Pain-free Patients Research Articles

Pain profiles and variability in temporal summation of pain and conditioned pain modulation in pain-free individuals and patients with low back pain, osteoarthritis, and fibromyalgia.

Pain profiles (e.g. pro- and anti-nociceptive) can be developed using quantitative sensory testing (QST) but substantial variability exists. This study describes the variability in temporal summation of pain (TSP) and conditioned pain modulation (CPM) in chronic musculoskeletal pain patients, proposes cut-off values, and explores the association with clinical pain intensity. This is a secondary analysis in which TSP and CPM were assessed using cuff algometry in pain-free subjects (n = 69), and patients with chronic low back pain (cLBP, n = 267), osteoarthritis (n = 134), and fibromyalgia (n = 101). Using TSP and CPM from the pain-free subjects as a reference, four distinct pain profiles TSP (low/high) and CPM (low/high) were created, and differences in clinical pain between pain profiles were explored. Individual data revealed large inter-person variability. High TSP and low CPM were found in fibromyalgia (p < 0.01) and osteoarthritis (p < 0.01) but not cLBP when compared to pain-free subjects. The proportion of patients classified into the distinct pain profiles was significantly different (p < 0.001) with the largest proportion in the high TSP and low CPM group in fibromyalgia (52.5%) and osteoarthritis (41.4%). Clinical pain was not significantly different comparing the pain profiles, and no significant correlations were observed between clinical pain and TSP or CPM. These results demonstrated substantial inter-person variability in TSP and CPM in patients with different chronic pain conditions and pain-free subjects. The proportion of patients with a pro-nociceptive profile appears larger in fibromyalgia and osteoarthritis, but we found no association to clinical pain. This analysis shows that there is variability when assessing TSP and CPM in both pain-free subjects and patients with chronic pain. A cut-off for determining when a person is pain-sensitive is proposed, and data based on this cut-off approach suggest that significantly more patients with osteoarthritis and fibromyalgia are pain-sensitive (i.e. higher TSP and lower CPM) compared to pain-free subjects. This analysis does not find an association between pain sensitivity and clinical pain.

Impact of FOCUS-PDCA on reducing the incidence of complications after transradial intervention.

The aim of this study was to evaluate the effect of the find, organize, clarify, understand, select-plan, do, check, act (FOCUS-PDCA) procedure on reducing the incidence of complications at the puncture site. Patients who underwent the transradial interventional therapy (TRI) were divided into control (N.=160) and FOCUS-PDCA (N.=158) groups. The postoperative complications at the puncture site was observed in the two groups, and the pain, bleeding, swelling and comfort of the two groups were compared and analyzed. Two hours after surgery, the number of pain-free patients in the observation group was significantly higher than that in the control group (62.1% vs. 44.4%, P=0.014). The degree of swelling at 6 and 2 hours after TRI in observation group was significantly lower than that in control group (-0.08±0.23 vs. -0.00±0.17, P=0.001). No early radial artery occlusion was found in either group. The postoperative comfort score in observation group was significantly higher than that in control group (101.94±9.99 vs. 91.14±14.50, P<0.001). The FOCUS-PDCA approach may reduce the incidence of early pain and long-term swelling after TRI, improve patient comfort, and enhance the quality of specialist care. The results suggested that FOCUS-PDCA had the value of popularization and application.

Restrictive Strategy vs Usual Care for Cholecystectomy in Patients With Abdominal Pain and Gallstones

