Pre-existing Pain Research Articles

How timing and preexisting pain affect outcomes of TMR: a systematic review

Introduction: Targeted muscle reinnervation (TMR) is increasingly common in the care of major limb amputation to limit amputation-related pain. This review aims to elucidate how chronic pain states and length of delay prior to TMR affect its success and outcomes. Methods: Manuscripts were collected from three databases. Articles were first screened and excluded based on exclusion criteria. The remaining manuscripts were independently reviewed to determine inclusion. Article and patient demographics, as well as pain outcomes, were extracted. Data were analyzed based on pain condition, amputation vs. neuroma, and time from amputation/injury to surgery. Results: The literature search yielded 723 articles, with 41 meeting the inclusion criteria. Twenty-one articles included patients with residual limb pain (RLP) and phantom limb pain (PLP), including 14 on amputation and 6 on neuroma excision. Five articles included cancer-related amputation. Complex Regional Pain Syndrome (CRPS) was discussed in 3 articles, ischemia or infection in 2 articles, and neurofibromatosis 1 in 1 article. Twenty-two articles described TMR at the time of amputation. Conclusions: TMR is effective at preventing neuroma formation and limiting pain when performed at the time of amputation. Delayed patients had a greater improvement in RLP but less of an improvement in PLP, when assessed against immediate TMR patients who were compared to non-TMR standard amputees. In the presence of chronic pain states, such as CRPS, there is also improved analgesia. However, current clinical data are limited, indicating a need for further research into the use of TMR for chronic pain management.

Patient-reported outcomes, postoperative pain and pain relief after day case surgery (POPPY): methodology for a prospective, multicentre observational study.

In the UK, approximately 70% of surgical procedures are undertaken as day-cases. Little information exists about recovery from day-case surgery, yet international data highlights patients are at risk of developing significant longer-term health problems including chronic post-surgical pain and persistent postoperative opioid use. The Patient-reported Outcomes, Postoperative Pain and pain relief after daY case surgery (POPPY) study was a national prospective multicentre observational study, measuring short- and longer-term patient-reported outcomes, postoperative pain and pain relief after day-case surgery. This was a collaborative project led by resident anaesthetists under the Research and Audit Federation of Trainees umbrella. Adult day-case surgical patients were recruited on the day of surgery. Baseline data including patient characteristics; procedure details; pre-operative analgesic use; pre-existing pain; and quality of life scores were recorded. Patients were followed up through automated short message service messages. Short-term (postoperative days 1, 3 and 7) outcomes included: quality of recovery; pain severity; impact of pain on function; and analgesic use. Longer-term outcomes (postoperative day 97) included: quality of life; analgesic use; incidence of chronic post-surgical pain; and incidence persistent postoperative opioid use. Additional outcomes were completed by those patients with chronic post-surgical pain and persistent postoperative opioid use, with 30 patients recruited to a qualitative semi-structured interview study exploring postoperative expectations, recovery, postoperative pain and opioid use. An embedded pilot study at four sites recruited 129 patients. Responses to the automated short message service were gained from 129 patients (100%) at day 1; 116 (89.9%) at day 3; 108 (83.7%) at day 7; and 77 (59.7%) at day 97 postoperatively. The pilot enabled refinement of the methods and processes before the national roll out. This paper outlines the methods for the POPPY study, the largest UK multicentre prospective observational study considering short- and longer-term outcomes following day-case surgery.

Early Postoperative Pain Course following Primary and Secondary Targeted Muscle Reinnervation: A Temporal Description of Pain Outcomes.

Targeted muscle reinnervation (TMR) is an effective surgical treatment of neuropathic pain for amputees. However, limited data exist regarding the early postoperative pain course for patients who undergo either primary (<14 days since amputation) or secondary (≥14 days) TMR. This study aims to outline the postoperative pain course for primary and secondary TMR during the first 6 postoperative months to aid in patient education and expectation management. Patients were eligible if they underwent TMR surgery between 2017 and 2023. Prospectively collected patient-reported outcome measures of pain scores, Pain Interference, and Pain Intensity were analyzed. Multilevel mixed-effects models were utilized to visualize and compare pain courses between primary and secondary TMR patients. A total of 203 amputees were included, with 40.9% being primary and 59.1% being secondary TMR patients. Primary TMR patients reported significantly lower pain scores over the full 6-month postoperative trajectory (p < 0.001) compared with secondary TMR patients, with a difference of Δ -1.0 at the day of TMR (primary = 4.5, secondary = 5.5), and a difference of Δ -1.4 at the 6-month mark (primary = 3.6, secondary = 5.0). Primary TMR patients also reported significantly lower Pain Interference (p < 0.001) and Pain Intensity scores (p < 0.001) over the complete trajectory of their care. Primary TMR patients report lower pain during the first 6 months postoperatively compared with secondary TMR patients. This may reflect how pre-existing neuropathic pain is more challenging to mitigate through peripheral nerve surgery. The current trends may assist in both understanding the postoperative pain course and managing patient expectations following TMR. Therapeutic - IV.

