ObjectiveThis study aimed to investigate central sensitization (CS) in individuals with lipedema using pressure pain threshold measurements and to examine its relationship with clinical features, sonographic findings, body composition, and Central Sensitization Inventory (CSI) scores.MethodsA total of 61 female patients with lipedema and 20 healthy controls were included in this cross-sectional study. Pressure pain threshold (PPT) was assessed at the thigh, pretibial region, and forearm using a manual algometer. Sonographic subcutaneous fat thickness was evaluated, and body composition parameters were assessed using bioelectrical impedance analysis. Clinical outcomes related to CS-including the CSI, Visual Analog Scale (VAS), Lower Extremity Functional Scale (LEFS), Short Form-12 (SF-12), and the Extended Nordic Musculoskeletal Questionnaire (NMQ-E)-were recorded. Linear mixed-effects models were used to compare PPT across groups, anatomical sites, and disease stages. Associations between PPT, CSI scores, body composition parameters, sonographic findings, and clinical measures were evaluated using Pearson correlation analyses.ResultsPatients with lipedema exhibited significantly lower PPT values across all anatomical regions, including the forearm, and significantly higher CSI scores compared with healthy controls (p < .001). Sonographic assessment confirmed increased subcutaneous fat thickness in the lower extremities of lipedema patients. Lipedema stage was not associated with overall PPT levels. However, lower forearm PPT and LEFS scores were observed in more advanced stages. Forearm PPT showed significant negative correlations with lean body mass, body fat mass, and total body water (p < .05), while no other significant associations were identified.ConclusionIndividuals with lipedema demonstrate features consistent with CS, characterized by reduced PPTs in both affected and non-affected regions together with elevated CSI scores. These findings suggest that altered pain processing may contribute to the widespread pain and functional limitations observed in lipedema, highlighting the importance of comprehensive assessment of CS in this population.

Background: Abdominal examination (AE) is an important component of clinical assessment in Traditional East Asian Medicine (TEAM), providing information on abdominal shape, tenderness, stiffness, and skin color. However, conventional AE relies largely on subjective judgment and lacks standardized quantitative indicators. This study aimed to quantitatively characterize abdominal physical features associated with the cold pattern (CP) using objective abdominal examination devices and to explore their potential role in supporting standardized pattern-related assessment. Methods: A case-control study was conducted including 63 patients with functional dyspepsia and 60 healthy controls. Participants were classified according to CP status using a validated cold-heat pattern identification questionnaire. Abdominal features were quantified using a digital algometer and a depth-based geometric assessment system, measuring algometric (pressure tolerance, indentation depth, stiffness), geometric (abdominal depth and curvature), and chromatic (CIE L*a*b*) parameters. Group differences were analyzed using generalized linear models adjusted for confounders. A two-stage LASSO logistic regression with nested 10-fold cross-validation was applied. Results: Individuals with CP showed significantly lower pressure tolerance, indentation depth, stiffness, and CIE a* values, along with a flatter abdominal contour. The integrated model achieved a cross-validated ROC-AUC of 0.777 (95% CI, 0.674-0.872), indicating moderate discriminative performance. Conclusions: Quantitative algometric, geometric, and chromatic abdominal features were significantly associated with CP. Objective abdominal measurements may complement conventional AE by providing quantitative physical indicators that support more standardized and clinically relevant pattern-related assessment. These findings highlight the potential clinical utility of quantitative abdominal evaluation in improving diagnostic consistency. Trial registration: KCT0003369. Registered 23 November 2018.

