Pediatric Chronic Pain Management

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Chronic pain is a significant yet underreported problem in the pediatric population, with a prevalence of up to 25%–45%. It has psychological, emotional, and social implications for both the child and the family. Common pain related functional issues include sleep problems, inability to pursue hobbies, eating difficulties, school absence, and inability to interact with friends. The potential for such consequences to negatively impact a child’s quality of life has fostered the development of a multi-disciplinary approach to treat pediatric pain. ^, A variety of behavioral, pharmacologic, and physical therapies are employed in pediatric chronic pain treatment regimens. Interventional procedures may be introduced after patients fail other treatment approaches. In this chapter, we discuss common chronic pain syndromes in children, along with their assessment, diagnosis, and management ( Box 43.1 ).

Box 43.1Chronic Pain in Children: Common Diagnoses

Neuropathic pain
- Complex regional pain syndrome type 1
- Peripheral nerve injuries
- Postamputation pain
- Deafferentation pain
Headache
Chest pain
Chronic illness
- Sickle cell crisis
- Cystic fibrosis
- Collagen vascular disease (e.g. juvenile rheumatoid arthritis, systemic lupus erythematosus)
Recurrent abdominal pain
Juvenile primary fibromyalgia
Pelvic pain
Back pain
Cancer-related pain

Assessment of Chronic Pain in Children

Assessment of children with chronic pain requires a biopsychosocial framework. Multidimensional models focus on various biologic, developmental, behavioral, affective, sociocultural, and situational factors that contribute to pain severity and the course to recovery. ^, Each domain may become a target of assessment and intervention. Several developmentally sensitive validated instruments are now available to measure various aspects of children’s pain ( Table 43.1 ).

TABLE 43.1

Methods for Assessment of Chronic Pain in Children and Adolescents

Pain Measure	Disability or Quality of Life	Stress and Coping	Anxiety	Depression	Other Behavioral Measures
Varni-Thompson Pediatric Pain Questionnaire (PPQ)Ages: 5–18	Functional Disability Inventory (FDI) Ages: 8–17 (plus parent form)	Children’s Hassles Scale (CHS) Ages: 8–17	Multidimensional Anxiety Scale for Children (MASC) Ages: 8–19	Children’s Depression Inventory (CDI) Ages: 7–17	Children’s Somatization Inventory (CSI)Ages: 8–18(plus parent form)
Children’s Comprehensive Pain Questionnaire (CCPQ) Ages: 5–19	Child Health Questionnaire (CHQ)Ages: 5+(plus parent form)	Pain Coping Questionnaire (PCQ) Ages: 8–18	Self-Report for Childhood Anxiety Related Disorders (SCARED)Ages: 9–18 (plus parent form)	Beck Depression Inventory-II Ages: 13+	Harter Scales of Perceived Competence for Children Ages: 4–12
Pain diary (written, electronic)Ages: 8+	Pediatric Quality of Life Inventory Generic Core Scales (PedsQL 4.0)Ages: 5–18 (plus parent report ages 2–18)	Pain Response Inventory (PRI)Ages: 8–19	Spence Children’s Anxiety Scale (SCAS) Ages: 8–12 (plus parent form)
Pain Behavior Observation Method Ages: 6–17	Pediatric Migraine Disability Assessment Scale (PedMIDAS)Ages: 6–18	Pain Catastrophizing Scale (PCS) Ages: 8-16	Revised Children’s Manifest Anxiety Scale (RCMAS) Ages: 6–19
Non-Communicating Children’s Pain Checklist (NCCPC-R)Ages: 2 years old to adult	Children’s Activity Limitations Scale (CALI) Ages: 8–16		State-Trait Anxiety Scale for Children (STAIC) Ages: 9–12
			Childhood Anxiety Sensitivity Index (CASI)Ages: 7–12

Two standardized interviews for school-age and adolescent children and their parents provided comprehensive yet practical evaluations of the child’s chronic pain: the Children’s Comprehensive Pain Questionnaire (CCPQ) and the Varni-Thompson Pediatric Pain Questionnaire. These interviews separately assess both the child’s and parents’ experiences of pain problems with open-ended questions, checklists, and quantitative pain rating scales. Some studies suggest potential limitations of these self-report measures because of cultural or cognitive differences among children. Additionally, the Pain Behavior Observation Method is a 10 minute observational pain behavior measure that can be used in children with chronic pain who may have difficulty with self-report measures because of age or cognitive limitations. Studies have supported the use of electronic versus paper pain diaries in children with chronic pain; electronic diary use was shown to be feasible and resulted in greater compliance and accuracy in diary recording than did traditional paper diaries in children with recurrent pain.

