them to connect the topics presented to their daily activities, resulting in a better performance in the post-intervention assessment. Furthermore, events such as previous pain experience among these students and their family members, as well as concerns about aesthetic postural aspects may have contributed to the better content assimilation by the students of this grade.
Steele, Dawson and Hiller36 indicated that further studies should be conducted to control confounding factors, such as students' age. The comparison between grades showed the importance of this confounding factor, partially showed by the chi-square association between grade and correct answers for questions 1 and 2. Thus, it is important that health professionals who work in schools pay attention to this aspect to achieve better results with the development of back care programs.
Considering the individual analysis of each question, it can be observed that the questions related to spinal anatomy and pathology (Q1 and Q2) and the question related to the maximum backpack load (Q7) showed the lowest proportion of correct answers and highest proportion of no answers. A possible explanation for these results would be associated with the higher complexity of these topics. Question 1 demanded greater attention from the students to correctly understand how it should be answered. Question 2 was ambiguous because, depending on the considered plane (sagittal or frontal), students could come up with different answers. Question 7 implied a percentage calculation that may have contributed to the higher proportion of incorrect answers, as the students have difficulty with mathematics37.
Questions related to handling of school materials (5, 6, 8, 9, and 10) and to sitting posture (3 and 4) showed the highest decrease in incorrect answers and the highest rate of correct answers. These questions included subjects close to the students' reality and illustrations that enabled them to understand better.
The results of similar intervention studies14,35 show a lower tendency for correct answers for most of the questions directly compared to those of the present study. The greater differences between the studies were found for those questions related to handling of materials and spinal curves.
Although the proposed program increased the students' level of knowledge, it does not necessarily lead to a positive postural behavior change. The inadequate facilities at most Brazilian state schools hinder the success of interventions as the one presented here. The furniture is standard size and does not meet the needs of the students' anthropometric characteristics, which vary significantly according to age, gender, and stage of physical development38,39 and due to the high rate of miscegenation of the Brazilian population. Adapting school furniture for an extremely heterogeneous population is challenging.
The limitations of this study are the lack of postural behavior measurement and the absence of a control group. The latter is a methodological limitation always considered in quality assessments of the studies included in systematic reviews36. This study did not include a control group for ethical and methodological reasons. For ethical reasons, the program was applied to all students enrolled at the school, providing postural orientation to all of them. The inclusion of a control group would raise methodological questions. If the control group was selected at the same school, "contamination" between groups could occur as the students could talk each other regarding the back care program, leading to biased results. In contrast, a control group from another school would have to be similar in terms of geographical, social, economic, and cultural levels.
The follow-up assessment allowed us to discover that the knowledge acquired could be retained over time. These results indicate that this type of intervention has the potential to produce long-term effects on the students involved in the project. Initiatives such as these, which include the implementation of a back care program, are very well accepted by students and teachers and should be developed by physical therapists or other health practitioners to become part of the regular curriculum.
The back care program contributed to an increase in the level of knowledge of spinal anatomy and physiology, adequate postures and furniture, and handling of school materials and other loads. This improvement in the level of knowledge was maintained for 2 years and was higher among the 8th grade students. This program can be conducted at schools by health practitioners who aim to prevent back pain in adults.
This work was funded by grants from Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq Proc. N. 476524/08-3), Brasília, DF, Brazil.
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Tatiana de Oliveira Sato
Departamento de Fisioterapia, UFSCar
Rodovia Washington Luiz, km 235
São Carlos, SP, Brasil
Appendix 1. Back care questionnaire adapted for the present study.
|Score your back care knowledge |
Q1- Identify the spine deviations in the illustrations.
Q2- How many curves does the spine have?
Q3- Identify which is the best sitting posture for studying.
Q4- Which furniture is best suited for the child's size?
Q5- What is the best way to carry a backpack?
Q6- What is the correct way to organize school materials in your backpack?
Q7- What is the maximum load you can carry in your backpack?
Q8- Which is the correct way to lift an object from the floor?
Q9- Which is the correct way to take a heavy object and put it in another place?
Q10- What is the best way to carry a medium-sized box?