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21.
We prospectively analysed the outcome after botulinum injection in patients who did not recover after conservative measures to manage masticatory myofascial pain, and who were not willing to take low dose tricyclic antidepressants as a muscle relaxant. We prospectively 62 patients were assessed with visual analogue scores (VAS) for pain on the affected side before, and 6 weeks after botulinum injection(s) (50 units Dysport® in up to 3 sites), and measured mouth opening in mm. Of those treated 49 (79%) showed at least some improvement (pain reduced by more than 25%). Patients reported more than a 90% reduction in the VAS for 25 (30%) of the 84 sides of the face treated. Only 22 of the 62 patients had more than one course of treatment to the same side. Interincisal distance improved by a mean/median of 0.9 mm (p < 0.03) after treatment. Side effects included 3 cases of temporary weakness of a facial muscle. Ranking the VAS pain scores using the Wilcoxon test before and after injection showed a significant reduction in pain (median change −29.5, interquartile range −53 to −16, p < 0.0001). The treatment significantly improved patients’ pain scores and the overall mean/median reduction in pain was 57%. Botulinum injection does not guarantee complete resolution of myofascial pain, but it usually has some beneficial effect in improving the symptoms, and should be considered as an alternate treatment for masticatory myofascial pain if conservative methods have failed.  相似文献   
22.
目的 探讨杆状体肌病患者临床与病理特点.方法 采用肌肉酶组织化学染色方法和电镜技术观察12例杆状体肌病患者病理特点,收集临床资料进行归纳分析.结果 在本组12例杆状体肌病患者中,7例为先天轻症型,表现为下肢或四肢无力起病,病程进展缓慢,呈良性过程;3例为儿童起病型,均表现为下肢无力,病程持续加重,有肌萎缩现象;2例为成人起病型,双下肢无力起病,累及上肢肌和延髓部肌肉,进展较快,肌萎缩明显,1例出现呼吸困难.部分病例出现狭长面容、双侧弓形足等发育畸形,血清肌酸激酶值正常或稍高,肌电图提示为肌源性损害.在所有患者的肌肉病理切片中,有半数以上肌纤维均出现成堆的杆状体结构;Ⅰ型纤维占优势并呈萎缩现象,且杆状体均出现在Ⅰ型纤维中;改良Gomori染色时杆状体结构最清楚;电镜观察到部分肌原纤维发育不良,如肌丝断裂,排列不整和肌原纤维粗细不一,肌原纤维Z线细小、不规则或消肖失;大量电子密度高的杆状体结构主要出现在肌膜下的肌核周围,少数在肌纤维中央;高倍电镜观察到杆状体结构实际上是肌原纤维中的一段,只是密度很高,但也可是一块无结构的高电子密度体.结论 本组具有3个类型,成人型病情较重,半数以上肌纤维出现杆状体成堆是诊断的关键,电镜有助于确诊.  相似文献   
23.
目的:从力学角度应用试验与仿真相结合对肛管直肠环进行有效预测评估与量化评判。方法:提取直肠癌术后组织标本获得肛管直肠环样本,进行静态拉伸试验,获得肛管直肠环肌群的应力-应变曲线;采用逆向工程的方法将使用MR扫描得到的盆底肛提肌、肛门扩约肌复合体转换为可导入仿真软件的三维几何模型;再使用ABAQUS有限元仿真软件进行仿真分析,模拟肛管直肠环肌群在不同排便条件下所承受的应力情况。结果:采用不同直径的圆柱作用于肛管直肠环,可以有效地模仿人静息状态、强忍状态,力排初状态以及增大腹压的各种活动状态如喷嚏、咳嗽、负重活动。结论:肛管直肠环有限元模型的建立为有效地模拟肛门不同手术方式导致的肛门控便功能障碍研究提供了有效真实的平台。  相似文献   
24.