The well documented comorbidity between pediatric chronic pain and psychiatric disorders, particularly internalizing disorders such as depression and anxiety, obligates the clinician to screen for these disorders. The Children’s Depression Inventory (CDI) is a widely used self-report questionnaire for assessing depression in children aged seven to 17 years. It is important to assess anxiety symptoms because pain related disability is associated with anxiety sensitivity, a stable predisposition to fear of anxiety related sensations, and pain related avoidance behavior in children as well as adults with chronic pain. The Children’s Anxiety Sensitivity Index (CASI) is the only instrument developed to assess this characteristic in children.

Several well validated self-report questionnaires assessed anxiety in children (see Table 43.1 ). Two instruments, the Self-Report for Child Anxiety Related Disorders (SCARED) and the Spence Children’s Anxiety Scale (SCAS), include subscales that distinguish among specific anxiety disorders listed in the Diagnostic and Statistical Manual of Mental Disorders , Fourth Edition (DSM-IV). The Multidimensional Anxiety Scale for Children (MASC) and the Revised Children’s Manifest Anxiety Scale (RCMAS) include subscales that focus on other dimensions of anxiety. These subscales include physical symptoms, social and separation anxiety, and harm avoidance (the MASC) and physiologic symptoms, worry and oversensitivity, and concentration factors (the RCMAS), as well as social desirability items to detect inconsistency or randomness in reporting. The SCAS and SCARED provide both child and parent forms of the instrument, which allows examination of the convergence, or lack thereof, of the child’s and parents’ assessment of the child’s anxiety symptoms.

Factors that are closely linked with a child’s ability to function with chronic pain, such as perceived stress and coping, can assist in planning behavioral interventions. The pain coping questionnaire (PCQ), pain response inventory (PRI), and pain catastrophizing scale for children (PCS-C) assess pain specific coping strategies. The identification and modification of maladaptive coping responses constitute the core elements of cognitive behavioral approaches for treating pediatric chronic pain.

The ability to function in tasks of daily living is a critically important outcome measure to assess when treating children and adolescents with chronic pain. Frequently, pain cannot be completely relieved, and the child must learn to accept, cope, and adapt to the pain to enable participation in normal developmental activities and tasks, such as going to school, participating in extracurricular activities, and developing and sustaining social relationships. Several measures have been developed to assess a child’s functional abilities and quality of life. For example, the Pediatric Migraine Disability Scale (PedMIDAS) measures headache-related disability in children with chronic pain. This six-question tool assesses school, recreational, and social areas of participation and disability, domains relevant to all children with chronic pain. The Child Activity Limitations Interview (CALI) assesses the impact of recurrent pain on children’s daily activities as a way to identify appropriate targets for treatment. Additionally, the Functional Disability Inventory (FDI), developed to assess illness-related disability in children and adolescents, is a useful tool for evaluating the functional status of pediatric patients with chronic pain, a particularly important concern in children with pain disorders associated with psychological factors and pain associated disability syndrome. ²⁹ Pain related disability increases with age, and sex differences emerge in adolescence, with more girls than boys reporting pain related functional disability.

Quality of life can also be assessed in children and adolescents with chronic pain and as an index of treatment progress. One study found that the quality of life of children with recurrent headaches is similar to that of children with rheumatoid arthritis or cancer. The Child Health Questionnaire, including both children (CHQ-CF87) and parent reports (CHQ-50), and the PedsQL are measures that may be used to assess the general quality of life in children with chronic pain and have the advantage that the scores obtained on these instruments can be compared with standardized samples of scores obtained by children with other medical illnesses.

Other instruments that may further elucidate the psychological factors contributing to a child’s behavioral adaptation to chronic pain include the Children’s Somatization Inventory (CSI), which measures a child’s propensity to somatization, and the Harter Scales of Perceived Competence, which assesses a child’s judgment about his or her capabilities in important domains such as school performance, peer relationships, and athletic abilities. The child’s own judgment of his or her competencies in these domains is useful in understanding other factors that may contribute to the child’s functioning. For example, children with chronic pain who rate themselves as low on social and academic competency may have multiple reasons to avoid returning to school.