Local pain following orthodontic tooth movement negatively affects patients' experience and compliance. Pulsed neodymium-doped yttrium-aluminum-garnet (Nd:YAG) laser, based on photobiomodulation therapy (PBMT), can effectively relieve this pain. This study applied pulsed Nd:YAG laser at different frequencies to orthodontic sites and used digital techniques to evaluate differences in pain relief after tooth movement, aiming to screen the optimal frequency, optimize laser parameters, and provide scientific evidence for the analgesic efficacy of pulsed Nd:YAG laser in orthodontics. 96 patients receiving fixed orthodontic appliances for the first time, who met all inclusion criteria and gave informed consent, were enrolled in this randomized, double-blind, controlled trial. Participants were randomly assigned to one of three pulsed Nd:YAG laser groups-low frequency (10 Hz), medium frequency (15 Hz), or high frequency (20 Hz)-or to a continuous-wave semiconductor laser group (n = 24 each). Each participant further served as his or her own control: within each group, one randomly chosen side received active laser treatment while the contralateral side received sham treatment. A digital pressure algometer was used to measure pressure-pain thresholds (PPT) at the crown and the apex of the target teeth at 0 h, 24 h, 72 h, and 7 days after bracket placement, following intra-oral quantitative sensory testing (QST) protocols. Simultaneously, a visual analogue scale (VAS) and questionnaires were employed to record pain onset, peak pain time, pain disappearance time, and daily pain intensity. All data were analyzed using SPSS 27.0. 1. Intra-oral QST findings: Crown PPT on the treated side in the 10 Hz pulsed Nd:YAG group was significantly higher than that on the treated side in the continuous-wave semiconductor laser group (P < 0.05).In the 15 Hz pulsed Nd:YAG group, both apical and crown PPT values on the treated side were significantly higher than the corresponding values in the semiconductor laser group (P < 0.05). For all three pulsed Nd:YAG frequencies and the continuous-wave laser, PPT values on the treated side were significantly higher than those on the non-treated side (P < 0.05). 2. VAS and questionnaire findings: VAS scores on the treated side of the 10 Hz group were lower than those of the semiconductor laser group on days 2 and 3 (P < 0.05). VAS scores on the treated side of the 15 Hz group remained significantly lower than those of the semiconductor laser group throughout the observation period (days 1-6) (P < 0.05). From day 1 to day 6, VAS scores on the treated side were significantly lower than on the non-treated side in all four groups (P < 0.05). The 15 Hz group also exhibited significantly shorter pain disappearance time and overall pain duration compared with the semiconductor laser group (P < 0.05). 1. Under the PBMT paradigm, both pulsed Nd:YAG and continuous-wave semiconductor lasers effectively alleviate pain and associated symptoms after orthodontic tooth movement. 2. When total energy is kept constant (60 J), 15 Hz pulsed Nd:YAG laser shows promising analgesic effects with better reduction in tooth sensitivity and shorter pain duration than 10-20 Hz. Frequency and analgesia are not linearly correlated. The 15 Hz, 150 µs, 0.5 W setting appears to be a potentially optimal parameter for orthodontic pain relief.

Quantitative sensory testing (QST) has been used in horses to assess nociceptive responsiveness but its broader clinical application is limited by variability across anatomical sites, environmental conditions, operator technique, and behavioral endpoints. This study aimed to evaluate the feasibility, within-session repeatability, and test-retest reliability of thermal threshold (TT) and pressure pain threshold (PPT) testing in healthy Thoroughbred horses.

The use of robots is playing an increasingly important role in industrial manufacturing. Collaborative robots operated alongside humans can pose a hazard. Pain perception as an injury risk indicator is contingent on several factors, especially contact surface, anatomical region and the difference between superficial and deep tissue pain. In this article, we have conducted an experimental load study with human subjects in which we have analyzed these factors to enable the development of a pain-sensitive dummy for testing collaborative robot against biomechanical thresholds. For the load test, we used our established algometer setup with three different contact bodies (7 × 7 mm[2], 14 × 14 mm[2] and 24 × 24 mm[2]) to evaluate six anatomical regions of the arm. Subjects were instructed to activate a switch whenever they sensed pain after starting the test procedure. The algometer increased the force in 5 N/s increments. We used topical anesthetic to distinguish between superficial and deep tissue pain. We had 11 male subjects for measurements. The greatest force had to be applied with the medium-sized contact body to induce pain perception. Local anesthetization made it necessary to increase the force of the small and large contact bodies significantly. Our finding that peak force is a reliable indicator of the perception of pain caused by the medium-sized contact body indicates that the contact body's size affects peak force magnitude significantly.

Long-standing groin pain in athletes is often managed as a localized musculoskeletal tissue injury. Treatment-resistant symptoms and disability after return to sport suggest that other factors may also contribute. This study compared pain sensitivity, psychological factors, and muscle function between male athletes with long-standing groin pain (N = 20) and sex-, age-, and sports-matched controls (N = 20). Pressure-pain thresholds were assessed with a handheld algometer at the adductor longus muscle and origin, iliopsoas tendon, pubic bone, pubic symphysis, gluteus maximus muscle, and elbow. Pain detection and tolerance thresholds, temporal summation of pain, and conditioned pain modulation were assessed at the lower leg with cuff-pressure algometry. Catastrophizing, fear of movement, pain self-efficacy, depression, anxiety, stress, loneliness, and sleep were assessed. Maximal and explosive hip-adduction and -abduction strength were assessed. Between-group effects were expressed as Cohen's d or rank-biserial correlation r. Athletes with long-standing groin pain showed lower pressure-pain thresholds on the most painful side (d = 0.7-1.2), and lower pain detection threshold (d = 0.7). They reported more pain catastrophizing (r = 0.6), fear of movement (r = 0.4-0.5), depressive symptoms (r = 0.3-0.4), and lower pain self-efficacy (r = 0.6). Explosive strength was lower during both hip-adduction (d = 0.8) and hip-abduction (d = 0.7-0.9). At the group level, male athletes with long-standing groin pain showed altered pain sensitivity, adverse psychological factors, and lower explosive hip strength, despite inter-individual heterogeneity in these factors. Athletes with these characteristics may require a more biopsychosocial management than the traditional approach.