Posttraumatic Headache in Children

Head injuries are common among children and adolescents, with an estimated incidence of 1 to 2 million per year.¹ Fortunately, the vast majority of traumatic brain injury (TBI) in youth—up to 97%—is mild in nature and only a small portion of these injuries lead to chronic symptoms.¹ Headache is the most common symptom experienced after a head injury in both the acute and chronic periods. It is critical for pediatricians and child neurologists alike to be able to evaluate posttraumatic headache (PTHA), identify risk factors for the development of PTHA, provide treatment options, and counsel families appropriately on expectations regarding the nature and duration of symptoms.

The International Classification of Headache Disorders (ICHD-3) defines PTHA as a headache beginning within 7 days of injury or resumption of consciousness after a traumatic head injury (Table 1).² The definition of mild TBI (mTBI), also termed concussion, is given in Table 2 and includes loss of consciousness for no more than 30 minutes; transient amnesia, confusion, disorientation, or impaired consciousness for no more than 24 hours; or 2 or more of the following: nausea, vomiting, visual disturbance, dizziness/vertigo, gait or postural imbalance, and impaired memory or concentration. In mTBI there are no signs of trauma on imaging (ie, no skull fracture, intracranial hemorrhage, or brain contusion).

Headache is the most common symptom reported by children and adolescents after head trauma. Typically, children are asymptomatic within a few weeks of injury. A study found that approximately 1 in 10 children seen in the emergency department for mild TBI experienced headaches 15 days after injury.³ Even smaller proportions of children, between 3.2% and 11%, go on to report symptoms 3 months after injury, at which point they meet criteria for chronic posttraumatic headache (cPTHA).^3-6 Higher rates of cPTHA (9.4%) have been reported in children admitted to the hospital for head injury.⁴ Rates of PTHA continue to decline as the time from injury increases.

Risk Factors

Several studies have attempted to characterize who will go on to develop more significant, chronic headaches after head trauma. Girls tend to experience cPTHA more often than boys.^7,8 Adolescents also tend to report PTHA after mTBI more frequently than young children and adults. Among children and adolescents with mild TBI, only 7% less than age 13 experienced headaches 3 months after injury, vs 17% of those ages 13 to 18.⁹ The predisposition of adolescents to concussion holds true among athletes as well. A 2015 meta-analysis of 6 studies involving high school and collegiate athletes showed high school athletes took 15 days to recover from concussive symptoms including headache, compared with 6 days for college athletes.¹⁰

Multiple studies have found that people with a history of headaches before injury are more likely to experience PTHA.^3,4 This has not held true in all studies, however; in a study of children and adolescents after sports-related concussion, those with preexisting migraines diagnoses had no higher risk of a prolonged recovery.¹¹ Family history is likely also relevant in determining the risk of cPTHA with a study of 52 children with cPTHA showing that 82% had a family history of migraine.³ Preinjury diagnosis of depression has also been associated with prolonged recovery times; 48% of those with premorbid depression reported postconcussive symptoms 3 months after injury compared with only 15% of those without depression.^8,9

Surprisingly, the severity and characteristics of the inciting head injury do not always help predict those who will go on to develop PTHA or other prolonged concussive symptoms. Paradoxically, rates of cPTHA have been shown to be higher in both adults and children with mTBI compared with moderate or severe TBI.^12,13 In a 2013 study, loss of consciousness, retrograde amnesia, and posttraumatic amnesia each conveyed increased risk for symptoms lasting more than 7 days.¹⁴ This was similar to the findings in a 2004 study in which both loss of consciousness and retrograde amnesia were associated with a prolonged time before return to play.¹⁵ In contrast, at 3 months post-injury, no evidence of loss of consciousness or amnesia as predictive factors in the development of cPTHA were seen.¹⁶ There is also conflicting data regarding the relevance of previous concussion in development of PTHA and other concussive symptoms.⁸

Mechanism

The wide variety of presentations of PTHA suggests that there may be multiple underlying mechanisms of headache after head injury. Acute headache is presumed to be a direct result of the associated head trauma. However, the mechanism underlying chronic posttraumatic headache symptoms is more ambiguous and has been speculated to involve significant biochemical shifts. More specific mechanisms are yet to be elucidated.