A thorough assessment of a child’s baseline status and progress is essential to guide interventions for chronic pain and evaluate the response to treatment. The core elements of assessment include a comprehensive evaluation of the child’s pain problem and screening for psychiatric comorbidity and functional status ( Box 43.2 ). More intensive screening of the child’s perceived stress and competencies and the parents’ and family’s functioning adds valuable information to treatment planning, especially in a child with long-standing pain problems who has not responded to previous treatment efforts.

Box 43.2Pediatric Questionnaire Components

1
Developmental level
2
Understanding of pain
3
Pain and medical treatment history
4
Interactions with others in relation to pain
5
Affect and behavior
6
Impact of pain on functional abilities
7
Family environment and stress
8
Coping skills
9
History of psychiatric illness
10
Medical problems

Psychological Pain Management Methods

A rehabilitative approach that emphasizes improving the child’s and family’s ability to cope with a chronic condition characterizes the course of most chronic pain treatment programs for children. The focus shifts from the narrow goal of pain reduction, which might be used in the treatment of acute pain, and broadens to decrease pain related emotional and behavioral disability, thereby increasing the child’s functional status. ^29, Research on the use of psychological therapies has focused mostly on clinical trials in children with headache. ^, In a meta-analysis conducted to evaluate the efficacy of behavioral interventions for pediatric chronic pain, Eccleston et al. concluded “There is strong evidence that psychological treatment, primarily relaxation and cognitive behavioral therapy, are highly effective in reducing the severity and frequency of chronic pain in children and adolescents.” Additionally, findings by Logan et al. suggest that interdisciplinary pediatric pain rehabilitation may facilitate increased willingness to self-manage pain, which is associated with improvements in function and psychological wellbeing. Finally, promising psychological treatments have also been used for children with disease-related chronic pain, including sickle cell disease, recurrent abdominal pain, complex regional pain syndrome (CRPS) type 1, musculoskeletal pain, and juvenile primary fibromyalgia syndrome, and further support the probable efficacy of psychological approaches to pediatric pain management.

These evidence-based psychological treatment programs are primarily rooted in cognitive behavior therapy (CBT) principles. Traditional CBT and more recent and emerging CBT variations, such as acceptance and commitment therapy, include a diverse array of standard intervention components that treat chronic pain by modifying children’s cognitive, affective, and sensory experiences of pain, their behavior in response to pain, and environmental and social factors that influence the pain experience. Education about chronic pain and problem solving for improving the child’s functional status is central to the child and family, assuming an active role in managing chronic pain. Cognitive techniques are targeted at modifying the child’s thoughts about the pain, in particular, to increase a sense of predictability and control over the pain, to alter memories about painful experiences, and to reduce negative cognitions about pain, notably catastrophizing. Decreasing somatic preoccupation, pain related rumination, and passive coping and learning to accept that the pain may persist are also key interventional goals in the psychological management of pain. Please see Table 43.2 for sample components of CBT in the treatment of pediatric chronic pain.

TABLE 43.2

Sample Components of Cognitive Behavioral Therapy for Pediatric Chronic Pain Treatment

Treatment Domain	Intervention Aims	Intervention Examples
Psychoeducation	Enhance health literacy Create positive treatment expectations and optimism for change	Engaging didactic instruction on basic neuroscience of pain Analogies describing how chronic pain operates as a faulty alarm and psychological treatments re-set pain signaling in the brain and body
Relaxation Practices	Activate parasympathetic nervous system Reduce emotional distress Enhance self-efficacy	Diaphragmatic breathing Progressive muscle relaxation Guided imagery
Cognitive Skills	Increase awareness of cognitive patterns Adopt adaptive thinking patterns Neutralize affective response to thoughts	Thought record and detective thinking for self-monitoring of thought-emotion-pain-action patterns Didactic instruction on cognitive distortions and thinking traps Cognitive reframing and positive reappraisal practices Cognitive defusion practices
Behavior Change Skills	Promote adaptive physical activity Increase daily developmentally adaptive daily activities Enhance healthy behaviors	Graduated exposure to experiences and environments associated with pain exacerbation and distress Structured physical activity pacing and behavioral activation strategies Graduated improvements to diet and eating behaviors Graduated implementation of behavioral sleep medicine principles to decrease nighttime cognitive arousal
Family-focused Skills	Enhance general family functioning Promote adaptive parent responses to pain Improve family communication patterns	Operant strategies for rewarding adaptive behavior changes Promote parent and family modeling of adaptive coping with pain and distress Communication strategies Structured problem solving skills training

