Search Results (341)

Background/Objectives: Blood Flow Restriction training has been suggested as a method to enhance strength and neuromuscular adaptations at low exercise intensities. Early reports indicate potential effects on pain perception, myofascial stiffness, and flexibility; however, the evidence remains inconsistent. Method: Twenty-two healthy adults participated in a randomized, within-participant, contralateral-controlled design, performing 5 min of treadmill walking (4–5 km/h) with and without blood flow restriction at 70% arterial occlusion pressure. Pressure pain threshold, hip range of motion, and hamstring stiffness were measured before and after the intervention. Adverse effects were recorded. Results: Changes in pain threshold, range of motion, and myofascial stiffness were similar between conditions. The pressure pain threshold decreased slightly in both conditions, regardless of BFR, while range of motion and stiffness remained unchanged. Mild, short-lasting sensations (cuff pressure, erythema, tingling) were reported, with no adverse events. Conclusions: A single short session of low-intensity BFR walking did not change pain sensitivity, flexibility, or myofascial stiffness in healthy adults. The protocol was well tolerated. Repeated or longer interventions may be needed to see measurable effects. Full article

Background/Objectives: Quadriceps arthrogenic muscle inhibition (AMI) represents a key impairment following anterior cruciate ligament reconstruction (ACLR), contributing to quadriceps weakness. Although transcutaneous electrical nerve stimulation (TENS) and percutaneous electrical nerve stimulation (PENS) have been primarily investigated for analgesia, their effects on quadriceps strength in the early postoperative period remain underexplored. Methods: This study describes a single-blinded, parallel-group randomized controlled trial investigating the short-term effects of a single high-frequency TENS session and a novel long-term potentiation (LTP) PENS protocol on quadriceps strength and related clinical outcomes after ACLR. Fifty-four participants will be randomly allocated using block randomization in a 1:1:1 ratio to one of three groups: a control group (conventional post-ACLR rehabilitation only), a TENS group (conventional rehabilitation plus a single high-frequency TENS session), or a PENS group (conventional rehabilitation plus a single LTP PENS session). Participants will receive neuromodulatory intervention during the sixth postoperative week. The LTP PENS protocol consists of five 5 s stimulation bursts at 100 Hz and 250 μs pulse width and has only been investigated once in patients with upper limb pathology, underscoring its novelty in a postoperative setting. Results: The primary outcome is quadriceps maximal voluntary isometric contraction, selected as a clinically relevant surrogate of quadriceps activation deficits associated with AMI. Secondary outcomes include pain intensity, pressure pain threshold, knee range of motion, thigh muscle perimeter, knee effusion and swelling, and self-reported function and knee-related quality of life. Outcomes will be assessed at baseline, immediately post-treatment, and 1 and 7 days post-intervention by a blinded assessor. Full article

Background: Chronic nonspecific neck pain (CNNP) is a widespread musculoskeletal condition affecting individuals across all age groups. Although cervical stabilization exercises (CSE) and Thai self-massage have each demonstrated therapeutic potential, evidence regarding the effectiveness of the combined applications of CSE and Thai self-massage remains limited. This study aimed to investigate the effects of a combined program of CSE and Thai self-massage (CSTM) on pain intensity (PI), pressure pain threshold (PPT), and neck disability (ND) in young adults with CNNP. Methods: This single-blind randomized controlled trial was conducted at the Department of Physical Therapy, School of Integrative Medicine, Mae Fah Luang University, Thailand. Fifty young adults with CNNP were randomly assigned into two groups. The CSTM group performed CSE integrated with Thai self-massage, whereas the control group practiced stretching exercises exclusively. Both groups engaged in their respective programs three times per week for a duration of four weeks. PI, PPT, and ND were assessed at baseline, after four weeks (Week 4), and at a two-week follow-up (Week 6). Results: Both groups showed significant improvements in PI, PPT, and ND (p < 0.05), representing within-group comparisons, at Week 4 and Week 6. Furthermore, between-group comparisons at Week 4 and Week 6 indicated that the CSTM group achieved significantly greater improvements in PI and ND than the control group (p < 0.05). Conclusion: A four-week program combining CSE with Thai self-massage was effective in reducing pain intensity and neck disability in young adults with CNNP, with benefits maintained at short-term follow-up. Trial registration: Thai Clinical Trials Registry (TCTR20231102008), registered on 2 November 2023. Full article