Effect of Transcutaneous Auricular Vagus Nerve Stimulation on Conditioned Pain Modulation in Trigeminal Neuralgia Patients.

Conditioned pain modulation (CPM) is a quantitative estimation of the capacity for endogenous pain modulation. Reduced CPM enables chronic painful event development or exacerbates pre-existing pain symptoms. Emerging reports indicate that patients with trigeminal neuralgia (TN) have dysregulated endogenous pain modulation. Transauricular vagus nerve stimulation (taVNS) is known to alleviate both acute and chronic pain symptoms. Its role in modulation or management of TN remains unknown. Here, we evaluated the taVNS efficacy in modulating CPM among TN patients. Conclusions from this investigation may facilitate establishment of novel non-invasive adjunctive approaches to treating TN patients. All research work was conducted at the First Affiliated Hospital of the University of Science and Technology of China (Anhui Provincial Hospital). In all, we recruited 62 study participants, 31 TN patients and 31 healthy volunteers, for a 2-day experimental test. At the beginning of the experiment (Day 1), all subjects received 30min of active taVNS. On Day 2, they received sham taVNS with the same duration and intensity. Meanwhile, technicians documented participant pressure pain thresholds (PPT) and CPM values at baseline, and at 15 and 30min post-active or sham taVNS. A 30-min active taVNS exposure substantially elevated the PPT and CPM effect (P<0.05) among TN patients, and we also observed a notable rise in the PPT and CPM effect (P<0.05) among healthy controls. Additionally, there were no serious adverse events from the administered treatment. Exposure to 30min of active taVNS strongly augmented the CPM effect and elevated the PPT among TN patients and healthy controls. These effects were not observed with sham stimulation. Despite the limitations inherent to survey studies, such as duration and compliance biases, we consider that taVNS is a promising, safe, and cost-effective therapy. In future investigations, we recommend assessment of long-term taVNS application and its effects on CPM and clinical pain. ChiCTR2300078673 ( www.Chictr.org.cn ).

An Ergonomic Golf Grip Leads to Lower Forearm Muscle Activity - A Prospective Case Series of 30 Right-Handed Amateur and Professional Golfers

BackgroundThe elbow is a common site for overuse injuries in golfers. Tendinopathies, such as medial and lateral epicondylitis, are frequently diagnosed in amateur and professional golfers. The aim of our study was to determine the effect of an ergonomic golf grip on forearm muscle activity during the five phases of the golf swing.MethodsThirty right-handed golfers with a mean age of 32 years (range, 18–70 years) and a mean handicap of 15 (range, 0–43) performed 10 golf swings with a standard and ergonomic golf grip respectively. The mean and maximum muscle activity of the Musculus (M.) extensor carpi radialis brevis (ECRB), M. flexor carpi ulnaris (FCU), M. pronator teres (PT) and M. biceps brachii (BB) of the lead and trail arms were assessed during the five phases of the golf swing using surface electromyography (EMG). Subgroup analyses were performed regarding sex, playing ability (handicap < 10 vs. ≥10), weekly playing time (≤ 5 h, 5–20 h, > 20 h) and preexisting elbow pain during golfing (VAS < 2 vs. VAS ≥ 2). Significance was set at p < 0.05.ResultsAn ergonomic golf grip resulted in a reduction in muscle activity in at least one but up to three consecutive phases of the golf swing for the ECRB, FCU and PT of the lead arm and for the PT of the trail arm. Amateurs, a playing time < 20 h per week and golfers without preexisting elbow pain were factors that were associated with greater reductions in muscle activity.ConclusionForearm muscle activity can be decreased using an ergonomic golf grip, indicating the possible role of an ergonomic golf grip as a preventive measure against overuse syndromes such as medial and lateral epicondylitis.Trial registration numberThis study was retrospectively registered at the German Clinical Trials Register DRKS-ID: DRKS00033732 (01/03/2024).