Techniques to alter the sensory aspects of chronic pain include relaxation training, biofeedback, imagery, and hypnosis. Interventions aimed at modifying situational factors that exacerbate chronic pain and disability include contingency or behavioral management methods, modification of activity and rest cycles to achieve a steady pace of activity, and a gradual, structured plan for exposing patients and families to situations previously avoided because of pain. ^, Few analyses have been conducted to determine which components of psychological therapies may be essential in the management of pediatric chronic pain, but it is likely that for most chronic pain conditions, a combination of modalities will provide the best opportunity to affect the desired change. Changes in the emphasis of various behavioral components may present an opportunity to individualize treatment for a specific child by taking into account developmental, psychological, parental, and family factors, which may provide a way to tailor specific treatment to a child.

There is growing acknowledgment of parents’ crucial role in the successful rehabilitation of children with chronic pain, and thus they are increasingly becoming included as active partners in their child’s treatment. Parental interactions with their child related to pain and the family characteristics of children with chronic pain that may be associated with the development of maladaptive coping with pain are areas of active research. ^, Particular types of parental behaviors have been shown to influence a child’s ability to cope with pain. Walker et al. found that girls with functional abdominal pain are more vulnerable than boys to the symptom-reinforcing effects of parental attention. Interestingly, although the children with pain rated parental distraction as a helpful strategy, their parents rated distraction as having greater potential for a negative impact on their child than attention. Such findings help guide behavioral interventions for children with chronic pain and their families because parents’ beliefs in the most effective pain management strategies need to be targeted in any intervention designed to increase the functional abilities of children with chronic pain.

Several methods for the delivery of psychological interventions for recurrent or chronic pain in children have been shown to be effective, including those that involve intensive inpatient or outpatient treatment; those that are self-administered, school-based, Internet-based, ^, CD ROM-based ; and those that involve minimal clinic contact with home-based practice. The variety of methods for the delivery of these interventions offers opportunities to reach a broad population of children with chronic pain, thus increasing the potential to reach many more children than can be treated in specialized pediatric pain treatment centers. Optimally, the child’s school and other caretakers are included in the treatment team to ensure a consistent and comprehensive approach to the child’s pain and disability.

The complex nature of chronic pain in children creates many challenges with regard to its assessment and treatment, but this complexity can be exploited to provide the most efficacious methods for pain control and functional rehabilitation. Multidimensional assessment provides the foundation for optimal pain management and functional rehabilitation of chronic pain in children. Psychological interventions include a diverse array of techniques that treat chronic pain by modifying children’s cognitive, affective, and sensory experiences of pain, their behavior in response to pain, and environmental and interactional factors that influence the pain experience. Medical treatment of a child’s chronic pain may result in poorer outcomes without addressing the psychobehavioral factors that may contribute to pain and pain related disability. Research informed by multidimensional models of pediatric chronic pain can guide investigators in efforts to identify effective pain treatments, as well as the children for whom they work best.

Integrative Medicine Techniques

It has been reported that nearly 75% of pediatric patients, particularly those with chronic health disorders, have used some form of complementary and alternative medicine. A few of the tenets of integrative medicine (IM) include an emphasis on preventative health and lifestyle as well as a consideration of all dimensions of health, including body, mind, and spirit. These concepts make this field a promising adjunct for the treatment of pediatric chronic pain. Data regarding the implementation of IM in pediatric pain practice are limited to headache management and irritable bowel syndrome/functional abdominal pain syndrome. Despite this, a recent study found that it was common for pediatric pain clinics to provide IM, including acupuncture, mind-body therapies, massage, aromatherapy, nutrition counseling, and/or art/music therapy. We frequently recommend these therapies to our patients, as well as other techniques such as vitamin supplements/herbal remedies, chiropractic manipulation, and biofeedback.

