Prevalence of postural deviations and associated factors in children and adolescents: a cross-sectional study

Abstract

Introduction:
Postural deviations are frequent in childhood and may cause pain and functional impairment. Previously, only a few studies have examined the association between body posture and intrinsic and extrinsic factors.

Objective:
To assess the prevalence of postural changes in school children, and to determine, using multiple logistic regression analysis, whether factors such as age, gender, BMI, handedness and physical activity might explain these deviations.

Methods:
The posture of 288 students was assessed by observation. Subjects were aged between 6 and 15 years, 59.4% (n = 171) of which were female. The mean age was 10.6 (± 2.4) years. Mean body weight was 38.6 (± 12.7) kg and mean height was 1.5 (± 0.1) m. A digital scale, a tapeline, a plumb line and standardized forms were used to collect data. The data were analyzed descriptively using the chi-square test and logistic regression analysis (significance level of 5%).

Results:
We found the following deviations to be prevalent among schoolchildren: forward head posture, 53.5%, shoulder elevation, 74.3%, asymmetry of the iliac crests, 51.7%, valgus knees, 43.1%, thoracic hyperkyphosis, 30.2%, lumbar hyperlordosis, 37.2% and winged shoulder blades, 66.3%. The associated factors were age, gender, BMI and physical activity.

Discussion:
There was a high prevalence of postural deviations and the intrinsic and extrinsic factors partially explain the postural deviations. Conclusion: These findings contribute to the understanding of how and why these deviations develop, and to the implementation of preventive and rehabilitation programs, given that some of the associated factors are modifiable.

Full text

Fisioter Mov. 2016 Oct/Dec;29(4):777-85
ISSN 1980-5918
Fisioter. Mov., Curitiba, v. 29, n. 4, p. 777-785, Oct./Dec. 2016
Licenciado sob uma Licença Creative Commons
DOI: http://dx.doi.org/10.1590/1980-5918.029.004.AO14
[T]
Prevalence of postural deviations and associated factors
in children and adolescents: a cross-sectional study
[I]
Prevalência de variações posturais e fatores associados
em crianças e adolescentes: um estudo transversal
[A]
Mariana Vieira Batistão, Roberta de Fátima Carreira Moreira, Helenice Jane Cote Gil Coury,
Luis Ernesto Bueno Salasar, Tatiana de Oliveira Sato*
Universidade Federal de São Carlos, (UFSCar), São Carlos, SP, Brazil
[R]
Abstract
Introduction: Postural deviations are frequent in childhood and may cause pain and functional impairment.
Previously, only a few studies have examined the association between body posture and intrinsic and extrinsic
factors. Objective: To assess the prevalence of postural changes in school children, and to determine, using
multiple logistic regression analysis, whether factors such as age, gender, BMI, handedness and physical ac-
tivity might explain these deviations. Methods: The posture of 288 students was assessed by observation.
Subjects were aged between 6 and 15 years, 59.4% (n = 171) of which were female. The mean age was 10.6 (±
2.4) years. Mean body weight was 38.6 (± 12.7) kg and mean height was 1.5 (± 0.1) m. A digital scale, a tapeli-
ne, a plumb line and standardized forms were used to collect data. The data were analyzed descriptively using
the chi-square test and logistic regression analysis (signiicance level of 5%). Results: We found the following
deviations to be prevalent among schoolchildren: forward head posture, 53.5%, shoulder elevation, 74.3%,
asymmetry of the iliac crests, 51.7%, valgus knees, 43.1%, thoracic hyperkyphosis, 30.2%, lumbar hyperlor-
dosis, 37.2% and winged shoulder blades, 66.3%. The associated factors were age, gender, BMI and physical
activity. Discussion: There was a high prevalence of postural deviations and the intrinsic and extrinsic factors
partially explain the postural deviations. Conclusion: These indings contribute to the understanding of how
*MVB: Doctoral student, e-mail: marivbatistao@gmail.com
RFCM: PhD, e-mail: roberta.carreira@gmail.com
HJCGC: PhD, e-mail: helenice@ufscar.br
LEBS: PhD, e-mail: luis.salasar@gmail.com
TOS: PhD, e-mail: tatisato@gmail.com