Background: Craniocervical pain and temporomandibular disorders (TMDs) are prevalent, interconnected conditions. While Movement Representation Techniques (MRTs) are cognitive interventions targeting central pain mechanisms, their specific efficacy here lacks synthesis. This study systematically analyzes the effectiveness of MRTs, such as motor imagery (MI) and action observation (AO), on pain and function in individuals with craniocervical and orofacial pain. Methods: A systematic review of RCTs (PROSPERO: CRD420251155428) was conducted following PRISMA guidelines. Four databases were searched for studies applying MRTs (MI, AO, laterality discrimination) to adults with craniocervical or orofacial pain. Primary outcomes were pain and functionality. Methodological quality was assessed using the PEDro scale and Cochrane RoB 2 tool. Results: Eight RCTs (n = 362) were included. Methodological quality was high (PEDro scores 8–9). MRTs significantly increased Pressure Pain Threshold (PPT) in the masseter, trapezius, and cervical regions. Functional improvements included enhanced cervical range of motion and sensorimotor control. AO consistently demonstrated superior outcomes. However, results for orofacial variables were derived from asymptomatic subjects. Results for cervical muscle strength were inconsistent. Conclusions: MRTs, especially AO, show potential to reduce pain and improve function in craniocervical disorders. Evidence in symptomatic orofacial pain populations is non-existent. Protocol heterogeneity and limited research groups necessitate further high-quality, multicenter RCTs to establish robust clinical guidelines. Full article

Background and Clinical Significance: Tramadol-associated acute angle-closure crisis is rare and has been reported only once previously following subcutaneous administration. Acute angle closure may occur in anatomically predisposed individuals in the setting of perioperative physiological stress, with medications acting as contributory factors. Case Presentation: A 38-year-old woman developed a bilateral acute angle-closure crisis shortly after initiating oral tramadol for postoperative pain relief following an uncomplicated robotic-assisted laparoscopic hysterectomy. Within 24 h, she experienced headache, nausea, vomiting, periocular pain, and blurred vision. Ophthalmic examination revealed markedly elevated intraocular pressure (45 mmHg OD, 39 mmHg OS), corneal epithelial edema, mid-dilated pupils, and completely closed angles on gonioscopy. Prompt intraocular pressure–lowering therapy followed by bilateral Nd:YAG laser peripheral iridotomy resulted in full anatomical and functional recovery, with visual acuity returning to baseline within 48 h. Conclusions: In this case, extreme anatomical susceptibility due to significant hyperopia and very short axial lengths likely played a dominant role, with perioperative physiological factors contributing to pupillary dilation. Oral tramadol may have acted as a permissive factor lowering the threshold for angle closure rather than as a sole causative agent. Awareness of this potential association is important to facilitate early ophthalmic referral and prevent unnecessary diagnostic evaluations. Full article

Objectives: To estimate the preliminary effects of adding percutaneous electrical nerve stimulation (PENS) to a pain education and exercise program on pain sensitization, function, and psychological factors in patients with knee osteoarthritis (KOA), compared with adding a control transcutaneous electrical nerve stimulation (TENS) intervention or sham PENS. Feasibility, safety, and the success of participant blinding were also evaluated. Methods: Thirty patients with KOA were randomly assigned to one of three intervention groups: PENS, control TENS, or sham PENS. All interventions were delivered in addition to a program comprising four pain education sessions and a structured 12-week exercise plan. Primary outcomes included the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Visual Analogue Scale (VAS), Chronic Pain Grading Scale (CPGS), Pressure Pain Threshold (PPT), Conditioned Pain Modulation (CPM), and Temporal Summation of Pain (TSP). Psychological variables were assessed as secondary outcomes. Feasibility outcomes included recruitment and retention rates, adherence, adverse events, and blinding success. Results: Significant and consistent improvements over time were observed across the full sample for VAS (Chi² = 13.38; p = 0.004), CPGS (Chi² = 15.22; p = 0.002), WOMAC (Chi² = 31.44; p < 0.001), CPM (Chi² = 8.77; p = 0.032) and TSP (Chi² = 53.11; p < 0.001) with changes in potential clinical relevance at the within-group level. However, no statistically significant group–time interactions were found for any variable, suggesting no clear differential effects between interventions. Feasibility outcomes were favorable, with high retention and adherence, a low incidence of mild adverse events, and generally adequate participant blinding. Conclusions: Within the limits of this small exploratory trial, adding PENS to a pain education and exercise program did not appear to provide additional benefits in pain sensitization, function, or psychological factors beyond those achieved with the multimodal program and sham or control electrical stimulation. Feasibility, safety, and blinding outcomes support the viability of conducting a larger definitive trial. Full article

