Reflex Torque Response to Movement of the Spastic Elbow: Theoretical Analyses and Implications for Quantification of Spasticity

A parametric model of the human reflex torque response to a large-amplitude, constant angular velocity elbow extension was developed in order to help quantify spasticity in hemiparetic stroke patients, and to better understand its pathophysiology. The model accounted for the routinely observed leveling of torque (i.e., a plateau) at a mean angular increment of 51°±10° s.d. (n=98) after the initial rise. This torque plateau was observed in all eight subjects, and in 98 of 125 trials across 25 experimental sessions. The occurrence of this plateau cannot be explained by decreases in elbow flexor moment arms during elbow extension. Rather, the plateau is attributable to a consistent leveling in muscle activation as confirmed both qualitatively from recordings of rectified, smoothed electromyograph (EMG) activity, and quantitatively using an EMG coefficient model. A parametric model was developed in which the pattern of muscle activation in the stretch reflex response of elbow flexors was described as a cumulative normal distribution with respect to joint angle. Two activation functions, one related to biceps and the other to brachioradialis/brachialis, were incorporated into the model in order to account for observations of a bimodal angular stiffness profile. The resulting model yielded biologically plausible parameters of the stretch reflex response which may prove useful for quantifying spasticity. In addition, the model parameters had clear pathophysiological analogs, which may help us understand the nature of the stretch reflex response in spastic muscles. © 1999 Biomedical Engineering Society. PAC99: 8719Rr, 8719Xx, 8719St, 8719Nn, 8719Ff, 8710+e     

Stroke-related dementia: Rates,risk factors and implications for future research

Stroke is a risk factor for dementia and dementia predisposes to stroke. Dementia prevalence in subjects with stroke is comparable to that seen in stroke-free subjects who are 10 years older. However, until recently the prevalence, time course and risk factors for dementia in relation to the occurrence of stroke was unclear owing to conflicting reports from individual studies. Data now available from a meta-analysis of studies of pre- and post-stroke dementia, show that heterogeneity between individual studies is largely explained by study methods and case-mix. Pooled dementia estimates are consistent with 1-in-10 patients being demented prior to first stroke, 1-in-10 developing new dementia soon after first stroke, and over 1-in-3 being demented after a recurrent stroke. After the first year, cumulative incidence of dementia is little greater than expected on the basis of recurrent stroke alone. Medial temporal lobe atrophy, female sex and family history, are more strongly associated with pre-stroke dementia, whereas the characteristics and complications of the stroke and the presence of multiple lesions in time and place are more strongly associated with post-stroke dementia, indicating the likely impact of optimal acute stroke care and secondary prevention in reducing the burden of dementia. Future studies are needed to develop a predictive risk score for post-stroke dementia, to evaluate short cognitive screening instruments to identify high risk patients with milder cognitive impairment, and to clarify the interaction between degenerative and vascular processes in the development of dementia.     

气象环境因素与脑卒中发病的相关性研究

脑卒中是发病率高、致残率高、致死率高以及复发率高的脑血管疾病,其主要病因有脑小动脉硬化、脑动脉粥样硬化、血管先天发育异常等,常见的危险因素有高血压、糖尿病、高脂血症、心脏病、吸烟等。有研究发现,脑卒中的发病与气象、空气污染存在关联性,异常天气是脑卒中的危险因素之一。本文对气象因素中气温、气压、湿度、空气污染与脑卒中发病关系及发病机制作一综述,旨在为脑卒中的防治提供一定的理论依据。     

Clinical Differences Between Stroke and Stroke Mimics in Code Stroke Patients

BackgroundThe code stroke system is designed to identify stroke patients who may benefit from reperfusion therapy. It is essential for emergency physicians to rapidly distinguish true strokes from stroke mimics to activate code stroke. This study aimed to investigate the clinical and neurological characteristics that can be used to differentiate between stroke and stroke mimics in the emergency department (ED).MethodsWe conducted a retrospective observational study of code stroke patients in the ED from January to December 2019. The baseline characteristics and the clinical and neurological features of stroke mimics were compared with those of strokes.ResultsA total of 409 code stroke patients presented to the ED, and 125 (31%) were diagnosed with stroke mimics. The common stroke mimics were seizures (21.7%), drug toxicity (12.0%), metabolic disorders (11.2%), brain tumors (8.8%), and peripheral vertigo (7.2%). The independent predictors of stroke mimics were psychiatric disorders, dizziness, altered mental status, and seizure-like movements, while current smoking, elevated systolic blood pressure, atrial fibrillation on the initial electrocardiogram, hemiparesis as a symptom, and facial palsy as a sign suggested a stroke. In addition, the likelihood of a stroke in code stroke patients tended to increase as the number of accompanying deficits increased from the following set of seven focal neurological deficits: hemiparesis (or upper limb monoparesis), unilateral limb sensory change, facial palsy, dysarthria, aphasia (or neglect), visual field defect, and oculomotor disorder (P < 0.001).ConclusionSome clinical and neurological characteristics have been identified to help differentiate stroke mimics from true stroke. In particular, the likelihood of stroke tended to increase as the number of accompanying focal neurological deficits increased.     