Fisioter Mov. 2016 Oct/Dec;29(4):777-85
Batistão MV, Moreira RFC, Coury HJCG, Salasar LEB, Sato TO.
778
and why these deviations develop, and to the implementation of preventive and rehabilitation programs, given
that some of the associated factors are modiiable.
Keywords: Disease Prevention. Low Back Pain. Posture.
Resumo
Introdução: Variações posturais são frequentes na infância e podem causar dor e prejuízo funcional. Embora
a prevalência de variações posturais em crianças já tenha sido avaliada, poucos autores investigaram a asso-
ciação entre a postura e fatores intrínsecos e extrínsecos. Objetivo: Avaliar a prevalência de variações posturais
em crianças e adolescentes e identiϔicar fatores explicativos para estas variações, dentre eles: idade, gênero,
dominância manual, índice de massa corporal (IMC) e atividade ϔísica, por meio da análise de regressão logísti-
ca múltipla. Métodos: A postura de 288 estudantes foi avaliada de forma observacional. Os sujeitos tinham
idades entre 6 a 15 anos, sendo 171 (59,4%) do sexo feminino. A idade média foi de 10,6 (2,4) anos, massa
corporal de 38,6 (12,7) kg e altura de 1,5 (0,1) m. Utilizou-se balança digital, ϔita métrica, ϔio de prumo e for-
mulários padronizados. Os dados foram analisados descritivamente, com o teste de Qui-quadrado e regressão
logística (nível de signiϔicância - 5%). Resultados: A prevalência de anteriorização da cabeça foi de 53,5%;
elevação do ombro 74,3%; assimetria entre as cristas ilíacas 51,7%; joelhos valgos 43,1%; hipercifose torácica
30,2%; hiperlordose lombar 37,2% e 66,3% de escápulas aladas. Os fatores associados foram idade, sexo, IMC
e não realização de atividade ϔísica. Discussão: A prevalência de variações posturais foi alta. Os fatores escolhi-
dos explicam parcialmente as variações posturais. Conclusão: Esses achados contribuem para a compreensão
do desenvolvimento destas variações e para a proposição de programas preventivos e de reabilitação, conside-
rando que entre os fatores analisados, alguns são modiϔicáveis.
Palavras-chave: Prevenção de Doenças. Dor Lombar. Postura.
Introduction
Good posture is a state of equilibrium of body
segments, in a position of least effort and maximum
support (1, 2). In children, whole body posture is in-
luenced by physical development, which depends on
nutritional, congenital and environmental factors (1).
Many postural deviations originate in childhood
and adolescence (2). Some of them are common in
children of the same age group and are considered
to be a response of the body to the demands of grav-
ity (3, 4). They are usually corrected spontaneously
with the development of muscle strength (1, 5, 6).
However, if they persist, they will lead to joint over-
load, causing discomfort and functional impairment
(3).
According to several studies, common postural
deviations found in at least 50% of healthy children
include poor formation of the longitudinal arch of the
foot; knee hyperextension and valgus; medial rotation
of the hip; pelvic anteversion; pelvic tilt; abdominal
protrusion; lumbar hyperlordosis; winged shoulder
blades; protruding shoulders; thoracic hyperkypho-
sis; and shoulder elevation (1, 3, 5, 7, 8, 9, 10).
It is important to diagnose postural deviations in
children, because their skeletal system is still sus-
ceptible to changes and poor posture is more easily
corrected at this stage of development (11, 12). Thus,
postural assessment should become a common prac-
tice in schools, in order to early detect and treat pos-
tural deviations in students (4). Besides this, schools
have the potential to develop children´s knowledge
and skills and to help them learn how to live a healthy
life (13, 14).
Postural assessment is a complex procedure, be-
cause it takes into account many intrinsic and extrin-
sic factors that can inluence an individual´s posture,
such as the environment, his/her social, cultural and
emotional status, physical activity, obesity, physio-
logical developmental disorders, sexual maturation,
gender and heredity (15).
Although many authors have investigated the
prevalence of postural deviations in children, only
few studies have examined the association between
body posture and intrinsic and extrinsic factors.
Arruda (16) has studied the association between
postural deviations and obesity in children aged 8-10
years. Detsch e Candotti (4) have found an associa-
tion between age and postural deviations in girls.

