基于JACK的驾驶姿势的下肢关节受力及舒适度分析

目的 研究驾驶姿势下外力施加给人体下肢时,关节角度及外力大小对关节力矩大小的影响特征;根据力矩计算单关节舒适度并验证。方法 采集人体测量参数,在Jack中建立了10名志愿者对应的个性化数字人模型。模拟人的驾驶姿势,计算下肢各关节处的力矩大小。结果 Jack计算出关节力矩与角度和外力的相关性明显,变化趋势与实测结果一致。舒适度评价方法反映出真实关节感受。结论 各关节力矩与踝关节角度呈负相关,与外力呈正相关;驾驶员的膝关节角度取108°到113°度为宜;对于髋关节和踝关节力矩,外力的影响最大;对于膝关节力矩,膝关节角度的影响最大;关节力矩受踝关节角度的影响最小,与之负相关;基于力矩的舒适度概念定量地反映出关节舒适感,可以为驾驶环境设计提供参考。     

Relative motion between the flexor digitorum superficialis tendon and paratenon in zone V increases with wrist flexion angle

Carpal tunnel syndrome is characterized by non‐inflammatory fibrosis of the subsynovial connective tissue (SSCT), a paratenon‐like structure inside the carpal tunnel. This pathology suggests repetitive and/or excessive shear forces are involved in injury development. We assessed relative motion between the flexor digitorum superficialis (FDS) tendon and adjacent paratenon in Zone V using colour Doppler imaging as 16 healthy participants completed three long finger movements (metacarpophalangeal joint flexion, proximal and distal interphalangeal joint flexion, full finger flexion) in three wrist postures (30° extension, 0°, 30° flexion). While the type of finger movement did not affect tendon‐paratenon relative motion, we found a significant main effect of wrist posture (p < 0.001). Relative displacement between the FDS tendon and paratenon (as a percentage of tendon displacement) increased from 27.2% (95%CI = 24.8–29.5%) in 30° wrist extension to 39.9% (95%CI = 37.3–42.4%) in 30° wrist flexion. Optical motion capture confirmed that wrist posture did not affect metacarpophalangeal joint range of motion (p = 0.265) or proximal interphalangeal joint range of motion (p = 0.582). These results indicate that relative motion increased due to paratenon strain when the wrist was flexed. While our findings agree with previous cadaveric research in wrist flexion, we found that relative displacement decreased in 30° wrist extension (compared to 0°). These results differ from cadaveric research, possibly due to challenges maintaining anatomic fidelity of the viscoelastic paratenon tissue in vitro. Overall, our study suggests a greater susceptibility to shear injury during repetitive finger movements, particularly when the wrist is flexed. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1248–1255, 2016.     

Thermal asymmetry of the human scrotum

BACKGROUND: Scrotal temperatures in men have been reported to be either similar on both sides or higher on the left than the right scrotum. We aimed to clarify this discrepancy from new data. METHODS: Retrospective analyses of scrotal temperatures in men aged 20-52 years measured every 2 min with probes connected to a data collector in three experiments. In Experiment I, eight men have been submitted to four successive body positions for 15 min each, first naked then clothed. Experiment II involved 11 postal employees working in a standing position for 90 min continuously. Experiment III involved 11 bus drivers and a 90 min period of continuous driving. Outcome parameters were left and right scrotal temperatures. RESULTS: In Experiment I, mean values and kinetics of scrotal temperature differed significantly in the naked and clothed state. In all three experiments, left scrotal temperature in the clothed state was higher than right scrotal temperature in terms of mean values and temperature kinetics. CONCLUSIONS: Lack of thermal symmetry was seen in the right and left scrotum, whether naked or clothed, and this applied regardless of position or activity when clothed. This thermal difference between right and left scrotum could contribute to the asymmetry in the male external genital organs.     

Prevalence of musculoskeletal disorders among Indian railway sahayaks

Railway sahayak or also known as coolie is one of the oldest occupations in India. This occupational group is continuously subjected to various musculoskeletal problems due to repetitive load exertion in unnatural postures. The present research aims to examine the prevalence of musculoskeletal disorders (MSDs) among Indian railway sahayaks. A cross-sectional study has been conducted on a sample of 51 male sahayaks. With a modified Nordic questionnaire, data were collected on their demographics, work, and musculoskeletal pain history. Electromyography (EMG) of the upper trapezius muscle of selected 12 healthy sahayaks having no history of neck–shoulder complaints were analyzed under different load lifting and carrying conditions. Additionally, ergonomic risk levels were recorded using Rapid Entire Body Assessment method. The questionnaire revealed that for the past 1 year prevalence, the most affected body regions of railway sahayaks were neck (47%), shoulder (51%), lower back (43%), and knee (47%). The association between age group and MSDs in different body regions were found significant (p = 0.012 for neck, p = 0.017 for shoulder, etc.). Work experience also had a significant relation to the MSDs in different body regions (p = 0.013 for shoulder,p = 0.023 for calf, etc.). Analysis of variance reveals high significance level between EMG values and tasks performed by the sahayaks. In conclusion, railway sahayaks were found to have high rate of MSDs which may be associated with lifting/carrying heavy loads in awkward postures. Ergonomic interventions must be implemented to reduce the risk level on this group of workers.     

The impact of a change in work posture from seated to stand‐up on work‐related musculoskeletal disorders among sewing‐machine operators

Background

Work‐related postural change could lead to improved musculoskeletal health.

Method(s)

In a quantitative, retrospective, longitudinal study, data of work‐related musculoskeletal disorders of 123 sewing‐machine operators were captured for 4.5 years, and analysed using Poisson regression.

