Differentiating temporal electromyographic waveforms between those with chronic low back pain and healthy controls

Objectives. Temporal activation patterns from abdominal and lumbar muscles were compared between healthy control subjects and those with chronic low back pain.

Study design. A cross-sectional comparative study.

Background. Synergist and antagonist coactivity has been considered an important neuromuscular control strategy to maintain spinal stability. Differences in onset times and amplitudes have been reported from trunk muscle EMG recordings between healthy subjects and those with low back pain;however, evaluating temporal EMG waveforms should demonstrate whether differences exist in the ability of those with and those without low back pain to respond to changing perturbations.

Methods. The Karhunen–Loève expansion was applied to the ensemble-average EMG profiles recorded from four abdominal and three trunk extensor muscle sites while subjects performed a leg-lifting task aimed at challenging lumbar spine stability. The principal patterns were derived and the weighting coefficients for each pattern were the main dependent variables in a series of two-factor (group and muscle) mixed models.

Results. Three principal patterns explained 96% of the variance in the temporal EMG profiles. The s revealed statistically significant group and muscle main effects (P<0.05) for the principal pattern and significant group by muscle interactions (P<0.05) for patterns two and three. Post hoc analysis showed that patterns were not different among all muscle sites for the healthy controls, but differences were significant for the low back pain group.

Conclusions. The healthy group coactivated all seven sites with the same temporal pattern of activation. The low back pain group used different activation patterns indicative of a lack of synergistic coactivitation among the muscle sites examined.

Relevance

These results provide a foundation for developing a diagnostic classifier of neuromuscular impairment associated with low back pain, that could be used to evaluate the effectiveness of therapeutic interventions to improve muscle coactivation.     

Muscle strengthening through high-resistance weight training in patients with neuromuscular disorders

The effects of weight training on muscle performance were quantified by measuring (1) maximum force (muscle strength), (2) force-time integral--area under force-time plot during 60 seconds of sustained maximum force (work done), and (3) fatigue index--percentage reduction in maximum force. Subjects included 16 patients with gradually progressive neuromuscular disorders. The muscle strength of these patients ranged from 2% to 75% normal before the program. For patients with markedly to moderately weak muscles, maximum force increased by 80% +/- 48%, force-time integral increased by 132% +/- 93%, and mean fatigue index was significantly reduced from 53% +/- 18% to 34% +/- 7.7% during the study period. Severely weak muscles (less than 10% normal strength) generally did not improve. High-resistance weight training can significantly increase muscle performance of patients with neuromuscular disease if disease progression is slow and initial muscle strength is greater than 15% normal.     

Performance of elbow tracking under constant torque disturbance in normotonic stroke patients and normal subjects

Objective. In this study, the influences of externally imposed constant torque on the voluntary elbow movements of stroke and normal subjects were investigated quantitatively.

Background. Muscle weakness, spasticity and incoordination are the major factors that interfere with stroke patient’s limb functions. Imposing external torque disturbance may worsen the motor performance. This experiment was designed to investigate the effects of small constant external torque on the performance of voluntary elbow movements.

Methods. Tracking of a ramp-and-hold angle trajectory in the direction of extension was used as the main task for performance assessment. Each subject repeated the same tracking movement six times in each of three loading conditions: no, assistive or resistive loading. Five normal and six stroke subjects were recruited for this study. We used parameters extracted from movement trajectory and processed electromyograms as the performance indicators.

Results. For normal subjects, there was no difference in the tracking performance in the three loading conditions. For stroke patients, the affected side had inferior performance to the healthy side in the free loading condition and the difference diminished in assistive and resistive loading conditions as the performance of the affected side improved. Integrated electromyograms of biceps or triceps did not show significant changes in different loading conditions.

Conclusions. Small externally imposed constant torque, either resistive or assistive, may improve motor performance of affected elbows in stroke patients.

Relevance. Most of the currently available prostheses are passive devices, aiming at providing better support and improving stability. The results of the current study imply that an active prosthetic device that applies a small constant torque to the hemiparetic elbow can improve its motor performance in stroke patients. The direction of external torque is to assist the weaker side of the antagonistic muscle pair.     

健康青年握力与人体计量资料的相关性

目的探讨健康青年的握力与人体计量资料的相关性。方法采集32名右利手健康青年的年龄、身高、体重、前臂长、前臂围、手长、手宽和掌厚等人体计量资料,用Dynamometer G100型握力器测试右手握力。结果所有受试者的握力与除年龄(r=-0.009)以外的人体计量资料均有明显相关性(r=0.479～0.754,PP<0.01),且与手长和手宽的相关性更密切(r=0.850,P<0.01)。逐步回归分析结果显示手长和手宽是握力主要预测因素(R²=0.723)。结论健康青年的握力与手部的人体计量资料密切相关,其中手长和手宽可以较好地预测握力大小。     

Fatigue and neuromuscular diseases.