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Prevalence of postural deviations and associated factors in children and adolescents
779
Detsch et al. (3) have studied the association between
the postural deviations and type of school (public or
private), parental education, age, body mass index
(BMI) and body postures adopted in everyday situ-
ations. Penha et al. (9) have studied the association
between age and postural deviations. However, the
aforementioned studies have only used association
tests. Multiple logistic regression analysis, which al-
lows the simultaneous assessment of multiple factors
and can help understand the inluence of these fac-
tors upon postural deviations, has not been reported.
Thus, the objectives of this study were to deter-
mine the prevalence of postural deviations in school-
children aged 6 - 15 years, and to identify, using mul-
tiple logistic regression analysis, whether factors such
as age, gender, BMI, hand dominance and physical
activity are associated with these deviations.
Methods
Subjects and study site
All 1st to 8th graders from a public school in São
Carlos, SP, Brazil, were invited to participate in the
study. The selection criteria were: 1. formal consent
from a parent or legal guardian; 2. being in good
health at the time of the investigation; and 3. no
detected or reported neuromuscular, rheumatic or
metabolic disorders.
Three hundred and four (41.3%) of a total of 739
students enrolled at the school returned a signed con-
sent form and were then assessed. Of these, 16 were
excluded because they did not complete the assessment
procedures. Thus, the inal sample consisted of 288 stu-
dents whose characteristics are depicted in Table 1.
Table 1 - Participants' Anthropometric Data (mean ±
standard deviation)
Gender Female
(n = 171)
Male
(n = 117)
Total
(N = 288)
Age (years) 10.6 ± 2.4 10.5 ± 2.6 10.6 ± 2.4
Body mass
(kg) 39.1 ± 12.3 38.0 ± 13.2 38.6 ± 12.7
Height (m) 1.5 ± 0.1 1.5 ± 0.2 1.5 ± 0.1
Body mass
index (kg/
m2)
18.2 ± 3.5 17.5 ± 3.0 17.9 ± 3.3
This study met the criteria established by Resolution
196/96 of the National Health Council and was ap-
proved by the Research Ethics Committee of the Federal
University of São Carlos (CAAE 0124.0.135.000-08,
opinion 039/2009).
Equipments
The following equipments were used in this study:
plumb line, rotating platform, tapeline (with an ac-
curacy of 5 mm) and digital scale (G Life®, maximum
180kg with an accuracy of ± 100 gram).
Procedures
The researchers completed a questionnaire with
personal information such as age, gender, handed-
ness and physical activity, based on the students'
self-reports. After the interview, the children were
asked to change into bathing suits, so that the weight
of their clothes was not added to their weight and
we could get a better visualization of their body seg-
ments. Students' weight and height measurements
were then collected. Body mass was measured us-
ing a digital anthropometric scale, while height was
measured to the nearest 5 mm with a tapeline.
For the postural assessment, the children were
asked to step onto a rotating platform in front of one
of the researchers. Their feet should be about hip-
width apart and pointing straight ahead. Students
were instructed to stand still in a relaxed posture,
looking forward. A researcher rotated the platform
in order to prevent changes in position due to move-
ment by the subjects. Figure 1 shows a subject stand-
ing on the platform.
Note: Source: authors.
Figure 1 - Student standing on the rotating platform and
beside a plumb line for postural assessment.