The 1-year results of the SECURE trial, a randomized trial comparing a restrictive strategy vs usual care for select patients with symptomatic cholelithiasis for cholecystectomy, resulted in a significantly lower operation rate after restrictive strategy. However, a restrictive strategy did not result in more pain-free patients at 1 year. To gauge pain level and determine the proportion of pain-free patients, operation rate, and biliary and surgical complications at the 5-year follow-up. This randomized clinical trial was a multicenter, parallel-arm, noninferiority, prospective study. Between February 2014 and April 2017, patients from 24 hospitals with symptomatic, uncomplicated cholelithiasis were included. Uncomplicated cholelithiasis was defined as gallstone disease without signs of complicated cholelithiasis, ie, biliary pancreatitis, cholangitis, common bile duct stones, or cholecystitis. Follow-up data for this analysis were collected by telephone from July 11, 2019, to September 23, 2023. Patients were randomized (1:1) to receive usual care or a restrictive strategy with stepwise selection for cholecystectomy. The primary, noninferiority end point was proportion of patients who were pain free as evaluated by Izbicki pain score at the 5-year follow-up. A 5% noninferiority margin was chosen. The secondary end points included cholecystectomy rates, biliary and surgical complications, and patient satisfaction. Among 1067 patients, the median (IQR) age was 49.0 years (38.0-59.0 years); 786 (73.7%) were female, and 281 (26.3%) were male. At the 5-year follow-up, 228 of 363 patients (62.8%) were pain free in the usual care group, compared with 216 of 353 patients (61.2%) in restrictive strategy group (difference, 1.6%; 1-sided 95% lower confidence limit, -7.6%; noninferiority P = .18). After cholecystectomy, 187 of 294 patients (63.6%) in the usual care group and 160 of 254 patients (63.0%) in the restrictive strategy group were pain free, respectively (P = .88). The restrictive care strategy was associated with 387 of 529 cholecystectomies (73.2%) compared with 437 of 536 in the usual care group (81.5%; 8.3% difference; P = .001). No differences between groups were observed in biliary and surgical complications or in patient satisfaction. In the long-term, a restrictive strategy results in a significant but small reduction in operation rate compared with usual care and is not associated with increased biliary and surgical complications. However, regardless of the strategy, only two-third of patients were pain free. Further criteria for selecting patients with uncomplicated cholelithiasis for cholecystectomy and rethinking laparoscopic cholecystectomy as treatment is needed to improve patient-reported outcomes. CCMO Identifier: NTR4022.

Metabolic Dysregulation and Its Role in Postoperative Pain among Knee Osteoarthritis Patients.

The inflammation observed in joint tissues is linked to pain caused by the production of proinflammatory cytokines. Since the biosynthesis of cytokines requires energy, their production is supported by extensive metabolic conversions of carbohydrates and fatty acids, which could lead to a disruption in cellular homeostasis. Therefore, this study aimed to investigate the association between POP development and disturbances in energy metabolic conversions, focusing on carbohydrate and fatty acid metabolism. Peripheral blood samples were collected from 26 healthy subjects and 50 patients with end-stage OA before joint replacement surgery. All implants were validated by orthopedic surgeons, and patients with OA demonstrated no inherent abnormalities to cause pain from other reasons than OA disease, such as malalignment, aseptic loosening, or excessive bleeding. Pain levels were assessed before surgery using the visual analogue scale (VAS) and neuropathic pain questionnaires, DN4 and PainDETECT. Functional activity was evaluated using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Three and six months after surgery, pain indices according to a VAS of 30 mm or higher were considered. Total RNA isolated from whole blood was analyzed using quantitative real-time RT-PCR (qRT-PCR) for the expression of genes related to carbohydrate and fatty acid metabolism. Protein levels of the examined genes were measured using an ELISA in the peripheral blood mononuclear cells (PBMCs). We used qRT-PCR because it is the most sensitive and reliable method for gene expression analysis, while an ELISA was used to confirm our qRT-PCR results. Among the study cohort, 17 patients who reported POP demonstrated significantly higher (p < 0.05) expressions of the genes PKM2, LDH, SDH, UCP2, CPT1A, and ACLY compared to pain-free patients with KOA. Receiver-operating characteristic (ROC) curve analyses confirmed the association between these gene expressions and pain development post-arthroplasty. A principle component analysis identified the prognostic values of ACLY, CPT1A, AMPK, SDHB, Caspase 3, and IL-1β gene expressions for POP development in the examined subjects. These findings suggest that the disturbances in energy metabolism, as observed in the PBMCs of patients with end-stage KOA before arthroplasty, may contribute to POP development. An understanding of these metabolic processes could provide insights into the pathogenesis of KOA. Additionally, our findings can be used in a clinical setting to predict POP development in end-stage patients with KOA before arthroplasty.

Continuum of somatosensory profiles in breast cancer survivors with and without pain, compared to healthy controls and patients with fibromyalgia.