Chronic Pain Syndromes

We will briefly discuss the diagnosis and management of some common chronic pain syndromes diagnosed in pediatric patients referred to chronic pain clinics. The introduction of multi-disciplinary pediatric pain clinics has allowed children to be seen in a single office visit by several consultants who can provide services for the child and develop a comprehensive pain management plan. An example of this model includes an anesthesiologist specializing in pain management, a pediatric pain psychologist, a physical therapist, a complementary medicine practitioner (including massage therapy and acupuncture therapy), and a specialist in biofeedback. This comprehensive approach reduces the need for multiple visits and exposes patients to a multimodal therapeutic approach.

Common pain syndromes in children include CRPS type I, headache, abdominal pain, juvenile primary fibromyalgia, chest wall pain, back pain, pelvic pain, and cancer-related pain. We address each of these conditions with a specific emphasis on accepted current therapy.

Complex Regional Pain Syndrome

CRPS type I or reflex sympathetic dystrophy (RSD), as originally named, is a complex syndrome consisting of neuropathic pain symptoms including allodynia and hyperalgesia, sudomotor dysfunction, and motor/trophic changes. In the pediatric population, it occurs more commonly in the lower extremity, with a female preponderance. Significant trauma is found with less frequency than in the adult population. Though there is a case report involving a two and half-year-old girl, it is generally seen in children older than nine years and more frequently in adolescents 11–13 years of age. Compared to adults, children are thought to better respond to non-invasive and treatment strategies and have a more favorable prognosis with treatment. However, early recognition and management are the major factors in improving outcomes and preventing resistant CRPS. Data regarding the epidemiology of CRPS type I is limited, though case reports exist describing pain in the sciatic distribution patients as young as three years old. ^,

Evaluation of Complex Regional Pain Syndrome I

History

A detailed history of the nature of the injury, the type and duration of the pain, relieving and aggravating factors, and dependence on medications is mandatory before evaluation.

Physical Evaluation

Thorough and systematic neurologic examination should be performed. Complete evaluation of the motor, sensory, cerebellar, cranial nerve, reflex, cognitive, and emotional functioning should be conducted. A concerted effort must be made to rule out a rare but possible malignancy or central degenerative disorder that may include laboratory evaluation, imaging such as X-rays, magnetic resonance imaging (MRI), or computed tomography (CT), or electromyography of the affected limb.

The strength of the extremities should be evaluated on several occasions. It is important to compare it with the strength in the contralateral extremity because CRPS I can occur in both extremities at the same time. Allodynia, pain to a stimulus that is not typically painful, is a common finding. Hyperalgesia, an increased painful response, is also common, particularly to cold sensation. Similarly, in adults, distribution is not generally restricted to particular dermatomes and commonly occurs along a glove-and-stocking distribution. Although nerve conduction studies may provide insight into a specific nerve injury, sensory abnormalities appear in different combinations in patients despite similar clinical presentations pointing to a central origin of pathogenesis. Quantitative sensory testing (QST) with thermal and vibration sensations and thermal pain detection thresholds in the affected limbs can be compared with data from normal healthy children. Although this involves cumbersome equipment, bedside QST may play a greater role in the diagnosis of CRPS I in children and adolescents. Bone scans may be helpful in the diagnosis of CRPS. However, there is limited data on their diagnostic accuracy in children. A decrease in isotope uptake was observed with suspected CRPS I.

Diagnosis

The diagnosis of CRPS I in children was based on symptoms and signs ( Table 43.3 ). The characteristics of pain and sensory, motor, and sudomotor changes may vary among patients. The 1994 International Association for the Study of Pain (IASP) criteria for CRPS I and the 2003 Budapest criteria can be applied to children and adolescents (see Box 43.3a and 43.3b ). However, it should be noted that although the Budapest criteria have been found to have nearly 100% sensitivity and 70%–80% specificity in the adult population, these criteria have not been validated in the pediatric population.