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Batistão MV, Moreira RFC, Coury HJCG, Salasar LEB, Sato TO.
780
hemi-parts must be exactly symmetrical and, hypo-
thetically offset one another. In the side view, the
plumb line projection represents the gravity line in
the frontal plane. The plumb line ends slightly in front
of the lateral malleolus and also passes through most
of the bodies of the cervical and lumbar vertebrae
and the shoulder joint and slightly posterior to the
frontal transverse axis of the hip joint. The presence
of postural deviations was determined according to
the positioning of the aforementioned structures in
relation to the plumb line.
Data Analysis
The data were analyzed descriptively by calculat-
ing the proportion of individuals who had postural
deviations according to age, gender, body mass index
(BMI), handedness and physical activity.
BMI data were categorized as underweight (U), eu-
trophic (E), overweight (O) and obese (Ob), according to
the BMI curves by age provided by the North American
Center for Disease Control and Prevention (20).
Students were divided into three age groups. The
choice of these age groups was based on the litera-
ture, so that the irst group (6 - 9 years) was the pre-
puberty age group; the second group (10 - 12) was
the female puberty age group and the third group
(13 - 15) was the male puberty age group (21, 22).
The statistical analysis was performed using
the Statistical Package for Social Sciences software
(SPSS). Multivariate analysis of variance was pre-
ceded by univariate analyses to identify signiicant
associations (P < 0.05) between the response variable
and the factors. Univariate analysis was performed
using the chi-square association test (χ2).
The response variables used in the logistic regres-
sion analysis were all the postural deviations listed
above and explanatory variables were age, gender,
BMI, handedness and physical activity. We used a
logistic regression model with logit link function for
each postural deviation (response variable). For the
selection of important variables, we used the step-
wise selection method. All tests were two-tailed with
the level of signiicance set at 5%.
The sample size calculation was based on data on
the prevalence of postural variations, considering a
signiicance level of 5% and power of 80%. The ob-
tained sample was big enough for all postural devia-
tions analyzed, except elevation of the shoulders, for
which the calculation indicated a sample size of 340
Postural Assessment
When assessing posture, direct (quantitative)
measurements are comparatively more accurate than
subjective (qualitative) measurements (17). Direct
measurement methods include radiography and
software-based measuments (such as the ones us-
ing the Postural Assessment Software [PAS/SAPO]).
However, these types of assessments are more com-
plex, more time consuming, and restricted to certain
body parts (PAS/SAPO) and expose the subject to
radiation (radiography) (18, 19).
Qualitative assessment is more widely used in
clinical settings and more feasible for assessments in
larger sample sizes because it is more affordable, less
complex and requires less preparation of the study
site (9). For these reasons, qualitative assessment
was the method of choice for this study.
Two physical therapists and two senior Physical
Therapy students conducted the postural assess-
ments. Thus, all evaluators had the required train-
ing to perform the tasks of the assessments. In addi-
tion, a speciic eight-hour training was held for the
evaluators, in order to ensure the standardization of
data collection. The training consisted of discussing
the assessment form, deining the postural devia-
tions that would be analyzed and carrying out joint
assessments. Divergences during the assessments
were solved by consensus. Intra-evaluator reliability
was previously tested in 10 subjects and the results
showed an 80% agreement among measures.
The assessment was conducted by observation,
and the data for each subject were recorded on stan-
dardized assessment forms. Posture assessment was
performed in the anterior, posterior and lateral (right
and left) views. We identiied the main postural de-
viations in each view. In anterior view, we assessed
elevation of the shoulders, elevation of the iliac crests
and valgus knees. In the side view, we assessed for-
ward head posture, thoracic hyperkyphosis and lum-
bar hyperlordosis. Finally, in the posterior view, we
assessed the presence of winged shoulder blades.
Postural assessments were conducted using theo-
retical guidelines from Kendall et al. (1). According to
these authors, in the posterior view, a plumb line can
represent the gravity line in the mid-sagittal plane.
Thus, it should ideally go between the legs from the
midpoint between the heels, in the midline of the
pelvis, over the spine and the center of the skull base.
Also according to these guidelines, the right and left

Fisioter Mov. 2016 Oct/Dec;29(4):777-85
Prevalence of postural deviations and associated factors in children and adolescents
781
subjects. As the literature states with reference to the
adequacy of the sample size that at least 25 individu-
als should be included for each predictor variable, the
required sample size for multiple logistic regression
analysis was met (23).
Results
Tables 2 and 3, respectively, show the prevalence of
postural deviations according to the factors analyzed and
the logistic regression results for signiicant associations.
Table 2 - Prevalence of postural deviations [n (%)] according to age, gender, body mass index and physical activity. Values
in bold indicate a significant association (in the chi-square test [2]) between the response variable (postural devia-
tion) and the factor
Forward
head
posture
Shoulder elevation Elevation of the iliac
crest Valgus
knees
Winged
shoulder
blades
Factors (n) RLRL
Age (years)
6 - 9 104 37 (35.6) 32 (30.8) 34 (32.7) 25 (24.0) 15 (14.4) 47 (45.2) 83 (79.8)
10 - 12 119 69 (58.0) 49 (41.2) 44 (37.0) 48 (40.3) 16 (13.4) 54 (45.4) 78 (65.5)
13 - 15 65 48 (73.8) 17 (26.2) 38 (58.5) 25 (38.5) 20 (30.8) 23 (35.4) 30 (46.2)
Gender
Female 171 94 (55.0) 36 (30.8) 47 (40.2) 39 (33.3) 22 (18.8) 79 (46.2) 102 (59.6)
Male 117 60 (51.3) 62 (36.3) 69 (40.4) 59 (34.5) 29 (17.0) 45 (38.5) 89 (76.1)
BMI
UW 27 18 (66.7) 11 (40.7) 9 (33.3) 11 (40.7) 7 (25.9) 9 (33.3) 24 (88.9)
Normal weight 217 120 (55.3) 73 (33.6) 89 (41.0) 78 (35.9) 41 (18.9) 86 (39.6) 153 (70.5)
Overweight 22 10 (45.5) 8 (36.4) 10 (45.5) 6 (27.3) 1 (4.5) 12 (54.5) 8 (36.4)
Obese 22 6 (27.3) 6 (27.3) 8 (36.4) 3 (13.6) 2 (9.1) 17 (77.3) 6 (27.3)
PA
Yes 103 61 (59.2) 27 (26.2) 46 (44.7) 42 (40.8) 16 (15.5) 31 (30.1) 75 (72.8)
No 185 93 (50.3) 71 (38.4) 70 (37.8) 56 (30.3) 35 (18.9) 93 (50.3) 116 (62.7)
Note: BMI: Body mass index; UW: underweight; PA: physical activity.
Table 3 - Multiple logistic regression results of postural deviations in relation to the factors associated with them in the
univariate analysis
Postural deviations
Factors Forward head
posture Shoulder elevation Elevation of the
iliac crest
OR 95% CI p OR 95% CI p OR 95% CI P
Age
10-12 0.18 0.09-0.34 0.000 1.74 1.16-2.59 0.007 0.23 0.12-0.44 0.000
13-15 0.47 0.25-0.87 0.016 3.58 2.32-5.52 0.000 0.44 0.24-0.81 0.009
Gender
Male - - - - - - - - -
BMI
Normal 7.14 2.64-9.31 0.000 - - - 6.14 2.32-6.26 0.000
Overweight 3.03 1.78-5.16 0.000 - - - 2.80 1.66-4.71 0.000
Obese 2.18 0.81-5.85 0.124 ---
1.08 0.39-2.98 0.882
PA
No-- -- - ----

