Multicenter Sudy on Ultrasound Characteristics of Acupoints in the Hand Yangming Meridia n and Related Factors

Multicenter Sudy on Ultrasound Characteristics of Acupoints in the Hand Yangming Meridia n and Related Factors | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Multicenter Sudy on Ultrasound Characteristics of Acupoints in the Hand Yangming Meridia n and Related Factors Fangqin Liu, Yunhao Luo, Jiaojun Yan, Zhengyan Wang, Shiping Wu, and 9 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8778712/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Objective: In vivo evidence defining the anatomical basis of acupoints remains limited. We characterized the ultrasonographic features of three Hand Yangming Meridian acupoints and analyzed influencing factors. Methods: This multicenter cross-sectional study included 110 healthy volunteers aged 18–65 without upper limb pathology, excluding pregnant individuals or those with coagulopathy. We inserted needles at LI4, LI8, and LI10 to elicit Deqi and measured depth, tissue structure, and elastic modulus using multimodal ultrasound versus a 5 mm reference point. Results: We included 110 healthy volunteers. Measurements showed median vertical distances from the Hegu (LI4), Xialian (LI8), and Shousanli (LI10) acupoints to the skin and radial surface were 1.72 (1.38, 1.96) cm and 0.93 (0.63, 1.24)cm, 1.64 (1.36, 1.95)cm and 0.43 (0.29, 0.60)cm, and 1.64 (1.36, 1.95)cm and 0.43 (0.29, 0.60)cm, respectively. These values showed no correlation with height, weight, age, or sex (p > 0.05). Acupoints localized predominantly within specific musculo-fascial structures: LI4 in the adductor pollicis (62.7%), LI8 in the supinator (41.8%), and LI10 in the fascia between the extensor carpi radialis longus and supinator (39.1%). This significant association with fascial structures (all P < 0.05) increased progressively along the meridian. Additionally, the mean elastic modulus at acupoints was significantly higher than at reference points (all P < 0.05). Conclusions: We identified stable ultrasonographic features within specific myofascial structures for these acupoints. These results support the meridian-connective tissue hypothesis and offer new methodological pathways for acupuncture research. Hegu acupoint Xia lian acupoint Shousanli acupoint Ultrasonic imaging Ultrasonic characteristics of acupoints Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Introduction Meridian theory provides a foundational framework in traditional medicine distinct from biomedical principles(1).Researchers continue to investigate connections between these paradigms, focusing on acupoints as critical functional nodes(2, 3).Imaging modalities form a vital component of this research (4, 5). and high-frequency ultrasound has recently emerged as a particularly promising, innovative technique(6)，Its recognised strengths, including real-time dynamic imaging, visualisation of microstructures, and multimodal capabilities, demonstrate considerable potential for characterising acupoint morphology in vivo(6-8). The Hand Yangming Large Intestine Meridian holds significant clinical importance, yet studies lack comprehensive ultrasonographic data regarding its primary acupoints—Hegu (LI4), Xialian (LI8), and Shousanli (LI10)(9, 10). By employing ultrasound technology for a comprehensive investigation, we aimed to observe the local ultrasonographic characteristics of these acupoints,explore their correlation with anatomical structures, examine the local mechanisms underlying meridian acupoints, and identify novel methods and approaches for imaging research on these points. Materials and Methods 1.1. Study Design The Ethics Committee of the Sichuan Hospital of Integrated Traditional Chinese and Western Medicine approved this study (Approval No. KY-2023-010). We conducted a prospective investigation across 10 medical centres. Between July 2024 and July 2025, we recruited 110 healthy volunteers. All participants underwent standardised acupuncture treatment at the Hegu (LI4), Xialian (LI8), and Shousanli (LI10) acupoints along the Hand Yangming Large Intestine Meridian, while we simultaneously observed and measured the sites using multimodal ultrasound technology. We obtained informed consent from each participant prior to the experiment. The research team created a standardised research manual to gather basic demographic information and multimodal ultrasound data. 1.2. Inclusion and Exclusion Criteria Inclusion Criteria: Healthy adults aged 18 to 70 years(11) ,who possess clear consciousness and do not have communication barriers. Exclusion Criteria: Individuals with coagulation dysfunction; sensory or language impairments; a history of fainting during acupuncture; excessive sensitivity to or fear of acupuncture; or a history of trauma, surgery, or structural abnormalities in the right forearm. 1.3. Instruments and Equipment We utilised the Mindray Resona 9 colour Doppler ultrasound diagnostic system (transducer L15-3WU) and the Mindray Resona 7 system (transducer L14-3WU).We employed acupuncture needles measuring 0.25 mm × 40 mm, sourced from Suzhou Medical Supplies Factory Co., Ltd. 1.4. Acupoint Localization and Acupuncture We conducted surface anatomical localisation and marking of acupoints in accordance with the Nomenclature and Location of Acupoints (GB/T12346-2021) standard(12-14). Acupuncturists possessing over five years of clinical experience performed the acupuncture procedures. We defined the onset of "Deqi" by subjects reporting sensations of "soreness, numbness, and distension," or by the practitioner detecting a distinct "astringent sensation" at the needle site(2) . We identified the acupoint location on ultrasound images as a 1 × 1 × 1 mm region centered on the needle tip position at the moment of “Deqi”(15) . For each subject, we selected the acupoints on the right hand. 1.5. Ultrasound Examination We captured images upon the onset of "Deqi" and documented the needle tip's position as the acupoint location. For the Hegu (LI4) acupoint, we measured the vertical distance from the skin (Vertical) and the distance to the radial midpoint of the second metacarpal bone (Level). At the Xialian (LI8) acupoint, we recorded the vertical distance from the skin (Vertical) and the vertical distance to the radial plane (Level). For the Shousanli (LI10) acupoint, we assessed the vertical distance from the skin (Vertical) and the perpendicular distance to the radial plane (Level). We calculated each measured value as the average of three consecutive measurements(16) .We performed colour Doppler flow imaging at the acupoint locations. Immediately following needle withdrawal, we performed shear wave elastography (SWE) at the acupoint location and at a reference point 5 mm horizontally to the right to obtain Young's modulus values (15). 1.6 Assessment of Research Data We aggregated data collected from each research centre and subsequently collated them by two researchers. We excluded cases with missing data, inadequate image clarity, or substantial artefacts from the analysis. Given the challenges associated with conducting inter-observer consistency tests, we employed a consensus approach to mitigate subjective diagnostic bias. Two investigators jointly interpreted the images. In instances of disagreement, they reached a decision through discussion; if consensus remained elusive, a final determination followed consultation with a third chief physician. We categorised the Hegu (LI4), Xialian (LI8), and Shousanli (LI10) acupoints into three distinct groups. Two-dimensional ultrasound (2D US) examination documented the anatomical structures at the acupoint locations, including muscle names and fascia types (see Figures 2a, 2b, and 2c, respectively). We classified muscles vertically from the skin surface into superficial and deep layers. At the Hegu acupoint, the superficial muscle was the dorsal interosseous muscle, while the deep muscle was the adductor pollicis. For both the Xialian and Shousanli acupoints, the superficial muscle was the extensor carpi radialis longus, and the deep muscle was the supinator muscle. If an acupoint lay within a muscle, we constructed a vertical line, passing through the acupoint and perpendicular to the skin surface. We divided the length of this line within the muscle into three equal segments, corresponding to the superficial, middle, and deep layers of the muscle. We classified acupoints as either fascial or non-fascial based on their location on fascial tissue. Additionally, we differentiated fascial types as intermuscular fascia and perimysium. We assessed Colour Doppler Flow Imaging (CDFI) using Adler's grading system for blood flow signals. We employed shear wave elastography (SWE) to measure the mean Young's modulus values at the acupoints and reference points immediately following needle withdrawal, utilising the transverse cross-section (Figure 1). 1.7 Statistical Analysis We conducted data entry and management using SPSS 25.0 statistical software. We utilised independent samples t-tests and one-way analyses of variance (ANOVA) to assess differences in demographic variables. For continuous variables exhibiting a skewed distribution, we reported data as median (M) and quartiles (Q1, Q3), and employed the Mann-Whitney U test for statistical analysis of two independent samples. We expressed categorical variables as frequency (n) and percentage (%), and analysed them using the Chi-square test or Fisher's exact test. We performed Spearman rank correlation analysis to evaluate the relationship between fascia and acupoints. All tests were two-tailed, with a P< 0.05 indicating statistical significance. Results 2.1 Basic information of the subjects The study included a total of 110 participants from 10 medical centres (Figure 1). The median age of the participants was 25 years, with an interquartile range of 21 to 31 years. Females comprised 61.8% (68/110) of the sample, while males constituted 38.2% (42/110). The median body mass index (BMI) was 21.63, with an interquartile range of 18.67 to 23.71. The observation indicators for the three acupoint groups, including measurements, acupoint locations, blood flow status, and elastic modulus values, exhibited no significant correlation with general characteristics such as sex, age, height, and weight (all P > 0.05) (Tables 1, 2, and 3). Table 1: Correlation between the observation indicators of Hegu acupoint and general conditions HG-Correlations HGvertical HGlevel needletipT detailedL needletipP detailedM CDFI MEAN11 MEAN12 year CI -0.072 0.055 0.041 0.046 0.165 -0.060 -0.105 0.126 0.131 P 0.457 0.570 0.671 0.631 0.084 0.534 0.274 0.189 0.171 high CI 0.218 0.023 -0.323 -0.296 0.112 -0.166 0.165 0.098 -0.037 P 0.128 0.870 0.021 0.035 0.434 0.243 0.247 0.492 0.795 weight CI 0.187 -0.055 -0.210 -0.188 -0.054 -0.124 0.095 0.306 0.128 P 0.193 0.702 0.138 0.186 0.705 0.385 0.509 0.029 0.370 sex CI 0.289 0.189 -0.111 -0.049 0.133 0.020 0.110 0.044 0.005 P 0.002 0.047 0.246 0.611 0.163 0.837 0.249 0.648 0.960 Table 2：Correlation between the observation indicators of the Xialian acupoint and general conditions XL-Correlations XLvertical XLlevel needletipT detailedL needletipP detailedM CDFI MEAN11 MEAN12 year CI -0.032 0.161 -0.021 -0.006 -0.073 -0.007 0.181 0.078 0.131 P 0.741 0.092 0.832 0.949 0.449 0.945 0.057 0.414 0.171 high CI 0.121 -0.061 -0.036 -0.044 0.088 -0.014 0.230 -0.037 -0.037 P 0.399 0.669 0.803 0.762 0.544 0.924 0.105 0.799 0.795 weight CI 0.198 0.103 -0.128 -0.108 0.066 -0.081 0.394 0.056 0.128 P 0.163 0.471 0.375 0.456 0.651 0.577 0.004 0.696 0.370 sex CI 0.167 0.001 0.066 0.115 -0.036 0.140 0.036 0.000 0.005 P 0.081 0.992 0.495 0.232 0.712 0.143 0.705 0.999 0.960 Table 3 Correlation between the observation indicators of the Shousanli acupoint and general conditions SSL-Correlations SSLvertical SSLlevel needletipT detailedL needletipP detailedM CDFI MEAN11 MEAN12 year CI -0.022 -0.005 -0.040 -0.056 0.087 -0.048 0.043 0.047 0.075 P 0.822 0.961 0.675 0.561 0.369 0.616 0.655 0.624 0.436 high CI 0.216 0.092 -0.022 -0.043 -0.005 -0.046 -0.037 0.083 -0.025 P 0.132 0.525 0.881 0.767 0.972 0.746 0.796 0.562 0.861 weight CI 0.235 0.123 -0.049 -0.209 -0.135 -0.218 0.104 0.080 0.086 P 0.100 0.394 0.732 0.140 0.346 0.124 0.466 0.577 0.548 sex CI 0.097 0.052 0.061 0.019 -0.064 0.035 -0.102 -0.011 -0.034 P 0.313 0.590 0.529 0.844 0.505 0.716 0.285 0.905 0.722 Note: In Table 1-3: vertical: the vertical distance between the acupoint and the skin; level: the vertical distance between the acupoint and the radius; needletipT, detailedL, needletipP, and detailedM: acupoint positions; CDFI: blood flow status; MEAN: mean elasticity; 11: acupoint point; 12: reference point 2.2 Two-dimensional ultrasound 2.2.1 Measurement values of acupuncture points Analysis showed significant differences in the distribution patterns of deep and superficial muscle layers between the Hegu acupoint and the Xialian/Shousanli acupoints (P 0.05) (refer to Table 5 for detailed information). Specifically, the Hegu acupoint was predominantly situated in the adductor pollicis muscle (62.7%), with 29.1% of occurrences in the superficial layer of this muscle. The Xialian acupoint was primarily located in the supinator muscle (41.8%), with 20.9% in the superficial layer of the supinator. The Shousanli acupoint was mainly positioned in the intermuscular fascia (39.1%), while 37.3% of cases lay in the fascia between the extensor carpi radialis longus and the supinator muscle (see Figure 4). Table 4 Acupuncture point measurement values (cm) HGlevel (110) XLlevel (110) SSLvertical (110) SSLlevel (110) M （Q 1 ,Q 3 ） 1.72 （1.38,1.96） 0.93 （0.63,1.24） 1.64 （1.36,1.95） 0.43 （0.29,0.60） 0.66 （0.45,0.84） Note: Vertical refers to the distance between the acupoint and the skin. Level denotes the distance between the acupoint and the radius, with the Hegu acupoint measured from the midpoint of the radius. Q₁represents the first percentile, while Q₃indicates the third percentile. HG stands for Hegu, XL denotes the Xialian acupoint, and SSL refers to the Shousanli acupoint. 