Results

Stand‐up work posture (SUWP) reduced the incidence for spinal disorders (SD) to 0.29 fold the incidence for sitting work posture (SWP) (P < 0.001). Morbid obesity had significantly increased (P = 0.04) incidence of upper limb disorders (ULD), 3.35 times that of normal body mass index (BMI) (regardless of work posture). SUWP was associated with increased IRR (1.49) for lower limb disorders (LLD). LLDs were associated with obesity (overweight (IRR = 2.58; P = 0.08), obese (IRR = 2.45; P = 0.09), and morbidly obese (IRR = 6.24; P = 0.001)).

Conclusions

The protective benefit of the SUWP was statistically significant for SD incidence. Owing to high mean BMI, SUWP had a negative impact on the incidence of LLDs for the first 2 months.

     

姿势解密技术治疗持续性生殖器官兴奋紊乱/生殖器官-骨盆感觉障碍综合征一例并文献复习

持续性生殖器官兴奋紊乱/生殖器官-骨盆感觉障碍综合征（PGAD/GPD）为持续性生殖器官兴奋紊乱（PGAD）和生殖器官-骨盆感觉障碍（GPD）的合称,是国外近年发现的一种以自发或继发出现的持续性性兴奋状态以及生殖器官和骨盆区域的感觉异常为特征的独特病症,但在国内中国知网、万方数据知识服务平台、维普网尚未查到PGAD/GPD的相关报道。姿势解密技术（DPS）是在融合国际上各种主流姿势矫正技术基础上发展出来的以4R原则为核心的手法治疗技术,对改善肌骨疼痛和体态异常等病症疗效独特。本文报道了国内1例运用DPS治疗PGAD/GPD症状完全缓解的病例,并复习国外关于PGAD/GPD的相关文献,以期引起国内同行对此病的关注。     

不同浓度及容量罗哌卡因髋关节囊周围神经阻滞用于髋部骨折老年患者镇痛效果的比较

目的 比较不同浓度及容量罗哌卡因髋关节囊周围神经（PENG）阻滞用于髋部骨折老年患者体位变动时的镇痛效果。
方法 选择腰麻下行髋部骨折手术患者180例,男82例,女98例,年龄65～85岁,BMI 18～28 kg/m²,ASA Ⅱ或Ⅲ级。采用随机数字表法将患者分为六组：0.45%罗哌卡因20 ml组（A1组）、0.45%罗哌卡因10 ml组（B1组）、0.45%罗哌卡因5 ml组（C1组）、0.25%罗哌卡因20 ml组（A2组）、0.25%罗哌卡因10 ml组（B2组）和0.25%罗哌卡因5 ml组（C2组）,每组30例。所有患者均在腰麻前按照上述剂量行超声引导下术侧PENG阻滞。记录神经阻滞前、神经阻滞后5、10 min时静息和活动时NRS评分,记录腰麻摆体位时活动时NRS评分。记录术后当天及第1天股四头肌肌力分级和局麻药中毒、神经损伤、血肿形成等不良反应的发生情况。
结果 神经阻滞前六组静息和活动时NRS评分差异无统计学意义。与神经阻滞前比较,神经阻滞后5 min、10 min时A1组、B1组、C1组、A2组和B2组静息和活动时NRS评分均明显降低（P＜0.05）,神经阻滞后10 min C2组静息和活动时NRS评分明显降低（P<0.05）。与神经阻滞后5 min比较,神经阻滞后10 min C2组静息时NRS评分明显降低（P<0.05）。与神经阻滞后10 min比较,腰麻摆体位时C1组、C2组活动时NRS评分明显升高（P<0.05）。与C1组比较,神经阻滞后5 min、10 min、腰麻摆体位时A1组、B1组活动时NRS评分明显降低（P<0.05）,神经阻滞后10 min,腰麻摆体位时C2组活动时NRS评分明显升高（P<0.05）。与C2组比较,神经阻滞后5 min、10 min、腰麻摆体时A2组、B2静息和活动时NRS评分均明显降低（P<0.05）。术后当天B2组股四头肌肌力完5级例数明显多于A1组、A2组和B1组（P<0.05）。六组均无局麻药中毒、神经损伤、血肿形成等不良反应发生。
结论 超声引导下PENG阻滞对髋部骨折患者麻醉前体位变动有良好的镇痛效果,0.25%罗哌卡因10 ml可提供良好镇痛的效果,对股四头肌肌力影响更小,且不增加不良反应。     

姿态与肌电融合的脑卒中患者上肢运动功能实时评估方法

摘要 目的：提出了一种基于运动姿态与肌电融合的脑卒中患者上肢运动功能实时评估方法。 方法：选取一定数量处于不同Brunnstrom分期的脑卒中患者。首先运用姿态与肌电检测传感器,分别采集康复动作评估过程中不同分期患者上肢运动姿态与表面肌电数据;其次分别提取患肢运动姿态与表面肌电数据特征,在融合姿态与肌电特征信息基础上获取患者上肢运动功能评估数据集;最后,选取具有较好实时分类性能的模糊支持向量机作为分类器,运用评估数据集测试上肢运动功能评估效果。 结果：基于模糊支持向量机构建的运动功能分类器经过离线训练后,姿态与肌电融合的分类器对脑卒中患者上肢运动功能实时评估准确率平均达到83%,且较单纯基于运动姿态(75%)或肌电(74%),具有更好的评估效果。 结论：姿态与肌电融合的上肢运动功能实时评估方法,能较准确地对脑卒中患者上肢运动功能进行实时Brunstrom分期。