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Batistão MV, Moreira RFC, Coury HJCG, Salasar LEB, Sato TO.
782
There was a high prevalence of postural deviations
in the sample studied. 53.5% of the 288 subjects had
forward head posture; 74.3% had shoulder elevation;
51.7% had iliac crest elevation; 43.1% had valgus knees;
30.2% had thoracic hyperkyphosis; 37.2% had lumbar
hyperlordosis; and 66.3% had winged shoulder blades.
The prevalence of thoracic hyperkyphosis and
lumbar hyperlordosis were not associated with any
of the analyzed factors. For this reason, they are not
shown in Table 2. The same is true for handedness,
which was not signiicantly associated with any of
the postural deviations recorded.
The prevalence of winged shoulder blades was
found to decrease with age
(OR = 1.6), while the prevalence of forward head
posture (OR = 0.5), shoulder elevation (OR = 3.6)
and iliac crests elevation (OR = 0.4) were found to
be higher in the age group 13 - 15 years.
With regard to gender, we found a signiicant as-
sociation only between gender and winged shoulder
blades (OR = 0.3). Male students had a higher preva-
lence of this postural deviation.
BMI was also associated with postural deviations. The
forward head posture, elevation of the iliac crests, valgus
knees and winged shoulder blades were associated with
lower BMI, while the prevalence of valgus knee was asso-
ciated with higher BMI. Physical activity was signiicantly
associated with lower prevalence of valgus knees.
Regression analysis showed that winged shoul-
der blades were associated with factors such as age,
gender and BMI, with R2= 0.34. The other postural
deviations were less prevalent in the sample, ranging
from 7-16%.
Discussion
This study aimed to assess the prevalence of postural
deviations in children and adolescents, and to identify,
using multiple logistic regression analysis, whether
factors such as age, gender, BMI, hand dominance and
physical activity are associated with these deviations.
The results indicated a high prevalence of postural de-
viations among schoolchildren, especially forward head
posture (53.5%), shoulder elevation (74.3%), iliac crest
elevation (51.7%), valgus knees (43.1%), thoracic hy-
perkyphosis (30.2%), lumbar hyperlordosis (37.2%),
and winged shoulder blades (66.3%).
Table 3 - Multiple logistic regression results of postural deviations in relation to the factors associated with them in the
univariate analysis
Hosmer and Lemeshow
2=3.196; p=0.535; R2=0.162
Hosmer and Lemeshow
2=31.154; p=0.000; R2=0.068
Hosmer and Lemeshow
2=2.694; p=0.747; R2=0.136
Postural deviations
Factors Valgus knees Winged shoulder
blades
Age OR 95% CI p OR p
10-12 - - - 3.51 0.000
13-15 - - - 1.56 0.152
Gender
Male - - - 0.33 0.000
BMI
Normal 0.27 0.11-0.66 0.004 7.10 0.004
Overweight 0.38 0.25-0.57 0.000 2.85 0.000
Obese 0.72 0.29-1.78 0.482 0.54 0.254
PA
No 2.37 1.49-3.77 0.000 - -
Hosmer and Lemeshow
2=3.196; p=0.535; R2=0.162
Hosmer and Lemeshow
2=31.154; p=0.000; R2=0.068
Note: BMI: Body mass index; PA: physical activity