Overuse of analgesic medication is common among those with chronic symptoms after traumatic head injury and has been shown to be a likely influencing factor in headaches in several studies (See Medication-Overuse Headache in this issue). A 2014 study retrospectively analyzed headache course in 77 individuals with cPTHA and found that 70% of the cases met criteria for probable medication-overuse headache (MOH), with use of simple analgesics at least 15 days per month for 3 or more months.¹⁷

Clinical Characteristics

There are many phenotypes of PTHA, most of which resemble headaches in people who did not experience head trauma. Thus, it is important for providers to be familiar with the ICHD general headache criteria to be able to describe the symptoms of children and adolescents who have had head injury. Migraine-type headaches, as well as tension-type headaches, are seen commonly in the posttraumatic period. In a prospective Canadian study of 44 children with persistent PTHA after mTBI, 39% of children had migraine-type headaches, 9% had tension-type headaches, and 4% had probable MOH.³ Similar numbers were seen in an Israeli study of 74 pediatric patients with traumatic brain injury, in which 54% had headaches resembling migraines and 32% had symptoms most consistent with tension-type headaches.¹⁸

Association With Other Symptoms

Often, PTHAs are part of a constellation of symptoms that develop after head injury, referred to in the setting of mTBI as postconcussive syndrome (PCS), which can also be seen after more severe head injury. Headache is reported in 75% of people who continue to have PCS 6 months after injury and in all who report any ongoing symptoms 1 year after injury.^3,4 Commonly co-occurring symptoms in PCS include autonomic disturbances, including postural hypotension, light and sound hypersensitivity, and sleep disturbances. Many with PCS also complain of dizziness, nausea, vomiting, and blurred vision. Impaired cognition with difficulty focusing, impaired attention, and emotional symptoms such as irritability, anxiety, and sadness are also commonly recognized in this setting.

Clinical Evaluation

For acute trauma, the initial evaluation requires a thorough neurologic examination and careful inspection for signs of external head trauma. The Glasgow Coma Scale is frequently used to categorize the severity of TBI. Careful attention should be paid to assessment of balance, speech, and mental status. Fundoscopic exam is essential in identifying evidence of optic nerve edema or ocular hemorrhage. History taking should include detailed questions to understand any loss of consciousness or amnesia associated with the injury that will also help classify the severity of head injury. Head imaging is generally not indicated if the neurologic examination is normal but may be considered if there are concerning signs of external trauma or if there is loss of consciousness concerning for epidural hematoma.

Acute Management

Acute management of PTHA consists of analgesic use and supportive therapies. Nonsteroidal anti-inflammatory drugs (NSAIDs) are generally avoided in the first 24 hours after an injury because they may increase the risk of bleeding. They may be given, however, if the presence of structural brain injury or bleed is deemed highly unlikely by imaging or clinical evaluation. Similarly, if there is a possibility of surgical intervention being needed, NSAIDs should not be used. In a randomized controlled trial, 80 children and adolescents presenting to the emergency room with PTHA within 48 hours of mTBI who used a schedule that alternated ibuprofen and acetaminophen or ibuprofen alone had significantly fewer headaches during the week after injury compared with those who used only acetaminophen or no analgesics. Those who alternated acetaminophen/ibuprofen or used only ibuprofen also had a higher likelihood of returning to school.¹⁹ Several small studies have also investigated the use of intravenous (IV) analgesic therapies (also termed migraine cocktails) that have been largely effective for acute PTHA. A 2015 study found that among 254 people treated with various combinations of ketorolac, metoclopramide, and prochlorperazine within 14 days of head injury, 86% reported at least a 50% reduction in headache and 52% reported full resolution of pain.²⁰

Education regarding the expected duration and nature of symptoms after head trauma is a critical component of acute PTHA management. Individuals whose families received counseling related to expected symptoms and time course after mTBI reported fewer postconcussive symptoms 3 months after head injury compared with those who did not receive such education.²¹

Counseling regarding plans to return to school, return to sports, and return to normal activities is critical in patients with PTHA and TBIs in general. Strict bed rest is no longer a recommended approach after mild TBI. A gradual increase in cognitive load and physical activities has been proposed for athletes and can be adapted for nonathletes as well.