Introduction: Temporomandibular disorders (TMDs), neck pain (NP), and cervicogenic headache (CGH) frequently co-occur. We aimed to assess TMD prevalence and orofacial clinical features in adults with NP or CGH versus asymptomatic controls. Methods: We searched PubMed, CINAHL, Web of Science, and Scopus from inception to 31 July 2025. Eligible designs were analytical cross-sectional studies comparing TMD prevalence, signs, or symptoms between NP/CGH patients and controls. Outcomes included TMD prevalence, jaw mobility, masticatory muscle pressure pain thresholds (PPT), and palpation findings. Risk of bias was appraised with the JBI analytical cross-sectional checklist. Random-effects meta-analyses synthesized odds ratios (ORs) for dichotomous and mean/standardized mean differences (MDs/SMDs) for continuous outcomes; heterogeneity was quantified with I² (and τ² where available). Small-study effects were inspected visually (k < 10). Certainty of evidence was assessed with GRADE. Results: From 4130 records, nine studies met the criteria (eight NP, 400 subjects; one CGH, 44 subjects). NP was associated with higher TMD prevalence versus controls (OR 3.64, 95% CI 1.35–9.84; I² = 13%). Jaw mobility was reduced in either pain-free opening (one study), unassisted opening (one study), or maximum assisted opening (three studies; MD −6.16 mm, 95% CI −10.05; −2.28; I² = 83%). PPTs were lower in symptomatic groups for masseter (SMD −1.11, 95% CI −1.89 to −0.32; three studies; I² = 92.6%) and temporalis (SMD −0.77, 95% CI −1.04 to −0.50; five studies; I² = 69%). Myofascial trigger points and pain on palpation of masticatory muscles or TMJ were more frequent in experimental groups. Discussion: The findings suggest consistent associations between NP/CGH and TMD prevalence with signs of orofacial dysfunctions. Certainty of evidence was very low due to the cross-sectional design, incomplete confounding control, and moderate heterogeneity for several outcomes. Conclusions: Adults with NP/CGH show higher TMD prevalence and reduced jaw mobility with lower masticatory PPTs. The results support integrated assessment, and prospective longitudinal studies are needed. Full article

Introduction: Migraine is featured by altered nociceptive processing and the presence of cognitive impairments. No study has previously investigated the influence of neurocognitive performance and executive functions in descending pain processing in this population. Aim: To assess the influence of neurocognitive processes and executive functions in conditioned pain modulation (CPM) activation in women with migraine. Methods: A cross-sectional case–control study including 140 women with migraine (50% chronic) and 70 control women was conducted. Clinical migraine features, neurocognitive processes (e.g., attention), and executive functions (memory, mental inhibition, speed of processing) were evaluated. Pressure pain thresholds (PPTs) were bilaterally assessed at the temporalis muscle, lateral epicondyle, and tibialis anterior muscle. Heat (HPT) and cold (CPT) pain thresholds were assessed at the frontalis (trigeminal area) muscle. Thus, CPM was evaluated with the cold pressor test paradigm by analyzing changes in mechanical/thermal stimuli after a conditioned stimulus. Results: Significant group*time interactions not associated with neurocognitive process/executive function, educational level, and employment status were found for PPTs at the temporalis muscle (Wilk’s λ = 0.588, F[2,199] = 69.756, p < 0.001, n²p = 0.412, 1 − β = 0.999), lateral epicondyle (Wilk’s λ = 0.674, F[2,200] = 48.331, p < 0.001, n²p = 0.326, 1 − β = 0.999), and tibialis anterior (Wilk’s λ = 0.751, F[2,200] = 33.110, p < 0.001, n²p= 0.249, 1 − β = 0.999): PPTs were higher after the conditioned stimulus in all points in control women (increases ranging from 11% to 17%), whereas PPTs were lower after the conditioned stimulus in women with migraine (decrease from −7.5% to −0.1%) when compared with PPTs at baseline. Changes in HPT and CPT were small and not significant, ranging from 0.1% to 0.5%. Conclusion: This study revealed that women with episodic or chronic migraine showed CPM deficits particularly against mechanical stimuli when compared with pain-free women. Neurocognitive (e.g., attention) processes or executive functions (e.g., working memory, mental inhibition) did not modulate CPM activity in women with migraine. Full article