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Prevalence of postural deviations and associated factors in children and adolescents
783
Postural deviations usually occur in children of the
same age group and most often do not require treat-
ment (24, 25). Such deviations come in response to
different balance requirements and different growth
rates of body segments (1, 5). When the body reaches
maturity, the balance of forces and the proportional
growth of body structures generally lead to regres-
sion of postural deviations (1).
In this study, we found an association among age,
BMI and forward head posture. The literature has
reported that younger children have greater degrees
of forward head posture (9). From a musculoskel-
etal standpoint, more mature children compensate
in other regions of the spine and hip, minimizing ab-
normalities in the alignment of the head in relation
to the trunk. However, in this study, the prevalence of
forward head posture was higher in the age group of
13 to 15 years. It can be assumed that this change has
been inluenced by environmental factors. A previous
study (26) has assessed the posture of elementary
schoolchildren during classes and its relation to the
inadequacy of the school furniture. The results have
shown that 38% of the tables and 50% of the seats
were too low for older students (8th graders). Thus,
these children had to maintain a head and trunk lex-
ion posture most of the time. Furthermore, the same
study has shown that at least 10% of the time the
lexion postures adopted were close to 30 degrees,
posing risks to the children's health. Since children
generally spend 30% of their awake time at school,
the development of postural deviations may be as-
sociated with positions adopted in the classroom.
Shoulder elevation was associated with increased
age. This indicates that this postural change arises
during the growth phase, possibly due to the differ-
ent growth rates of body segments. This asymmetry
can also be associated with differences in overload
between body sides, which is caused by external fac-
tors such as improper carrying of school supplies and
asymmetrical sitting posture (9, 27). However, this
postural change was not associated with handedness,
although it was expected that the handedness might
be associated with an elevation of the contralateral
shoulder (1).
This study found that a high BMI and lack of physi-
cal activity were associated with higher prevalence
of valgus knee, which is in line with the literature
(11, 25). Also, according to these authors, these two
factors may be interrelated. Most of the study par-
ticipants who regularly performed physical activity
did not have valgus knees. Since the most frequent
physical activity is soccer, it can be assumed that the
practice of this sport, which predominantly involves
striking the ball with the medial aspect of the foot,
might contribute to reduce of knee valgus loading.
Resende et al. (28) have assessed 128 14-17-year-old
boys who played and who did not played soccer. The
authors have found that those boys who played soccer
regularly had a prevalence of varus knees as high as
67.7% and a prevalence of valgus knees as high as
21.5%. School boys who did not play soccer regularly
had a prevalence of varus knees and valgus knees as
high as 30.1% and 52.4%, respectively.
On the other hand, physical activity might also
be associated with lower body mass, which, in turn,
is also associated with a lower prevalence of valgus
knees. Silva et al. (10) have compared 24 obese and
nonobese 9-17-year-old children and found a preva-
lence of knee deviations of 81.2% among obese chil-
dren and of 22.2% among nonobese children.
According to the literature, valgus knees physi-
ologically occur at age two years and reach peak in-
cidence at age three years. The emergence of these
deviations is associated with the search for a greater
support base and for a greater balance when a child
practices new movement strategies to improve his
walking ability. From six to eight years of age this
postural change tends to regress as a result of internal
tibial torsion, longitudinal growth of the femur and
disappearance of the inner tigh fat pad (5).
Obesity causes overload because of the overweight
on the lower limbs, and leads to increased pelvic ante-
version causing internal rotation of the hips. Especially
in childhood, these factors, associated with the accu-
mulation of fat in the inner thighs and the search for a
greater support base, cause the malleoli to move apart.
This, in turn, results in the opening of the medial com-
partment and increased pressure in the lateral knee
compartment. With time and development, uneven
growth occurs between the two compartments, lead-
ing to the emergence of a permanent valgus deformity
of the knee (5, 29). In this study, we found an associa-
tion between obesity and valgus knees, which indicates
the need for preventive measures.
The prevalence of thoracic hyperkyphosis was not
signiicantly associated with any of the assessed fac-
tors. Penha et al. (11) have found an increased preva-
lence of hyperkyphosis with increasing age. Thoracic
hyperkyphosis was found in 21% of girls aged 7 years,
27% of girls aged 8 years, 45% of girls aged 9 years and