2.2.2 Muscular Architecture at Acupoint Sites showed significant differences in the distribution patterns of deep and superficial muscle layers between Hegu acupoint and Xiaolian/Shousanli acupoints (P 0.05) (refer to Table 5 for detailed information). Specifically, Hegu acupoint was predominantly situated in the adductor pollicis muscle (62.7%), with 29.1% of occurrences in the superficial layer of this muscle. Xiaolian acupoint was primarily located in the supinator muscle (41.8%), with 20.9% in the superficial layer of the supinator. Shousanli acupoint was mainly positioned in the intermuscular fascia (39.1%), while 37.3% of cases were found in the fascia between the extensor carpi radialis longus and the supinator muscle (see Figure 4). Table 5 :Analysis of the anatomical structure of acupoint locations variables HG * ＃ XL *☆ SSL ＃ ☆ statistic P Dissect 25.57 ＜0.001 1 14（ 12.7） 29（26.4） 34（30.9） 2 69（62.7） 46（41.8） 33（30.0） 3 27（24.5） 35（33.3） 43（39.1） Note: 1: Superficial muscles, 2: Deep muscles, 3: Intermuscular fascia; # : Comparison of the location characteristics between HG and SSL acupoints, P < 0.001; * : Comparison of the location characteristics between HG and XL acupoints, P 0.05 (0.187); Most of the Hegu (LI4) acupoints are located in the deep muscles, while the Xialian (LI8) and Shousanli (LI10) acupoints are distributed relatively evenly. 2 .2.3 Correlation between Acupoint Location and Fascia Upon contact between the needle tip and the fascia, subjects reported a distinct "Deqi" sensation, suggesting a strong correlation between acupoint locations and fascial structures.We found statistically significant differences among the three groups concerning the presence of acupoints on fascia (P=0.003). The proportions of acupoints associated with fascia were 50.9% for Hegu (LI4), 68.2% for Xialian (LI8), and 71.8% for Shousanli (LI10) (see Table 6). Table 6 Analysis of the correlation between acupoints and fascia Comparison of Acupoint Parameter（ Fascial/non-fascia） Variables Fascial (n=208 ) non-fascia(n=122 ) Statistic P Local 11.864 0.003 HG +* 56（50.9） 54（49.1） XL #* 75（68.2） 35（31.8） SSL #+ 79（71.8） 31（28.2） Note: Fascial: fascial group; non-fascia: non-fascial group. + indicates the pairwise comparison between HG and SSL, with P < 0.03; * indicates the pairwise comparison between HG and XL, with P 0.05. 2.3 Shear Wave Elastography (SWE) We observed a statistically significant difference in the mean elastic modulus (MEAN) between the acupoint and non-acupoint locations of the Shousanli acupoint (P < 0.05). Specifically, the P values for the Hegu and Xialian acupoints were 0.048 and 0.047, respectively, indicating potential statistical differences between the acupoint sites and their corresponding reference points for both Hegu and Shousanli acupoints. Furthermore, the median elastic modulus value at acupoint sites exceeded that at reference points (see Table 7). Table 7 Comparison of elastic mean values between acupoints and reference points Variables 1 2 Statistic P HG 2.76 (2.20，3.29) 2.66 (2.06，3.30) 6.038 0.048 XL 2.86 (2.25，3.49) 2.79 (2.17，3.32） 6.030 0.047 SSL 2.83 (2.36，3.36) 2.69 (2.19，3.16) 6.797 0.033 Note: 1: Acupoint, 2: Reference point 2.4. Color Doppler Flow Imaging According to Adler’s grading of blood flow signals in Color Doppler Flow Imaging, the acupoint sites were primarily marked by a lack of discernible blood flow signals. Pairwise comparisons of blood flow signal distribution among the acupoints showed no statistically significant differences (P > 0.05) (see Table 8). Table 8:Color flow grading of acupoints Adler 0 I II statistic P acupoint 1.65 0.438 HG 97(88.2) 10(9.1) 3(2.7) XL 103(92.7) 7(6.4) 1(0.9) SSL 98(89.1) 11(10.0) 1(0.9) Note: χ²: Chi-square test, 0: no obvious blood flow, I: a small amount (punctate) of blood flow, II: a moderate amount (rod-shaped) of blood flow Discussion Ultrasound imaging is distinguished by its real-time dynamic and multimodal capabilities. In recent years, its application in research on meridians and acupoints has grown, revealing promising prospects. This study enrolled a relatively large cohort of healthy participants and utilized multimodal ultrasound techniques to investigate acupoints along the Hand Yangming Meridian. We identified the sonographic characteristics of these acupoints, thereby partially elucidating the relationship between meridian acupoints and anatomical structures, as well as the biomechanical effects of acupuncture. 3 .1 Grayscale Ultrasound Measurements at the acupoints demonstrated relatively fixed locations, exhibiting stability despite potential influencing factors, with values clustering around the median.We found no significant correlation between these measurements and general characteristics such as age, sex, or body fat percentage.This finding challenges the traditional belief that the effects of acupuncture depend on individualized sensations; instead, it implies a connection between acupoint locations and specific tissue structures(17). Further analysis revealed that the three acupoints were primarily situated within muscles: Hegu (LI4) in the adductor pollicis, Xialian (LI8) in the supinator muscle, and Shousanli (LI10) in the intermuscular fascia. Hegu notably had more deep muscle locations compared to Xialian and Shousanli, where the proportion of intermuscular locations increased. This distribution aligns with the local anatomical environment of each acupoint, suggesting that acupoints' functional specificity may derive from their underlying structural foundation. Using high-frequency ultrasound imaging, we consistently observed a strong correlation between acupoints and fascia, particularly intermuscular septa and perimysium. Subjects were more prone to experiencing the "Deqi" sensation when the acupuncture needle tip made contact with the fascia. It is important to acknowledge that fascia visualization on ultrasound may not be definitive; acupoints categorized as non-fascia may still be situated on delicate fascial structures. Furthermore, an analysis comparing the fascial compositions of three acupoints indicated a progressive increase in fascial association for acupoints located closer to the meridian origin. This observation aligns with traditional meridian theory and supports the fasciology concept that "meridian pathways align with the fascial network distribution"(18-20) . Fascia, as a continuous three-dimensional connective tissue network, not only provides structural support for acupoints but also may engage in local signal transduction and regulatory functions through the nerve endings, capillaries, and immune cells embedded within it (21, 22), Thus, fascia plays a crucial role in eliciting “Deqi” and generating therapeutic effects during acupuncture. We assert that fascial structures occupy a significant position within the framework of meridian acupoints, although the overlap is not entirely comprehensive. While the pathways of meridian acupoints correlate with fascia, the extent of this correlation varies among different meridian segments. Notably, the degree of overlap with fascia tends to increase progressively when moving proximally along the meridian. This observation provides new insights and directions for research on ultrasound and meridians(23-25) . Ultrasound facilitates precise visualization of “Deqi” locations, aiding in identifying the primary nerves innervating the acupoint region. In this study, needle manipulation sites and the sensation of “Deqi” were consistently located within the innervation territory of the deep branch of the ulnar nerve. This discovery offers valuable insights for investigating the neuromodulation mechanisms of acupuncture in clinical practice. 3.2. Color Doppler Flow Imaging Acupoints are located within the superficial soft tissues. High-frequency color Doppler ultrasound typically demonstrates hypovascularity, with blood flow grading primarily ranging from 0 to 1. Although previous studies have indicated that acupuncture therapy can induce alterations in local microcirculation(26-28) , the present study found no significant differences in color blood flow signals among various acupoints or between acupoints and reference points. This lack of difference may be due to the sensitivity limitations of the blood flow detection technology we utilised. In addition to color Doppler, ultrasonic assessment of local blood flow encompasses techniques such as Superb Microvascular Imaging (SMI) and Contrast-Enhanced Ultrasound (CEUS). CEUS, in particular, offers distinct advantages for detecting local circulation. However, the use of CEUS was clearly constrained by ethical considerations, given that the study subjects were healthy volunteers(29, 30). Our team is currently undertaking further in-depth investigations using alternative experimental approaches. 