Background/Objective: Emerging evidence indicates that temporomandibular disorders (TMD) patients may present features of nociplastic pain (NP), characterized by central sensitization (CS)-related symptoms. This study aims to identify factors associated with CS-related symptoms and pain sensitivity in patients with TMD and NP-related features. Methods: In this cross-sectional study, 43 TMD patients were assessed for CS-related symptoms (CSI), proximal, distal, global pressure pain threshold (PPTs, algometer), orofacial pain intensity (VAS), jaw impairment (FAI), maximal isometric strength of four muscle groups (dynamometer), resting heart rate (RHR, chest band), kinesiophobia (TKS-11), physical activity level (IPAQ), anxiety (HADS), and sleep quality (PSQI). Associations were analyzed using linear regression models adjusted for gender, age, and symptoms duration. Results: Multivariate analysis showed that higher CSI was significantly associated with greater jaw impairment (Estimate 0.09, 95% CI 0.01 to 0.18) and higher pain intensity (Estimate 0.26, 95% CI 0.14 to 0.38). Lower PPT was significantly associated with lower grip strength (Proximal: Estimate 0.03, 95% CI 0.01 to 0.05; Distal: Estimate 0.07, 95% CI 0.01 to 0.14; Global: Estimate 2.44, 95% CI 0.57 to 4.31), and proximal PPT with higher RHR (Estimate −0.02, 95% CI −0.03 to 0). Conclusions: Association was found between CS-related symptoms and pain intensity and jaw impairment, while lower PPTs were related to decreased maximal isometric grip strength and elevated RHR, thus highlighting the need for multimodal treatment in TMD patients. Full article

Background/Objective: Kinesiotaping (KT) is widely used in sports and rehabilitation; however, evidence regarding its acute physiological effects on strength, pain sensitivity, and muscle oxygenation remains inconsistent. This study aimed to examine the acute effects of forearm KT on maximal grip strength, pressure pain threshold (PPT), and muscle oxygenation in healthy, physically active adults who performed a fatiguing exercise protocol. Methods: A randomized controlled trial was conducted with 28 participants (56 forearms), each randomly assigned to one of four conditions: KT applied proximal-to-distal, KT applied distal-to-proximal, placebo taping (no tension), or no taping (control). All assessments were performed within a single session, before and after a standardized forearm fatigue protocol. The outcomes included maximal and average grip strength (digital dynamometer), PPT (digital algometer), muscle oxygen saturation (SmO₂) and total hemoglobin (THb) measured using near-infrared spectroscopy (NIRS). Data were analyzed using two-way ANOVA (time × group) with Bonferroni-adjusted post hoc tests. Results: All groups showed significant within-group reductions in grip strength after the fatigue protocol (Δ −2.8 to −7.9 kg; all p ≤ 0.01), confirming the effectiveness of fatigue induction. Between-group analysis revealed a significant effect only for SmO₂ (p < 0.001; η²p = 0.317), with the proximal-to-distal KT group showing the largest post-fatigue increase (Δ +22.4; p < 0.001; Cohen’s d = 2.99) in SmO₂. However, a comparable increase in SmO₂ was also observed in the control group, suggesting a possible nonspecific reperfusion or oxygenation recovery effect. No between-group differences were observed in THb (p = 0.061), maximal grip strength (p = 0.092), average grip strength (p = 0.465), or PPT (p = 0.431). Conclusions: In healthy, physically active adults, forearm kinesiotaping did not produce significant acute effects on grip strength, pain threshold, or total hemoglobin levels following fatigue. Although a transient increase in SmO₂ was observed with proximal-to-distal taping, this change likely reflects a non-specific post-fatigue reperfusion response rather than a direct enhancement of perfusion. These findings support a physiological, rather than clinical, interpretation of KT’s effects. Future studies should include clinical or athletic populations and explore whether repeated applications produce cumulative adaptations in muscle oxygenation and recovery processes. Full article