Fisioter Mov. 2016 Oct/Dec;29(4):777-85
Batistão MV, Moreira RFC, Coury HJCG, Salasar LEB, Sato TO.
784
rehabilitation programs should take these aspects into
account, in order to avoid adult structural problems that
can be prevented in childhood and adolescence.
References
1.
Kendall FP, Mccreary EK, Provance PG. Músculos –
provas e funções. Barueri (Brazil): Manole; 2007.
2.
Levangie P, Norkin C. Joint structure and function:
a comprehensive analysis. Philadelphia: F. A. Davis
Company; 2005.
3. Detsch C, Luz MH, Candotti CT, Oliveira DS, Lazaron
F, Guimarães LK, et al. Prevalência de alterações
posturais em escolares do ensino médio em uma
cidade no Sul do Brasil. Rev Panam Salud Publica.
2007;21(4):231-8.
4. Detsch C, Candotti CT. A incidência de desvios post-
urais em meninas de 6 a 17 anos da cidade de Novo
Hamburgo. Rev. Mov. 2001;7(15):43-56.
5. Asher C. Variações da postura na criança. São Paulo:
Manole; 1977.
6. Lueder R, Rice V. Ergonomics for children: Designing
products and places for toddlers to teens. Londres:
Taylor & Francis; 2008.
7.
Juskeliene V, Magnus P, Bakketeig LS, Dailidiene N,
Jurkuvenas V. Prevalence and risk factors for asym-
metric posture in preschool children aged 6-7 years.
Int J Epidemiol. 1996; 25(5):1053-9.
8.
Penha PJ, João SMA, Casarotto RA, Amino CJ, Penteado
DC. Postural assessment of girls between 7 and 10
years of age. Clinics. 2005;60(1):9-16.
9. Penha PJ, Casarotto RA, Sacco ICN, Marques AP, João
SMA. Qualitative postural analysis among boys and
girls of seven to ten years of age. Braz J Phys Ther.
2008;12(5):386-91.
10.
Silva LR, Rodacki ALF, Brandalize M, Lopes MFA, Bento
CB, Leite N. Alterações posturais em crianças e adoles-
centes obesos e não-obesos. Rev Bras Cineantropom
Desempenho Hum. 2011;13(6):449-54 .
11. Penha PJ, Baldini M, João SMA. Spinal postural align-
ment variance according to sex and age in 7- and
8-year-old children. J Manipulative Physiol Ther.
2009;32(2):154-9.
42% of girls aged 10 years. Cil et al. (30) have found an
increase in the prevalence of thoracic hyperkyphosis
among children up to 10 years of age, a decrease in its
prevalence at ages 10 - 12 years, and a new increase at
ages 13-15 years. However, in this latest study, the tho-
racic curvature has been quantitatively assessed and
parameter of normality used has not been described,
which makes data comparison dificult. Several au-
thors have associated increased thoracic hyperkypho-
sis with the period of rapid growth in childhood and
adolescence (11, 30), specially for females, who tend
to hide their developing breasts by increasing kyphosis
and forward protrusion of the shoulders (11).
The prevalence of winged shoulder blades de-
creased with increasing age, possibly due to muscle
development, which leads to better attachment of
the scapula to the thorax (1, 24). Penha et al. (9) have
qualitatively assessed the posture of 191 seven- to
ten-year-old children and found that 100% of the
boys at age 7 years, 95% at age 8 years and 93.8%
at age 9 years had winged shoulder blades. As in this
study, the girls in the aforementioned study had lower
prevalence rates, namely 71.8% at age 7 years, 71%
at age 8 years and 66.7% at age 9 years. According
to Asher (5), girls reach their maximum muscle force
earlier than boys because in girls the sexual matura-
tion process begins earlier than in boys.
Although this study has shown signiicant associa-
tions, it has some important limitations such as its cross-
sectional design. It would be relevant to conduct a longi-
tudinal follow-up of these children to assess the progress
of these deviations throughout the children's develop-
ment. However, despite the study design, the fact that the
number of children per age group was relatively homo-
geneous allows us to assume that the age groups used
provide a relatively consistent notion of development.
Conclusion
The indings of this study contribute to a better un-
derstanding of this topic, because they allowed us to
identify the relationship between postural deviations
and factors such as age, gender, BMI, handedness and
physical activity, using logistic regression analysis. These
indings also contribute to the understanding of how
and why these deviations develop, and to the imple-
mentation of preventive and rehabilitation programs,
given that some of the analyzed factors, such as BMI and
physical activity, are modiiable. Future prevention and