3.3. Shear Wave Elastography In this study, we quantitatively compared Young's modulus between acupoint and non-acupoint regions using shear wave elastography. The results indicated that the elastic values at the acupoint sites were significantly higher than those at the reference points located 0.5 cm away horizontally for all three acupoints. Numerous researchers propose that needling acupoints may trigger the discharge of fine nerves in the area, resulting in soft tissue contraction and an associated increase in Young’s modulus values. This phenomenon is reflected in elastography as a characteristic increase in stiffness at the center, accompanied by a centrifugal decrease(31) .At the same time, this difference may also stem from the denser fascial tissue within the acupoint region , a higher density of nerve endings and microvascular networks , as well as the inherent specificity of the mechanical properties of the tissues in this area(31). Elastography thus offers a potential quantitative imaging biomarker for the objective identification of acupoints and further substantiates the distinguishability of acupoints in terms of tissue texture. Limitations The present study serves as a preliminary exploration of in vivo acupoint observation through multimodal ultrasound technology and is subject to certain limitations. For example, the potential of color Doppler detection techniques necessitates further investigation. Additionally, this study did not examine acupoints under varying conditions, nor did it incorporate a disease group for comparative analysis. These limitations highlight important avenues for future research. Conclusion Acupoints located on the Hand Yangming Meridian display distinct sonographic characteristics and stable anatomical positions. They exhibit a close association with fascia, adhere to a consistent pattern along the proximal trajectory of the meridian, and possess unique mechanical properties as demonstrated by elastography. This study establishes a method for the visualization and quantitative assessment of acupoints based on ultrasound features, thereby providing imaging and biomechanical support for the "meridian-connective tissue" hypothesis. Moreover, these findings lay a new methodological foundation for investigating the mechanisms of acupuncture and for the integration of traditional Chinese and Western medicine. Declarations Acknowledgements Not applicable. Author contributions Liu Fangqin and Luo Yunhao: Co-first authors. They contributed equally to the study design, coordinated data acquisition, performed statistical analysis, and drafted the manuscript.Yan Jiaojun and Wang Zhengyan: Contributed to participant recruitment, ultrasonographic data acquisition, and critical revision of the manuscript.Wu Shiping, Li Shuting, Nan Xuhong, Cheng Chunxia, Fu Xuerong, Lu Yaling, Xia Xuemei, Du Huan, and Fan Zhengchao: Contributed to participant recruitment, ultrasonographic examination, and data collection at their respective centres.Qiao Lang: Corresponding author. He conceived and supervised the study, secured funding, coordinated the multicentre collaboration, and critically revised the manuscript. Dr. Qiao serves as the guarantor of the work, taking full responsibility for the integrity of the data and the accuracy of the data analysis. Funding This work was supported by The project on Sichuan Provincial Natural Science Foundation-Research on AI Recognition of Acupoints on the Hand-Yangming Meridian and Specificity of Acupoint Effects Based on Ultrasound Multimodal Technology（under Grant No. 2024NSFSC0725） Data availability The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request. Trial registration : The research was registered with the International Traditional Medicine Clinical Trial Registry (ITMCTR2026000042). This study has adhered to the Declaration of Helsinki. Free and informed consent was obtained from all the participants. Ethical approval and consent to participate Ethical approval was sought from the Ethics Committee of Sichuan Hospital of Integrated Traditional Chinese and Western Medicine approved this study (Approval No. KY-2023-010). Consent for publication Not applicable. 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Microscopy of structures surrounding typical acupoints used in clinical practice and electron microscopic evaluation of acupuncture needles. Clin Anat. 2022;35(3):392-403. Choi KH, Cho SJ, Kim M, Kwon OS, Kang SY, Seo SY, et al. What is the analgesic range of acupuncture stimulus for treating acute pain? Front Hum Neurosci. 2023;17:1281832. Ma SX. Stimuli-evoked NOergic molecules and neuropeptides at acupuncture points and the gracile nucleus contribute to signal transduction of propagated sensation along the meridian through the dorsal medulla-thalamic pathways. J Integr Med-JIM. 2024;22(5):515-22. Wang H, Wang E, Zhang B. The theoretical basis, experimental verification and significance of revealing meridians. Zhongguo zhen jiu = Chinese acupuncture & moxibustion. 2018;38(4):391-7. Feng Y, Xia Y, Fan B, Li S, Zhang Z, Fang J. Global trends and performances of infrared imaging technology studies on acupuncture: a bibliometric analysis. Front Neurosci. 2024;18:1387752. Kubota T, Mori H, Morisawa T, Hanyu K, Kuge H, Watanabe M, et al. Influence of electroacupuncture stimulation on skin temperature, skin blood flow, muscle blood volume and pupil diameter. Acupunct Med. 2020;38(2):86-92. Sandberg M, Lundeberg T, Lindberg LG, Gerdle B. Effects of acupuncture on skin and muscle blood flow in healthy subjects. Eur J Appl Physiol. 2003;90(1-2):114-9. Han R, Hu J. Acupuncture: An Overview on Its Functions, Meridian Pathways and Molecular Mechanisms. Am J Chin Med. 2024;52(5):1215-44. Lu L, Chen X, Gong H, Cai Z, Luo T, He P, et al. A Comparative Study of Sononeoperfusion Effects Induced by Diagnostic and Therapeutic Ultrasound-Stimulated Microbubbles. J Ultrasound Med. 2025. van Elburg B, Bruil K, Lajoinie G, Borden M, Versluis M, Segers T. Tuning the Shell Elasticity of Phospholipid-Coated Microbubbles via Palmitic Acid Doping. Langmuir. 2025;41(42):28313-21. Yunshan L, Chengli X, Peiming Z, Haocheng Q, Xudong L, Liming L. Integrative research on the mechanisms of acupuncture mechanics and interdisciplinary innovation. Biomedical Engineering Online. 2025;24(1). Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8778712","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":630648728,"identity":"236feb2a-c9cc-4a2e-a546-f9514a142121","order_by":0,"name":"Fangqin Liu","email":"","orcid":"","institution":"成都中医药大学医学与生命科学学院","correspondingAuthor":false,"prefix":"","firstName":"Fangqin","middleName":"","lastName":"Liu","suffix":""},{"id":630648729,"identity":"e5805949-f27e-4dd0-8f6c-1910f950cbb5","order_by":1,"name":"Yunhao 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Qiao","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAtElEQVRIiWNgGAWjYDACdiBOYGCQY2NvP0CkFmaQlgQGYz6eMwkkaAFakzhPwsGAOB18h9kffnj4oza9TQKo8UfFNsJaJA/zGEskJBzPbZNuPMDYc+Y2YS0Gh3nYgH45ltsmcyCBmbGNKC3sz0Ba0tkkEgyI1cJgBtRSk0C8Fohf0g4YtgED+SBRfuE73v7w4w+bOnn59vaDD35UEKGF4QCYPIzEJlJLHXGKR8EoGAWjYGQCADIpO9OdcrM2AAAAAElFTkSuQmCC","orcid":"","institution":"Sichuan Integrative Medicine Hospital","correspondingAuthor":true,"prefix":"","firstName":"Lang","middleName":"","lastName":"Qiao","suffix":""}],"badges":[],"createdAt":"2026-02-03 17:08:45","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8778712/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8778712/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":108173714,"identity":"e968c7dc-4bf8-4c6a-b028-5f45bffc07bc","added_by":"auto","created_at":"2026-04-30 07:31:52","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":78210,"visible":true,"origin":"","legend":"\u003cp\u003eResearch flow chart.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-8778712/v1/77f3a697c86036670381cc92.png"},{"id":108182779,"identity":"20043c7d-ed69-433b-a719-3f1fcd749ba3","added_by":"auto","created_at":"2026-04-30 08:59:32","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":982466,"visible":true,"origin":"","legend":"\u003cp\u003eImage acquisition diagram. The arrow points to the acupoint locations: a: Hegu, b: Xialian, c: Shousanli. The image acquisition diagram from left to right are grayscale ultrasound image, acupoint measurement image, color Doppler flow image, and elastic shear wave image.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-8778712/v1/bee30239a9e5226be25276ea.png"},{"id":108173716,"identity":"2e0fafa4-5d68-496d-a643-354398630c60","added_by":"auto","created_at":"2026-04-30 07:31:52","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":184297,"visible":true,"origin":"","legend":"\u003cp\u003eA scatter plot of the measured values of three groups of acupoints.In the figure, the abscissa represents the vertical distance from the acupoint to the radius (level), and the ordinate represents the vertical distance from the acupoint to the skin (vertical).\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-8778712/v1/9f74d55f8da51da8b45b1be5.png"},{"id":108183098,"identity":"f262fa49-a229-42a2-a02e-ab73cdd0ccb6","added_by":"auto","created_at":"2026-04-30 08:59:47","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":750655,"visible":true,"origin":"","legend":"\u003cp\u003eThe arrow indicates the acupoint's location.a: Grayscale image of the acupoint. b: Measurement image of the acupoint. (1): The Hegu acupoint is situated in the superficial layer of the thenar muscle (29.1%). (2): The Shousanli acupoint is positioned in the fascia between the extensor carpi radialis longus muscle and the supinator muscle (37.3%). (3): The Xialian acupoint is found in the superficial layer of the supinator muscle (20.9%).\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-8778712/v1/9a74008999c16f51827f27af.png"},{"id":108182844,"identity":"59815f8c-d1b9-4617-9f24-4eb905e70137","added_by":"auto","created_at":"2026-04-30 08:59:38","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":23534,"visible":true,"origin":"","legend":"\u003cp\u003eTrend chart of the proportion of fascia at acupoints Vertical axis: percentage Horizontal axis: acupoint point 1: Hegu acupoint 2: Xialian acupoint\u003c/p\u003e\n\u003cp\u003e3: Shousanli acupoint Fascial: fascia\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-8778712/v1/16d061d468632cd84b46eb6d.png"},{"id":109209552,"identity":"2960ef45-4552-44da-92d9-d99264549af8","added_by":"auto","created_at":"2026-05-13 15:29:21","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2494187,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8778712/v1/b66cc8f7-3684-44c7-af43-731dd9e66320.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Multicenter Sudy on Ultrasound Characteristics of Acupoints in the Hand Yangming Meridia n and Related Factors","fulltext":[{"header":"Introduction","content":"\u003cp\u003eMeridian theory provides a foundational framework in traditional medicine distinct from biomedical principles(1).Researchers continue to investigate connections between these paradigms, focusing on acupoints as critical functional nodes(2, 3).Imaging modalities form a vital component of this research\u0026nbsp;(4, 5). and high-frequency ultrasound has recently emerged as a particularly promising, innovative technique(6)，Its recognised strengths, including real-time dynamic imaging, visualisation of microstructures, and multimodal capabilities, demonstrate considerable potential for characterising acupoint morphology in vivo(6-8).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe Hand Yangming Large Intestine Meridian holds significant clinical importance, yet studies lack comprehensive ultrasonographic data regarding its primary acupoints\u0026mdash;Hegu (LI4), Xialian (LI8), and Shousanli (LI10)(9, 10). By employing ultrasound technology for a comprehensive investigation, we aimed to observe the local ultrasonographic characteristics of these acupoints,explore their correlation with anatomical structures, examine the local mechanisms underlying meridian acupoints, and identify novel methods and approaches for imaging research on these points.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cp\u003e\u003cstrong\u003e1.1. Study Design\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe Ethics Committee of the Sichuan Hospital of Integrated Traditional Chinese and Western Medicine approved this study (Approval No. KY-2023-010).\u0026nbsp;We conducted a prospective investigation across 10 medical centres. Between July 2024 and July 2025,\u0026nbsp;we recruited 110 healthy volunteers. All participants underwent standardised acupuncture treatment at the Hegu (LI4), Xialian (LI8), and Shousanli (LI10) acupoints along the Hand Yangming Large Intestine Meridian, while\u0026nbsp;we simultaneously observed and measured the sites using multimodal ultrasound technology.\u0026nbsp;We obtained informed consent from each participant prior to the experiment. The research team created a standardised research manual to gather basic demographic information and multimodal ultrasound data.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1.2. Inclusion and Exclusion Criteria\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eInclusion Criteria:\u003c/strong\u003e Healthy adults aged 18 to 70 years(11) ,who possess clear consciousness and do not have communication barriers.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eExclusion Criteria:\u003c/strong\u003e Individuals with coagulation dysfunction; sensory or language impairments; a history of fainting during acupuncture; excessive sensitivity to or fear of acupuncture; or a history of trauma, surgery, or structural abnormalities in the right forearm.