The prevalence of persistent pain among breast cancer survivors (BCS) is high, and it is unclear what distinguishes those with persistent pain from those without. Research suggests that differences in somatosensory function evaluated by quantitative sensory testing (QST) may be responsible. This study aimed to describe somatosensory profiles in terms of hyper- and hypoesthesia in BCS with and without persistent pain using reference data from healthy controls. Second, QST parameters of BCS with and without pain were compared with those of healthy controls (i.e., a negative control group) and patients with fibromyalgia (i.e., a positive control group). Participants (n = 128) were divided into four equal groups: healthy controls, BCS with persistent pain, BCS without persistent pain, and patients with fibromyalgia. Nine QST parameters were evaluated at the trunk and at a remote location. Somatosensory profiles were determined by Z-score transformation of QST data using normative data from healthy controls. At the trunk, compared to healthy controls, BCS with persistent pain exhibited sensory aberrations across five out of seven QST parameters: pressure pain threshold, mechanical detection, and thermal thresholds. Pain-free BCS showed similar sensory aberrations across the four QST parameters compared to healthy controls: mechanical detection and thermal thresholds. Temporal summation and conditioned pain modulation were not significantly different between groups. BCS with persistent pain exert aberrations in peripheral processing of nociceptive signals, heightened facilitation of nociceptive signals, and higher psychosocial burden when compared to pain-free BCS, healthy controls, and patients with fibromyalgia. This study investigates the somatosensory function of breast cancer survivors with and without persistent pain using quantitative sensory testing and two control group (i.e., patients with fibromyalgia and healthy controls). Our results indicate somatosensory aberrations within the peripheral, but not central pathways in breast cancer survivors with persistent pain. Our findings contribute to a better understanding of the somatosensory mechanisms underlying persistent pain, which may inform future interventions to prevent the development of persistent pain, and improve treatment modalities.

Brain State Inference While under Anesthesia using CNN-Based Deep Learning Models

Anaesthesia is a critical procedure for surgeons because it allows them to operate on unconscious and pain-free patients. This paper proposes using CNN-based deep learning models to infer brain state while under anesthesia. Both neuroscience research and clinical situations can help determine how deeply unconscious a patient is during anesthesia. The electroencephalogram (EEG) is a real-time, objective method for detecting anesthetic-induced changes in brain states of arousal and/or cognition. To pre-process the signal, the adaptive median filter is used. The median filter is a signal-filtering method used to remove noise from signals. The feature extraction process is carried out using wavelet decomposition, which allows for perfect signal reconstruction. To classify anesthetized brain states, this paper employs a CNN-based technique.

Radiosurgery for classical trigeminal neuralgia: impact of the shot size on clinical outcome

BackgroundThis study compares the outcome of patients suffering from medically refractory classical trigeminal neuralgia (TN) after treatment with radiosurgery using two different shot sizes (5- and 6-mm).MethodsAll patients included in this open, prospective, non-controlled study were treated in a single institution for TN (95 cases in 93 patients) with LINear ACcelerators (LINAC) single-dose radiosurgery using a 5-mm shot (43 cases) or 6-mm shot (52 cases). The target was positioned on the intracisternal part of the trigeminal nerve.ResultsThe mean Dmax (D0.035) to the brainstem was higher in the 6-mm group: 12.6 vs 21.3 Gy (p < 0.001). Pain relief was significantly better in the 6-mm group: at 12 and 24 months in the 6-mm group the rate of pain-free patients was 90.2 and 87.8%, respectively vs. 73.6 and 73.6% in the 5-mm group (p = 0.045). At 12 and 24 months post-radiosurgical hypoesthesia was more frequent in the 6-mm group: 47.0 and 58% vs.11.3 and 30.8% in the 5-mm group (p = 0.002). To investigate the effect of cone diameter and the dose to the brainstem on outcomes, patients were stratified into three groups: group 1 = 5-mm shot, (all Dmax < 25 Gy, 43 cases), group 2 = 6-mm shot, Dmax < 25 Gy (32 cases), group 3 = 6-mm shot Dmax > 25 Gy (20 cases). At 12 months the rates of hypoesthesia were 11.3, 33.5 and 76.0%, respectively in groups 1, 2 and 3 (p < 0.001) and the rates of recurrence of pain were 26.4, 16.5 and 5%, respectively, (p = 0.11).ConclusionLINAC treatment with a 6-mm shot provided excellent control of pain, but increased the rate of trigeminal nerve dysfunction, especially when the maximum dose to the brainstem was higher than 25 Gy.

