Canadian surveillance study of complex regional pain syndrome in children

Interventional pain management of CRPS in the pediatric population: A literature review

Background

Complex Regional Pain Syndrome (CRPS) is a condition that causes persistent and debilitating pain. It is often associated with physical injury but can also occur without identifiable trauma or ongoing injury. There are no published guidelines for CRPS treatment in the pediatric population, but interdisciplinary care, medication, and physical therapy are common approaches. Sometimes, interventional procedures such as regional anesthesia may be required to manage symptoms.

Objective

The objective of this literature review is to explore the different interventional pain management approaches that are currently being used and have shown effectiveness in the management of CRPS in the pediatric population.

Methods

We conducted a comprehensive search strategy with an experienced librarian and input from the study's principal investigator from January 1st, 2000 to April 2nd, 2024. The search was conducted in multiple databases using controlled vocabulary and keywords to identify studies relevant to invasive treatments for pediatric CRPS.

Results

Of 825 studies screened, 27 met inclusion criteria, predominantly case reports (70%). The analysis included 183 patients aged 7-18 years, with female predominance (81.4%). Lower extremities were most commonly affected (70.49%), and most cases (83.06%) were triggered by identifiable trauma. IASP and Budapest criteria, though not validated for pediatric populations, were inconsistently utilized across studies for CRPS diagnosis. Interventional procedures were typically implemented after failed conservative management (92.89%), which included multiple medications (e.g., pregabalin, amitriptyline, NSAIDs) combined with physical and psychological therapy. Multiple interventional procedures were often required to achieve pain relief or functional improvement. Follow-up periods were not reported in most studies and, when reported, were short, limiting the assessment of long-term intervention efficacy.

Conclusions

This review summarizes the different interventional pain management methods utilized to treat pediatric CRPS. While techniques such as continuous epidural anesthesia, lumbar sympathetic blocks, peripheral procedures, and spinal cord stimulation have been safely and successfully used as part of a multimodal treatment strategy, the lack of high-quality evidence and specific protocols for CRPS diagnosis and management in pediatric patients calls for further research.

Pediatric Complex Regional Pain Syndrome With and Without a History of Prior Physical Trauma at Onset

OBJECTIVE

To determine whether differences exist between children with complex regional pain syndrome (CRPS) who identify an inciting physical traumatic event (group T) versus those without such history (group NT).

METHODS

We performed a single-center, retrospective study of children diagnosed with CRPS, 18 years old or younger, presenting between April 2008 and March 2021 and enrolled in a patient registry. Abstracted data included clinical characteristics, pain symptoms, Functional Disability Inventory, psychological history, and Pain Catastrophizing scale for children. Charts were reviewed for outcome data.

RESULTS

We identified 301 children with CRPS, 95 (64%) reported prior physical trauma. There was no difference between the groups regarding age, sex, duration, pain level, function, psychological symptoms, and scores on the Pain Catastrophizing Scale for Children. However, those in group T were more likely to have had a cast (43% vs 23%, P < 0.001). Those in group T were less likely to experience complete resolution of symptoms (64% vs 76%, P = 0.036). There were no other outcome differences between the groups.

DISCUSSION

We found minimal differences in children with CRPS who report a prior history of physical trauma to those who do not. Physical trauma may not play as significant a role as immobility, such as casting. The groups mostly had similar psychological backgrounds and outcomes.

Signs and symptoms of pediatric complex regional pain syndrome -type 1: A retrospective cohort study

Background

Complex regional pain syndrome (CRPS) presents with an array of symptoms that can vary from child to child, making it difficult to diagnose and differentiate from other pain conditions such as chronic musculoskeletal (MSK) pain. Thirteen symptoms and signs are outlined in the Budapest criteria for CRPS (developed and validated for adults) but have not been well described in pediatrics.

Aims

The aim of this study was to describe the signs and symptoms of pediatric CRPS type 1 (CRPS 1) and determine whether a cluster of symptoms can differentiate CRPS 1 from chronic MSK pain.

Methods

A retrospective cohort study of pediatric patients with CRPS 1 and MSK pain in a pediatric pain program was conducted. Descriptive statistics were used to report demographics and pain characteristics. The chi-square test was used to evaluate differences in signs and symptoms between patients with CRPS and MSK pain. A logistic regression model was used to evaluate whether a cluster of symptoms could predict a diagnosis of CRPS 1.

Results

The sample included 187 patients (99 with CRPS 1 and 88 with MSK pain); 81% were female with a mean age 14.1 years. The most prevalent CRPS symptoms were hyperalgesia (54%) and allodynia (52%). A cluster of symptoms (hyperalgesia, color changes, and range of motion) predicted the probability of a diagnosis of CRPS 1.

Conclusions

A cluster of symptoms may be critical in differentiating pediatric CRPS 1 and MSK pain. Future research is needed to determine if this model is valid in external populations and to explore whether a similar model can differentiate CRPS 1 from other pain conditions (e.g., neuropathic pain).

Modern Principles of Diagnosis and Treatment in Complex Regional Pain Syndrome

BACKGROUND

Background: Complex regional pain syndrome (CRPS) is a relatively common complication, occurring in 5% of cases after injury or surgery, particularly in the limbs. The incidence of CPRS is around 5-26/100 000. The latest revision of the International Statistical Classification of Diseases and Related Health Problems (ICD-11) now categorizes CRPS as a primary pain condition of multifactorial origin, rather than a disease of the skeletal system or the autonomic nervous system.

METHODS

Method: Based on a selective search of the literature, we summarize current principles for the diagnosis and treatment of CRPS.

RESULTS

Results: Regional findings in CRPS are accompanied by systemic symptoms, especially by neurocognitive disorders of body perception and of symptom processing. The therapeutic focus is shifting from predominantly passive peripheral measures to early active treatments acting both centrally and peripherally. The treatment is centered on physiotherapy and occupational therapy to improve sensory perception, strength, (fine) motor skills, and sensorimotor integration/ body perception. This is supported by stepped psychological interventions to reduce anxiety and avoidance behavior, medication to decrease inflammation and pain, passive physical measures for reduction of edema and of pain, and medical aids to improve functioning in daily life. Interventional procedures should be limited to exceptional cases and only be performed in specialized centers. Spinal cord and dorsal root ganglion stimulation, respectively, are the interventions with the best evidence.

CONCLUSION

Conclusion: The modern principles for the diagnosis and treatment of CRPS consider both, physiological and psychological mechanisms, with the primary goal of restoring function and participation. More research is needed to strengthen the evidence base in this field.

Spinal cord stimulator for the treatment of central neuropathic pain secondary to cervical syringomyelia: illustrative case

BACKGROUND

Central neuropathic pain (CNP) of the cervical and/or thoracic spinal cord has many etiologies, both natural and iatrogenic. Frequently, CNP is medically refractory and requires surgical treatment to modulate the perception of pain. Spinal cord stimulation is a modality commonly used in adults to treat this type of refractory pain; however, it is rarely used in the pediatric population.

OBSERVATIONS

The authors reported a case involving a common pediatric condition, Chiari malformation type I with syrinx, that led to a debilitating complex regional pain syndrome. The associated life-altering pain was successfully alleviated following placement of a spinal cord stimulator.

LESSONS

CNP, or the syndromic manifestations of the pain (complex regional pain syndrome), can alter an individual's life in dramatic ways. Spinal cord stimulator placement in carefully selected pediatric patients should be considered in these difficult pain treatment paradigms.