TABLE 43.3

Symptoms and Changes in Stages of Chronic Regional Pain Syndrome Type 1

Characteristic	Acute	Dystrophic	Atrophic
Pain	Hyperpathic, burning	Chronic
Blood flow	Increased	Decreased	No change
Temperature	Increased	Decreased	No change
Hair and nail growth	Increased	Decreased	Chronic change
Sweating	Decreased	Increased	No change
Edema	None	Brawny edema	Wasted muscles, atrophic skin
Color	Red	Cyanotic	Atrophic

Box 43.3aInternational Association for the Study of Pain Diagnostic Criteria for Complex Regional Pain Syndrome

Adapted from Bruehl S, Harden RN, Galer BS, et al. External validation of the IASP diagnostic criteria for complex regional pain syndrome and proposed research diagnostic criteria International Association for the Study of Pain. Pain . 1999;81:147–154.

1
Presence of an initiating noxious event or cause of immobilization
2
Continuous pain, allodynia, or hyperalgesia in which the pain is disproportionate to any known inciting event
3
Evidence at some time of edema, changes in blood flow, or abnormal sudomotor activity in the region of pain
4
Diagnosis excluded by the existence of other conditions that would otherwise account for the degree of pain and dysfunction

Box 43.3bBudapest Criteria

Budapest Criteria for Complex Regional Pain Syndrome
1.Continuing pain, which is disproportionate to any inciting event
2.Must report at least one symptom in three of four of the following categories
Sensory	Reports of hyperesthesia and/or allodynia
Vasomotor	Reports of temperature asymmetry and/or skin color changes and/or skin color asymmetry
Sudomotor/edema	Reports of edema and/or sweating changes and/or sweating asymmetry
Motor/trophic	Reports of decreased range of motion and/or motor dysfunction (weakness, tremor, dystonia) and/or trophic changes (hair, nail, skin)
3.Must display at least one sign at time of evaluation in two or more of the following categories
Sensory	Evidence of hyperalgesia (to pinprick) and/or allodynia (to light touch and/or deep somatic pressure and/or joint movement)
Vasomotor	Vasomotor: evidence of temperature asymmetry (>0.6°C) and/or skin color changes and/or asymmetry
Sudomotor/edema	Sudomotor/edema: evidence of edema and/or sweating changes and/or sweating asymmetry
Motor/trophic	Evidence of a decreased range of motion and/or motor dysfunction (weakness, tremor, dystonia) and/or trophic changes (hair, nail, skin)
4.There is no other diagnosis that better explains the signs and symptoms

Reproduced with permission: Harden RN, Bruehl S, Perez RSGM, et al. Validation of proposed diagnostic criteria (the "Budapest criteria") for complex regional pain syndrome. Pain . 2010;150(2):268-74.

Treatment of CRPS I

Treatment of CRPS should be immediate and directed toward restoration of extremity function and rehabilitation. Management of CRPS ( Box 43.4 ) can be frustrating for the caregiver and the patient as no single therapy can uniformly provide relief to these patients. The treatment plan should be multidisciplinary in nature. Although medications can be prescribed and procedure-based treatments may be performed in children, rehabilitative treatments show the best evidence for positive outcomes. Logan et al. studied the effects of an intensive, multi-disciplinary model of daily cognitive behavioral and physical occupation therapies with medical and nursing services for pediatric CRPS over a three week timespan and found that patients experienced significantly decreased pain perception, improved functional ability and limb function, and improved emotional functioning.

Box 43.4Management of Neuropathic Pain

CRPS , Complex regional pain syndrome; NSAIDs , nonsteroidal anti-inflammatory drugs; TENS , transcutaneous electrical nerve stimulation.

1
Nonpharmacologic Treatment

Hypnosis, biofeedback, visual guided imagery

TENS, physical therapy, occupational therapy

Individual and family therapy (day program if required)

2
Pharmacologic Therapy

Acetaminophen, NSAIDs

Tricyclic anti-depressants (e.g. amitriptyline, nortriptyline, doxepin); start at low doses, 0.1 mg/kg, and advance slowly

Anti-convulsants (gabapentin, pregabalin, carbamazepine, phenytoin, and clonazepam), systemic local anesthetics (mexiletine, lidocaine)

Serotonin and norepinephrine reuptake inhibitors

Opioids (morphine, methadone administered orally, intravenously, or via a regional technique [epidural or intrathecal], especially in cancer patients)

3
Regional Blockades for Chronic Pain

Epidural, subarachnoid and sympathetic plexus, peripheral catheter blockade

Sympathetic blockade for CRPS 1

Continuous catheter techniques may be used for five to seven days

Epidural and subarachnoid block for cancer patients: left in place for longer periods by subcutaneous tunneling

Neurolytic blockade for cancer

One of the primary goals is to return the child to a functional state and school, as a definitive resolution of the pain is not always possible. Most management techniques have been extrapolated from work done in adult patients. It is imperative to build trust with the patient and the parents. Family dynamics are important because the added burden of familial disharmony or parental abuse can worsen the symptoms. There seems to be a greater propensity for enmeshment in these families.