针刺配合吞咽康复训练治疗脑卒中后吞咽障碍的研究

目的 研究针刺配合吞咽康复训练治疗脑卒中后吞咽障碍效果。方法 选取2017年1月~2018年12月在我院治疗的脑卒中后吞咽障碍患者150例,随机分为对照组和观察组,各75例。对照组实施吞咽康复训练,观察组在对照组基础上配合针刺,对比两组治疗总有效率、吞咽功能障碍评分、生存质量评分以及不良事件发生情况。结果 观察组总有效率为97.33%,高于对照组的78.67%,差异有统计学意义（P＜0.05）;治疗后两组吞咽功能障碍评分、生存质量评分均较治疗前升高,且观察组改善优于对照组,差异有统计学意义（P＜0.05）;观察组不良事件发生率为5.33%,低于对照组的26.67%,差异有统计学意义（P＜0.05）。结论针刺配合吞咽康复训练治疗脑卒中后吞咽障碍有效率高,可促进患者吞咽功能恢复,提高其生存质量,并可有效预防呛咳、误吸等不良事件的发生,具有良好的治疗效果。     

首发缺血性卒中患者睡眠质量与生存质量关系研究

目的研究首发缺血性卒中患者睡眠质量与卒中特异性生存质量的关系。方法将符合研究标准的缺血性卒中病例经睡眠质量评分后分为睡眠障碍组与无睡眠障碍组,运用脑卒中影响量表（SIS3.0）评估患者卒中特异性生存质量情况。结果睡眠障碍组患者体力,情绪,交流,日常活动能力,移动能力,手功能等维度的生存质量评分均明显低于无睡眠障碍组（P〈0.05,0.01,0.001）。结论首发缺血性卒中患者的睡眠质量与生存质量关系密切,伴睡眠障碍的缺血性卒中患者其生存质量较差,表现在体力,情绪,交流,日常活动能力,移动能力,手功能等方面。睡眠障碍对缺血性卒中患者的生存质量有明显影响。     

Identification of Static and Dynamic Components of Reflex Sensitivity in Spastic Elbow Flexors Using a Muscle Activation Model

Static and dynamic components of the stretch reflex were studied in elbow flexors of 13 hemiparetic brain-injured individuals. Constant-velocity joint rotations were applied to the elbow, and the resulting stretch reflex torque and electromyographic responses were recorded in the biceps brachii and brachioradialis muscles. Ten elbow extension velocities between 6 and 150 ° s^-1 were applied in random order. The resulting reflex torque response was plotted as a function of elbow angle and fitted with a mathematical model designed to depict elbow flexor activation. We found that four of the six model parameters were essentially independent of test velocity. Conversely, 73% (19/26) of cases involving the other two model parameters were dependent on velocity of joint extension (p<0.05). We conclude from these results that four of the model parameters reflect the static reflex response while the two remaining velocity-dependent parameters reflect the dynamic reflex response. To describe overall velocity dependence of stretch reflexes in spastic elbow muscles, the two dynamic reflex parameters were fitted to a fractional exponential function of velocity, similar to a model previously used to describe spindle firing rate in the cat hindlimb. We found that the mean velocity exponent of the dynamic reflex parameters was 0.24 + 0.17 (s.d.) (N = 13), a value similar to that for muscle spindle velocity sensitivity in reduced animal preparations. We conclude that both static and dynamic reflex sensitivities can be measured by examining different aspects of the torque/angle relation associated with the reflex response to a large-amplitude ramp stretch of the elbow. © 2001 Biomedical Engineering Society. PAC01: 8719St, 8719Ff, 8710+e     