Pain experience with outpatient hysteroscopy: A prospective cohort study

BackgroundAbnormal uterine bleeding (AUB) affects women of all ages and is one of the most common reasons for referral to a gynaecological clinic. Operative hysteroscopic procedures allow for a see-and-treat approach to AUB, and these techniques have been shown to be feasible and acceptable in the outpatient setting. ObjectiveTo assess if there is an increase in pain scores for women who are undergoing an operative hysteroscopic procedure with Myosure LITE® (Hologic; mechanical hysteroscopic tissue removal system) compared to outpatient diagnostic hysteroscopy alone. Study designA prospective cohort study was performed. All participants attending the outpatient hysteroscopy clinic at Mercy Hospital for Women completed a pre-and post-procedure questionnaire. This included a visual analogue scale (VAS) for any pre-existing pain, anticipated pain, and actual pain experienced during procedure. Factors influencing overall satisfaction and willingness to attend again were also assessed. Data was entered into RedCap® for analysis. A difference in VAS of 10 mm or more was considered clinically significant. An alpha of p < 0.05 was assigned for statistical significance. ResultsBetween February 2020 and November 2022, 208 women underwent outpatient diagnostic hysteroscopy followed by an operative hysteroscopy with MyoSure®. To allow for standardisation of analgesia, only participants who had a cervical block before their Myosure® procedure were included for analysis (n = 111). There was statistical evidence (t(111) = 2.36, p = 0.02) of a lower mean VAS pain score for operative Myosure (36.5 mm, 95 % CI: 31.1–41.8 mm) compared to outpatient diagnostic hysteroscopy (44.1 mm, 95 % CI: 39.0–49.2 mm). The mean difference in VAS pain score was estimated as 7.7 mm (95 % CI: 1.2–14.1 mm) lower for Myosure compared to hysteroscopy. Given the threshold for clinical significance was considered as 10 mm difference in VAS, the variance in pain scores is under the likely clinically significant range. There was no significant difference in pain scores for diagnostic hysteroscopy with or without paracervical block (mean difference = 1.42; 95 % CI: −6.35 to 9.20). There was no association between pre-existing pain, and actual pain for hysteroscopy, or Myosure (p = 0.997 and p = 0.065 respectively). The anticipated pain score was weakly associated with actual pain during the operative Myosure procedure (p = 0.02), and with outpatient diagnostic hysteroscopy (p = 0.019). ConclusionOutpatient hysteroscopy procedures are generally well tolerated. The pain experience with operative Myosure was less than that reported during the diagnostic hysteroscopy by the same patient although this is unlikely of clinical significance. Importantly, Myosure was not more painful than the initial diagnostic procedure, and most patients were satisfied with the outcome and would choose to have the procedure again in an outpatient setting. This is in keeping with other studies which have shown a high degree of patient tolerance and satisfaction with this approach.

New persistent opioid use following robotic-assisted, laparoscopic and open surgery inguinal hernia repair

IntroductionPost-operative prescription opioid use is a known risk factor for persistent opioid use. Despite the increased utilization of robotic-assisted surgery (RAS) for inguinal hernia repair (IHR), little is known whether this minimally invasive approach results in less opioid consumption. In this study, we compare long-term opioid use between RAS versus laparoscopic (Lap) versus open surgery for IHR.MethodsA retrospective cohort study of opioid-naïve patients who underwent outpatient primary IHR was conducted using the Merative™ MarketScan® (Previously IBM MarketScan®) Databases between 2016 and 2020. Patients not continuously enrolled 180 days before/after surgery, who had malignancy, pre-existing chronic pain, opioid dependency, or invalid prescription fill information were excluded. Among patients exposed to opioids peri-operatively, we assessed long-term opioid use as any opioid prescription fill within 90 to 180 days post-surgery. Secondary outcomes were controlled substance schedule II/III opioid fill, and high-dose opioid fill defined as > 50 morphine milligram equivalent per day. An Inverse-probability of treatment weighted logistic regression was used to compare outcomes between groups with p-value of < 0.05 considered statistically significant.ResultsA total of 41,271 patients were identified (2070 (5.0%) RAS, 16,704 (40.5%) Lap, and 22,497 (54.5%) open surgery). RAS was associated with less likelihood of prescription fills for any opioid (OR 0.78, 95% CI 0.60 to 0.98 versus Lap; OR 0.67, 95% CI 0.52 to 0.85 versus open), and schedule II/III opioid (OR 0.74, 95% CI 0.56 to 0.96 versus Lap; OR 0.68, 95% CI 0.51 to 0.88 versus open), but comparable high-dose opioid fill (OR 0.95, 95% CI 0.54 to 1.55 versus Lap; OR 0.96, 95% CI 0.56 to 1.52 versus open). Lap and open surgery had no significant difference.ConclusionIn this cohort of patients derived from a national commercial claims dataset, patients undergoing RAS had a decreased risk of long-term opioid use compared to laparoscopic and open surgery patients undergoing IHR.

