European Journal of Pediatrics 2017 (Jun); 176 (6): 807–814 ~ FULL TEXT
Sandra Elkjær Stallknecht & Katrine Strandberg-Larsen & Lise Hestbæk & Anne-Marie Nybo Andersen
Department of Public Health, Section of Social Medicine,
University of Copenhagen,
Øster Farimagsgade 5, 1014, Copenhagen, Denmark.
This study aims to describe the patterns in low back, mid back, and neck pain complaints in young adolescents from the Danish National Birth Cohort (DNBC) and to investigate the co-occurrence of spinal pain and stress and general well-being, respectively. Cross-sectional data from the 11-year follow-up of DNBC were used. As part of a web-based survey, a total of 45,371 young adolescents between 10 and 14 years old completed the Young Spine Questionnaire, the Stress in Children Questionnaire, and a one-item question on general well-being. Associations between spinal pain and, respectively, stress and general well-being were estimated by means of multiple logistic regression models. Almost one fifth of boys and one quarter of girls reported spinal pain. Compared with adolescents who reported no stress, adolescents reporting medium and high values of stress had odds ratios (OR) of 2.19 (95% CI 2.08-2.30) and 4.73 (95% CI 4.28-5.23), respectively, of reporting spinal pain (adjusted for age, gender, and maternal education). Adolescents who reported poor general well-being had an OR of 2.50 (95% CI 2.31-2.72) for reporting spinal pain compared to adolescents with good general well-being.
CONCLUSION: Spinal pain in childhood and adolescence is strongly associated
with spinal pain and generalized pain in adulthood. [2, 7, 11]. Therefore, it is of great importance to seek to treat and prevent spinal pain in children both to prevent discomfort for the child but also to reduce the individual and social costs of spinal pain in adulthood. If spinal pain among children and adolescents involves psychosocial well-being, then treatment as well as preventive initiatives might include psychosocial approaches, e.g., psycho education and development of appropriate coping strategies.
KEYWORDS: Back pain; Lumbar pain; Neck pain; School children; Thoracic pain
What is Known:
What is New:
The prevalence of spinal pain increases rapidly during childhood and
adolescence, but different measurement instruments result in great
variation in the estimates of spinal pain in children and adolescents.
Some studies have shown that different psychosocial measures are
associated with spinal pain in children and adolescents.
Spinal pain, as measured by the newly developed and validated Young Spine Questionnaire, is a common complaint in young adolescents
aged 10–14 years.
Spinal pain in young adolescents co-occurs with stress and poor general
From the Full-Text Article:
Low back pain is a public health concern as it is the leading
cause of years lived with disability, while neck pain ranks
fourth , and spinal pain has enormous costs to both the
individual and society due to disability pensions and treatment
costs.  Spinal pain often presents early in life and the
prevalence increases rapidly during adolescence to reach adult
levels at the age of 18 years. [7, 14] A meta-analysis from
2013 found a point prevalence of low back pain of 12%
among adolescents aged 9–18 years, whereas the 12-month
prevalence was 34%.  However, the included studies
showed great variation in the estimates of the prevalence.
Estimates from the Nordic countries showed a weekly occurrence
of spinal pain around 20% , and a small Danish
study showed a lifetime prevalence of spinal pain of 86% in
a population of adolescents aged 11–13 years with neck pain
being the most prevalent.  However, little is known about
pattern of spinal pain among adolescents.