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1.3. Instruments and Equipment\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe utilised\u0026nbsp;the Mindray Resona 9 colour Doppler ultrasound diagnostic system (transducer L15-3WU) and the Mindray Resona 7 system (transducer L14-3WU).We employed acupuncture needles measuring 0.25 mm × 40 mm, sourced from Suzhou Medical Supplies Factory Co., Ltd.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1.4. Acupoint Localization and Acupuncture\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe conducted \u0026nbsp;surface anatomical localisation and marking of acupoints in accordance with the Nomenclature and Location of Acupoints (GB/T12346-2021) standard(12-14).\u0026nbsp;\u0026nbsp;Acupuncturists possessing over five years of clinical experience performed the acupuncture procedures.\u0026nbsp;\u0026nbsp;We defined\u0026nbsp;\u0026nbsp;the onset of \"Deqi\" by subjects reporting sensations of \"soreness, numbness, and distension,\" or by the practitioner detecting a distinct \"astringent sensation\" at the needle site(2)\u0026nbsp;.\u0026nbsp;We identified\u0026nbsp;the acupoint location on ultrasound images as a 1 × 1 × 1 mm region centered on the needle tip position at the moment of\u0026nbsp;“Deqi”(15)\u0026nbsp;. For each subject,\u0026nbsp;we selected\u0026nbsp;the acupoints on the right hand.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1.5. Ultrasound Examination\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe captured images upon the onset of \"Deqi\" and documented the needle tip's position as the acupoint location. For the Hegu (LI4) acupoint, we measured the vertical distance from the skin (Vertical) and the distance to the radial midpoint of the second metacarpal bone (Level). At the Xialian (LI8) acupoint, we recorded \u0026nbsp;the vertical distance from the skin (Vertical) and the vertical distance to the radial plane (Level). For the Shousanli (LI10) acupoint, \u0026nbsp;we assessed \u0026nbsp;the vertical distance from the skin (Vertical) and the perpendicular distance to the radial plane (Level). We calculated each measured value as the average of three consecutive measurements(16)\u0026nbsp;.We performed\u0026nbsp;colour Doppler flow imaging at the acupoint locations. Immediately following needle withdrawal, we performed shear wave elastography (SWE) at the acupoint location and at a reference point 5 mm horizontally to the right to obtain Young's modulus values\u0026nbsp;(15).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1.6\u003c/strong\u003e\u003cstrong\u003eAssessment of Research Data\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe aggregated data collected from each research centre and subsequently collated them by two researchers.\u0026nbsp;We excluded cases with missing data, inadequate image clarity, or substantial artefacts from the analysis. Given the challenges associated with conducting inter-observer consistency tests,\u0026nbsp;we employed a consensus approach to mitigate subjective diagnostic bias. Two investigators jointly interpreted the images. In instances of disagreement,\u0026nbsp;they reached a decision through discussion; if consensus remained elusive, a final determination followed consultation with a third chief physician.\u003c/p\u003e\n\u003cp\u003eWe categorised the Hegu (LI4), Xialian (LI8), and Shousanli (LI10) acupoints into three distinct groups. Two-dimensional ultrasound (2D US) examination documented the anatomical structures at the acupoint locations, including muscle names and fascia types (see Figures 2a, 2b, and 2c, respectively). We classified \u0026nbsp;muscles vertically from the skin surface into superficial and deep layers. At the Hegu acupoint, the superficial muscle was the dorsal interosseous muscle, while the deep muscle was the adductor pollicis. For both the Xialian and Shousanli acupoints, the superficial muscle was the extensor carpi radialis longus, and the deep muscle was the supinator muscle. If an acupoint lay within a muscle, we constructed a vertical line, passing through the acupoint and perpendicular to the skin surface. We divided the length of this line within the muscle into three equal segments, corresponding to the superficial, middle, and deep layers of the muscle. We classified acupoints as either fascial or non-fascial based on their location on fascial tissue. Additionally, we differentiated fascial types as intermuscular fascia and perimysium. We assessed Colour Doppler Flow Imaging (CDFI) using Adler's grading system for blood flow signals. We employed shear wave elastography (SWE) to measure the mean Young's modulus values at the acupoints and reference points immediately following needle withdrawal, utilising the transverse cross-section (Figure 1).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1.7\u003c/strong\u003e\u003cstrong\u003eStatistical Analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe conducted \u0026nbsp;data entry and management using SPSS 25.0 statistical software. \u0026nbsp;We utilised \u0026nbsp;independent samples t-tests and one-way analyses of variance (ANOVA) to assess differences in demographic variables. For continuous variables exhibiting a skewed distribution, \u0026nbsp; we reported \u0026nbsp;data as median (M) and quartiles (Q1, Q3), and \u0026nbsp;employed \u0026nbsp;the Mann-Whitney U test for statistical analysis of two independent samples. \u0026nbsp;We expressed \u0026nbsp;categorical variables as frequency (n) and percentage (%), and \u0026nbsp;analysed \u0026nbsp;them using the Chi-square test or Fisher's exact test. \u0026nbsp;We performed \u0026nbsp;Spearman rank correlation analysis to evaluate the relationship between fascia and acupoints. All tests were two-tailed, with a P\u0026lt; 0.05 indicating statistical significance. \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cstrong\u003e2.1 Basic information of the subjects\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study included \u0026nbsp;a total of 110 participants from 10 medical centres (Figure 1). The median age of the participants was 25 years, with an interquartile range of 21 to 31 years. Females comprised 61.8% (68/110) of the sample, while males constituted 38.2% (42/110). The median body mass index (BMI) was 21.63, with an interquartile range of 18.67 to 23.71. The observation indicators for the three acupoint groups, including measurements, acupoint locations, blood flow status, and elastic modulus values, exhibited no significant correlation with general characteristics such as sex, age, height, and weight (all P \u0026gt; 0.05) (Tables 1, 2, and 3).\u003c/p\u003e\n\u003cp\u003eTable 1: Correlation between the observation indicators of Hegu acupoint and general conditions\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"588\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"10\" style=\"width: 535px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eHG-Correlations\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 52px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 49px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 29px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003eHGvertical\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 62px;\"\u003e\n \u003cp\u003eHGlevel\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003eneedletipT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 62px;\"\u003e\n \u003cp\u003edetailedL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003eneedletipP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003edetailedM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 62px;\"\u003e\n \u003cp\u003eCDFI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 55px;\"\u003e\n \u003cp\u003eMEAN11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 52px;\"\u003e\n \u003cp\u003eMEAN12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 49px;\"\u003e\n \u003cp\u003eyear\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 29px;\"\u003e\n \u003cp\u003eCI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e-0.072\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.055\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.041\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.046\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.165\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e-0.060\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e-0.105\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 55px;\"\u003e\n \u003cp\u003e0.126\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 52px;\"\u003e\n \u003cp\u003e0.131\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 29px;\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.457\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.570\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.671\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.631\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.084\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.534\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.274\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 55px;\"\u003e\n \u003cp\u003e0.189\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 52px;\"\u003e\n \u003cp\u003e0.171\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 49px;\"\u003e\n \u003cp\u003ehigh\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 29px;\"\u003e\n \u003cp\u003eCI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.218\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.023\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e-0.323\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e-0.296\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.112\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e-0.166\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.165\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 55px;\"\u003e\n \u003cp\u003e0.098\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 52px;\"\u003e\n \u003cp\u003e-0.037\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 29px;\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.128\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.870\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.021\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.035\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.434\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.243\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.247\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 55px;\"\u003e\n \u003cp\u003e0.492\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 52px;\"\u003e\n \u003cp\u003e0.795\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 49px;\"\u003e\n \u003cp\u003eweight\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 29px;\"\u003e\n \u003cp\u003eCI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.187\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e-0.055\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e-0.210\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e-0.188\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e-0.054\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e-0.124\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.095\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 55px;\"\u003e\n \u003cp\u003e0.306\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 52px;\"\u003e\n \u003cp\u003e0.128\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 29px;\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.193\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.702\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.138\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.186\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.705\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.385\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.509\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 55px;\"\u003e\n \u003cp\u003e0.029\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 52px;\"\u003e\n \u003cp\u003e0.370\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 49px;\"\u003e\n \u003cp\u003esex\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 29px;\"\u003e\n \u003cp\u003eCI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.289\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.189\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e-0.111\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e-0.049\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.133\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.020\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.110\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 55px;\"\u003e\n \u003cp\u003e0.044\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 52px;\"\u003e\n \u003cp\u003e0.005\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 29px;\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.002\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.047\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.246\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.611\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.163\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.837\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.249\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 55px;\"\u003e\n \u003cp\u003e0.648\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 52px;\"\u003e\n \u003cp\u003e0.960\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;Table 2：Correlation between the observation indicators of the Xialian acupoint and general conditions\u003c/p\u003e\n\u003cdiv align=\"center\"\u003e\n \u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"593\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"10\" style=\"width: 542px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eXL-Correlations\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 51px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 53px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 33px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 56px;\"\u003e\n \u003cp\u003eXLvertical\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 61px;\"\u003e\n \u003cp\u003eXLlevel\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 57px;\"\u003e\n \u003cp\u003e\u0026nbsp;needletipT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 57px;\"\u003e\n \u003cp\u003e\u0026nbsp;detailedL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59px;\"\u003e\n \u003cp\u003eneedletipP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 63px;\"\u003e\n \u003cp\u003edetailedM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 52px;\"\u003e\n \u003cp\u003eCDFI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 52px;\"\u003e\n \u003cp\u003eMEAN11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 51px;\"\u003e\n \u003cp\u003eMEAN12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 53px;\"\u003e\n \u003cp\u003eyear\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 33px;\"\u003e\n \u003cp\u003eCI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 56px;\"\u003e\n \u003cp\u003e-0.032\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 61px;\"\u003e\n \u003cp\u003e0.161\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 57px;\"\u003e\n \u003cp\u003e-0.021\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 57px;\"\u003e\n \u003cp\u003e-0.006\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 59px;\"\u003e\n \u003cp\u003e-0.073\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 63px;\"\u003e\n \u003cp\u003e-0.007\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 52px;\"\u003e\n \u003cp\u003e0.181\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 52px;\"\u003e\n \u003cp\u003e0.078\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0.131\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 33px;\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 56px;\"\u003e\n \u003cp\u003e0.741\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 61px;\"\u003e\n \u003cp\u003e0.092\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.832\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.949\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.449\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 63px;\"\u003e\n \u003cp\u003e0.945\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 52px;\"\u003e\n \u003cp\u003e0.057\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 52px;\"\u003e\n \u003cp\u003e0.414\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0.171\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 53px;\"\u003e\n \u003cp\u003ehigh\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 33px;\"\u003e\n \u003cp\u003eCI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 56px;\"\u003e\n \u003cp\u003e0.121\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 61px;\"\u003e\n \u003cp\u003e-0.061\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 57px;\"\u003e\n \u003cp\u003e-0.036\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 57px;\"\u003e\n \u003cp\u003e-0.044\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.088\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 63px;\"\u003e\n \u003cp\u003e-0.014\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 52px;\"\u003e\n \u003cp\u003e0.230\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 52px;\"\u003e\n \u003cp\u003e-0.037\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 51px;\"\u003e\n \u003cp\u003e-0.037\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 33px;\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 56px;\"\u003e\n \u003cp\u003e0.399\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 61px;\"\u003e\n \u003cp\u003e0.669\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.803\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.762\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.544\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 63px;\"\u003e\n \u003cp\u003e0.924\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 52px;\"\u003e\n \u003cp\u003e0.105\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 52px;\"\u003e\n \u003cp\u003e0.799\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0.795\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 53px;\"\u003e\n \u003cp\u003eweight\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 33px;\"\u003e\n \u003cp\u003eCI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 56px;\"\u003e\n \u003cp\u003e0.198\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 61px;\"\u003e\n \u003cp\u003e0.103\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 57px;\"\u003e\n \u003cp\u003e-0.128\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 57px;\"\u003e\n \u003cp\u003e-0.108\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.066\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 63px;\"\u003e\n \u003cp\u003e-0.081\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 52px;\"\u003e\n \u003cp\u003e0.394\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 52px;\"\u003e\n \u003cp\u003e0.056\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0.128\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 33px;\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 56px;\"\u003e\n \u003cp\u003e0.163\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 61px;\"\u003e\n \u003cp\u003e0.471\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.375\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.456\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.651\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 63px;\"\u003e\n \u003cp\u003e0.577\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 52px;\"\u003e\n \u003cp\u003e0.004\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 52px;\"\u003e\n \u003cp\u003e0.696\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0.370\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 53px;\"\u003e\n \u003cp\u003esex\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 33px;\"\u003e\n \u003cp\u003eCI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 56px;\"\u003e\n \u003cp\u003e0.167\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 61px;\"\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.066\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.115\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 59px;\"\u003e\n \u003cp\u003e-0.036\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 63px;\"\u003e\n \u003cp\u003e0.140\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 52px;\"\u003e\n \u003cp\u003e0.036\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 52px;\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0.005\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 33px;\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 56px;\"\u003e\n \u003cp\u003e0.081\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 61px;\"\u003e\n \u003cp\u003e0.992\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.495\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.232\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.712\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 63px;\"\u003e\n \u003cp\u003e0.143\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 52px;\"\u003e\n \u003cp\u003e0.705\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 52px;\"\u003e\n \u003cp\u003e0.999\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0.960\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eTable 3 Correlation between the observation indicators of the Shousanli acupoint and general conditions\u0026nbsp;\u003c/p\u003e\n\u003cdiv align=\"center\"\u003e\n \u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"616\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"10\" style=\"width: 555px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSSL-Correlations\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 61px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 85px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003eSSLvertical\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 62px;\"\u003e\n \u003cp\u003eSSLlevel\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 63px;\"\u003e\n \u003cp\u003eneedletipT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 57px;\"\u003e\n \u003cp\u003edetailedL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 64px;\"\u003e\n \u003cp\u003eneedletipP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003edetailedM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003eCDFI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 61px;\"\u003e\n \u003cp\u003eMEAN11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 61px;\"\u003e\n \u003cp\u003eMEAN12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 55px;\"\u003e\n \u003cp\u003eyear\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30px;\"\u003e\n \u003cp\u003eCI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e-0.022\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e-0.005\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 63px;\"\u003e\n \u003cp\u003e-0.040\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 57px;\"\u003e\n \u003cp\u003e-0.056\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 64px;\"\u003e\n \u003cp\u003e0.087\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e-0.048\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.043\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 61px;\"\u003e\n \u003cp\u003e0.047\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 61px;\"\u003e\n \u003cp\u003e0.075\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30px;\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.822\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.961\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 63px;\"\u003e\n \u003cp\u003e0.675\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.561\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 64px;\"\u003e\n \u003cp\u003e0.369\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.616\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.655\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 61px;\"\u003e\n \u003cp\u003e0.624\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 61px;\"\u003e\n \u003cp\u003e0.436\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 55px;\"\u003e\n \u003cp\u003ehigh\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30px;\"\u003e\n \u003cp\u003eCI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.216\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.092\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 63px;\"\u003e\n \u003cp\u003e-0.022\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 