Incidence and risk factors of new persistent opioid use after surgery and trauma: A systematic review

BackgroundPersistent opioid use (POU) can occur with opioid use after surgery or trauma. Current systematic reviews include patients with previous exposure to opioids, meaning their findings may not be relevant to patients who are opioid naïve (i.e. Most recent exposure was from surgery or trauma). The aim of this review was to synthesise narratively the evidence relating to the incidence of, and risk factors for POU in opioid-naïve surgical or trauma patients.MethodStructured searches of Embase, Medline, CINAHL, Web of Science, and Scopus were conducted, with final search performed on the 17th of July 2023. Searches were limited to human participants to identify studies that assessed POU following hospital admission due to surgery or trauma. Search terms relating to ‘opioid’, ‘analgesics’, ‘surgery’, ‘injury’, ‘trauma’ and ‘opioid-related disorder’ were combined. The Newcastle–Ottawa Scale for cohort studies was used to assess the risk of bias for studies.ResultsIn total, 22 studies (20 surgical and two trauma) were included in the analysis. Of these, 20 studies were conducted in the United States (US). The incidence of POU for surgical patients 18 and over ranged between 3.9% to 14.0%, and for those under 18, the incidence was 2.0%. In trauma studies, the incidence was 8.1% to 10.5% among patients 18 and over. Significant risk factors identified across surgical and trauma studies in opioid-naïve patients were: higher comorbidity burden, having pre-existing mental health or chronic pain disorders, increased length of hospital stay during the surgery/trauma event, or increased doses of opioid exposure after the surgical or trauma event. Significant heterogeneity of study design precluded meta-analysis.ConclusionThe quality of the studies was generally of good quality; however, most studies were of US origin and used medico-administrative data. Several risk factors for POU were consistently and independently associated with increased odds of POU, primarily for surgical patients. Awareness of these risk factors may help prescribers recognise the risk of POU after surgery or trauma, when considering continuing opioids after hospitalisation. The review found gaps in the literature on trauma patients, which represents an opportunity for future research.Trial registrationPROSPERO registration: CRD42023397186.

Investigating the fluctuating nature of post-COVID pain symptoms in previously hospitalized COVID-19 survivors: the LONG-COVID-EXP multicenter study.

This cohort study used Sankey plots and exponential bar plots for visualizing the fluctuating nature and trajectory of post-COVID pain in previously hospitalized COVID-19 survivors. A cohort of 1266 subjects hospitalised because of COVID-19 during the first wave of the pandemic were scheduled for a telephone interview at 8.4 (T1), 13.2 (T2), and 18.3 (T3) months in average after hospitalization for collecting data about post-COVID pain. Patients were asked for about pain symptomatology that was attributed to the infection. Hospitalization and clinical data were collected from medical records. The prevalence of myalgia as COVID-19-associated symptom was 29.82% (n = 389) at hospitalization (T0). The prevalence of post-COVID pain was 41.07% (n = 520) at T1, 34.29% (n = 434) at T2, and 28.47% (n = 360) at T3. The recovery exponential curve revealed a decrease trend visualizing that post-COVID pain improved over the time span investigated. Pain in the lower extremity and widespread pain were the most prevalent locations. Female sex (OR 1.507, 95% CI 1.047-2.169), pre-existing pain symptoms (OR 1.724, 95% CI 1.237-2.403), headache as onset-symptom (OR 2.374, 95% CI 1.550-3.639), days at hospital (OR 1.012, 95% CI 1.000-1.025), and presence of post-COVID pain at T1 (OR 13.243, 95% CI 9.428-18.601) were associated with post-COVID pain at T2. Only the presence of post-COVID pain at T1 (OR 5.383, 95% CI 3.896-7.439) was associated with post-COVID pain at T3. Current results show a fluctuating evolution with a decreasing tendency of post-COVID pain during the first years after hospitalization. The development of post-COVID pain soon after SARS-CoV-2 infection predispose for long-lasting chronic pain.