The extent to which the individual is able to cope with the
pain is of great prognostic importance. It is believed that the
individual’s experience of the pain, in addition to somatic
conditions, might depend on coping strategies and psychological
and psychosocial conditions. [7, 26] In studies of adult
populations, a clear relationship between psychosocial factors
and spinal pain has been demonstrated [10, 17, 22], suggesting
that psychosocial factors are important predictors of spinal
pain. In children and adolescents, there is sparse evidence on
the potential co-occurrence of psychosocial well-being and
spinal pain. However, some studies have examined how emotional
problems, measured with five questions from the
Strengths and Difficulties Questionnaire (SDQ), were associated
with spinal pain in school children aged 11–14 years. [21, 30] Furthermore, spinal pain has been associated with perceived
stress, depressive symptoms, and other social, psychological,
and emotional factors in adolescents.  In addition,
poor general well-being has previously been associated with
spinal pain, in the lower back, in school children of different
ages. [9, 27] The identified studies generally contain only
small study populations and use very diverse measures of
The aim of this study was to describe the patterns in low
back, mid back, and neck pain as reported by young adolescents,
using the newly developed Young Spine Questionnaire
in the 11-year follow-up of the Danish National Birth Cohort
(DNBC), and to investigate the association between spinal
pain and stress and general well-being, respectively.
Participants and methods
The Danish National Birth Cohort is a nationwide study of
children, enrolled via their mothers, and followed from intrauterine
life and onwards.  The 11-year follow-up commenced
in July 2010, by inviting the part of the cohort older
than 11 years to participate, and from then and until October
2014, the children were invited to participate on their 11-year
birthday. A total of 87,322 mother-child pairs were invited to
complete web-based questionnaires that focused on the child’s
lifestyles, social life, well-being, physical activity, diet, and
health. In the present study, we used data from the child-completed
questionnaire and our study is therefore by design
cross-sectional. The young adolescents could sign in and out
of the questionnaire, and thus, they were not forced to answer
the entire questionnaire at once and, if needed, the questions
could be read aloud by the computer.
The 11-year follow-up questionnaire included a sub-division
of the Young Spine Questionnaire (YSQ)  that describes
life time experience of pain in the low back, mid back, and
neck regions separately. The first question was
“How often have you had pain in the neck?” and response options were
“Often,” “Once in a while,” “Once or twice,” and “Never”. If
the young adolescent reported to have experienced neck pain,
they were asked to note the intensity of the worst pain ever in
the neck using the revised version of the Faces Pain Scale
(rFPS) , which is a scale based on six faces with expressions
illustrating progressively worse pain. The questions
were repeated for the mid back and low back regions. An
illustration with the three spinal regions clearly shaded and
labeled was shown alongside these questions (Figure S1). Finally, questions on limitations in sport participation (“Has
neck or back pain sometimes stopped you from doing
sports?”), absence from school (“Have you stayed home from
school because of neck or back pain?”), and treatment-seeking
behavior (“Have you been to a doctor, chiropractor or physiotherapist
because of neck or back pain?”) due to spinal pain
were included. The response options for these questions were
also “Often,” “Once in a while,” “Once or twice,” and
For the regression analyses, spinal pain was categorized in
a number of binary variables. Low back pain was defined as a
report of pain in the lower back “often” or “once in a while”
and a score on the rFPS of 3 or above. Pain in the mid back
and neck regions was defined similarly. Overall spinal pain
was defined if the child fulfilled the definition for either low
back pain, mid back pain, or neck pain.
In addition, two variables on limitations and treatmentseeking
behavior due to spinal pain were coded. Limitations
due to spinal pain were defined as reported limitations in sport
participation or reported absence from school “Often”, “Once
in a while”, or “Once or twice” and were conditioned on overall
spinal pain. Thus, limitations in sport participation and
absence from school were combined in one measure for limitations.
Treatment-seeking behavior due to spinal pain was
coded in a similar manner.
The psychosocial measures we used were stress level and
general well-being. Adolescents were asked to complete the
Stress in Children (SiC) Questionnaire  about physical,
psychological, and behavioral responses to stress load,
stressors, and perceived stress. The questionnaire contains
21 statements with four possible response options for each
statement: “Never”, “Sometimes”, “Often”, and “Very often”.
