Chronic pain: Overview

Abstract
Objective: To explore the short-term and long-term lived experiences of patients with chronic pain and angina pectoris with spinal cord stimulation.

Design: An interpretive qualitative study with thematic analysis of one-off, semistructured interviews, following Braun and Clarke (2006).

Setting: A multidisciplinary, publicly funded pain service in Auckland, New Zealand. Patients usually undergo a comprehensive medical, psychological and functional assessment and an in-house pain management programme before proceeding to spinal cord stimulator implantation.

Participants: Participants implanted with a spinal cord stimulator between 1998 and 2019 who had their stimulator for ≥1 year, purposively sampled to increase the range of ethnicities.

Main outcome: The themes identified from the interviews.

Results: 24 participants with chronic pain of varied aetiology and a median (range) of 5.2 (2.4-23.2) years since stimulator implantation participated. 22 participants had the device in situ, and 2 had been explanted. Five main themes were identified: (1) embodiment: stimulator and body as one; (2) technical factors: batteries and type of stimulation; (3) improved well-being; (4) social connection and (5) healthcare system interaction. Most participants reported pain relief, but many had experienced complications and discomfort. They emphasised the importance of ongoing support from the pain service. Acceptance of pain, coping and embodiment emerged as common motifs across these themes. 21 participants were satisfied with their treatment.

Conclusion: Within the context of a multidisciplinary pain clinic, despite some discomfort and various complications, most participants valued the ongoing reduction of pain achieved with spinal cord stimulation. Timely access to support from the pain service influenced their experience and satisfaction with their stimulators. Acceptance of pain and embodiment of the stimulator helped participants adapt to living with their stimulator, often over many years.

Abstract
Objectives: To identify health professional's perception of barriers, facilitators and training needs when working with children experiencing chronic pain.

Methods: Cross-sectional online survey of health professionals working with children experiencing chronic pain. Survey questions were a range of exploratory open and closed-ended questions, which included yes/no responses, choosing from a list, ranking options and open responses. Quantitative data were analysed using descriptive statistics and percentages; qualitative data were analysed using content analysis.

Results: 180 health professionals took part, of which 44% were physiotherapists. Tertiary hospitals and private practices were most common workplaces. The most frequently reported categories of both barriers and facilitators were workforce and system factors, child factors and parent factors. The most frequently reported confidence areas and development areas were health professional factors, approaches to care and team structure. 75% of participants reported they were moderately to extremely interested in further training in paediatric chronic pain management and indicated a preference for interactive training rather than "passive" learning formats.

Discussion: Health professionals report a diverse range of perspectives when working with children experiencing chronic pain, including perceived barriers and facilitators to care. Most health professionals were interested in future training in paediatric chronic pain management. Future research exploring the parent and child perspective and how these factors present clinically is needed to inform future training opportunities for health professionals working with children experiencing chronic pain.

Abstract
Background: Complex regional pain syndrome (CRPS) is a debilitating and painful condition accompanied by sensory, autonomic, trophic, and/or motor abnormalities. Although CRPS is rare in the general population, the prevalence among individuals at higher risk, particularly posttraumatic and postsurgical patients, remains unknown. This study aims to provide a benchmark that quantifies CRPS prevalence in high-risk groups, and offers insights on potential predictors of developing CRPS.

Methods: We conducted a systematic review and meta-analysis to identify studies reporting prevalence of CRPS after an inciting event (eg, fracture, surgery), specifically 12-month and 24-month prevalence (primary outcomes), as well as 3-month and 6-month prevalence (secondary outcomes). Estimates from individual studies were transformed using double-arcsine transformation, and the resulting estimates with 95% confidence interval (CI) were pooled in a meta-analysis using a random-effects model.

Results: We included 214 articles with data from 2491,378 participants worldwide (35 countries), of which 16,873 had CRPS. The pooled 12-month and 24-month global prevalence was 3.04% (95% CI, 2.64-3.48) and 6.46% (95% CI, 5.46-7.53), respectively. Subgroup analysis and meta-regression were performed to understand the impact of population-dependent (mechanism of injury, type of CRPS), contextual-dependent (socioeconomic status), and methodological-dependent (study design, publication year) factors. The 12-month prevalence was higher in countries with a high human development index (HDI) compared to those with a medium or very high HDI, was higher in participants with a traumatic inciting injury only versus those with surgical injury only or traumatic/surgical injury, and was higher in prospective versus retrospective studies. Meta-regression analysis showed that publication year was a significant moderator, with more recent articles reporting lower 12-month prevalence.

Conclusions: This study provides a benchmark of the global prevalence of CRPS, which anesthesiologists and pain specialists can use to prioritize early diagnosis and identify those at the highest risk for CRPS.