Development and validation of a pain scale in guinea pig (Cavia porcellus)

BackgroundThis study aimed to develop and validate a pain assessment scale for guinea pigs to be performed in clinics by veterinarians. The scale was established using pre-existing pain scales from other species and was based on signs expressed by guinea pigs in pain already identified in the literature. The scale consists of 14 descriptors grouped into four categories: appearance, functional, physiological and behavioral. Each item on the scale was assigned a score based on the observation and handling of the animals. The total score obtained ranged from 0 to 26, with more intense pain scoring higher. MethodsFifty-eight adult guinea pigs presenting at the authors' Teaching Hospital between March 2021 and November 2022 were assessed. Guinea pigs were filmed during their consultation and an information sheet was completed. The information sheet provided details on the animals' appetite, fecal production, and behavior at home. The videos and corresponding information sheets were then reviewed to attribute a pain score to each animal. The pain scores were measured twice by a same observer one month apart to assess repeatability and by a second observer to assess reproducibility. The validity was assessed by correlating the pain scores given by the novel scale with scores using a numerical rating scale (NRS) as a gold standard method. ResultsThe initial Cronbach's alpha obtained was 0.77, which was satisfactory. However, it highlighted that items concerning pruritus and spasmodic movements should be deleted to strengthen internal consistency. Then, Lin's coefficient and Bland and Altman's graphical method highlighted that the scale had an almost strong repeatability and intra-operator reproducibility. Moreover, the correlation between pain intensities obtained with the novel scale and the scores given using NRS was correct (Kappa = 0.72). The specificity was 87.5%, but the sensitivity of the scale was 52.0%. Each item's repeatability and reproducibility were assessed to identify items that would benefit from added clarification. ConclusionOur work is the first step in establishing a pain scale in guinea pigs. However, it should not yet be used in a clinical context. Indeed, the scale was not good at detecting pain when a guinea pig was actually painful. Further studies, including improvement of certain items and testing a larger sample of animals, are ongoing.

The effect of COVID-19 on pain control in patients with a neurostimulator in situ- a retrospective study.

De-novo chronic neuropathic pain following COVID-19 is widely recognised. However, there are currently no published studies investigating the effect of SARS-CoV-2 infection on patients with pre-existing neuropathic pain who have required spinal cord stimulator (SCS) implantation. Here, the authors aimed to analyse outcomes in their institution's patients who had spinal cord stimulator (SCS) implantation or revision procedures to the system over a 5-year period. Specifically, the short-term and long-term outcomes of patients who contracted COVID-19 during the follow-up period were compared to the control group of patients who did not. Patients included in this study had spinal cord stimulator implantation (de-novo and revision procedures) between 1 January 2017 and 31 January 2022, for neuropathic pain of any aetiology. Patients deemed eligible for the study were invited to participate in a telephone survey through which clinical outcome data were collected. Pain scores were assessed with a modified form of the Brief Pain Inventory (BPI). Of 91 patients, 48 (52.7%) had contracted COVID-19 by the time of the survey. Patients who contracted COVID-19 had significantly worse BPI scores in the 'Least pain' domain following their infection and at time of the survey, when compared to their score 6 months after the operation. 22.9% (n = 11) of the patients who contracted COVID-19 experienced a change in their symptoms following their infection. Within this sub-group, there was a statistically significant deterioration in BPI scores in 10/11 domains following their infection and in 2/11 domains at time of the survey. Worsening severity of COVID-19 symptoms was not associated with worse BPI scores. Infection with SARS-CoV-2, in a significant proportion of patients with an SCS in situ, causes at least a transient deterioration in pain control. Further prospective multicentre studies are indicated to establish the prevalence of this phenomenon.

The Association of Body Mass Index and Early Outcomes Following Orthognathic Surgery

The existing data on the link between body mass index (BMI), operative characteristics, and surgical outcomes across orthognathic surgery are limited. The purpose was to measure the association between BMI and early postoperative outcomes in orthognathic surgery. This is a retrospective cohort study of patients (n=118) aged > 14years undergoing bimaxillary orthognathic surgery between 2015 and 2018 by a single surgeon within the Kaiser Permanente Northern California-integrated healthcare system. Patients undergoing unilateral or additional procedures, history of prior orthognathic surgery, or pre-existing pain conditions were excluded. The predictor variable was BMI measured as a continuous (kg/m2) and categorical variable (underweight/normal, overweight, obese). The primary outcome variables were additional postoperative antibiotics, increased postoperative visits, wound dehiscence, and wound infection. The secondary outcome variables were total operative and anesthesia time. The demographic covariates included age, sex, and race/ethnicity. The clinical covariates included history of obstructive sleep apnea, Mallampati score, tobacco use, American Society of Anesthesia classification, thyromental distance, history of difficult intubation, and Angle's classification. Bivariate and multivariate analyses were performed to measure the associations between BMI and the primary and secondary outcomes. Multivariable logistic regression analyses were used to measure associations between BMI and the postoperative outcomes. Statistical significance was defined as P<.05. The study sample was composed of 118 subjects with a mean age of 26.91years (standard deviation 9.43). Forty-seven percent (n=55) were male, and the mean BMI was 25.13 (standard deviation 5.19). BMI category was significantly associated with age, with increasing age associated with higher BMI category (P=.02). According to the bivariate and multivariable logistic regression analyses, controlling for age, race/ethnicity, BMI, and total operative time, increased total operative time was associated with additional postoperative antibiotics (odds ratio=1.03, 95% confidence interval: 1.01, 1.05), and increased postoperative appointments (odds ratio=1.02, 95% confidence interval: 1.01, 1.04). No significant association between BMI and other clinical or operative characteristics was seen aside from American Society of Anesthesia classification. Elevated BMI was not associated with worsened operative characteristics or postoperative outcomes. This supports the suitability of orthognathic surgery in a BMI-diverse population.