Corticomotor excitability is altered in central neuropathic pain compared with non-neuropathic pain or pain-free patients

ObjectivesCentral neuropathic pain (CNP) is associated with altered corticomotor excitability (CE), which can potentially provide insights into its mechanisms. The objective of this study is to describe the CE changes that are specifically related to CNP. MethodsWe evaluated CNP associated with brain injury after stroke or spinal cord injury (SCI) due to neuromyelitis optica through a battery of CE measurements and comprehensive pain, neurological, functional, and quality of life assessments. CNP was compared to two groups of patients with the same disease: i. with non-neuropathic pain and ii. without chronic pain, matched by sex and lesion location. ResultsWe included 163 patients (stroke=93; SCI=70: 74 had CNP, 43 had non-neuropathic pain, and 46 were pain-free). Stroke patients with CNP had lower motor evoked potential (MEP) in both affected and unaffected hemispheres compared to non- neuropathic pain and no-pain patients. Patients with CNP had lower amplitudes of MEPs (366 μV ±464 μV) than non-neuropathic (478 ±489) and no-pain (765 μV ± 880 μV) patients, p < 0.001. Short-interval intracortical inhibition (SICI) was defective (less inhibited) in patients with CNP (2.6±11.6) compared to no-pain (0.8±0.7), p = 0.021. MEPs negatively correlated with mechanical and cold-induced allodynia. Furthermore, classifying patients' results according to normative data revealed that at least 75% of patients had abnormalities in some CE parameters and confirmed MEP findings based on group analyses. DiscussionCNP is associated with decreased MEPs and SICI compared to non-neuropathic pain and no-pain patients. Corticomotor excitability changes may be helpful as neurophysiological markers of the development and persistence of pain after CNS injury, as they are likely to provide insights into global CE plasticity changes occurring after CNS lesions associated with CNP.

Natural history, clinical characteristics, outcomes, and long-term follow-up of pain-free chronic pancreatitis.

Chronic pancreatitis (CP) is characterized by chronic abdominal pain and functional insufficiency. However, a small subset of patients with prior acute pancreatitis (AP) and/or underlying risk factors for developing CP may be pain-free at diagnosis and may have a different clinical course. We aimed to compare the clinical characteristics, outcomes, and healthcare utilization between CP patients with and without pain. Reviewed patients with established CP were followed in our Pancreas Center between January 2016 and April 2021. Patients without risk factors for developing CP and/or without AP prior to their diagnosis and only with incidental radiologic features of CP were excluded, so as to minimize confounding factors of pancreatopathy unrelated to CP. Patients were divided into painful and pain-free groups to analyze differences in demographics, outcomes, and healthcare utilization. Of 368 CP patients, 49 (13.3%) were pain-free at diagnosis and had remained so for >9 years. There were no significant differences in body mass index, race, sex, or co-morbidities between the two groups. Pain-free patients were older at diagnosis (53.9 vs 45.7, P = 0.004) and had less recurrent AP (RAP) (43.8% vs 72.5%, P < 0.001) and less exocrine pancreatic insufficiency (EPI) (34.7% vs 65.7%, P < 0.001). Pain-free patients had less disability (2.2% vs 22.0%, P = 0.003), mental illness (20.4% vs 61.0%, P < 0.001), surgery (0.0% vs 15.0%, P = 0.059), and therapeutic interventions (0.0% vs 16.4%, P = 0.005) for pain. We described a unique subset of patients with underlying risk factors for CP and/or prior AP who were pain-free at diagnosis. They were older at diagnosis, had less EPI and RAP, and overall favorable outcomes with minimal resource utilization.

Neuromuscular Toxicity and Dose-Volume Relationships Following SBRT for Bone Oligometastases: Post-Hoc Analysis of Two Ongoing Clinical Trials