Advised by the author of the questionnaire , we constructed
a scale by summing the answers and dividing the total score
by the number of statements, giving an average score. The
eight statements that are encoded reversely were recoded before
the statements were added up. The average scale score
(SiC score) ranges from 1 to 4. Also, advised by the author of
the questionnaire, we used the predefined cutoff points to
categorize stress into “No stress” (SiC scores <2), “Medium
stress” (SiC score 2 to <2.5), and “High stress” (SiC score
Additionally, adolescents were asked how they feel about
their life at present on a scale of 11 points from “worst” (=0) to
“best” (=10) life. This measure is an adapted version of the
Cantril Ladder for use in adolescents.  We used a cutoff
point of 6, which has previously been used elsewhere , to
dichotomize into the following: “good general well-being”
(score of 6 or more) versus “poor general well-being”.
The analyses were adjusted for the following covariates: age
(10–11, 12, 13–14 years) and gender of the child, and the
highest completed or ongoing maternal educational level at
child age 7 (primary education, secondary education, tertiary
education, or higher) as registered in Statistics Denmark.
Restriction of sample
A total of 87,322 children were invited to the 11-year followup
questionnaire, of which 39,125 (44.8%) did not respond.
The analysis sample was restricted to adolescents who answered
all questions regarding spinal pain, stress, well-being,
gender, and age and with information on maternal educational
level. There were 2,762 (5.73%) who did not answer the YSQ
and an additional 64 (0.14%) with missing information on the
SiC Questionnaire, the general well-being variable, or any of
the covariates. Thus, the study population consisted of 45,371
young adolescents (Figure 1).
Chi-square and Student’s t test were used to examine gender
differences in the distribution of spinal pain and pain intensity,
We calculated the Spearman’s rho correlation coefficient
between the SiC scale and the scale for general well-being
and compared the distribution in a bubble plot to examine
the correlation of these two psychosocial measures.
Logistic regression models were used to estimate the crude
and adjusted associations, expressed as odds ratios (OR) with
95%confidence intervals (95% CI), between the psychosocial
measures and various measures for spinal pain. The analyses
were not stratified by gender, as testing for effect modification
did not show any significant (P < 0.05) interaction with gender
and the psychosocial measures in any of the models. The
presented estimates are from models where stress and general
well-being were included separately, but we also analyzed
data by including them simultaneously in the models. All
statistical analyses were carried out in SAS version 9.4.
Nearly one fifth of boys (17.9%) and one quarter of girls
(23.8%) reported spinal pain in one or more regions, and increasing
frequency of spinal pain was associated with rising
child age and lower maternal educational level (Table 1). The
most prevalent pain area for both girls and boys was the neck,
followed by the mid back and lastly the low back, and spinal
pain was more frequent in girls in all three regions (Table 2).
Furthermore, girls reported higher pain intensity than boys in
all spinal regions (Table 2). Among young adolescents with
spinal pain in one or more regions, one third reported limitations
in doing sports (girls, 35.1%; boys, 31.8%), every sixth
reported absences from school (girls, 17.8%; boys, 14.5%),
and one in four reportedly sought medical care (girls, 26.0%;
The SiC scale correlated moderately with the scale for general
well-being with a Spearman’s rho correlation coefficient
of 0.56 (P < 0.001). The correlation is illustrated in Figure 2. The
figure also illustrates that not all young adolescents classified
with poor general well-being were classified with medium or
high stress level or vice versa. Using the SiC scale cutoff point
of ≥2.5, 3.7% of included young adolescents were classified
with high stress level, of which more than half (2.0% points)
also had poor general well-being. There was 5.8% of the included
young adolescents who were classified with poor general
well-being and the majority of these adolescents (5.1%
points) had medium or high stress levels. No notable gender
differences were observed in the way the SiC scale correlated
with the scale for general well-being.
We observed a stepwise association between stress and
spinal pain in one or more regions, which was only slightly
weakened after adjustment for age, gender, and maternal education.