Current and future advances in practice: aromatase inhibitor-induced arthralgia.

Aromatase inhibitors (AIs) have shown great success as adjuvant therapy for post-menopausal women with hormone receptor-positive breast cancers. AI-induced arthralgia (AIA) is a frequent AI toxicity contributing to non-adherence and discontinuation. This review aims to understand current knowledge of AIA. The mean incidence of AIA was 39.1% and the mean discontinuation of AI therapy due to AIA was 9.3%. Most of the AIAs were non-inflammatory. A shorter time since the last menstrual period and pre-existing joint pain were risk factors. Vitamin D3 supplementation may be a preventative measure and treatment with duloxetine, acupuncture and/or exercise is supported by large randomized controlled trials. There was consistent improvement in AIAs with switching to an alternate AI, and this could additionally allow continuation of cancer treatment with AI. Further research is needed to identify predictive biomarkers, better characterize AIA subcategories and study more reliable therapeutic options.

Different pain phenotypes are associated with anti-Caspr2 autoantibodies

Autoantibodies against contactin-associated protein 2 (Caspr2) not only induce limbic autoimmune encephalitis but are also associated with pain conditions. Here, we analyzed clinical data on pain in a large cohort of patients included into the German Network for Research in Autoimmune Encephalitis. Out of 102 patients in our cohort, pain was a frequent symptom (36% of all patients), often severe (63.6% of the patients with pain) and/or even the major symptom (55.6% of the patients with pain). Pain phenotypes differed between patients. Cluster analysis revealed two major phenotypes including mostly distal-symmetric burning pain and widespread pain with myalgia and cramps. Almost all patients had IgG4 autoantibodies and some additional IgG1, 2, and/or 3 autoantibodies, but IgG subclasses, titers, and presence or absence of intrathecal synthesis were not associated with the occurrence of pain. However, certain pre-existing risk factors for chronic pain like diabetes mellitus, peripheral neuropathy, or preexisting chronic back pain tended to occur more frequently in patients with anti-Caspr2 autoantibodies and pain. Our data show that pain is a relevant symptom in patients with anti-Caspr2 autoantibodies and support the idea of decreased algesic thresholds leading to pain. Testing for anti-Caspr2 autoantibodies needs to be considered in patients with various pain phenotypes.

Association of peri-operative prescription of non-steroidal anti-inflammatory drugs with continued prescription of opioids after total knee arthroplasty: a retrospective claims-based cohort study.

Non-steroidal anti-inflammatory drugs (NSAIDs) are one of the mainstays of multimodal pain management. While effective for acute pain control, recent pre-clinical evidence has raised concerns regarding an association between NSAIDs and chronic pain and potential opioid use. Our objective was to explore the association between peri-operative use of prescription NSAIDs and the need for continued opioid prescriptions lasting 90-180 days in previously opioid-naïve patients undergoing total knee arthroplasty. A database of health claims in the USA was used to identify all opioid-naïve adult patients who underwent primary knee arthroplasty between January 2010 and October 2021. We evaluated the magnitude of association between peri-operative prescription NSAID claims and claims for opioids at 90 days postoperatively using multivariable logistic regression models. Secondary outcomes included: the magnitude of association between peri-operative NSAID prescription and claims for opioids at 180 days postoperatively; and identifying other potential factors associated with opioid claims at 90 days postoperatively. After risk adjustment using multivariable logistic regression models in the 789,736-patient cohort, the adjusted odds ratio (95%CI) for a continuous claim of opioids at 90 and 180 days postoperatively among patients with a peri-operative NSAID prescription within 30 days was 1.32 (1.30-1.35), p < 0.001; and 1.12 (1.10-1.15), p < 0.001, respectively. This estimate of effect remained robust at 90 days after accounting for known potential confounders, including pre-existing knee pain and acute postoperative pain severity. Similar analysis of other pain medications (e.g. paracetamol) did not detect such an association. This population-based cohort study suggests that peri-operative prescription NSAID use may be associated with continued opioid prescription claims at 90 and 180 days after knee arthroplasty, even after adjusting for other observed covariates for continuous opioid claims. These novel findings can inform clinical decision-making for post-surgical pain management, risk-benefit discussions with patients and future research.