<h3>Purpose/Objective(s)</h3> Growing evidence suggests that stereotactic body radiotherapy (SBRT) is effective for oligometastatic disease. Currently, there is limited data to define dose-volume relationships between muscle and adipose tissues and neuromuscular toxicities. In this post hoc analysis, we evaluated these associations in patients enrolled in two phase II clinical trials (NCT03575611, NCT03599765) where bone oligometastases were ablated with SBRT. <h3>Materials/Methods</h3> We reviewed three-fraction SBRT treatment plans for bone oligometastases where total dose ranged from 24-36 Gy. We contoured muscle and adjacent soft tissue receiving at least 10Gy based on anatomical function (e.g., hip flexors) and defined the largest-volume group as the most-affected functional muscle group (MFMG). Muscle and adipose tissues within MFMGs (MFMG-m and MFMG-a respectively) were further delineated by semi-automated contouring scripts using previously validated CT Hounsfield unit ranges for muscle (-29 to +150 HU) and adipose (-190 to -30 HU). Associations between neuromuscular adverse events (AE) (graded by Common Terminology Criteria for Adverse Events version 5) with dose to 2cc-30cc of contoured volumes (D2cc-D30cc) and clinical variables (BMI, ECOG, etc.) were assessed using two-sided Mann-Whitney U tests. Results were considered significant at P<0.0071 with Bonferroni correction. <h3>Results</h3> We evaluated 43 treatment plans for 37 patients with target lesions in the pelvic girdle (n=18), rib (n=15), femur (n=4), lumbar vertebra (n=2), scapula (n=2), and sternum (n=2). Three patients (8.1%) experienced grade 3 hip pain, 1 patient (2.7%) had grade 2 hip pain, and 2 patients (5.4%) had grade 1 hip or rib pain. There were no grade 4 or 5 AEs. Median time to AE was 2.3 months (range: 1.2–4.5 months). Patients with AEs had significantly higher MFMG D25cc (median = 28.4 vs 18.6Gy; p=0.004), MFMG-m D25cc (median = 27.7 vs 17.3Gy; p=0.006), and MFMG-a D5cc (median = 30.2 vs 18.9Gy; p=0.006) compared to pain-free patients. We identified a dose/volume threshold at MFMG D25cc > 25 Gy, where 5/11 (45.5%) treatment plans above and 1/32 (3.1%) below this threshold led to AEs, corresponding to an odds ratio of 25.8. There was no relationship between AEs and BMI, ECOG score, or demographics. No local tumor recurrences occurred with median follow-up of 15.5 months (range: 3.1–35.4 months). Two patients with grade 3 AEs after SBRT to pelvic girdle lesions had 3- and 5-month follow-up MRIs which identified soft tissue edema consistent with our findings. <h3>Conclusion</h3> Preliminary results from two prospective trials suggests that SBRT for bone oligometastases can be conducted safely with excellent tumor control and minimal toxicity. We propose that MFMG D25cc be limited to 25 Gy to avoid symptomatic neuromuscular toxicity. Future studies are needed for dose criteria verification.

Effects of High Cervical Spinal Cord Stimulation on Gait Disturbance and Dysarthropneumophonia in Parkinson's Disease and Parkinson Variant of Multiple System Atrophy: A Case Series.

High cervical spinal cord stimulation (HCSCS) was found to have therapeutic effects on Parkinsonian gait disturbance. However, the results were inconsistent and confounded with symptoms of pain. This study aimed to reveal the gait and dysarthric effects of HCSCS in PD (Parkinson’s disease) and MSA-P (Parkinson variant of multiple system atrophy) patients without pain. Three PD and five MSA-P patients without painful comorbidities were assessed for gait performance and speech before SCS surgery and at 3- and 6-month follow-up. Stride length and the time spent in the Timed Up-and-Go task showed little change after HCSCS surgery. Overall voice quality (measured by dysphonia severity index) and perceptual speech intelligence improved significantly at 3 months, but improvements slightly diminished at 6 months postoperatively. Change in quality of life (measured by 8-item Parkinson’s disease questionnaire) was also notable at 3 months but narrowed over time following HCSCS. In conclusion, HCSCS showed therapeutic effects in improving the dysarthria but not gait disturbance in pain-free PD and MSA-P patients.

Mirror peripheral neuropathy and unilateral chronic neuropathic pain: insights from asymmetric neurological patterns in leprosy.

Leprosy-related multiple mononeuropathy offers a pattern of impairment where neuropathy with and without neuropathic pain (NeP) are present in the same individual, thus allowing to investigate peripheral sensory and innervation in both conditions. This cross-sectional study collected data on clinical and neurological examination, pain assessment questionnaires, quantitative sensory test, and intraepidermal nerve fiber density of patients with leprosy and divided the cohort into 2 groups: with NeP (P+) and without NeP (P-). Furthermore, we assessed mirror body areas in the same NeP individuals with bilateral neuropathy also presenting unilateral NeP. Pain-free patients having unilateral neuropathy were controls. A total of 37 P+ and 22 P- patients were evaluated. Limb areas with NeP had signs of C-fiber dysfunction and hyperesthesia on quantitative sensory testing compared with limb areas having neuropathy without NeP. Skin denervation was found in all patients with leprosy. Comparisons of limbs with and without neuropathy and with and without NeP revealed that higher heat pain thresholds (HPTs) were associated with neuropathic pain areas, whereas less altered HPT was correlated with higher fiber density. Furthermore, a relationship was found between time of leprosy treatment termination and more intense neuropathy, expressed by HPT increasing 0.03°C each month. As expected, interindividual comparisons failed to show differences in intraepidermal nerve fiber density and subepidermal plexus areas between P+ and P- patients ( P = 0.2980, P = 0.9044; respectively). Higher HPT and lower mechanical detection threshold were related to NeP. This study pointed out the relevance of intraindividual comparisons including mirror areas when assessing local changes in peripheral NeP.