Wearable robotic devices for rehabilitation and assistive applications face a critical challenge: discomfort induced by prolonged pressure at the human–robot interface. Conventional attachment systems with static straps or rigid cuffs frequently exceed pain tolerance thresholds, limiting clinical acceptance and patient adherence. This study presents a novel dynamic pressure modulation system using thermally activated Twisted and Coiled Artificial Muscles (TCAMs). The system integrates a lightweight lattice structure (0.1 kg) with biocompatible silicone coating incorporating two TCAMs fabricated from silver-coated nylon 6,6 fibers (Shieldex 235/36 × 4 HCB). Electrothermal activation via 2 A constant current induces axial contraction, dynamically regulating circumferential pressure from 0.05 kgf/cm² to 0.50 kgf/cm² within physiological comfort ranges. Experimental validation on a wrist-worn prototype demonstrates precise pressure control, rapid response (5–10 s), and thermal safety through 8 mm Ecoflex insulation. The system enables on-demand interface stiffening during robotic actuation and controlled pressure release during rest periods, significantly enhancing comfort and device tolerability. This approach represents a promising solution for clinically viable wearable robotic devices supporting upper limb rehabilitation and activities of daily living. Full article

Background: The magnitude of exercise-induced hypoalgesia (EIH) varies across individuals with knee osteoarthritis (OA). Impaired EIH may limit the pain-relieving effects of exercise and reduce exercise adherence. This study aimed to identify key factors associated with EIH in knee OA. Methods: This cross-sectional study included 119 participants (mean age 68 ± 10) with knee OA. Pre-exercise assessments, including validated questionnaires and quantitative sensory testing were undertaken. EIH was evaluated by measuring pressure pain thresholds (PPT) at the knee and forearm before and after quadriceps isometric resistance exercise. Linear regression and mixed models were used to identify factors associated with the magnitude of EIH and sources of variance in EIH. Results: EIH was greater at the knee compared to the forearm (p < 0.01), with considerable inter-individual variability. Older age, less anxiety, and expecting less exercise-induced pain were associated with increased EIH (all p < 0.05). However, all measured variables explained <20% of the variance in EIH, with unobserved between-participant factors estimated to account for ≥45% additional variance. Conclusions: Age, pre-exercise anxiety, and pain expectations are associated with the magnitude of EIH after resistance exercise in people with knee OA. However, the contribution of these factors was modest, with much of the inter-individual variance in EIH remaining unexplained. Full article

Objectives: Maxillary nerve block via the greater palatine canal (GPC) offers the potential for profound regional anesthesia of the maxilla but remains underutilized due to anatomical variability and technical complexity. The aim of this study was to explore the clinical feasibility, accuracy, and anesthetic effectiveness of a computer-guided approach by using CBCT-based surgical guides to access the pterygopalatine fossa via the GPC. Methods: Thirty-one patients underwent the procedure with patient-specific guides designed from cone-beam computerized tomography (CBCT) and intraoral scans. A 27G needle was directed through the guide to deliver 1.8 mL of 2% lidocaine with epinephrine 1:80.000. Pulpal anesthesia was assessed via electric pulp testing (EPT), and soft tissue anesthesia via pressure algometry at predefined oral and facial sites. Success was defined as absence of EPT response at maximum output and pressure pain threshold ≥ 700 g. To assess variations in anesthetic efficacy among multiple related groups, Cochran’s Q test and McNemar’s test were employed. Results: Successful needle placement was achieved in 30 out of 31 patients (96.7%) using the computer-guided approach, with a mean of 1.45 insertion attempts per case. Complete palatal soft tissue anesthesia was achieved in all subjects across the tested sites (100%). Pulpal anesthesia was most effective in posterior teeth, with success rates of 96.7% for first molars and 93.3% for first premolars, while the central incisor showed a reduced success rate of 50%. Transient visual disturbances occurred in three patients (10%), with no other adverse effects reported. Conclusions: These findings support the use of computer-guided GPC block as a method for achieving maxillary nerve anesthesia. Although anesthetic spread to anterior and buccal regions was limited, the technique demonstrated consistent effectiveness in the posterior maxilla, highlighting its potential utility in complex dental and surgical interventions requiring deep and long-lasting regional anesthesia. Full article

