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Journal of Behavioral and Brain Science, 2011, 1, 81-86
doi:10.4236/jbbs.2011.13011 Published Online August 2011 (http://www.SciRP.org/journal/jbbs)
Copyright © 2011 SciRes. JBBS
Chronic Head ac he a ft er Pediatric Brain Injury:
A Systematic Review
Devi E. Nampiaparampil1,2
1Interventional Pain Management Service, Department of Veterans Affairs, New York, USA
2Departments of Anesthesiology & Rehabilitation Medicine,
New York University School of Medicine, New York, USA
Received February 12, 2011; revised March 23, 2011; accepted April 27, 2011
Introduction: Chronic pain is an under-diagnosed consequence of traumatic brain injury (TBI) in subjects
aged ≤16. The objective of this study was to determine its prevalence. Methods: The Ovid/Medline database
was searched for articles published between 1951 and February 2008 using any combination of the terms
brain injury, pain, headache, blast injury, and combat. The PubMed, MD Consult, Cochrane Collaboration,
National Institutes of Health Clinical Trials Database, Meta-Register of Current Controlled Trials, and
CRISP databases were searched using the keyword brain injury. 1110 articles were identified for evaluation.
258 articles were reviewed and 26 met the inclusion criteria for calculating the prevalence of chronic pain
after TBI. Three cross-sectional studies met the inclusion criteria for calculating this prevalence in the popu-
lation aged ≤16. Results: Twenty-six studies (18 cross-sectional, 5 prospective, and 3 retrospective) includ-
ing 4468 patients with TBIs were identified. Fifteen studies assessed headache (HA) pain in 1932 patients.
Of these, 1081 complained of chronic HA, yielding a prevalence of 56.0% (95% CI, 53.9% - 58.2%). Three
studies furnished data on 262 patients with TBI and age ≤16. One-hundred-fifteen of these subjects experi-
enced chronic HA suggesting prevalence of 43.9% (95% CI, 37.9% - 49.9%) in this population. We found
evidence to suggest that there is an association between TBI and the development of chronic HA pain. Con-
clusions: Chronic pain from headache is a common complication of TBI and is common even among chil-
dren with apparently minor injuries to the brain. The evidence suggests that this condition is independent of
psychiatric disorders such as post-traumatic stress disorder and depression.
Keywords: Traumatic Brain Injury, Pediatrics, Pain, Headache
The Centers for Disease Control estimates that 1.4 mil-
lion individuals in the United States suffer from trau-
matic brain injuries (TBI) each year . The diagnosis
can be made in patients with a history significant for loss
of consciousness, altered consciousness after head injury,
or post-traumatic amnesia . These head injuries can
occur either when the head forcefully strikes an object,
when an object penetrates the skull, or when brain tissue
undergoes a sudden acceleration, deceleration, or both.
In children, TBI most commonly occurs as the result of
motor vehicle accidents, falls, and sports injuries .
Each year, TBI in all ages leads to an estimated
235,000 hospitalizations and 50,000 deaths, in addition to
direct and indirect costs of $56.3 billion . After analy-
sis of the Healthcare Cost and Utilization Project Kids’
Inpatient Database, Scheier et al. found that in the year
2000, TBI in patients ≤17 years of age accounted for
more than $1 billion in hospitalization charges, making
TBI one of the most costly hospital diagnoses for chil-
dren . The primary cause of death among Americans
<24 years of age is brain injury from unintentional [5-7]
injury. In the pediatric population, nonfatal brain injury
can affect key developmental processes such as learning,
emotional awareness, and social functioning . Current
expert opinion regarding brain injury suggests that pedi-
atric TBI has fewer long-term consequences because of
the larger measure of brain plasticity in children com-
pared to adults. However, in the context of TBI, there is
D. E. NAMPIAPARAMPIL
Copyright © 2011 SciRes. JBBS
increasing evidence that the developing brain may have
unique vulnerabilities . Experimentally, there appears to
be increased post-injury apoptotic cell death in the devel-
oping brains of neonatal vs. mature animals [10-13]. Cli-
nically, studies have shown an increased risk of post-
traumatic seizures in pediatric patients compared to adult
Prior studies have shown that chronic pain is a poten-
tial complication of TBI [17-43]. Prior studies have shown
that patients with TBI have a high prevalence of chronic
pain syndromes such as headache [17-31], shoulder pain
, heterotopic ossification , complex regional pain
syndrome , and peripheral nerve injuries . The
association of TBI with chronic pain was first described
in 1915 in troops returning from World War I with “shell
shock” . One study of veterans returning from Iraq
and Afghanistan experiencing post-concussive syndrome
found that post-traumatic stress disorder accounted for
all symptoms except for pain. This suggests that the me-
chanism for developing chronic pain is physiologically
tied to brain injury .