57px;\"\u003e\n \u003cp\u003e-0.043\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 64px;\"\u003e\n \u003cp\u003e-0.005\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e-0.046\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e-0.037\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 61px;\"\u003e\n \u003cp\u003e0.083\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 61px;\"\u003e\n \u003cp\u003e-0.025\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30px;\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.132\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.525\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 63px;\"\u003e\n \u003cp\u003e0.881\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.767\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 64px;\"\u003e\n \u003cp\u003e0.972\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.746\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.796\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 61px;\"\u003e\n \u003cp\u003e0.562\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 61px;\"\u003e\n \u003cp\u003e0.861\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 55px;\"\u003e\n \u003cp\u003eweight\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30px;\"\u003e\n \u003cp\u003eCI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.235\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.123\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 63px;\"\u003e\n \u003cp\u003e-0.049\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 57px;\"\u003e\n \u003cp\u003e-0.209\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 64px;\"\u003e\n \u003cp\u003e-0.135\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e-0.218\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.104\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 61px;\"\u003e\n \u003cp\u003e0.080\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 61px;\"\u003e\n \u003cp\u003e0.086\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30px;\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.394\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 63px;\"\u003e\n \u003cp\u003e0.732\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.140\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 64px;\"\u003e\n \u003cp\u003e0.346\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.124\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.466\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 61px;\"\u003e\n \u003cp\u003e0.577\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 61px;\"\u003e\n \u003cp\u003e0.548\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 55px;\"\u003e\n \u003cp\u003esex\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 30px;\"\u003e\n \u003cp\u003eCI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.097\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.052\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 63px;\"\u003e\n \u003cp\u003e0.061\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.019\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 64px;\"\u003e\n \u003cp\u003e-0.064\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.035\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e-0.102\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 61px;\"\u003e\n \u003cp\u003e-0.011\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 61px;\"\u003e\n \u003cp\u003e-0.034\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 30px;\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.313\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.590\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 63px;\"\u003e\n \u003cp\u003e0.529\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.844\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 64px;\"\u003e\n \u003cp\u003e0.505\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.716\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.285\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 61px;\"\u003e\n \u003cp\u003e0.905\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 61px;\"\u003e\n \u003cp\u003e0.722\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eNote: In Table 1-3: vertical: the vertical distance between the acupoint and the skin; level: the vertical distance between the acupoint and the radius; needletipT, detailedL, needletipP, and detailedM: acupoint positions; CDFI: blood flow status; MEAN: mean elasticity; 11: acupoint point; 12: reference point\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.2 Two-dimensional ultrasound\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.2.1 Measurement values of acupuncture points\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAnalysis showed significant differences in the distribution patterns of deep and superficial muscle layers between the Hegu acupoint and the Xialian/Shousanli acupoints (P \u0026lt; 0.05). In contrast, Xialian and Shousanli acupoints, being anatomically adjacent, exhibited no significant variance in their positional characteristics (P \u0026gt; 0.05) (refer to Table 5 for detailed information). Specifically, the Hegu acupoint was predominantly situated in the adductor pollicis muscle (62.7%), with 29.1% of occurrences in the superficial layer of this muscle. The Xialian acupoint was primarily located in the supinator muscle (41.8%), with 20.9% in the superficial layer of the supinator. The Shousanli acupoint was mainly positioned in the intermuscular fascia (39.1%), while 37.3% of cases lay in the fascia between the extensor carpi radialis longus and the supinator muscle (see Figure 4).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTable 4 Acupuncture point measurement values (cm) \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003cdiv align=\"center\"\u003e\n \u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"608\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 77px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 91px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 91px;\"\u003e\n \u003cp\u003eHGlevel\u003c/p\u003e\n \u003cp\u003e(110)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003eXLlevel\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;(110)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 84px;\"\u003e\n \u003cp\u003eSSLvertical\u003c/p\u003e\n \u003cp\u003e(110)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 89px;\"\u003e\n \u003cp\u003eSSLlevel\u003c/p\u003e\n \u003cp\u003e\u0026nbsp; (110)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 77px;\"\u003e\n \u003cp\u003eM\u003c/p\u003e\n \u003cp\u003e（Q\u003csub\u003e1\u003c/sub\u003e,Q\u003csub\u003e3\u003c/sub\u003e）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 91px;\"\u003e\n \u003cp\u003e1.72\u003c/p\u003e\n \u003cp\u003e（1.38,1.96）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 91px;\"\u003e\n \u003cp\u003e0.93\u003c/p\u003e\n \u003cp\u003e（0.63,1.24）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003e1.64\u003c/p\u003e\n \u003cp\u003e（1.36,1.95）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003e0.43\u003c/p\u003e\n \u003cp\u003e（0.29,0.60）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 84px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 89px;\"\u003e\n \u003cp\u003e0.66\u003c/p\u003e\n \u003cp\u003e（0.45,0.84）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eNote: Vertical refers to the distance between the acupoint and the skin. Level denotes the distance between the acupoint and the radius, with the Hegu acupoint measured from the midpoint of the radius. Q₁represents the first percentile, while \u0026nbsp;Q₃indicates the third percentile. HG stands for Hegu, XL denotes the Xialian acupoint, and SSL refers to the Shousanli acupoint.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.2.2 Muscular Architecture at Acupoint Sites\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eshowed significant differences in the distribution patterns of deep and superficial muscle layers between Hegu acupoint and Xiaolian/Shousanli acupoints (P \u0026lt; 0.05). In contrast, Xiaolian and Shousanli acupoints, being anatomically adjacent, exhibited no significant variance in their positional characteristics (P \u0026gt; 0.05) (refer to Table 5 for detailed information). Specifically, Hegu acupoint was predominantly situated in the adductor pollicis muscle (62.7%), with 29.1% of occurrences in the superficial layer of this muscle. Xiaolian acupoint was primarily located in the supinator muscle (41.8%), with 20.9% in the superficial layer of the supinator. Shousanli acupoint was mainly positioned in the intermuscular fascia (39.1%), while 37.3% of cases were found in the fascia between the extensor carpi radialis longus and the supinator muscle (see Figure 4).\u003c/p\u003e\n\u003cp\u003eTable\u0026nbsp;5\u0026nbsp;:Analysis of the anatomical structure of acupoint locations\u003c/p\u003e\n\u003cdiv align=\"center\"\u003e\n \u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"567\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 93px;\"\u003e\n \u003cp\u003evariables\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003eHG\u003csup\u003e*\u003c/sup\u003e\u003csup\u003e＃\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003eXL\u003csup\u003e*☆\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003eSSL\u003csup\u003e＃\u003c/sup\u003e\u003csup\u003e☆\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003estatistic\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 63px;\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 93px;\"\u003e\n \u003cp\u003eDissect\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003e25.57\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 63px;\"\u003e\n \u003cp\u003e＜0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 93px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e14（\u0026nbsp;12.7）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e29（26.4）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e34（30.9）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 63px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 93px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e69（62.7）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e46（41.8）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e33（30.0）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 63px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 93px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e27（24.5）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e35（33.3）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e43（39.1）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 63px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eNote: 1: Superficial muscles, 2: Deep muscles, 3: Intermuscular fascia; \u003csup\u003e#\u003c/sup\u003e: Comparison of the location characteristics between HG and SSL acupoints, P \u0026lt; 0.001; \u003csup\u003e*\u003c/sup\u003e: Comparison of the location characteristics between HG and XL acupoints, P \u0026lt; 0.004; \u003csup\u003e☆\u003c/sup\u003e: Comparison of the location characteristics between XL and SSL, P \u0026gt; 0.05 (0.187); Most of the Hegu (LI4) acupoints are located in the deep muscles, while the Xialian (LI8) and Shousanli (LI10) acupoints are distributed relatively evenly.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2\u003c/strong\u003e\u003cstrong\u003e.2.3 Correlation between Acupoint Location and Fascia\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eUpon contact between the needle tip and the fascia, subjects reported a distinct \u0026quot;Deqi\u0026quot; sensation, suggesting a strong correlation between acupoint locations and fascial structures.We found statistically significant differences among the three groups concerning the presence of acupoints on fascia (P=0.003). The proportions of acupoints associated with fascia were 50.9% for Hegu (LI4), 68.2% for Xialian (LI8), and 71.8% for Shousanli (LI10) (see Table 6).