Moderate sedation with single-dose remimazolam tosilate in elderly male patients undergoing transurethral resection of the prostate with spinal anesthesia: a prospective, single-arm, single-centre clinical trial

BackgroundRemimazolam tosilate (RT) is a newly listed benzodiazepine for sedation and anesthesia featuring quick onset of effects, short maintenance and recovery times, which is currently under research. This trial was conducted to determine the median effective dose (ED50) and the 95% effective dose (ED95) of single-dose remimazolam for moderate sedation in elderly patients undergoing transurethral resection of the prostate (TURP) under spinal anesthesia, and to evaluate its efficacy and safety.MethodsThirty male patients aged 65–80 years old were recruited for selective TURP. Remimazolam was administered intravenously to pain-free patients (VAS score < 1) within 1 min of successful spinal anesthesia by the same anesthesiologist. We used modified Dixon’s up-and-down sequential allocation method to determine the ED50 and ED95 of the agent with an initial dosage of 0.1 mg/kg. Successful sedation was defined as an MOAA/S score ≤ 3 and above 1. A score of > 3 was deemed as failed sedation. Recruitment continued until ten independent pairs (from successful sedation to failed sedation) would give a reliable estimation of the ED50 and ED95 of RT and their 95% confidence intervals.ResultsThe ED50 of remimazolam was 0.063 (95% C.I. 0.045–0.073) mg/kg. Its ED95 was 0.079 (95% C.I. 0.07–0.137) mg/kg. Remimazolam was safe in its application.ConclusionsA single-dose of RT proves to be safe for assisted sedation during TURP in elderly male patients under spinal anesthesia with a lower incidence of adverse events. Its ED50 and ED95 were 0.063 mg/kg and 0.079 mg/kg, respectively.Trial registrationhttp://www.chictr.org.cn (ChiCTR2100051912).

Propofol ve Rokuronyum Enjeksiyon Ağrısı İçin Vibrasyon Anestezisi

ABSTRACT Objective: Despite numerous strategies for preventing or alleviating pain associated with propofol and rocuronium injections, it remains common and distressing for patients. Application of vibration is an effective method of reducing pain during facial cosmetic injections and some venipuncture procedures. But it has been studied in limited trials for the context of propofol or rocuronium injection pain. This randomized study aims to evaluate the effect of vibration anesthesia on the incidence and severity of propofol and rocuronium injection pain. Methods: Fifty-one patients who underwent elective gynecologic operations under general anesthesia, were randomized, into two groups. On the dorsal side of the hand, a 20 G intravenous cannula was inserted. In Group V (n=25), propofol and rocuronium was administered following 1 minute of pre-treatment with the vibration device on the intravenous catheter trace. In Group C (n=26) vibration was not applied before drug administration. Propofol pain was recorded according to McCrirrick and Hunter scale and rocuronium injection pain response was evaluated with a four-point scale. Results: The number of patients who experienced propofol injection pain, in the vibration group was significantly lower than in the control group (p=0.007). The percentage of pain free patients in Group V was 88%, whereas 46% in Group C. The incidence of withdrawal movements associated with rocuronium injection pain was also significantly lower in Group V (p=0.043). Percentage of pain free patients in Group V was 28% whereas 3.8% in Group C. Conclusion: Vibration anesthesia before propofol and rocuronium injection significantly reduced the injection pain. Keywords: Injection pain, propofol, rocuronium, vibration

Prevalence and determinants of pain in chronic inflammatory demyelinating polyneuropathy: Results from the German INHIBIT registry.

Pain, fatigue and depression in chronic inflammatory demyelinating polyneuropathy (CIDP) are often underestimated, as the focus lies on sensorimotor dysfunction and gait instability. The aim of this study was to investigate their prevalence, characteristics and contribution to disability in a prospective cohort of 84 patients with CIDP. Pain, fatigue, depression and quality of life were measured using the Pain Detect Questionnaire, Krupp's Fatigue Severity Scale, Beck Depression Inventory II and the German Short-Form 36 Health Survey. Sensorimotor deficits and disability were assessed using the Inflammatory Neuropathy Cause and Treatment overall disability score, the Rasch-built Overall Disability Scale, the Medical Research Council sum score and the Inflammatory Neuropathy Cause and Treatment sensory sum score. The interrelation between the five factors was assessed using analysis of variance and linear regression analysis. Pain was reported in 62%, mostly of moderate and severe intensity, whereas pain characteristics indicated neuropathic pain (NP) in 29%. Sensory dysfunction was stronger in NP patients compared to pain-free patients (p=0.001). Pain of any type, especially NP, was associated with more pronounced fatigue symptoms (p=0.010). Depressive symptoms were more frequent in patients with pain compared to the pain-free patients (61% vs. 33%, p=0.02) and were more severe and frequent in NP than in non-NP patients (p=0.005). Patients with pain had a worse physical quality of life than pain-free patients (p=0.001). Pain, depression and fatigue are relevant disability factors in CIDP affecting quality of life. Sensory dysfunction is associated with NP. Therefore, evaluation of CIDP-related disability should include pain and sensory function for adequate monitoring of therapeutic interventions.