Psychological and Behavioral Therapy

Psychologic therapies are a pillar in the treatment of pediatric CRPS and may require the expertise of a pain psychologist. Although no one therapy has been proven to be the “gold standard,” CBT is generally the accepted treatment strategy. Other techniques, including biofeedback, visual guided imagery, and structured counseling, have been shown to assist in the development of adequate coping skills. Participation in a day program for acute psychological intervention has been valuable for some of our patients, specifically those with significant psychiatric co-illness. More detailed explanations of the various psychological interventions have been provided in a previous section.

Physical Therapy

Physical therapy is geared toward the adequate functional ability of the child. Transcutaneous electrical nerve stimulation (TENS) is widely used, and its efficacy has been studied in adults and children. The therapeutic benefits of TENS in children with RSD have been reported by Kesler et al., who used TENS regularly in their practice, along with physical therapy, which consists of both active and passive physical modalities. The physical therapy program is geared toward individual patients, with the primary goal of maximum participation. It may be necessary to have input from a specialized pediatric physical therapist or occupational therapist for adequate management. Commonly used treatment options for CRPS include desensitization, graduated weight bearing, exercise therapy, graded motor imagery, warm and cold baths, massage therapy, and water emersion therapy.

Medical Therapy

Most medical treatment strategies for children have been extrapolated from adult data. These include pharmacotherapy, regional anesthetics, sympathetic blockade, and neuromodulation. Over counter medications, such as nonsteroidal anti-inflammatory drugs (NSAIDs), are typically trialed by patients and families for initial pain treatment. However, there are mixed data regarding their efficacy. Anti-neuropathic pain medications can be trialed sequentially, although toxicities and side effects should be monitored closely in pediatric patients (see Box 43.4 ).

Tricyclic Anti-depressants

Adults are frequently prescribed tricyclic anti-depressants (TCAs) for the management of NP. Despite the lack of adequately controlled studies in pediatric patients, TCAs are widely prescribed for several forms of NP. Because amitriptyline may cause sedation, it is our practice to use nortriptyline, which appears to have less sedative and fewer anticholinergic side effects. A thorough examination of the cardiovascular system is necessary before instituting TCA treatment because of associated tachydysrhythmia and other conduction abnormalities of the heart, particularly prolonged QT syndrome. ^,

Anti-convulsants

Anti-convulsant medications have been used for several years to manage NP. Although carbamazepine and oxcarbazepine have been used extensively to treat NP, the introduction of gabapentin and pregabalin has revolutionized the world of pain medicine. Despite the lack of controlled trials in children to demonstrate the efficacy of either drug, both of these voltage-gated calcium channel blockers have been used in our clinic with promising results. More controlled trials are needed to better determine the dosing and efficacy of this class of drugs in children with CRPS 1. An important side effect that we have noted in our clinic setting is the potential for increased somnolence and the potential for weight gain. Similar to other anti-convulsant medications, there are concerns regarding mood changes and increased agitation and aggression in adolescents taking gabapentinoids. As such, the Food and Drug Administration (FDA) has issued a warning for increased suicidiality with these medications, and families should be counseled prior to initiating therapy.

Selective Serotonin Reuptake Inhibitors and Serotonin-Norepinephrine Reuptake Inhibitors

Despite the lack of proven efficacy of the use of selective serotonin reuptake inhibitors in the management of pain in children and adolescents, they are occasionally used to treat psychological comorbidities, including depression associated with pain. More recently, serotonin-norepinephrine reuptake inhibitors have been successfully used to treat NP, especially in patients with psychological comorbidity.

Systemic Vasodilators

Several patients with RSD have benefited from the use of vasodilators such as prazosin, nifedipine, and phenoxybenzamine. However, the overwhelming adverse effects of orthostatic hypotension often offset the efficacy of this therapy.