\u003c/p\u003e\n\u003cp\u003eTable\u0026nbsp;6\u0026nbsp;Analysis of the correlation between acupoints and fascia\u003c/p\u003e\n\u003cdiv align=\"center\"\u003e\n \u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"557\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" style=\"width: 557px;\"\u003e\n \u003cp\u003eComparison\u0026nbsp;of\u0026nbsp;Acupoint\u0026nbsp;Parameter（\u0026nbsp;Fascial/non-fascia）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eVariables\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 160px;\"\u003e\n \u003cp\u003eFascial (n=208 \u0026nbsp;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003enon-fascia(n=122\u0026nbsp;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 83px;\"\u003e\n \u003cp\u003eStatistic\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 72px;\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eLocal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 160px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 83px;\"\u003e\n \u003cp\u003e11.864\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 72px;\"\u003e\n \u003cp\u003e0.003\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eHG\u003csup\u003e+*\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 160px;\"\u003e\n \u003cp\u003e56（50.9）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e54（49.1）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 83px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eXL\u003csup\u003e#*\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 160px;\"\u003e\n \u003cp\u003e75（68.2）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e35（31.8）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 83px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eSSL\u003csup\u003e#+\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 160px;\"\u003e\n \u003cp\u003e79（71.8）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e31（28.2）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 83px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp;Note: Fascial: fascial group; non-fascia: non-fascial group. + indicates the pairwise comparison between HG and SSL, with P \u0026lt; 0.03; * indicates the pairwise comparison between HG and XL, with P \u0026lt; 0.03; # indicates the pairwise comparison between XL and SSL, with P \u0026gt; 0.05.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.3 Shear Wave Elastography (SWE)\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe observed a statistically significant difference in the mean elastic modulus (MEAN) between the acupoint and non-acupoint locations of the Shousanli acupoint (P \u0026lt; 0.05). Specifically, the P values for the Hegu and Xialian acupoints were 0.048 and 0.047, respectively, indicating potential statistical differences between the acupoint sites and their corresponding reference points for both Hegu and Shousanli acupoints. Furthermore, the median elastic modulus value at acupoint sites exceeded that at reference points (see Table 7).\u003c/p\u003e\n\u003cp\u003eTable 7 Comparison of elastic mean values between acupoints and reference points\u0026nbsp;\u003c/p\u003e\n\u003cdiv align=\"center\"\u003e\n \u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"568\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 108px;\"\u003e\n \u003cp\u003eVariables\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 124px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 147px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 111px;\"\u003e\n \u003cp\u003eStatistic\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 108px;\"\u003e\n \u003cp\u003eHG\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 124px;\"\u003e\n \u003cp\u003e2.76\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(2.20，3.29)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 147px;\"\u003e\n \u003cp\u003e2.66\u003c/p\u003e\n \u003cp\u003e(2.06，3.30)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 111px;\"\u003e\n \u003cp\u003e6.038\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e0.048\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 108px;\"\u003e\n \u003cp\u003eXL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 124px;\"\u003e\n \u003cp\u003e2.86\u003c/p\u003e\n \u003cp\u003e(2.25，3.49)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 147px;\"\u003e\n \u003cp\u003e2.79\u003c/p\u003e\n \u003cp\u003e(2.17，3.32）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 111px;\"\u003e\n \u003cp\u003e6.030\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e0.047\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 108px;\"\u003e\n \u003cp\u003eSSL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 124px;\"\u003e\n \u003cp\u003e2.83\u003c/p\u003e\n \u003cp\u003e(2.36，3.36)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 147px;\"\u003e\n \u003cp\u003e2.69\u003c/p\u003e\n \u003cp\u003e(2.19，3.16)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 111px;\"\u003e\n \u003cp\u003e6.797\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e0.033\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eNote: 1: Acupoint, 2: Reference point\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.4. Color Doppler Flow Imaging\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAccording to Adler\u0026rsquo;s grading of blood flow signals in Color Doppler Flow Imaging, the acupoint sites were primarily marked by a lack of discernible blood flow signals. Pairwise comparisons of blood flow signal distribution among the acupoints showed no statistically significant differences (P \u0026gt; 0.05) (see Table 8).\u003c/p\u003e\n\u003cp\u003eTable\u0026nbsp;8:Color flow grading of acupoints\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"527\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" style=\"width: 110px;\"\u003e\n \u003cp\u003eAdler\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 88px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 95px;\"\u003e\n \u003cp\u003eI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 86px;\"\u003e\n \u003cp\u003eII\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 77px;\"\u003e\n \u003cp\u003estatistic\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" style=\"width: 110px;\"\u003e\n \u003cp\u003eacupoint\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 88px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 86px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 77px;\"\u003e\n \u003cp\u003e1.65\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 70px;\"\u003e\n \u003cp\u003e0.438\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" style=\"width: 110px;\"\u003e\n \u003cp\u003eHG\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 88px;\"\u003e\n \u003cp\u003e97(88.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 95px;\"\u003e\n \u003cp\u003e10(9.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 86px;\"\u003e\n \u003cp\u003e3(2.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 77px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 70px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" style=\"width: 110px;\"\u003e\n \u003cp\u003eXL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 88px;\"\u003e\n \u003cp\u003e103(92.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 95px;\"\u003e\n \u003cp\u003e7(6.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 86px;\"\u003e\n \u003cp\u003e1(0.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 77px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 70px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" style=\"width: 110px;\"\u003e\n \u003cp\u003eSSL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 88px;\"\u003e\n \u003cp\u003e98(89.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 95px;\"\u003e\n \u003cp\u003e11(10.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 86px;\"\u003e\n \u003cp\u003e1(0.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 77px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" style=\"width: 70px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eNote: \u0026chi;\u0026sup2;: Chi-square test, 0: no obvious blood flow, I: a small amount (punctate) of blood flow, II: a moderate amount (rod-shaped) of blood flow\u003c/p\u003e"},{"header":" Discussion","content":"\u003cp\u003eUltrasound imaging is distinguished by its real-time dynamic and multimodal capabilities. In recent years, its application in research on meridians and acupoints has grown, revealing promising prospects. This study enrolled a relatively large cohort of healthy participants and utilized multimodal ultrasound techniques to investigate acupoints along the Hand Yangming Meridian. We identified the sonographic characteristics of these acupoints, thereby partially elucidating the relationship between meridian acupoints and anatomical structures, as well as the biomechanical effects of acupuncture.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3\u003c/strong\u003e\u003cstrong\u003e.1\u003c/strong\u003e\u003cstrong\u003eGrayscale Ultrasound\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eMeasurements at the acupoints demonstrated relatively fixed locations, exhibiting stability despite potential influencing factors, with values clustering around the median.We found no significant correlation between these measurements and general characteristics such as age, sex, or body fat percentage.This finding challenges the traditional belief that the effects of acupuncture depend on individualized sensations; instead, it implies a connection between acupoint locations and specific tissue structures(17).\u003c/p\u003e\n\u003cp\u003eFurther analysis revealed that the three acupoints were primarily situated within muscles: Hegu (LI4) in the adductor pollicis, Xialian (LI8) in the supinator muscle, and Shousanli (LI10) in the intermuscular fascia. Hegu notably had more deep muscle locations compared to Xialian and Shousanli, where the proportion of intermuscular locations increased. This distribution aligns with the local anatomical environment of each acupoint, suggesting that acupoints\u0026apos; functional specificity may derive from their underlying structural foundation.\u003c/p\u003e\n\u003cp\u003eUsing high-frequency ultrasound imaging, we consistently observed a strong correlation between acupoints and fascia, particularly intermuscular septa and perimysium.\u0026nbsp;Subjects were more prone to experiencing the \u0026quot;Deqi\u0026quot; sensation when the acupuncture needle tip made contact with the fascia. It is important to acknowledge that fascia visualization on ultrasound may not be definitive; acupoints categorized as non-fascia may still be situated on delicate fascial structures. Furthermore, an analysis comparing the fascial compositions of three acupoints indicated a progressive increase in fascial association for acupoints located closer to the meridian origin. This observation aligns with traditional meridian theory and supports the fasciology concept that\u0026nbsp;\u0026quot;meridian pathways align with the fascial network distribution\u0026quot;(18-20)\u0026nbsp;.\u003c/p\u003e\n\u003cp\u003eFascia, as a continuous three-dimensional connective tissue network, not only provides structural support for acupoints but also may engage in local signal transduction and regulatory functions through the nerve endings, capillaries, and immune cells embedded within it (21, 22), Thus, fascia plays a crucial role in eliciting \u0026ldquo;Deqi\u0026rdquo; and generating therapeutic effects during acupuncture. We assert that fascial structures occupy a significant position within the framework of meridian acupoints, although the overlap is not entirely comprehensive. While the pathways of meridian acupoints correlate with fascia, the extent of this correlation varies among different meridian segments. Notably, the degree of overlap with fascia tends to increase progressively when moving proximally along the meridian. This observation provides new insights and directions for research on ultrasound and meridians(23-25) .\u003c/p\u003e\n\u003cp\u003eUltrasound facilitates precise visualization of \u0026ldquo;Deqi\u0026rdquo; locations, aiding in identifying the primary nerves innervating the acupoint region. In this study, needle manipulation sites and the sensation of \u0026ldquo;Deqi\u0026rdquo; were consistently located within the innervation territory of the deep branch of the ulnar nerve. This discovery offers valuable insights for investigating the neuromodulation mechanisms of acupuncture in clinical practice.