Effect of Muscle Biomechanics on the Quantification of Spasticity

The impact of muscle biomechanics on spasticity was assessed by comparison of the reflex responses of the elbow and metacarpophalangeal (MCP) flexor muscles in individuals with chronic spastic hemiplegia following stroke. Specifically, methods were developed to quantify reflex responses and to normalize these responses for comparison across different muscle groups. Stretch reflexes were elicited in the muscles of interest by constant velocity ramp-and-hold stretches at the corresponding joint. The muscles were initially passive, with the joint placed in a midrange position. Estimates of biomechanical parameters were used to convert measured reflex joint torque and joint angle into composite flexor muscle stress and stretch. We found that the stretch reflex response for the MCP muscle group had a 74% greater mean stiffness modulus than that for the elbow muscle group, and that the reflex threshold was initiated at an 80% shorter mean muscle stretch. However, we determined that initial normalized fiber length was significantly greater for the experiments involving the MCP muscles than for those involving the elbow muscles. Increasing the initial composite fiber length of the elbow flexors produced significant reduction of the reflex threshold (p < 0.001), while decreasing the initial length of the MCP flexors significantly reduced their measured reflex stiffness (p < 0.001). Thus, biomechanical parameters of muscle do appear to have an important effect on the stretch reflex in individuals with impairment following stroke, and this effect should be accounted for when attempting to quantify spasticity. © 2001 Biomedical Engineering Society. PAC01: 8719Rr     

脑卒中后抑郁情绪对预后的影响

抑郁情绪是脑卒中后常见的一种精神症状 ,发生率高。本研究对一组脑卒中后幸存者的抑郁情绪及对预后的影响进行了调查 ,旨在引起临床医生对脑卒中后抑郁情绪的重视 ,在治疗脑卒中的同时 ,对抑郁情绪进行心理或药物的干预。1　研究对象与方法1.1　研究对象病例选择标准 :①符合全国第四届脑血管病学术会议制定的诊断标准 ,并经ＣＴ证实 ,首次脑卒中的患者 ;②无阳性精神障碍史及家族史 ;③神志清楚 ,无理解功能障碍 ;④出院后随访二年以上。依照上述纳入标准 ,从我院 1997年 1月至 1998年 12月的住院的病例中选择出 15 5例脑卒中后的幸存者。…     

脑卒中与继发性癫癎

目的:探讨首发脑卒中患者继发性癫癎的发病率、发病时间与脑卒中病变部位的关系。方法:回顾性分析经我院近3年来治疗的659例首发脑卒中住院患者的临床资料。结果:首发脑卒中患者继发癫癎发生率为8.19%(54/659)。癫癎发作与卒中病变部位有关,累及皮层或邻近皮层者易继发癫癎(53.33%,24/45)。54例继发癫癎中68.52%为早发性癫癎(起病后2周内),余31.48%为晚发性癫癎(起病2周以后)。以脑出血继发早发性癫癎为主(81.25%,13/16);脑梗死则易发生晚发性癫癎(60.00%,12/20)。结论:分析首发卒中后癫癎的发病特点有助于指导临床治疗。     

高频重复经颅磁刺激对后遗症期脑卒中后吞咽功能障碍的疗效观察

目的 探讨高频重复经颅磁刺激对后遗症期脑卒中后吞咽功能障碍患者疗效。方法 选取2017年1月~2018年6月本院收治的40例后遗症期脑卒中后吞咽功能障碍患者为研究对象,采用电脑产生随机数字法将患者分为观察组和对照组,各20例。两组患者均接受常规吞咽功能训练,观察组患者在此基础上加用经颅磁刺激治疗,对照组患者接受同样刺激参数的假刺激线圈给予的治疗,比较两组患者吞咽功能评分及环咽肌表面肌电图最大波幅变化情况。结果 治疗后,对照组、观察组患者吞咽功能评分分别为（4.10±0.59）分、（4.65±0.64）分,差异无统计学意义（P＞0.05）;环咽肌表面肌电图最大波幅值分别为（668.00±39.33）μV、（761.00±43.61）μV,组间比较,差异无统计学意义（P＞0.05）。结论 高频重复经颅磁刺激对后遗症期脑卒中后吞咽功能障碍患者的吞咽功能无明显改善。     

社会支持系统对脑卒中后抑郁的影响

目的探讨社会支持系统对脑卒中患者抑郁状态的影响。方法将80例脑卒中后抑郁患者随机分为支持组和对照组,支持组在常规治疗和护理的基础上增加社会支持的干预措施,对照组只接受常规的治疗和护理,比较两组患者入院后20天、30天的汉密尔顿抑郁量表(HAMD)评分的差异。结果两组患者汉密尔顿抑郁量表评分在干预后20天和30天均降低,而支持组HAMD评分降低更显著,经统计学比较具有显著性差异(t=6.313,8.057,P<0.01)。结论增加社会支持系统可以改善脑卒中后抑郁患者的抑郁状态,在促进疾病康复的同时达到提高护理质量的目的。     

