Pain Reports最新文献

Introduction: Movement-evoked pain (MEP) is the primary symptom in patients with knee osteoarthritis (KOA).

Objectives: This study aimed to investigate the contribution of joint structural changes and pain sensitization to the mechanisms of MEP in patients with KOA.

Methods: A total of 86 patients were assessed for demographic characteristics, osteoarthritis severity, Whole-Organ Magnetic Resonance Imaging Score-Hoffa synovitis and bone marrow lesions, pressure pain threshold and temporal summation of pain at the knee and forearm, Central Sensitization Inventory-9, and MEP. In measure of MEP, knee pain was scored using a numerical rating scale (NRS, 0-10) before and every minute during a 6-minute walking test (6MWT), and the MEP index was defined as the change in NRS pain score from baseline to the sixth minute of walking.

Result: On average, pain during 6MWT increased by 1.4 ± 1.5 points on the NRS relative to baseline, with 30.2% of patients showing an increase of 2 points or more. The hierarchical linear regression analysis revealed that Hoffa synovitis, pressure pain threshold at the forearm, and temporal summation of pain at the knee were associated with the MEP index.

Conclusion: The findings of this study suggest that both synovitis and neural mechanisms, such as pain sensitization, play a role in the development of MEP in KOA.

Commentary on: van den Broeke EN, Crombez G, Vlaeyen JWS. Reconceptualizing sensitization in pain: back to basics. PAIN Reports 2024;9:e1125.

Fillingim RB. Redefining sensitization could be a sensitive issue. PAIN Rep 2024;9:e1126.

Introduction: Prior research suggests that African Americans (AAs) have more frequent, intense, and debilitating pain and functional disability compared with non-Hispanic Whites (NHWs). Potential contributing factors to this disparity are physical activity and sedentary behavior, given that AAs are less physically active, and physical activity is associated with antinociception (whereas sedentary behavior is linked to pronociception). However, impact of these factors on pain processing has largely been unexplored in AAs, especially before chronic pain onset.

Objective: This study examined relationships between physical activity, sedentary behavior (sitting time), and laboratory measures of pain and pain modulation in adult AAs. These included heat pain threshold and tolerance, temporal summation of pain (TSP, a marker of central sensitization), and conditioned pain modulation (CPM, a marker of descending pain inhibition).

Methods: Multiple regressions were conducted to examine the effects of physical activity and sitting time on heat threshold and tolerance. Multilevel models were conducted to assess the relationship between physical activity, sitting time, and temporal summation of pain. Additional multilevel models were conducted to assess the relationship between physical activity, sitting time, and conditioned pain modulation.

Results: Higher level of physical activity, but not sitting time, was associated with reduced TSP slopes. Neither physical activity nor sitting time was associated with CPM slopes. No significant relationships between physical activity or sitting time and heat pain threshold or tolerance were detected.

Conclusions: These findings suggest that physical activity is associated with reduced TSP, an effect which may be driven by reduced spinal hyperexcitability in more active individuals. Thus, structural and individual interventions designed to increase physical activity in healthy, young AAs may be able to promote antinociceptive processes (ie, reduced TSP/reduced pain facilitation) potentially protective against chronic pain.

Introduction: Trigeminal neuralgia (TN) is a chronic, debilitating facial pain disease causing stabbing pain attacks in the sensory distribution of the trigeminal nerve. The underlying pathophysiology of TN is incompletely understood, although microstructural abnormalities consistent with focal demyelination of the trigeminal nerve root have been shown in patients with TN. Studies of the cerebrospinal fluid (CSF) in patients with TN suggest an increased prevalence of inflammatory mediators, potentially implicating neuroinflammation in the pathophysiology of TN, as it has been implicated in other chronic pain conditions.

Objectives: This study aimed to further assess the inflammatory profile of CSF in TN.

Methods: Cerebrospinal fluid was collected from 8 medically refractory patients with TN undergoing microvascular decompression surgery and 4 pain-free controls (2 with hemifacial spasm; 2 with normal pressure hydrocephalus). Cerebrospinal fluid was collected from the cerebellopontine angle cistern intraoperatively in the patients with TN. Inflammatory profiles of CSF samples were analyzed using a 71-plex cytokine and chemokine multiplex assay.

Results: Ten inflammatory markers were found to be significantly higher in TN CSF, and no analytes were significantly lower. Elevated factors can be classified into pro-inflammatory cytokines (IL-9, IL-18, and IL-33), chemokines (RANTES and ENA-78), the tumor necrosis factor superfamily (TRAIL and sCD40L), and growth factors (EGF, PDGF-AB/BB, and FGF-2).

Conclusion: This study further supports the notion that neuroinflammation is present in TN, and that multiple molecular pathways are implicated.