Exacerbation of Pre-Existing Chronic Pain in Older Adults After SARS-CoV-2 Infection: A Single-Center, Cross-Sectional, Observational Study.

To identify the prevalence of exacerbation of pre-existing chronic pain after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and investigate the impact of exacerbated previous chronic pain on quality of life, sleep quality, anxiety and depression levels and risk factors associated with exacerbated chronic pain among elderly coronavirus disease of 2019 (COVID-19) survivors. In this cross-sectional study, elderly COVID-19 survivors with chronic pain residing in Continuing Care Retirement Community (CCRC) were recruited from April 2023 to June 2023. Eligible individuals were divided into exacerbation and non-exacerbation groups based on the patient-reported worsening symptoms of previous chronic pain after SARS-CoV-2 infection. Baseline information, COVID-19 symptoms, laboratory parameters, characteristics of exacerbated chronic pain, quality of life, anxiety and depression levels were systematically collected. Ninety-five (95/441, 21.5%) older adults suffered from exacerbated chronic pain with a median numerical rating scale (NRS) score of 6 (4-7) on a median duration of 4.9 (4.3-5.6) months after SARS-CoV-2 infection. More participants were not vaccinated against COVID-19 (46.5%, 40/86 vs 26.1%, 86/330, P < 0.001) in exacerbation group. Exacerbation group exhibited poor quality of life (EQ5D index: 0.734 [0.536-0.862] vs 0.837 [0.716-0.942], P < 0.001), more severe anxiety (GAD-7: 2 [0-5] vs 0 [0-3], P < 0.001) and depression (PHQ-9: 4 [2-7] vs 2.5 [0-5], P < 0.001) than non-exacerbation group. Risk factors significantly associated with exacerbation of pre-existing chronic pain were neuropathic pain (aOR 4.81, 95% CI 1.73-13.32, P = 0.003), lymphocyte count (aOR 0.31, 95% CI 0.12-0.78, P = 0.013) and D-dimer levels (aOR 6.46, 95% CI 1.92-21.74, P = 0.003). Our study observed a prevalence of 21.5% exacerbation of pre-existing chronic pain after SARS-CoV-2 infection, with a consequence of poor quality of life, more severe anxiety and depression. Previous chronic neuropathic pain, lower lymphocyte count and higher D-dimer levels were risk factors associated with the development of exacerbated previous chronic pain.

When biopsy goes wrong: a case series of misdiagnoses and complications from biopsies of masses of unknown origin potentially originating from a peripheral nerve.

Biopsies of peripheral nerve tumors (PNTs) are often used to plan an efficient treatment strategy. However, performing a biopsy is controversial when the mass is likely to be a benign PNT (BPNT). The aim of this study was to evaluate the side effects of biopsies in patients with potential PNTs. A retrospective and cross-sectional study was conducted on 24 patients who underwent biopsy of a mass of unknown origin potentially originating from a peripheral nerve (MUOPON), performed in nonspecialty services, and who were later referred to the authors' service for resection of their lesion between January 2005 and December 2022. The patients were evaluated for pain score, presence of a motor or sensory deficit, biopsy diagnosis, and definitive histopathological postsurgical diagnosis. The location of the tumor was supraclavicular in 7 (29.2%) patients, in the axillary region in 3 (12.5%), in the upper limb in 7 (29.2%), and in the lower limb in 7 (29.2%). Twenty-one (87.5%) patients were evaluated by MRI before biopsy, and 3 (12.5%) underwent ultrasound. One patient did not have an examination before the procedure. Based on the biopsy findings, 12 (50%) analyses had an inconclusive histopathological result. The preexisting pain worsened, as measured 1 week after biopsy, in all patients and had remained unchanged at the first evaluation by the authors (median 3 months, range 2-4 months). In 1 case, the open biopsy had to be interrupted because the patient experienced excruciating pain. Four (16.7%) patients developed motor deficits. Subsequent surgery was hampered by scar formation and intratumoral hemorrhage in 5 (20.8%) patients. The initial diagnosis obtained by biopsy differed from the final histopathological diagnosis in all patients, of whom 21 (87.5%) had BPNTs, 2 (8.3%) malignant peripheral nerve sheath tumors, and 1 (4.2%) an ancient schwannoma. Biopsies of PNTs are controversial and may result in misdiagnosis, neuropathic pain, or neurological deficit due to axonal damage, and they may also hinder microsurgical resection when if performed when not indicated. Indications for biopsy of an MUOPON must be carefully considered, especially if BPNT is a possible diagnosis.