Given the morbidity associated with chronic pain and
the availability of effective treatment strategies, this sys-
tematic review was initiated to determine the prevalence
of chronic pain as an under-diagnosed consequence of
traumatic brain injury (TBI) in subjects aged ≤16.
Studies were identified that could provide information on
the prevalence of chronic pain among patients who had
sustained TBI. The Ovid/Medline database was searched
for articles published between 1951 and February 2008
using any combination of the terms brain injury, pain,
headache, blast injury, and combat. The PubMed and
MD Consult databases were searched in a similar fashion
for additional articles. The Cochrane Collaboration, Na-
tional Institutes of Health Clinical Trials Database, Meta-
Register of Current Controlled Trials, and CRISP data-
bases were searched using the keyword brain injury.
All selected articles were published in peer-reviewed
journals and contained original data on pain syndromes
present after TBI with respect to prevalence, pain category,
risk factors, pathogenesis, and clinical course. Manual
searches were performed of the reference lists of selected
articles and the authors of 2 selected studies were con-
tacted regarding potential additional references. The
search was not limited by language or publication status.
No randomized controlled studies were found in the
search (all patients were recruited into studies after the
brain injury had occurred). Case reports and review arti-
cles were cited only if no other data were available.
The initial search yielded 1067 articles and 43 others
were selected from the reference lists of retrieved articles.
Of these 1110 articles, 1084 were excluded because they
did not fulfill the primary inclusion criteria: the preva-
lence of chronic pain could not be calculated among their
TBI populations. The three experts contacted for this
study were not aware of any negative studies that had not
The data from the final 26 studies on chronic pain af-
ter TBI were pooled by adding the results across studies.
Since the studies were cross-sectional (18), prospective
observational (5), or retrospective (3), none were given
additional weighting. The data from the studies evaluat-
ing headache were pooled to determine the overall pre-
valence of headache among patients with TBI. The data
from the 23 studies assessing the adult population were
used in a separate analysis. The data from the 3 studies
assessing pain in subjects ≤16 were pooled to determine
the prevalence of chronic headache in the pediatric
population. Chronic headache in the pediatric population
was defined headache present at >1 year after the initial
P values were derived by significance testing of two
population proportions using a 2-proportion z test with
unequal variances. The results of each individual study
were compared with those of the studies combined. The
prevalence rates of pain were calculated with 95% con-
fidence intervals in each single study and in the pooled
data. Analyses were performed using SAS version 9.1
(SAS Institute Inc, Cary, NC); p < 0.05 was considered
Twenty-six studies [17-34,36-43] (18 cross-sectional, 5
prospective, and 3 retrospective) including 4468 patients
with TBIs were identified that reported on the prevalence
of chronic pain after TBI. Table 1 provides a summary
of the articles selected for review in the pediatric popula-
Fifteen studies assessed headache (HA) pain in 1932 pa-
tients [17-31]. Among these subjects, 1081 complained of
chronic HA, yielding a prevalence of 56.0% (95%CI,
53.7% - 58.2%). Although several studies investigated
pediatric TBI, only 3 studies isolated headache as an
outcome measure [17-19]. These studies furnished data
on 262 patients with TBI and age ≤16. These 3 studies’
criteria for judging chronicity was that the subjects con-
tinued to have headaches at the time that they were re-
cruited. This time period was at least 1 year after the
Necajauskaite et al. conducted a cross-sectional study
D. E. NAMPIAPARAMPIL
Copyright © 2011 SciRes. JBBS
Table 1. Headache prevalence in pediatric patients with traumatic brain injury.