This special issue comprised 7 articles from leaders in the field that focus on "big pain data", the large datasets and the associated methods for data analysis that are currently emerging in pain research. This collection of articles highlights the power and potential as well as points of caution that multi-disciplinary research utilising big data and their associated methods and interpretations present for pain research.

Pediatric chronic pain is a complex experience that is often challenging to describe and measure. Multidimensional tools that evaluate the biopsychosocial impact of chronic pain in pediatric patients can help clinicians to prioritize and tailor interdisciplinary pain care; yet, the psychometric value and clinical utility of such tools has not yet been systematically studied in the literature. The purpose of this review was to identify multidimensional biopsychosocial tools used in pediatric chronic pain, synthesize their reliability and validity evidence, and draw on this evidence to describe the relationships between chronic pain and biopsychosocial domains. The search involved 2 phases to (1) identify eligible tools and (2) conduct a measured forward citation search of tool development articles. Tool eligibility was guided by the Multidimensional Biobehavioral Model of Pediatric Pain and study eligibility was focused on primary chronic pain diagnoses unrelated to disease. Data extraction was focused on reliability and validity evidence of eligible tools, guided by the Standards for Educational and Psychological Testing. Results yielded 6 tools that included 64 eligible studies, highlighting 84 significant relationships between pain and functional interference across 11 biopsychosocial variables. All tools were shown to have good internal consistency and evidence of validity, primarily through relationships to other variables. Of the 6 tools, the most brief and easy to use were the most under studied. Further psychometric research is warranted for these tools to investigate their clinical utility and psychometric properties in guiding and prioritizing pain care for children and adolescents.

Introduction: Neuropathic pain (NP) arises from nerve damage or disease, and when not defined, it can impair function and quality of life. Early detection allows for interventions that can enhance outcomes. Diagnosis of NP can be difficult if not properly evaluated. PainDETECT is a NP screening tool developed and successfully used in adults.

Objectives: We evaluated the validity of painDETECT in a pediatric population.

Methods: Adolescents and young adults (10-19 years old) completed painDETECT and quantitative sensory testing (QST), which assessed mechanical allodynia and hyperalgesia, common symptoms of NP. Pain diagnoses, including neuropathic pain (n = 10), were collected through documentation in the medical chart. Descriptive statistics were used to examine age, gender, pain diagnoses, and painDETECT scores. Kruskal-Wallis H tests were conducted to examine differences in QST results across painDETECT categorizations.

Results: Youth with chronic pain (N = 110, M_age = 15.08 ± 2.4 years, N_female = 88) and peers without pain (N = 55, M_age = 15.84 ± 3.9 years, N_female = 39) completed the painDETECT. The painDETECT scores for youth with pain (M = 12.7 ± 6.76) were significantly higher than those for peers without pain (M = 2.05 ± 2.41). PainDETECT demonstrated 80% sensitivity and 33% specificity in a pediatric population. Individuals who screened positively on the PainDETECT had significantly higher mechanical allodynia (M = 0.640 ± 0.994) compared with those who screened negatively (M = 0.186 ± 0.499; P = 0.016).

Conclusion: PainDETECT demonstrated the ability to screen for NP, and QST mechanical allodynia results were consistent with a positive NP screen. Results of the study offer preliminary support for the ongoing assessment of the painDETECT as a brief, inexpensive, and simple-to-use screening tool for pediatric patients with primary pain complaints.

Introduction: Despite advancements in implanted hardware and development of novel stimulation paradigms in Spinal Cord Stimulation (SCS), real world evidence suggests a large variation in patient reported outcomes and a proportion of patients are later explanted due to loss of analgesia. Possible predictors for outcome have been explored in smaller short-term evaluations, but few clinically applicable robust measures for long term outcome have emerged.

Methods: We performed a comprehensive retrospective study based on an assembled patient-level aggregated database from multiple local and national registries in Sweden. Variables associated with risk of explantation (due to insufficient analgesia) and analgesic effect was analyzed using a Cox regression analysis and an ordered logit regression model, respectively.

Results: We found the accumulated risk of explantation due to loss of analgesia to be 10% and 21% at two and ten years follow up, respectively. The use of 10 kHz spinal cord stimulation (compared with Tonic waveform; p = 0.003), and being 60 years or older (reference 18-40 years; p = 0.003) were associated with an increased risk of explantation.At a mean follow up at 1 year, 48% of patients reported a pain intensity reduction from baseline of at least 30%. Secondary (p = 0.030) and post-secondary (p = 0.001) education (compared with primary education) was associated with an increased probability of successful patient reported outcomes.

Conclusion: This study suggests that a higher educational level and being employed are associated with successful treatment outcome in patients with chronic pain treated with SCS in Sweden.