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.2. Color Doppler Flow Imaging\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAcupoints are located within the superficial soft tissues. High-frequency color Doppler ultrasound typically demonstrates hypovascularity, with blood flow grading primarily ranging from 0 to 1. Although previous studies have indicated that acupuncture therapy can induce alterations in local microcirculation(26-28) , the present study found no significant differences in color blood flow signals among various acupoints or between acupoints and reference points. This lack of difference may be due to the sensitivity limitations of the blood flow detection technology we utilised. In addition to color Doppler, ultrasonic assessment of local blood flow encompasses techniques such as Superb Microvascular Imaging (SMI) and Contrast-Enhanced Ultrasound (CEUS). CEUS, in particular, offers distinct advantages for detecting local circulation. However, the use of CEUS was clearly constrained by ethical considerations, given that the study subjects were healthy volunteers(29, 30). Our team is currently undertaking further in-depth investigations using alternative experimental approaches.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.3. Shear Wave Elastography\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn this study, we quantitatively compared Young\u0026apos;s modulus between acupoint and non-acupoint regions using shear wave elastography. The results indicated that the elastic values at the acupoint sites were significantly higher than those at the reference points located 0.5 cm away horizontally for all three acupoints. Numerous researchers propose that needling acupoints may trigger the discharge of fine nerves in the area, resulting in soft tissue contraction and an associated increase in Young\u0026rsquo;s modulus values. This phenomenon is reflected in elastography as a characteristic increase in stiffness at the center, accompanied by a centrifugal decrease(31) .At the same time, this difference may also stem from the denser fascial tissue within the acupoint region , a higher density of nerve endings and microvascular networks , as well as the inherent specificity of the mechanical properties of the tissues in this area(31). Elastography thus offers a potential quantitative imaging biomarker for the objective identification of acupoints and further substantiates the distinguishability of acupoints in terms of tissue texture.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eLimitations\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe present study serves as a preliminary exploration of in vivo acupoint observation through multimodal ultrasound technology and is subject to certain limitations. For example, the potential of color Doppler detection techniques necessitates further investigation. Additionally, this study did not examine acupoints under varying conditions, nor did it incorporate a disease group for comparative analysis. These limitations highlight important avenues for future research.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eAcupoints located on the Hand Yangming Meridian display distinct sonographic characteristics and stable anatomical positions. They exhibit a close association with fascia, adhere to a consistent pattern along the proximal trajectory of the meridian, and possess unique mechanical properties as demonstrated by elastography. This study establishes a method for the visualization and quantitative assessment of acupoints based on ultrasound features, thereby providing imaging and biomechanical support for the \"meridian-connective tissue\" hypothesis. Moreover, these findings lay a new methodological foundation for investigating the mechanisms of acupuncture and for the integration of traditional Chinese and Western medicine.\u003c/p\u003e\n"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eLiu Fangqin\u0026nbsp;and\u0026nbsp;Luo Yunhao: Co-first authors. They contributed equally to the study design, coordinated data acquisition, performed statistical analysis, and drafted the manuscript.Yan Jiaojun and\u0026nbsp;Wang Zhengyan: Contributed to participant recruitment, ultrasonographic data acquisition, and critical revision of the manuscript.Wu Shiping, Li Shuting, Nan Xuhong, Cheng Chunxia, Fu Xuerong, Lu Yaling, Xia Xuemei, Du Huan, and Fan Zhengchao: Contributed to participant recruitment, ultrasonographic examination, and data collection at their respective centres.Qiao Lang: Corresponding author. He conceived and supervised the study, secured funding, coordinated the multicentre collaboration, and critically revised the manuscript. Dr. Qiao serves as the guarantor of the work, taking full responsibility for the integrity of the data and the accuracy of the data analysis.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis work was supported by The project on Sichuan Provincial Natural Science Foundation-Research on AI Recognition of Acupoints on the Hand-Yangming Meridian and Specificity of Acupoint Effects Based on Ultrasound Multimodal Technology（under Grant No. 2024NSFSC0725）\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTrial registration\u003c/strong\u003e\u003cstrong\u003e:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe research was registered with the International Traditional Medicine Clinical Trial Registry (ITMCTR2026000042). This study has adhered to the Declaration of Helsinki. Free and informed consent was obtained from all the participants.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthical approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eEthical approval was sought from the Ethics Committee of Sichuan Hospital of Integrated Traditional Chinese and Western Medicine approved this study (Approval No. KY-2023-010).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eMatos LC, Machado JP, Monteiro FJ, Greten HJ. Understanding Traditional Chinese Medicine Therapeutics: An Overview of the Basics and Clinical Applications. 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Clin Anat. 2024;37(7):701-9.\u003c/li\u003e\n \u003cli\u003eLi F, He T, Xu Q, Lin LT, Li H, Liu Y, et al. What is the Acupoint? A preliminary review of Acupoints. Pain Medicine. 2015;16(10):1905-15.\u003c/li\u003e\n \u003cli\u003eLi JH, Fei ZN, Xie YJ, Deng D, Ming XC, Niu F. A review of acupoint localization based on deep learning. Chinese Medicine. 2025;20(1).\u003c/li\u003e\n \u003cli\u003eChen YW, Li MZ, Guo KX. Exploring the mechanisms and current status of acupuncture in alleviating tumor metabolism and associated diseases: Insights from the central nervous system and immune microenvironment. SLAS Technol. 2024;29(6):17.\u003c/li\u003e\n \u003cli\u003eLiu S, Wang Z, Su Y, Qi L, Yang W, Fu M, et al. A neuroanatomical basis for electroacupuncture to drive the vagal-adrenal axis. Nature. 2021;598(7882):641-5.\u003c/li\u003e\n \u003cli\u003eFan Z, Dou B, Wang J, Wu Y, Du S, Li J, et al. Effects and mechanisms of acupuncture analgesia mediated by afferent nerves in acupoint microenvironments. Front Neurosci. 2023;17:1239839.\u003c/li\u003e\n \u003cli\u003eLangevin HM. Acupuncture, connective tissue, and peripheral sensory modulation. Crit Rev Eukaryot Gene Expr. 2014;24(3):249-53.\u003c/li\u003e\n \u003cli\u003eIntriago V, Reina MA, Boezaart AP, Tubbs RS, Monta\u0026ntilde;a AV, P\u0026eacute;rez-Rodr\u0026iacute;guez FJ, et al. Microscopy of structures surrounding typical acupoints used in clinical practice and electron microscopic evaluation of acupuncture needles. Clin Anat. 2022;35(3):392-403.\u003c/li\u003e\n \u003cli\u003eChoi KH, Cho SJ, Kim M, Kwon OS, Kang SY, Seo SY, et al. What is the analgesic range of acupuncture stimulus for treating acute pain? Front Hum Neurosci. 2023;17:1281832.\u003c/li\u003e\n \u003cli\u003eMa SX. 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Acupunct Med. 2020;38(2):86-92.\u003c/li\u003e\n \u003cli\u003eSandberg M, Lundeberg T, Lindberg LG, Gerdle B. Effects of acupuncture on skin and muscle blood flow in healthy subjects. Eur J Appl Physiol. 2003;90(1-2):114-9.\u003c/li\u003e\n \u003cli\u003eHan R, Hu J. Acupuncture: An Overview on Its Functions, Meridian Pathways and Molecular Mechanisms. Am J Chin Med. 2024;52(5):1215-44.\u003c/li\u003e\n \u003cli\u003eLu L, Chen X, Gong H, Cai Z, Luo T, He P, et al. A Comparative Study of Sononeoperfusion Effects Induced by Diagnostic and Therapeutic Ultrasound-Stimulated Microbubbles. J Ultrasound Med. 2025.\u003c/li\u003e\n \u003cli\u003evan Elburg B, Bruil K, Lajoinie G, Borden M, Versluis M, Segers T. Tuning the Shell Elasticity of Phospholipid-Coated Microbubbles via Palmitic Acid Doping. Langmuir. 2025;41(42):28313-21.\u003c/li\u003e\n \u003cli\u003eYunshan L, Chengli X, Peiming Z, Haocheng Q, Xudong L, Liming L. Integrative research on the mechanisms of acupuncture mechanics and interdisciplinary innovation. Biomedical Engineering Online. 2025;24(1).\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Hegu acupoint, Xia lian acupoint, Shousanli acupoint, Ultrasonic imaging, Ultrasonic characteristics of acupoints","lastPublishedDoi":"10.21203/rs.3.rs-8778712/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8778712/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eObjective: \u003c/strong\u003eIn vivo evidence defining the anatomical basis of acupoints remains limited. We characterized the ultrasonographic features of three Hand Yangming Meridian acupoints and analyzed influencing factors.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods: \u003c/strong\u003eThis multicenter cross-sectional study included 110 healthy volunteers aged 18–65 without upper limb pathology, excluding pregnant individuals or those with coagulopathy. We inserted needles at LI4, LI8, and LI10 to elicit Deqi and measured depth, tissue structure, and elastic modulus using multimodal ultrasound versus a 5 mm reference point.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003eWe included 110 healthy volunteers. Measurements showed median vertical distances from the Hegu (LI4), Xialian (LI8), and Shousanli (LI10) acupoints to the skin and radial surface were 1.72 (1.38, 1.96) cm and 0.93 (0.63, 1.24)cm, 1.64 (1.36, 1.95)cm and 0.43 (0.29, 0.60)cm, and 1.64 (1.36, 1.95)cm and 0.43 (0.29, 0.60)cm, respectively. These values showed no correlation with height, weight, age, or sex (p \u0026gt; 0.05). Acupoints localized predominantly within specific musculo-fascial structures: LI4 in the adductor pollicis (62.7%), LI8 in the supinator (41.8%), and LI10 in the fascia between the extensor carpi radialis longus and supinator (39.1%). This significant association with fascial structures (all P \u0026lt; 0.05) increased progressively along the meridian. Additionally, the mean elastic modulus at acupoints was significantly higher than at reference points (all P \u0026lt; 0.05).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions: \u003c/strong\u003eWe identified stable ultrasonographic features within specific myofascial structures for these acupoints. These results support the meridian-connective tissue hypothesis and offer new methodological pathways for acupuncture research.\u003c/p\u003e","manuscriptTitle":"Multicenter Sudy on Ultrasound Characteristics of Acupoints in the Hand Yangming Meridia n and Related Factors","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-04-30 07:31:48","doi":"10.21203/rs.3.rs-8778712/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"a354bf04-1ce4-4fa1-a9dc-14aa26a03844","owner":[],"postedDate":"April 30th, 2026","published":true,"recentEditorialEvents":[{"type":"decision","content":"Rejected","date":"2026-05-13T15:01:36+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-05-06T08:28:12+00:00","index":22,"fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-05-05T04:57:50+00:00","index":21,"fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-05-13T15:28:16+00:00","versionOfRecord":[],"versionCreatedAt":"2026-04-30 07:31:48","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8778712","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8778712","identity":"rs-8778712","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}