Chronic Management

There are no current guidelines or randomized controlled trials to aid providers in managing PTHA. The general recommendation is to categorize PTHAs based on their features and treat based on the features as if it was not trauma related. As with any headache, it is important to assess for any comorbid problems that could be contributing to headache, including sleep disturbance, mood or anxiety issues, balance or visual problems, or cognitive deficits. General headache hygiene is essential in people with trauma-related headache and includes maximizing sleep and hydration, optimizing stress management, limiting caffeine, and eating regularly scheduled meals. Analgesic use should also be discussed with families. Some experts have proposed limiting over-the-counter or prescription pain relievers to no more than twice per week to avoid the risk of MOH. A study found that among children with PTHA who met criteria for probable or definite, 68% had resolution or return to preinjury headache frequency after analgesics were discontinued.¹⁷

The use of preventive medications for headache has been explored in few pediatric PTHA studies, with evidence largely stemming from adult literature. A Canadian study examined response to prophylactic treatment in 44 children with PTHA who presented to a brain injury clinic. Participating children were assigned to therapies based on comorbidities such as sleep disturbance or obesity, with some taking multiple medications simultaneously. Tricyclic antidepressants (ie, amitriptyline and nortriptyline), flunarizine, topiramate, and melatonin were all used. The overall response was reassuring, with the majority of children (64%) having a positive response to treatment, including 44% with complete headache resolution.³ The effect of individual agents was not studied, however, limiting the applicability of this work. Another study found that 82% of adolescents with cPTHA had headache improvement with amitriptyline.²² Health care providers are encouraged to follow general headache management guidelines, with the use of tricyclic antidepressants, cyproheptadine, and anticonvulsants as they would in children without a history of trauma. Additional therapies such as beta blockers, riboflavin, and magnesium have also been used in posttraumatic headache, but lack any supporting research studies in this population.

New data will soon be emerging regarding the use of melatonin, which has been proposed to help headaches via its GABAergic activity, action on opiate receptors, and reduction in oxidative stress. In a small study 9 of 12 children who took melatonin for posttraumatic headache had a positive response.³ The PLAYGAME^a study recently concluded in Canada and is more formally studying the effects of melatonin in children with postconcussive symptoms via a double-blind, randomized placebo-controlled study.

Abortive therapies for PTHA include over-the-counter pain relievers and triptans, and there is emerging data supporting the use of occipital nerve blocks. As mentioned previously, many children and adolescents with cPTHA meet criteria for MOH, so analgesics should be used sparingly. Triptans have also been proposed for migrainous headaches in the posttraumatic period, although efficacy data is lacking in the pediatric population. In a small, yet promising study, peripheral nerve blocks of the scalp were administered to 28 children and adolescents with frequent PTHAs and 93% reported sustained relief lasting more than 24 hours after injections. Another 26% reported complete resolution of headaches after the procedure.²³ Similar findings were seen in a group of 14 children who received occipital nerve blocks, 9 of whom reported at least 50% reduction in headache frequency following intervention, with average headache days per month decreasing from 26 to 17 in the population.²⁴

Nonpharmacologic interventions have also been considered for the treatment of cPTHA. In a 2017 study, 74 children with daily PTHAs received at least 2 biofeedback sessions and 27 reported at least a 50% reduction in headache frequency after biofeedback.²⁵ In a randomized controlled study of 49 adolescents with general PCS (not headache-specific), children who received a combination of cognitive behavioral therapy, psychopharmacologic consultations and a collaborative care approach that included coordination with the child’s school and multidisciplinary meetings, were less likely to report high levels of postconcussive symptoms than who did not receive the intervention (13% vs 41%).²⁶ Physical therapy is another nonpharmacologic intervention that is promising for PTHA.

Communication between the medical provider, family, and school is encouraged in cases of prolonged symptoms after head injury. A 504 plan for school is often useful and facilitates the ability for children to rest during headaches and can clearly outline a child’s headache action plan.

Summary

Headache is the most common symptom in children and adolescents after traumatic head injury. Understanding of the underlying physiologic mechanism of PTHAs and the evidence base for management are limited. Key points to management of PTHA in the acute setting including a careful examination and investigation for signs of external trauma of intracranial hemorrhage. If neurologic and cranial examinations are normal, imaging is generally not indicated. Headaches should be managed according to existing guidelines for the treatment of nontrauma-related headaches, with nonopioid analgesics recommended for acute pain. Although most children and adolescents will fully recover from mTBI within a few weeks, a small subset will develop chronic symptoms. Preventive pharmacologic therapies can be used for those with frequent chronic headaches, in conjunction with behavioral and holistic interventions. Education for patients and families regarding common symptoms and their expected duration is critical and has been shown to improve outcomes.