OBJECTIVES: To validate self-reported preclinical mobility limitation concept and self-report assessment method against muscle power and walking speed, and to study the predictive validity of preclinical mobility limitation with respect to future risk of manifest mobility limitation. DESIGN: Observational prospective cohort study and cross-sectional analysis. SETTING: Research laboratory and community. PARTICIPANTS: A total of 632 community-living (age range, 75-81 y) women and men took part in the baseline assessments and 302 persons in the semi-annual interviews on mobility limitation over 2 years. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Walking speed, muscle power, and self-reported preclinical and manifest mobility limitation. Preclinical mobility limitation was defined as self-reported tiredness or modification of task performance without task difficulty. At baseline, 4 subgroups were created according to self-reported preclinical mobility limitation in any of 3 mobility tasks (walking 2 km, walking 0.5 km, climbing up stairs): no limitation, preclinical limitation, and minor and major manifest limitation. RESULTS: At baseline, participants with preclinical mobility limitation showed intermediate levels of walking speed and muscle power, compared with those with no limitation or manifest mobility limitation. Participants reporting baseline preclinical mobility limitation had 3- to 6-fold higher age- and sex-adjusted risk of progressing to major manifest mobility limitation during the 2-year follow-up compared with participants with no limitation at baseline, whereas the risk among those with minor limitation at baseline was 14- to 18-fold higher compared with those with no limitation. CONCLUSIONS: The self-report assessment tool proved to be a valid measure to capture the early signs of disability and may serve as an inexpensive tool for identifying those nondisabled persons at high risk for future disability.  相似文献   
25.
目的探讨前臂旋前旋后运动的肌力变化以及肱骨应力、位移的生物力学特性。 方法根据Dicom数据在MIMICS中重建三维肱骨并在Hypermesh中划分网格和材料赋值。采用志愿者的身高、体重数据在AnyBody骨骼肌肉系统中建立个性化上肢的骨骼肌肉模型,模拟前臂旋前旋后运动,导出旋前旋后运动过程中的肌力等边界条件,将此数据作为肱骨有限元分析的边界条件。最后在Abauqus中行肱骨应力、位移大小的分析。 结果前臂0°~90°旋前运动时主要是旋前圆肌、旋前方肌发挥作用,旋前圆肌约90°时肌肉力最大,旋前方肌约40°时肌肉力最大。当前臂0°~90°旋后运动时主要是旋后肌、肱二头肌发挥作用,二者肌肉力在旋后约90°时最大。旋前运动约90°时肱骨受到的应力、位移最大,而旋后运动约10°时肱骨受到的应力、位移最大。应力大致在肱骨中下1/3处集中,而位移集中在肱骨的中部及远端,且以肱骨远端最为明显。 结论利用AnyBody骨骼肌肉系统成功模拟了前臂旋前旋后运动并与有限元分析联动,在肌力加载下分析肱骨应力、位移。肱骨中下段是骨折的好发部位。  相似文献   
26.
27.
ObjectiveThe purpose of this study was to compare static maximal back extensor muscle force, endurance, and characteristics of flexion relaxation phenomenon (FRP) in older women with and without age-related hyperkyphosis.MethodsMaximum back extensor force and endurance measured in a sitting position with a designed load cell setup; appearance, onset, and offset angles of FRP; and extension relaxation ratio (ERR) during a dynamic flexion-extension task were compared between 24 older women with hyperkyphosis (thoracic kyphosis angle ≥50°), mean age 65 ± 4.4 years, and 24 older women without hyperkyphosis (thoracic kyphosis angle ?50°), mean age 63 ± 4.3 years. Variables of force, endurance, angles of FRP, and ERR were analyzed using an independent sample t test. A χ2 test was used to identify differences between groups in FRP appearance.ResultsStatic back extensor force and endurance were significantly lower among those with versus those without hyperkyphosis (P ? .001). Although the 2 groups did not differ in FRP appearance and ERR in the superficial erector spinal muscles (P ? .05), FRP in the hyperkyphosis group started sooner and ended later than in the group without hyperkyphosis (P ? .05).ConclusionOur study indicates that women with age-related hyperkyphosis had decreased static maximal force and endurance of the back extensor muscles and prolonged myoelectrical silence of the superficial erector spinal muscles. Reduced endurance of the superficial erector spinal muscles may trigger early onset of FRP and prolonged relaxation of these muscles.  相似文献   
28.