Regional Anesthesia and Sympathetic Blocks

A common treatment for these syndromes is to interrupt the apparent pathologic reflexes by performing sympathetic blocks ( Box 43.5 ). Regional anesthesia, although used often in adults for the diagnosis and management of CRPS, is generally introduced in children after pharmacologic, physical therapy, and cognitive behavior management have been exhausted. Recently, Zerkinow et al. synthesized a review of invasive procedures for children between 8 and 15 years of age with complex regional pain syndromes. They found 36 studies with a total of 173 patients who underwent a procedure, and the procedures varied depending on the decade they were performed. Because of the poor quality of the studies and lack of control, the effectiveness of invasive therapies in pediatric CRPS remains uncertain, and further randomized controlled studies are required. In this section, we discuss the different regional techniques that can be useful in children for the management of CRPS.

Box 43.5Regional Anesthesia for Complex Regional Pain Syndrome Type 1

Intravenous regional anesthesia-guanethidine, bretylium, lidocaine-ketorolac
Epidural analgesia (continuous)
Intrathecal analgesia
Sympathetic chain blocks
- Stellate ganglion blocks
- Lumbar sympathetic blocks
Brachial plexus catheters
Sciatic nerve catheters

Central neuraxial blockade is used in children with severe pain to facilitate the introduction of physical therapy. An indwelling epidural catheter is placed in the lumbar or cervical area and infused with a low-concentration local anesthetic solution, which allows better cooperation from the patient and the parents to introduce a physical therapy regimen. In addition, intrathecal analgesia has been reported to be an effective method for treating refractory CRPS 1 in children. ^,

Bier block has been used for mild to moderate cases of CRPS 1 as a primary modality for providing analgesia and sympathetic blockade. Although a myriad of substances have been used to provide a Bier block, a local anesthetic in combination with either an α ₂ -agonist or an NSAID appears to produce better results. In our case series of children who received intravenous regional anesthesia with lidocaine and ketorolac, we demonstrated a marked improvement in symptoms and the ability to perform physical therapy.

Peripheral nerve blocks are used to facilitate physical therapy while providing a sympathectomy and have become more plausible, especially with the use of ultrasound guidance. Serial peripheral nerve blocks may be performed, which provides pain relief that may outlast the duration of conduction blockade. This may be because of reduced central sensitization, as well as interruption of the circuit established between the nociceptor, central nervous system, and motor unit.

Continuous peripheral nerve blocks (CPNBs) have been reported to be effective in controlling pain and facilitating physical therapy in children with CRPS. Despite such reports, limited data exist regarding the feasibility, safety, and efficacy of CPNBs in children. After perineural catheter placement, a dilute solution of local anesthetic is infused with the view of providing analgesia while allowing physical activity. The catheter is left in place for four to five days; this can be done on an inpatient basis, or the patient may be sent home with a portable infusion device. We prefer sciatic nerve catheter placement for the lower extremities (see Fig. 43.1 ) and interscalene or infraclavicular brachial plexus catheters for the upper extremities. Concurrent physical therapy is indicated to improve the range of motion and function. We instituted physical therapy at the time of provision of a nerve block to enhance the patient’s experience with therapy.

Figure 43.1, Sciatic nerve catheter for the management of complex regional pain syndrome type 1.

Sympathetic blockade was used in children after exhausting the aforementioned techniques. A stellate ganglion block may be performed under ultrasound guidance for upper extremity CRPS (see Fig. 43.2 ), and a lumbar sympathetic block is performed under fluoroscopic guidance for lower extremity CRPS. A crossover trial of fluoroscopically guided lumbar sympathetic blocks demonstrated a decrease in allodynia and pain intensity compared with intravenous injection of lidocaine in adolescents with CRPS.

Figure 43.2, Image of ultrasound guided stellate ganglion blockade.

Neuromodulation via spinal cord stimulation, though commonly performed in adults for refractory cases of CRPS, is very rarely used in the pediatric setting. Spinal cord stimulation has been reported to achieve favorable outcomes in adolescents with therapy-resistant CRPS. The use of peripheral nerve stimulators is gaining ground in the pediatric setting and may benefit children with refractory CRPS with a nerve distribution.

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