The Association between Parameters of Socioeconomic Status and Hypertension in Korea: the Korean Genome and Epidemiology Study

We investigated the association between socioeconomic status and hypertension in Korea, a country that has experienced a dynamic socioeconomic transition. We analyzed participants of a prospective cohort study—the Korean Genome and Epidemiology Study—enrolled between 2001 and 2003. We recruited 7,089 subjects who underwent a 4-year follow up till 2007. Education and income levels, which are important parameters for socioeconomic status, were stratified into 4 groups. Education level was defined as short (≤ 6 years), mid-short (7–9 years), mid-long (10–12 years), and long (≥ 12 years). Monthly income level was stratified as low (< 500,000 KRW), mid-low (500,000–1,499,999 KRW), mid-high (1,500,000–2,999,999 KRW) or high (≥ 3,000,000 KRW). At baseline, 2,805 subjects (39.5%) were diagnosed with hypertension. Education and income levels were inversely associated with the prevalence and incidence of hypertension (P < 0.001). In multivariate analysis, a shorter duration of education was significantly associated with a higher prevalence of hypertension (P < 0.001), but income level was not (P = 0.305). During the follow-up, 605 subjects (14.2%) were newly diagnosed with hypertension. In multivariate adjusted analysis, the hazard ratios (95% confidence interval) for incident hypertension across the longer education groups were 0.749 (0.544–1.032), 0.639 (0.462–0.884), and 0.583 (0.387–0.879), compared with the shortest education group. There was no significant association between incident hypertension and income across higher income groups: 0.988 (0.714–1.366), 0.780 (0.542–1.121), and 0.693 (0.454–1.056), compared with the lowest income group. In conclusion, education and income levels are associated with the prevalence and incidence of hypertension, but only education is an independent prognostic factor in Korea.     

Stroke education: retention effects in those at low- and high-risk of stroke

OBJECTIVE: Relatively few studies have tracked retention effects of stroke education in low- and high-risk groups. Such information is important to improve the design of stroke prevention programs. METHODS: The frequency of risk factors within the sample was defined as "high" if 30% or more of participants in that group had that risk. Only one stroke risk factor was present at this level in the low-risk group (n=29; all less than 50 years old). The high-risk group was 44 individuals aged 50 years or over, with four stroke risk factors present at this level. Stroke knowledge was tested on three occasions: baseline, post-education, and retention. Education consisted of reading a published stroke brochure. RESULTS: Stroke knowledge improved over time, from baseline to post-education, but not from post-education to retention. The performance of both groups increased, but there was a differential learning effect: low-risk participants learned more than high-risk participants. Important information was learned and included details such when TIA symptoms dissipate. This particular issue was one about which both groups knew little at baseline (less than 15% of combined sample answered this item correctly), but post-education at least 75% of participants got this question correct. CONCLUSION: Both low- and high-risk individuals can learn information about stroke and retain it over the short term. The "durable" effects in learning observed in this study are important because the benefit of brochure-only approaches to education have not yet been convincingly demonstrated. PRACTICE IMPLICATIONS: Information about stroke from education brochures is retained by at-risk populations for at least 1 week.     

脑卒中患者发病及就诊时间的分析

目的：分析脑卒中患者发病就诊时间延迟的相关因素。方法：收集了2008年3～12月在武汉市东西湖区人民医院神经内科住院的脑卒中患者97例,分析其就诊时间延迟的相关因素,并寻求其解决问题的办法。结果：6h内的就诊率为37．11％（36／97）,延迟就诊为62．89％（61／97）,≤6h就诊率出血48．28％（14／29）,缺血32．35％（22／68）。平均就诊时间为13．4h。知识的知晓,重视程度,就诊方式,卒中的类型与及时就诊率相关。结论：缺乏卒中相关知识和不重视对就诊时间有影响,知晓相关知识的患者在6h内的就诊率高。     

Emergency Cervical Carotid Artery Stenting After Intravenous Thrombolysis in Patients With Hyperacute Ischemic Stroke