Physical Function in Amateur Athletes with Lumbar Disc Herniation and Chronic Low Back Pain: A Case-Control Study.

This study aimed to analyze if chronic low back pain (LBP) and lumbar disc herniation induce biomechanics, flexibility, body balance, physical activity, and muscular function alterations compared to a similar asymptomatic cohort. Fifty male volunteers (n = 25 with chronic LBP and lumbar disc herniation and n = 25 pain-free subjects) were enrolled. Range of motion (internal and external hip rotation, ankle dorsiflexion, and active straight leg raise, ASLR), trunk flexibility (finger–floor distance), body balance (Y-balance test) and muscle function (Biering–Sorensen test, prone and lateral bridges) outcomes were assessed. Comparative analyses between sides and group were conducted. Results: Patients showed greater weight and BMI compared with controls (p < 0.05). None of the outcomes bilaterally assessed showed side-to-side differences for pain-free participants (all, p > 0.05) or LBP patients (all, p > 0.05). Regarding the differences between groups, LBP patients showed limited internal hip rotation (p < 0.001), finger–floor distance (p < 0.001), body balance (p < 0.001), and muscle endurance (planks p < 0.001; Biering–Sorensen test p < 0.05). External hip rotation, ASLR, and ankle dorsiflexion range of movement were comparable in both groups (p > 0.05). The sample of pain-free amateur athletes showed greater range of movement for internal hip rotation, lower finger–floor distance, better body balance, and muscle function. However, the external hip rotation, ankle dorsiflexion, and ASLR tests showed no difference between cases and controls.

Exploring alterations in sensory pathways in migraine

BackgroundMigraine is a neurological disorder characterized by intense, debilitating headaches, often coupled with nausea, vomiting and sensitivity to light and sound. Whilst changes in sensory processes during a migraine attack have been well-described, there is growing evidence that even between migraine attacks, sensory abilities are disrupted in migraine. Brain imaging studies have investigated altered coupling between areas of the descending pain modulatory pathway but coupling between somatosensory processing regions between migraine attacks has not been properly studied. The aim of this study was to determine if ongoing functional connectivity between visual, auditory, olfactory, gustatory and somatosensory cortices are altered during the interictal phase of migraine.MethodsTo explore the neural mechanisms underpinning interictal changes in sensory processing, we used functional magnetic resonance imaging to compare resting brain activity patterns and connectivity in migraineurs between migraine attacks (n = 32) and in healthy controls (n = 71). Significant differences between groups were determined using two-sample random effects procedures (p < 0.05, corrected for multiple comparisons, minimum cluster size 10 contiguous voxels, age and gender included as nuisance variables).ResultsIn the migraine group, increases in infra-slow oscillatory activity were detected in the right primary visual cortex (V1), secondary visual cortex (V2) and third visual complex (V3), and left V3. In addition, resting connectivity analysis revealed that migraineurs displayed significantly enhanced connectivity between V1 and V2 with other sensory cortices including the auditory, gustatory, motor and somatosensory cortices.ConclusionsThese data provide evidence for a dysfunctional sensory network in pain-free migraine patients which may be underlying altered sensory processing between migraine attacks.

Analgesic Efficacy of Ibuprofen and Diclofenac Potassium on Postoperative Endodontic Pain in Maxillary and Mandibular First Molars with Irreversible Pulpitis: A Randomised Controlled Trial.