Study Study Design
Patients Time after
Event Severity Pain Prevalence
Necagauskaite et al.,
2005  Cross-sectional 102 1 - 5 years Mild
62.7% (95% CI, 53.3% - 72.1%) with HA one year
after trauma; 42.2% had moderate HA; HA was present
≥8 days/month in 43.8% of subjects evaluated at 1 year
after trauma and in 12.5% at 2 years after trauma
et al., 1998  Cross-sectional 22 3 years Mild 45.4% (95% CI, 24.6% - 66.2%) had HA
Lanzi et al., 1985  Cross-sectional 138 12 - 18
29.7% (95% CI, 16.1% - 30.2%) with HA; 6.5%
diagnosed with migraines
in Lithuania investigating post-concussion syndrome in
children aged 4 - 16, who had experienced a single mild
TBI . 72.5% of the population was male and the
mean age at the time of evaluation was 11.3 for males
and 9.9 for females. These 102 children were evaluated 1
- 5 years post-TBI. 70.6% of the children had headache
immediately after the trauma. 62.7% experienced chronic
HA. 47.1% reported headache being present prior to the
trauma. Of the headache-free respondents, 51.9% devel-
oped post-traumatic headache. The authors found that in
children with mild TBI, there was a significant increase
in the number of headaches after the trauma (p < 0.03).
There may have been respondent bias in the study since
62.7% of parents responded that their children had head-
aches within the past year. Responses of children who
had sustained TBIs in the preceding 1 - 2 years were
compared to those of children who had had TBIs for 2 -
5 years. 45.3%, of patients with mild TBI reported head-
aches that occurred 1 - 7 days per month. 43.8% of pa-
tients with mild TBIs in the past year had ≥8 headaches/
month. This number decreased to 12.5% in subjects ≥2
years after trauma (p = 0.01). 42.2% of respondents had
headaches of moderate severity. 40.6% had unilateral
headaches of <30 minutes duration. 29.7% reported that
the headache was triggered by irregular sleep.
Overweg-Plandsoen et al. studied the pediatric mild
TBI population in the Netherlands . They selected
patients who met 1 of the following 3 criteria: 1) post-
traumatic LOC < 20 minutes, 2) post-traumatic amnesia
< 20 minutes, and 3) presence of at least 2 of the follow-
ing symptoms: headache, nausea and vomiting, and de-
cline of consciousness after a lucid interval. Of the 22
children who had sustained mild TBIs 2 years prior,
45.5% developed post-traumatic headache.
Lanzi et al. studied the incidence and clinical charac-
teristics of headache in the pediatric population 12 - 18
months after cranial trauma in Italy in 1985 . These
patients had all had injuries that necessitated hospitaliza-
tion. One-hundred-thirty-eight individuals aged 3 - 17
participated in the study. The children were questioned
by the examiners regarding headache symptoms in the
presence of at least one parent. 29.7% of them reported
chronic headache. In 6.5%, the headache was migrainous
in nature. The severity of the brain injury was differenti-
ated according to the following criteria: mild = no loss of
consciousness; moderate = loss of consciousness; severe
= loss of consciousness with residual focal neurologic
signs. The majority of respondents (63.8%) had mild
TBIs. The authors reported that there was no correlation
between site of head injury and site of headache in
41.5% of patients. This study suggested that headache
was relatively more common in patients with moderate-
severe trauma. Interestingly, the study also reported that
two of the pediatric patients with pre-existing diagnoses
of migraines had remission of symptoms after the trauma.