BackgroundIntravenous recombinant tissue plasminogen activator (IV rtPA) is the mainstay of treatment for acute ischemic stroke to recanalize thrombosed intracranial vessels within 4.5 hours. Emergency carotid artery stenting for the treatment of acute stroke due to steno-occlusion of the proximal internal carotid artery (ICA) can improve symptoms, prevent neurological deterioration, and reduce recurrent stroke risk. The feasibility and safety of the combination therapy of IV rtPA and urgent carotid artery stenting have not been established.MethodsFrom November 2005 to October 2020, we retrospectively assessed patients who had undergone emergent carotid artery stenting after IV rtPA for hyperacute ischemic stroke due to steno-occlusive proximal ICA lesion. Hemorrhagic transformation, successful recanalization, modified Rankin Scale (mRS) score at 90 days, and stent patency at 3 and 12 months or longer were evaluated. Favorable outcome was defined as a 90-days mRS score of ≤ 2.ResultsNineteen patients with hyperacute stroke had undergone emergent carotid artery stenting after IV rtPA therapy. Their median age was 70 (67.5–73.5) years (94.7% men). Among 15 patients with an additional intracranial occlusion after flow restoration in the proximal ICA, a modified TICI grade ≥ 2b was achieved in 11 patients (73.3%). Hemorrhagic transformation occurred in five patients (26.3%); mortality rate was 5.7%. Eleven patients (57.9%) had favorable outcomes at 90 days. Stent patients (94.1%) maintained stent patency for ≥ 12 months.ConclusionWe showed that emergent carotid artery stenting after IV rtPA therapy for hyperacute stroke caused by atherosclerotic proximal ICA steno-occlusion was feasible and safe.     

Detection of Gold Particles in the Neck Skin After Lightning Stroke with Evaporation of an Ornamental Chain

A German couple was struck by lightning. Both patients survived this event. Whereas the husband was unconscious for only a few minutes, his wife fell into coma for 24 h. The lightning stroke entered the body of the woman behind the left ear and left it at the left shoe. The stroke caused a partial evaporation of a gold ornamental chain on the neck, resulting in a tattoo of the neck skin. A biopsy of the skin 6 months after the event showed the accumulation of gold particles of different size in the dermis down to the subcutaneous fatty tissue. In semithin sections, histiocytes, multinucleated foreign giant cells, and fibroblasts were visible with uptaken metallic particles. In transmission electron microscopy, gold globules of up to 30 µm in diameter were visible outside the cells in the collageneous matrix of the connective tissue besides smaller metallic particles up to 5 nm inside lysosomes and residual bodies of phagocytic cells. Four different kinds of gold particles could be differentiated: globules, granular irregular particles, tubules, and tanglelike tracks. In scanning electron microscopy, gold particles were demonstrated by backscatter detection in the connective tissue of subcutis, where the EDX elemental analysis showed strong signals of aurum (Au), copper (Cu), and argentum (Ag). The detected metals were quantified by AAS as 70% gold, 21% silver, and 9% copper, which demonstrates the composition of gold alloy of the neck chain of the patient. Tanglelike tracks and elongated gold deposits represent crystals of gold salts, as detected by electron diffraction and polarization microscopy. Attempts to remove the gold particles from the skin to remove the tattoo should not be undertaken because the gold is deep and widespread.     

多极脑反射治疗脑卒中的疗效与机制

目的　研究多极脑反射治疗仪对脑卒中的治疗效果及机制探讨 .方法　将 2 2 0例脑卒中患者随机分成两组 ,对照组采用常规治疗 ,治疗组加用脑反射治疗 ,经一个疗程的治疗后再次进行神经系统功能缺损评分 .结果　治疗组神经功能缺损评分平均减少 5 5 6± 3 32 ,对照组为 2 36± 2 40 ,经u检验 ,p <0 .0 1,发现治疗组评分明显高于对照组评分 .结论　脑反射治疗仪是一种治疗脑卒中改善神经功能缺损比较有效的方法 .并初步分析了脑反射的治疗机理 .     

音乐疗法对脑卒中后抑郁患者的干预研究

目的探讨音乐疗法对脑卒中后抑郁患者的康复疗效。方法 60例脑卒中后抑郁患者随机分为对照组(30例)和试验组(30例),两组均进行常规治疗,试验组同时配合音乐疗法。治疗1个月前后,分别对患者进行汉密尔顿抑郁量表评分(HAMD)和神经功能缺损评分(CSS)。结果治疗1个月后,两组患者HAMD、CSS评分与治疗前比较均明显下降(t=3.75,P<0.01);两组间比较,试验组治疗1个月后HAMD、CSS评分均低于对照组(t=3.16,P<0.05;t=3.21,P<0.01)。结论音乐疗法干预脑卒中后抑郁患者可改善患者抑郁状态,为脑卒中患者的康复治疗提供了良好的条件。