Fisioter Mov. 2016 Oct/Dec;29(4):777-85
Prevalence of postural deviations and associated factors in children and adolescents
785
24. Mac-thiong JM, Berthounnaud E, Dimar JR, Betz RR,
Labelle H. Sagittal alignment of the spine and pelvis
during growth. Spine. 2004;29(15):1642-7.
25.
Lafond D, Descarreaux M, Normand MC, Harrison DE.
Postural development in school children: a cross-sec-
tional study. Chiropr Osteopat. 2007;15:1.
26.
Batistão MV, Sentanin AC, Moriguchi SC, Hansson GA,
Coury HJCG, Sato TO. Furniture dimensions and pos-
tural overload for schoolchildren’s head, upper back
and upper limbs. Work. 2012;41:4817-24.
27.
Trevelyan F, Legg S. Back pain in school children -
where to from here? Appl Ergon. 2006;37(1):45-54.
28.
Resende LFM, Santos M, Araújo TL, Matsudo
VKR. A prática do futebol acentua os graus de geno
varo? Rev Bras Med Esporte. 2011;17(5):329-33.
29.
Brandalize M, Leite N. Alterações ortopédicas
em crianças e adolescentes obesos. Fisioter Mov.
2010;23(2):283-8.
30. Cil A, Yazici M, Uzumcugil A, Kandemir U, Alanay A,
Alanay Y, et al. The Evolution of Sagittal Segmental
Alignment of the Spine During Childhood. Spine.
2004;30(1):93-100.
Received in 01/19/2015
Recebido em 19/01/2015
Approved in 12/03/2015
Aprovado em 03/12/2015
12. Zaina F, Atanasio S, Ferraro C, Fusco C, Negrini A, Ro-
mano M, et al. Review of rehabilitation and orthope-
dic conservative approach to sagittal plane diseases
during growth: hyperkyphosis, junctional kyphosis,
and Scheuermann disease. Eur J Phys Rehabil Med.
2009;45:595-603.
13. Johnson J, Deshpande C. Health education and physi-
cal education: disciplines preparing students as pro-
ductive, healthy citizens for the challenges of the 21st
centrury. J Sch Health. 2000;70(2):66-8.
14.
Noll M, Candotti CT, Vieira A. Escola postural: revisão
sistemática dos programas desenvolvidos para esco-
lares no Brasil. Rev Mov. 2012;18(4):265-91.
15.
Guimarães MMB, Sacco ICN, João SMA. Caracterização
postural da jovem praticante de ginástica olímpica.
Braz J Phys Ther. 2007;11(3):213-9.
16.
Arruda MF. Análise postural computadorizada de
alterações musculoesqueléticas decorrentes do so-
brepeso em escolares. Motriz. 2009;15(1):143-50.
17.
Juul-kristensen B, Fallentin N, Ekdahl C. Criteria
for classiication of posture in repetitive work by
observation methods: A review. Int J Ind Ergon.
1997;19:397-411.
18.
Batistão MV, Carnaz L, Barbosa LF, Motta GC, Sato TO.
Posture and musculoskeletal pain in eutrophic, over-
weighed, and obese students. A cross-sectional study.
Motriz. 2014;20(1):192-9.
19.
Teixeira FA, Carvalho GA. Coniabilidade e validade
das medidas da cifose torácica através do método
lexicurva. Braz J Phys Ther. 2007;11(3):199-204.
20.
Centers for Disease Control and Prevention (CDC).
About BMI for Children and Teens. 2011 [cited 2013
Sep 19]. Available from: http://tinyurl.com/yewbvqf.
21. Rodrigues S, Montebelo IL, Teodori RM. Distribuição
da força plantar e oscilação do centro de pressão em
relação ao peso e posicionamento do material escolar.
Braz J Phys Ther. 2008;12(1):43-8.
22.
Rogol A, Roemmich J, Clark P. Growth at puberty. J Ado-
lesc Health. 2002;31:192-202.
23.
Bagley S, White H, Golomb BA. Logistic regression
in the medical literature: Standards for use and re-
porting, with particular attention to one medical do-
main. J Clin Epidemiol. 2001;54:979-85.