Chronic pain: Overview

Abstract
Pain and mental health symptoms frequently co-occur in adolescents, often posing physical, social, and emotional challenges. While previous research has focused on clinician perspectives on chronic pain in isolation, limited knowledge exists on the potential unique challenges these co-occurring symptoms' present to clinicians in providing appropriate support to adolescents. This study examined clinician perspectives on the challenges and barriers to treating adolescents who experience co-occurring pain and mental health symptoms. Using a cross-sectional qualitative online vignette survey, responses were collected from 40 clinicians, including psychologists, physiotherapists, and doctors involved in treating adolescents (11-19 years) who experience co-occurring chronic pain and mental health symptoms. Participants, recruited from several countries, were asked about their perceived challenges to treating adolescents with co-occurring chronic pain and mental health symptoms. Vignettes were analyzed using reflexive thematic analysis. The analysis generated two themes. The first, 'tangled threads', describes how clinicians perceive mistrust from the adolescents based on previous negative clinician encounters and a perceived need to 'undo' this anticipated harm. The second theme 'the difficult-to-pursue integrated approach' depicts how fragmentation and siloed services for pain and mental health hinder effective treatment for adolescents who experience both symptoms. Co-occurring pain and mental health symptoms in adolescents are often initially mismanaged because they do not fit the mould of the services available to treat them, resulting in a more complex presentation to clinicians. The development of a more integrated clinical approach to treating adolescents with co-occurring pain and mental health symptoms is needed. PERSPECTIVE: This study identifies that clinicians perceive they face challenges treating adolescents with co-occurring pain and mental health symptoms, often due to the adolescent's prior clinical experiences and the limited comprehensive treatment options available to them. An integrated approach is urgently needed to tailor care and reduce harm.

Abstract
Objective: Complex Regional Pain Syndrome (CRPS) presents significant diagnostic challenges due to its diverse clinical presentation. This study aims to describe the diagnostic trajectory of patients labeled with CRPS, focusing on referral patterns, application of the Budapest criteria, and accuracy of CRPS diagnosis.

Methods: A retrospective study was conducted of 53 patients treated for CRPS at a peripheral nerve clinic within a tertiary care center (2020-2024). Patient demographics, referral patterns, events leading to CRPS diagnosis, and diagnostic tests were analyzed. Three clinicians (two plastic surgeons, one pain medicine specialist) retrospectively assessed the validity of CRPS diagnoses using the Budapest criteria. Inter-rater reliability (IRR) for CRPS presence and type was calculated using Cohen's kappa (κ).

Results: Among the 53 patients, the median time from the first mention of CRPS to referral to the nerve clinic was 1.3 years (IQR:0.4-3.6). The Budapest criteria had been assessed in 26% of patients pre-evaluation. In 33% of patients labeled with CRPS type I, an inciting nerve injury was identified. Following retrospective assessment, 42% of patients were determined to have CRPS by all raters, 26% were determined not to have CRPS, and 32% showed inconsistent agreement. The IRR for CRPS diagnosis and type ranged from minimal to moderate (κ=0.32-0.72).

Discussion: Our findings highlight variability in the application of the Budapest criteria for CRPS diagnosis, as well as inconsistencies in its retrospective application. Potentially treatable peripheral nerve injuries should be addressed prior to CRPS diagnosis. These findings may help improve early diagnostic assessment in patients with chronic pain.

Abstract
The aim of this systematic review was to identify and critically analyse the tools available for categorising pain as nociceptive, neuropathic and nociplastic pain in children and adolescents. Studies were included if they (i) included children and adolescents with a mean age of 0-24 years old, (ii) examined assessment tools that categorise pain as nociceptive, neuropathic or nociplastic, and (iii) examined the psychometric properties of the tools. Sensitive searches were conducted in five online databases in March 2024. Eligible studies were assessed for risk of bias and quality by two authors using COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) criteria. The search yielded 26 studies for 11 tools. No assessment tool had evidence for all nine recommended psychometric properties. Quantitative Sensory Testing, a tool used to identify signs and symptoms of nociplastic and neuropathic pain, was the most studied tool and had moderate evidence for construct validity, criterion validity and reliability. Three self-reported questionnaires, the Self-reported Leeds Assessment of Neuropathic Symptoms and Signs (S-LANSS), Central Sensitisation Inventory (CSI) and PainDETECT, had moderate evidence for construct validity and show promise as preliminary tools to identify possible neuropathic or nociplastic pain. However, they had low specificity when used in isolation. All assessment methods would benefit from further psychometric evaluation and validation in children and adolescents. PERSPECTIVE: This systematic review highlights the limited validation of pain assessment tools for children and adolescents. While Quantitative Sensory Testing and self-reported questionnaires show promise in identifying pain mechanisms, their applicability remains uncertain. Further psychometric validation is crucial to improve pain assessment and guide personalized treatment in young populations.