A secondary analysis: the impact of pre-existing chronic pain among patients with cancer presenting to the emergency department with acute pain.

Patients with cancer may experience pain from cancer itself or its treatment. Additionally, chronic pain (CP) predating a patient's cancer diagnosis may make the etiology of pain less clear and the management of pain more complex. In this brief report, we investigated differences in biopsychosocial characteristics, pain severity, and opioid consumption, comparing groups of cancer patients with and without a history of CP who presented to the emergency department (ED) with a complaint of cancer-related pain. This secondary analysis of a prospective cohort study included patients with cancer who presented to the ED with a complaint of pain (≥ 4/10). Sociodemographic, clinical, psychological, and pain characteristics were assessed in the ED and subsequent hospitalization. Mann-Whitney U-, T-, and Chi-square tests were used to compare differences between patients with and without pre-existing CP before cancer. Patients with pre-existing CP had lower income (p = 0.21) and less formal education (p = 0.25) and were more likely to have a diagnosis of depression or substance use disorder (p < 0.01). Patients with pre-existing CP reported significantly greater pain severity in the ED and during hospitalization compared to those without pre-existing CP (p < 0.05), despite receiving greater amounts of opioid analgesics (p = 0.036). Identifying a history of pre-existing CP during intake may help identify patients with cancer with difficult to manage pain, who may particularly benefit from multimodal interventions and supportive care. In addition, referral of these patients for themanagement of co-occurring pain disorders may help decrease the usage of the ED for undertreated pain.

Trajectories of pain and opioid use up to one year after surgery: analysis of a European registry

BackgroundLong-term opioid use after surgery is a crucial healthcare problem in North America. Data from European hospitals are scarce and differentiation of chronic pain has rarely been considered. MethodsIn a mixed surgical cohort of the PAIN OUT registry, opioid use and chronic pain were evaluated before surgery, and 6 and 12 months after surgery (M6/M12). Subgroups with or without opioid medication and pre-existing chronic pain were analysed. M12-chronic pain was categorised as chronic postsurgical pain (CPSP) meeting the ICD-11 definition, chronic pain related to surgery not meeting the ICD-11 definition, and chronic pain unrelated to surgery. Primary endpoint was the rate of M12 opioid users. Variables associated with M12 opioid use and patient-reported outcomes were evaluated. ResultsOf 2326 patients, 5.5% were preoperative opioid users; 4.4% and 3.5% took opioids at M6 and M12 (P<0.001). Chronic pain before operation and at M6/M12 was reported by 41.2%, 41.8%, and 34.7% of patients, respectively (P<0.001). The rate of M12 opioid users was highest in group unrelated (22.3%; related 8.3%, CPSP 1.5%; P<0.001). New opioid users were 1.1% (unrelated 7.1%, related 2.3%, CPSP 0.7%; P<0.001). M12 opioid users reported more pain, pain-related physical and affective interference, and needed more opioids than non-users. The predominant variable associated with M12 opioids was preoperative opioid use (estimated odds ratio [95% confidence interval]: 28.3 [14.1−56.7], P<0.001). ConclusionsOpioid use was low in patients with CPSP, and more problematic in patients with chronic pain unrelated to surgery. A detailed assessment of chronic pain unrelated or related to surgery or CPSP is necessary. Clinical trial registrationNCT02083835.

Distal Clavicular Resection Worsens Outcomes in Rotator Cuff Repair: A National Database Study.

Distal clavicular resection (DCR) is a procedure used to alleviate acromioclavicular joint (ACJ) pain, often done alongside rotator cuff repair (RCR). This investigation explored the relationships between DCR and RCR, outcomes of DCR during RCR, and complication rates of DCR. This retrospective study used electronic medical record data from the TriNetX database. Cohorts were subdivided based on the timeline of DCR in comparison to RCR, as well as comparing RCR with DCR against RCR without DCR. In total 46 534 patients underwent RCR with 14.8% (6898) of these patients also undergoing DCR. And 72.8% (5021) had DCR during RCR, and 10.7% (740) had DCR after RCR. Less than 5% (<10) of patients with preexisting ACJ pain required DCR 3 years postoperatively, and 0.002% (78) patients without ACJ pain developed ACJ pain within 3 years. Less that 20 patients underwent DCR within 3 years of being diagnosed with ACJ pain. Patients who had RCR with DCR were more likely to have chronic pain postoperatively (P < .0001). Patients undergoing RCR do not require subsequent DCR. Performing DCR does not offer significant benefit when compared to performing isolated RCR without DCR in patients with preexisting ACJ pain, but increases risk for ACJ instability and chronic pain.