ObjectiveThe objective of the study was to assess the influence of forward head posture on the mechanical parameters and pressure pain threshold of superficial neck muscles in clinically nonsymptomatic individuals with sedentary jobs.MethodsTwenty-five office workers with forward head posture and 25 office workers with normal head posture were matched for sex, age, body mass index, and the nature and duration of their work and were compared at a single point. The study participants were divided into study groups on the basis of photometric craniovertebral angle measurements. The upper trapezius, sternocleidomastoid, and splenius capitis mechanical properties were assessed in the sitting position. Primary outcome measures were muscle stiffness (N/m), muscle tone (Hz), and muscle elasticity. The secondary variable was perceived pain threshold.ResultsNo significant differences between the groups were found for biomechanical properties and perceived pain threshold in the studied muscles.ConclusionForward head posture has no impact on muscle stiffness, tone, and elasticity, nor does it increase the pressure sensitivity of superficial neck muscles in healthy, mildly symptomatic office workers. It is most likely that not incorrect posture of the cervical spine, but probably other factors combined with forward head posture, like comorbid acute and chronic cervical pain and musculoskeletal disorders or prolonged sitting, contribute to changes in active myofascial tone and tensegrity as well as increased pressure sensitivity of neck muscles.  相似文献   
29.
The purpose of this study was to determine the effect of respiratory muscle fatigue on intercostal and forearm muscle perfusion and oxygenation in patients with heart failure. Five clinically stable heart failure patients with respiratory muscle weakness (age, 66±12 years; left ventricle ejection fraction, 34±3%) and nine matched healthy controls underwent a respiratory muscle fatigue protocol, breathing against a fixed resistance at 60% of their maximal inspiratory pressure for as long as they could sustain the predetermined inspiratory pressure. Intercostal and forearm muscle blood volume and oxygenation were continuously monitored by near-infrared spectroscopy with transducers placed on the seventh left intercostal space and the left forearm. Data were compared by two-way ANOVA and Bonferroni correction. Respiratory fatigue occurred at 5.1±1.3 min in heart failure patients and at 9.3±1.4 min in controls (P<0.05), but perceived effort, changes in heart rate, and in systolic blood pressure were similar between groups (P>0.05). Respiratory fatigue in heart failure reduced intercostal and forearm muscle blood volume (P<0.05) along with decreased tissue oxygenation both in intercostal (heart failure, -2.6±1.6%; controls, +1.6±0.5%; P<0.05) and in forearm muscles (heart failure, -4.5±0.5%; controls, +0.5±0.8%; P<0.05). These results suggest that respiratory fatigue in patients with heart failure causes an oxygen demand/delivery mismatch in respiratory muscles, probably leading to a reflex reduction in peripheral limb muscle perfusion, featuring a respiratory metaboreflex.  相似文献   
30.
针刺表情肌对特发性面神经麻痹表情肌功能恢复的影响   总被引:1,自引:0,他引:1  
目的:观察不同针刺方法对特发性面神经麻痹表情肌功能恢复的疗效。方法:将134例特发性面神经麻痹患者随机分为针刺表情肌组(表情肌组79例)和常规取穴组(55例)。表情肌组在颅顶肌额腹、眼轮匝肌、口轮匝肌、颊肌行围刺治疗;常规取穴组穴取患侧地仓、颊车、阳白、四白、攒竹等,行针刺治疗。治疗2个疗程后比较两组疗效。结果:表情肌组有效率为94.9%,优良率为92.4%;常规取穴组有效率为70.9%,优良率为52.7%,两组疗效经统计学检验,P<0.05,差异具有统计学意义。结论:表情肌针刺疗法治疗特发性面神经麻痹优于常规取穴针灸方法。  相似文献   
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