There is only one other study that was reviewed that
discussed resolution of pain symptoms after head trauma
These 3 studies [17-19] including 262 patients, pro-
vided data on the pediatric TBI population. 115 of these
children reported chronic headache pain, yielding an
estimated prevalence rate of 43.9% (95%CI, 37.9% -
49.9%). We found evidence to suggest that there is an
association between TBI and the development of chronic
This prevalence of chronic headache in this population
appears to be lower than the prevalence rate of 57.8%
found in a companion study of primarily adult patients
. This may be because pediatric and adolescent pa-
tients may have better outcome measures than adult pa-
tients. Alternatively, this difference could be due to
methodological limitations with respect to recruitment
bias and measurement bias.
In terms of recruitment, Necajauskaite et al. and Over-
weig-Plandsoen et al. selected subjects who had been seen
in the emergency rooms of academic hospitals [17,18].
Lanzi et al. selected patients who had previously been
hospitalized for their head injuries . In their study of
pediatric patients in Minnesota, Reid et al found a
post-admission case fatality rate of 4.6% . This was
higher than the 2.5% reported by Kraus et al. for a popu-
lation younger than 15 years of age . The authors
D. E. NAMPIAPARAMPIL
Copyright © 2011 SciRes. JBBS
posited that this might reflect the trend towards outpa-
tient management of mild brain injury. This suggests that
the patients seen by Lanzi et al. may have had more se-
vere brain injuries. Interestingly, their prevalence of pain
(29.7%) was lower than the prevalence found in either of
the two studies: Necajauskaite (62.7%) and Overweig-
Plandsoen (45.4%). This is in line with studies in adult
patients where the prevalence of chronic pain appears to
be higher in those with apparently minor head trauma.
It is possible that children with more cognitive diffi-
culties may have been unable to process or accurately
respond to questions about their headaches. Both the
Necajauskaite and Overweig-Plandsoen studies had in-
vestigators who questioned the parents about their chil-
dren’s symptoms [17,18]. In the Lanzi et al. study, the
children were questioned directly . This may also have
contributed to the difference in the apparent prevalence
of chronic headache.
A general limitation in measuring the incidence of
post-traumatic headache in pediatric patients is in deter-
mining whether the headache is the result of trauma or
whether it is a migraine or other headache syndrome that
would have manifested itself over time irrespective of
the head injury.
In addition, this review has specific limitations. First,
all of the studies evaluating pediatric pain are cross-sec-
tional so we do not know how symptoms may change
with time. Second, it is possible that the study popula-
tions demonstrated heterogeneity in terms of cause of
injury, treatment at the time of injury, recruitment pro-
cedures, and differences in and assessments of pain. The
patients were selected from three different countries:
Lithuania, the Netherlands, and Italy, where the epide-
miology and management of TBI may be different from
country to country. All of the studies utilized conven-
ience samples rather than random samples. Third, all of
the data relied on patient report, which can be biased.
Fourth, most of the studies did not provide information
necessary for further subgroup analyses. Future research
would benefit from standardization in this regard.
Traumatic brain injury is one of the main causes of
morbidity and mortality in the pediatric and adolescent
population. Chronic pain may be one of the main con-
tributors to the morbidity associated with this diagnosis.
This is the first systematic review to assess the preva-
lence of chronic headache pain in this population. The
findings suggest that more attention should be directed
towards evaluating children who have history of head
trauma for chronic headache.
Chronic pain is a common complication of TBI and con-
tributes to morbidity as well as potentially poor recovery
after TBI. Given the high prevalence of chronic headache
after pediatric TBI, it may be beneficial for healthcare
providers, patients, and their families to be aware of
symptoms that could possibly follow the injury. This
might allow for earlier treatment of pain and improved
quality of life. It is also unclear what the financial impact
of untreated chronic pain is in this population. Pediatric
and adolescent patients may benefit from early treatment
strategies to decrease the morbidity that untreated chro-
nic pain can impose on them, their immediate caregivers,
and on society. Further research is needed to characterize
the nature and extent of post-traumatic pain in the pedi-
6. Author Contributions
Dr. Nampiaparampil had full access to all of the data in
the study and takes responsibility for the integrity of the
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