In the adjusted analyses, young adolescents who reported
medium and high values of stress had an OR of 2.19
(95% CI 2.08–2.30) and 4.73 (95% CI 4.28–5.23), respectively,
of reporting spinal pain compared to young adolescents
without stress (Table 3).Young adolescents who reported poor
general well-being had an OR of 2.50 (95% CI 2.31–2.72) for
reporting spinal pain compared to young adolescents with
good general well-being (Table 3). For both the stress level
and general well-being, the same pattern was seen for limitations
and treatment-seeking behavior due to spinal pain
(Table 4) and additionally the same pattern was seen for all
three separate spinal pain regions, with the associations being
strongest for the neck and mid back (Table S1 and Table S2).
Stratified analyses on gender showed similar associations
for spinal pain in relation to stress and general well-being
among boys and girls, respectively. Modeling stress and
general well-being simultaneously, weakened the associations,
and this was most pronounced for general well-being,
but both associations remained statistical significant.
Spinal pain was frequently reported by Danish young adolescents.
Around one fifth of boys and one quarter of girls reported
spinal pain in one or more regions, and the most prevalent
area where both girls and boys reported pain was the neck.
Among young adolescents with spinal pain, one third reported
limitations in doing sports, every sixth reported absences from
school, and one in four reportedly sought medical care. Both
stress and poor general well-being were associated with spinal
pain as well as with limitations and treatment-seeking behavior
due to spinal pain. The association between stress and
spinal pain displayed a stepwise increasing pattern.
A meta-analysis from 2013 found great variability in estimates
of how prevalent low back pain is among children and
adolescents.  The variability may be due to differences in
sample selection, age and gender distribution, definition of
low back pain, reporting method, and recall period. The occurrence
of spinal pain found in the present study is consistent
with previously detected weekly incidence of spinal pain
among 11–15-year-old Danish children.  To our knowledge,
there is only one study besides the present using the
newly developed instrument YSQ. This study showed a high
lifetime prevalence of spinal pain (86%) in Danish adolescents
aged 11–13 years, but if limiting the definition to spinal pain
BOften” or BOnce in a while,” as in the present study, the prevalences
were reduced to 36%, 24%, and 20% for neck pain,
mid back pain, and low back pain, respectively.  It is likely
that adding a criterion for pain intensity to the spinal pain
definitions would further reduce the prevalence rates to a level
similar to the present study. Also, Aartun et al. found neck
pain to be the most common spinal pain site and low back
pain the least frequent, which is distinct from adult populations
where pain in the lower back followed by the neck are
the most common regions with spinal pain.  A number of
studies showed, similarly to the present study, that girls are
more likely to report spinal pain compared to boys. [1, 30]
We could not identify any studies using the same instruments
to examine the association between spinal pain and
stress or general well-being as the present study. However,
the sparse evidence that exists on the relationship between
spinal pain and psychosocial factors is consistent with the
results of this study. [6, 9, 21, 27, 30]
This study has several strengths. It is one of the first studies
using the instrument YSQ to estimate the occurrence of spinal
pain in a large population of young adolescents. The YSQ has
been shown to be feasible, have content validity, and be well
understood in children aged 9 to 11 years.  Also, the instruments
used to measure stress and general well-being were
validated in young adolescents. [16, 25] It was only necessary
to exclude a few adolescents from the analyses due to missing
values and we had access to background factors for confounder
control. We decided to include relatively few potential confounders
to prevent over adjustment and avoid including variables
that were part of the SiC instrument. Finally, all questions
were pilot-tested, and the questions were found to be
easily understood among the target population.
However, this study does comprise some limitations.
Firstly, this cross-sectional study cannot determine whether
spinal pain is caused by stress and poor general well-being
or vice versa. The cause-effect relationship between spinal
pain and stress and general well-being, respectively, is likely
to be mutually dependent. Likewise, it is not possible to conclude
anything about the underlying mechanisms and there
might be different mechanisms between the two psychosocial
measures and the various measures for spinal pain, including
spinal regions, and limitations in sport participation, absence
from school, and treatment-seeking behavior due to spinal
Secondly, the participants of the 11-year follow-up are a
selected sample. Only 30% of eligible pregnant women were
enrolled in the DNBC cohort  and only 55% of the invited
young adolescents responded to the 11-year follow-up.