Background: Latent myofascial trigger points (MTrPs) are clinically relevant because they lower local pressure pain thresholds (PPTs), can perturb motor control, and may sustain shoulder symptoms even when overt pain is absent. However, even if previous studies assessed stiffness and mechanosensitivity differences between MTrPs and asymptomatic regions, objective patient-level cut-offs and diagnostic-accuracy metrics to distinguish latent MTrPs from adjacent asymptomatic tissue are lacking. Objective: To quantify the diagnostic accuracy of pressure algometry (PPT) and shear-wave elastography (SWE) for distinguishing latent MTrPs from adjacent asymptomatic tissue. Methods: A single-center cross-sectional study was conducted including 76 volunteers with ≥1 latent infraspinatus MTrP (assessed by following the current Delphi consensus criteria). The most sensitive latent MTrP and a control site 2 cm cranial was measured on the dominant side infraspinatus muscle in each participant. PPT and SWE were acquired with a standardized protocol (long-axis imaging, anisotropy control, minimal probe pressure; three captures per site; 1 cm rectangular ROI; operator blinded to site type). ROC analyses estimated areas under the curve (AUCs), Youden-optimal cut-offs, sensitivity, specificity, and likelihood ratios (LR+/−). Results: Latent MTrPs showed lower PPTs than controls (p < 0.001) and higher stiffness (shear modulus: p = 0.009; shear-wave speed: p = 0.022). PPT yielded AUC = 0.704 with an optimal cut-off of 47.5 N (sensitivity 0.75; specificity 0.592; LR+ 1.84; LR− 0.42), outperforming SWE metrics (shear modulus AUC 0.611; cut-off 23.6 kPa; sensitivity 0.632; specificity 0.605; LR+ 1.60; LR− 0.61; shear-wave speed AUC 0.601; cut-off 2.55 m/s; sensitivity 0.592; specificity 0.632; LR+ 1.61; LR− 0.65). Conclusions: In the infraspinatus, PPT provides moderate discrimination between latent MTrPs and adjacent asymptomatic tissue, whereas resting SWE—despite small mean differences—exhibited lower accuracy. These findings support mechanosensitivity as a primary measurable signal and position SWE as an adjunct. External validation across devices and operators, and multivariable models integrating sensory, imaging, and clinical features, are warranted. Full article

Bit pressure and rein tension-induced mouth pain in horses have recently become a significant welfare concern, fueling debates within the equestrian community and beyond. Evidence indicates that bits can cause pain-related behaviors and even oral lesions. Although studying pressure-induced pain in animals is challenging, the similarities in the physiology of pain processing (nociception) across mammals suggest that it is reasonable to assume that pain perception in humans and horses is principally comparable. Therefore, we compared human pressure pain detection thresholds (PPDTs) to reported rein pressures in equestrian sports as reported in the scientific literature. Reported rein tensions (kPa) range from a minimum of 91.2–107.87 to a maximum of 1314.09–4285.51, while human PPDTs (in kPa) are 232.4 for the face, 445.3 for the hand, and 535.5 for the foot. These comparisons reveal that only the lowest reported bit pressures would be pain-free for humans. Average to maximum pressures would cause strong to severe pain sensations in humans. Furthermore, data on pressure pain-induced stimulus response functions suggest that bit pressures commonly encountered in equestrian sports could cause lesions in humans, making them unacceptable in human experimentation. In conclusion, bit pressures as reported in the scientific literature would cause significant pain if applied to humans, raising welfare concerns for horses. Full article