The management of postoperative endodontic pain (PEP) is essential to contemporary endodontic practice. Diclofenac and ibuprofen (IBU) are two of the most widely-used non-steroidal anti-inflammatory analgesics. However, their comparative data are neither sufficient nor conclusive. This prospective randomised clinical trial aimed to compare the analgesic efficacy of diclofenac potassium (DFK) with IBU on PEP in maxillary and mandibular first molars diagnosed with irreversible pulpitis after single-visit non-surgical root canal treatment. Sixty-four patients were randomised into two groups of DFK (n=32) and IBU (n=32), using the stratified permuted randomisation method, and 61 participants completed the trial. After root canal treatment, patients randomly received IBU 400 mg every 6 hours (n=31) or DFK 50 mg every 8 hours (n=30) for 24 hours. Patients recorded their pain level on 0-100 mm visual analogue scales (VAS) at 2, 4, 6, 12, and 24 hours after the treatment. Recorded VAS scores and the number of pain-free patients (VAS<5) were compared between the two groups. A generalised linear estimation equation model, Chi-Square test, and Mann-Whitney U test were used to analyse the data. The mean overall PEP score was statistically significantly lower in the DFK group than the IBU group with a p value of 0.030. Pain scores at 2 (p=0.034), 4 (p=0.021), and 24 hours (p=0.042) after the treatment were also significantly lower for DFK than IBU. The number of pain-free patients was also significantly higher in the DFK group at 2-hour (p=0.015) and 4-hour (p=0.048) time points and overall (p=0.013) compared to the IBU group. There was no adverse effect observed in either group. Based on the results, taking multi-dose DFK 50 mg by the clock had better analgesic outcomes than multi-dose IBU 400 mg for PEP management. (EEJ-2022-01-07).

Microvascular decompression for trigeminal neuralgia, long-term follow-up results and assessment of possible prognostic factors: a single-center retrospective cross-sectional cohort study

Aim: Prognostic factors detection and analysis of long-term results of microvascular decompression for trigeminal neuralgia. Materials and methods. 161 cases of trigeminal neuralgia (TN) treatment by MVD technique without preliminary invasive interventions within 10 years were analyzed. Two blocks of information were designed which included objective case data (8 factors) and patient satisfaction survey (5 questions). Follow-up minimal cut-off was 1 year (median 5.8 years). The primary end point is the proportion of pain free patients and BNI (Barrow Neurological Institute) score at last follow-up. The secondary end point is the assessment of possible risk factors of treatment failure: symptoms duration, decompression type, affected nerve branches, neurovascular conflict visible on MRI, different indications for surgery. Logit-regression analysis was carried out. Significance level was set at p&lt;0,01. Results. Among the studied factors as predictors for pain recurrence all but one failed to reach significance threshold. Conflict on MRI (p=0,231), involved nerve branches (p=0,340), indications for surgery (p=0,659), number of involved vessels (p=0,834), achieved decompression type (p=0,157), venous compression (p=0,143), gender (p=0,150), affected side (p=0,934) did not reach the significance level. For symptoms duration p=0,0012. Conclusions. As a result of multifactorial analysis of study results, the only significant prognostic factor for treatment failure (pain recurrence or worsening of obtained result) was symptoms duration at the time of surgery.

Adductor canal block performed 20 hours after total knee arthroplasty to improve postoperative analgesia and functional recovery: a double-blind randomized controlled clinical trial.

The goal of postoperative pain protocols in total knee arthroplasty (TKA) is to get pain free patients throughout severe pain period without impairing walking ability. The aim of the study was to investigate if an adductor canal block performed 20 hours after TKA, in patients treated with systemic analgesia and intraoperative local infiltration anesthesia (LIA), improves postoperative pain and functional outcomes. A prospective randomized, double-blinded controlled study was conducted. One hundred eighty-three patients undergoing primary TKA were randomized to receive either a sham block or an adductor canal block with 20 mL of ropivacaine 0.5%. The primary outcome was resting and dynamic pain scores using the Numerical Pain Rating Scale (NPRS). Secondary outcomes included opioid rescue requirements, quadriceps and adductor muscle strength, patient ability for ambulation and complications. Two hours after the block, in adductor canal block group NPRS was significantly lower at rest (1 [0-2] vs. 3 [2-5], P<0.001) and with mobilization (5 [3-6] vs. 6 [5-8], P<0.001), and quadriceps strength was significantly higher (3.7 [2.7-6] vs. 3 (1.7-4.9), P=0.023). The differences were not maintained beyond 24 hours post-block. In the first 24 hours the percentage of patients with tramadol requirements was lower in the adductor canal block group (36 [38.3] vs. 52 [58.4], P=0.006). Other secondary outcomes were similar between groups. There were no patient falls. An adductor canal block done 20 hours after total knee arthroplasty reduces pain and opioid requirements without increasing the risk of falls. An optimal pain control, especially at movement was not achieved.