Pregnant woman who participated in the DNBC were generally
healthier and had higher socioeconomic status than woman
who did not participate  and this selection has continued
in the follow-ups.  The differential drop out pattern
could induce non-participation bias, as children of parents
with lower socioeconomic status and shorter length of education
have higher incidence of spinal pain. [12, 22] Thus, it is
anticipated that this study may underestimate the occurrence
of spinal pain among Danish young adolescents. Furthermore,
it is conceivable that adolescents with spinal pain, high levels
of stress, and poor general well-being to a greater extent did
not participate in the 11-year follow-up due to lack of energy
or interest. If this hypothetical scenario is correct, the effect
estimates will potentially be underestimated.
Thirdly, there might be a potential effect of parents’ possible
presence when the child answered the questionnaire at
home, since one in three of the adolescents sat with one of
their parents while completing the questionnaire. However, if
the potential influence by parents should have biased our findings,
the adolescents’ responses to both the YSQ as well as the
SiC and well-being questions should depend upon systematic
differences in completion of the questionnaire, which we find
This study indicates that spinal pain may involve, or at least
co-occur with, psychosocial well-being among young
adolescents. It is plausible that in some cases children’s complaints
about spinal pain may be an expression of frustration
with psychosocial failure to thrive which the child cannot
otherwise express. Psychosomatic symptoms are frequent
among children and adolescents  and can be manifested
in different ways, e.g., headache, abdominal pain, and musculoskeletal
pain, including spinal pain. On the other hand, the
pain itself might also lead to some degree of social or emotional
distress, resulting in poor scores on the stress and wellbeing
Spinal pain in childhood and adolescence is strongly associated
with spinal pain and generalized pain in adulthood. [2, 7,
11]. Therefore, it is of great importance to seek to treat and
prevent spinal pain in children both to prevent discomfort for
the child but also to reduce the individual and social costs of
spinal pain in adulthood. If spinal pain among children and
adolescents involves psychosocial well-being, then treatment
as well as preventive initiatives might include psychosocial
approaches, e.g., psycho education and development of appropriate
The Danish National Research Foundation
established the Danish Epidemiology Science Centre, where the Danish
National Birth Cohort was initiated. The cohort is furthermore a result of a
major grant from this foundation. Additional support for the DNBC is
obtained from the Pharmacy Foundation, the Egmont Foundation, the
March Dimes Birth Defects Foundation, the Augustinus Foundation,
and the Health Foundation. The DNBC 11-year follow-up was supported
by grants from the Danish Council for Independent Research (DFF) and
the Lundbeck Foundation.
Sandra Elkjær Stallknecht: Ms. Stallknecht
analyzed the data and wrote the first draft of the manuscript.
Katrine Strandberg-Larsen: Ms. Strandberg-Larsen made substantial
contributions to conception and design as well as analysis and interpretation
of data, and reviewed and revised the manuscript.
Lise Hestbæk: Ms. Hestbæk developed the Young Spine
Questionnaire, made substantial contributions to interpretation of results,
and reviewed and revised the manuscript.
Anne-Marie Nybo Andersen: Ms. Andersen made substantial contributions
to interpretation of results and reviewed and revised the
All authors conceptualized and designed this study. All authors approved
the final manuscript as submitted and agree to be accountable for
all aspects of the work.
This particular work was supported by the University of
Copenhagen, the Danish Council for Independent Research (DFF), and
the Lundbeck Foundation.
Conflict of interest
The authors declare that they have no conflict of
DNBC = Danish National Birth Cohort
OR = Odds ratio
rFPS = The revised version of the Faces Pain Scale
SD = Standard deviation
SDQ = Strengths and Difficulties Questionnaire
SiC = Stress in Children
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