Complex regional pain syndrome in children: asking the right questions

Sensory Function and Psychological Factors in Children With Complex Regional Pain Syndrome Type 1

OBJECTIVE

To assess thermal-sensory thresholds and psychosocial factors in children with Complex Regional Pain Syndrome Type 1 (CRPS-I) compared to healthy children.

METHODS

We conducted quantitative sensory testing on 34 children with CRPS-I and 56 pain-free children. Warm, cool, heat, and cold stimuli were applied to the forearm. Children with CRPS-I had the protocol administered to the pain site and the contralateral-pain site. Participants completed the self-report Behavior Assessment System for Children.

RESULTS

Longer pain durations (>5.1 months) were associated with decreased sensitivity to cold pain on the pain site (P = .04). Higher pain-intensity ratings were associated with elevated anxiety scores (P = .03). Anxiety and social stress were associated with warmth sensitivity (both P < .05) on the contralateral-pain site.

CONCLUSIONS

Pain duration is an important factor in assessing pediatric CRPS-I. Hyposensitivity in the affected limb may emerge due to degeneration of nociceptive nerves. Anxiety may contribute to thermal-sensory perception in childhood CRPS-I.

Recovery from acute pediatric complex regional pain syndrome type I after ankle sprain by early pharmacological and physical therapies in primary care: a case report

Background

Complex regional pain syndrome type I (CRPS I) in children is a serious condition disrupting the family and school life of patients with the condition after it fully develops. It has been emphasized that early diagnosis is closely associated with earlier reduction of pain leading to preferable outcomes.

Objectives

To report a case of acute CRPS I in a boy who was found to develop this condition by a routine visual analog scale (VAS) pain monitoring and who recovered from CRPS I at an early phase by prompt pharmacological, physical, and educational therapies.

Study design

Case report.

Case report

A 12-year-old boy sprained his left ankle while playing soccer and was referred to our clinic 4 days after the injury. At the first visit, he could walk, reporting motion pain with a VAS scale of 80 mm. On day 5, pain intensity increased to 100 mm, and a diagnosis of acute CRPS I was made. On day 7, he could not move the injured ankle; therefore celecoxib and pregabalin were administered, and physical and educational therapies started. On day 35, pain intensity was 0 mm and he could walk and run normally.

Conclusion

Routine monitoring of VAS for every patient in pain is useful to discover an abnormal transition of VAS, enabling the early diagnosis of CRPS I. Inflammation and peripheral or central sensitization are postulated for early development of CRPS I. The present case suggested a combination of physical therapy and pharmacological intervention with celecoxib and pregabalin reduced peripheral and central sensitization.

Complex regional pain syndrome type I in children: What is new?

Complex regional pain syndrome type I (CRPS-I), although first described by the French surgeon Ambroise Paré as far back as the 16th century, nevertheless remains shrouded in mystery. The most common symptoms are pain in an entire hand or foot, allodynia, functional impairment induced by the pain, local oedema and skin color changes and transient sweating abnormalities. Most cases occur after a minor injury (i.e., a sprain or fracture), although there may be no identifiable triggering event, particularly in children. Primarily cold CRPS-I is by far the most common variant in children. Development of the Budapest criteria has benefited the diagnosis. These criteria are clinical and no specific diagnostic investigation is available. In vitro and in vivo studies have established that several pathogenic mechanisms can be involved concomitantly. However, there is no satisfactory explanation to the full clinical spectrum. Blood tests and imaging studies are useful for ruling out other diagnoses then monitoring the course of the condition, which may involve the development of demineralisation or osteopenia. High-resolution peripheral quantitative computed tomography may be helpful, as it provides quantitative assessments of the cortical and trabecular bone. CRPS-I has several specific characteristics in children compared to adults and whether the condition is the same entity in these two age groups is a legitimate question. The optimal management involves an early diagnosis followed by a multidisciplinary management programme of functional rehabilitation therapy and cognitive behavioral therapy. Analgesics are useful only during the phase of acute pain and to facilitate physical therapy. Studies in adults showed that bisphosphonates were effective within the first 12 months after symptom onset and calcitonin in longer-lasting cases. No high-quality clinical research studies into the aetiopathogenesis and treatment of CRPS-I in children and adolescents are available to date.

Complex Regional Pain Type 1

Complex regional pain syndrome is increasingly recognized in the pediatric population. Owing to the nature of presentation with pain, many of these children present to the emergency setting at different stages of the syndrome with or without numerous prior interactions with health professionals. Complex regional pain syndrome type 1 (CRPS1) is a clinical syndrome characterized by amplified musculoskeletal limb pain that is out of proportion to the history and physical findings, or pain due to non-noxious stimuli (allodynia/hyperalgesia), and accompanied by one or more signs of autonomic dysfunction. Differential diagnosis may include significant trauma (eg, fractures), inflammatory conditions, malignancies, and systemic illness. The diagnosis is clinical. The treatment goals for CRPS1 are restoration of function and relief of pain. Education, physical, and occupational therapy with psychotherapy and defined goals of achievement with reward are the mainstay of treatment for this population. Most children with CRPS1 will have a favorable outcome.

Current concepts in management of pain in children in the emergency department

Pain is common in children presenting to emergency departments with episodic illnesses, acute injuries, and exacerbation of chronic disorders. We review recognition and assessment of pain in infants and children and discuss the manifestations of pain in children with chronic illness, recurrent pain syndromes, and cognitive impairment, including the difficulties of pain management in these patients. Non-pharmacological interventions, as adjuncts to pharmacological management for acute anxiety and pain, are described by age and development. We discuss the pharmacological management of acute pain and anxiety, reviewing invasive and non-invasive routes of administration, pharmacology, and adverse effects.

Invasive Treatments for Complex Regional Pain Syndrome in Children and Adolescents

This review aimed to synthesize the current evidence on the effectiveness of invasive treatments for complex regional pain syndrome in children and adolescents. Studies on children and adolescents with complex regional pain syndrome that evaluated the effects of invasive treatment were identified in PubMed (search March 2013). Thirty-six studies met the inclusion criteria. Articles reported on a total of 173 children and adolescents with complex regional pain syndrome. Generally, many studies lack methodological quality. The invasive treatments applied most often were singular sympathetic blocks, followed by epidural catheters and continuous sympathetic blocks. Rarely, spinal cord stimulation and pain-directed surgeries were reported. An individual patient frequently received more than one invasive procedure. Concerning outcome, for approximately all patients, an improvement in pain and functional disability was reported. However, these outcomes were seldom assessed with validated tools. In conclusion, the evidence level for invasive therapies in the treatment of complex regional pain syndrome in children and adolescents is weak.