PURPOSE: To identify the role of fatigue, its evaluation and its causes in the pathophysiology context of acquired or hereditary neuromuscular diseases of the spinal anterior horn cell, peripheral nerve, neuromuscular junction and muscle. MATERIAL AND METHODS: A literature review has been done on Medline with the following keywords: neuromuscular disease, peripheral neuropathy, myopathy, fatigue assessment, exercise intolerance, force assessment, fatigue scale and questionnaire, then with the terms: Fatigue Severity Scale, Chalder Fatigue Scale, Fatigue Questionnaire, Piper Fatigue Scale, electromyography and the combination of the word Fatigue with the following terms: Amyotrophic Lateral Sclerosis (ALS), Post-Polio Syndrome (PPS), Guillain-Barre Syndrome, Immune Neuropathy, Charcot-Marie-Tooth Disease, Myasthenia Gravis (MG), Metabolic Myopathy, Mitochondrial Myopathy, Muscular Dystrophy, Facioscapulohumeral Dystrophy, Myotonic Dystrophy. RESULTS: Fatigue is a symptom very frequently reported by patients. Fatigue is mainly evaluated by strength loss after an exercise, by change in electromyographic activity during a given exercise and by questionnaires that takes into account the subjective (psychological) part of fatigue. Due to the large diversity of motor disorders, there are multiple clinical expressions of fatigue that differ in their presentation, consequences and therapeutic approach. CONCLUSION: This review shows that fatigue has to be taken into account in patients with neuromuscular diseases. In this context, pathophysiology of fatigue often implies the motor component but the disease evolution and the physical obligates of daily life also induce an important psychological component.     

Brain activity is similar during precision and power gripping with light force: an fMRI study

Handgrips can be broadly classified into precision and power grips. To compare central neuronal control of these tasks, functional magnetic resonance imaging was used in 14 healthy right-handed volunteers, who repetitively squeezed non-flexible force transducers with a precision grip and a power grip of the dominant hand. The relative grip force levels and movement rates (0.45 Hertz) of both tasks were comparable. Peak isometric grip forces ranged between 1% and 10% of the maximum voluntary force. Reflecting the additional recruitment of extrinsic hand muscles and the higher absolute force, activation of the contralateral primary sensorimotor cortex (M1/S1) and ipsilateral cerebellum was significantly stronger during power than during precision grip. No brain areas exhibited stronger activity during the precision grip than during the power grip. The left M1/S1 and right cerebellum showed a positive linear relationship with the grip force, while the right angular gyrus and left superior frontal gyrus showed a gradual increase in activity when less force was applied. However, these force-dependent modulations of brain activity were similar for the precision and power grip tasks. No brain region was specifically activated during one task but not during the other. Activity during precision gripping did not exceed the activity associated with power gripping possibly because the precision grip task was not challenging enough to call on dexterous fine motor control.     

老年女性肌少症与平衡功能的相关性

目的 探讨老年女性肌少症与平衡功能之间的相关性。方法 2017年9月至11月,招募60~70岁老年女性224例,根据肌容量、握力和6米步速分为正常组(n = 198)和肌少症组(n = 26)。比较两组闭眼单足站立时间和5次坐立试验时间;闭眼单足站立时间和5次坐立试验时间分别与肌容量、握力和6米步速行Pearson相关分析。结果 老年女性肌容量、握力、6米步速单个指标异常率分别为20.5%、14.3%和2.2%,肌少症发生率11.6%。肌少症组闭眼单足站立时间显著短于正常组(t = 4.072, P < 0.001),5次坐立试验时间显著长于正常组( t = -5.461, P < 0.001);正常组闭眼单足站立时间与6米步速明显正相关( r = 0.675, P < 0.01);肌少症组闭眼单足站立时间与6米步速( r = 0.492)和握力(r = 0.286)均显著正相关(P < 0.001);两组5次坐立时间均与握力( r = 0.351, r = 0.462)、肌容量(r = 0.258, r = 0.321)、6米步速(r = 0.337, r = 0.396)显著正相关(P < 0.001)。 结论 相对肌肉质量和力量而言,老年女性增龄过程中肌肉功能保持相对较好。患肌少症的老年女性动静态平衡功能均下降。静态平衡主要与肌肉功能关系较大,动态平衡与肌肉质量、力量和功能均有关联。     

Neuromuscular and psychological characteristics in subjects with work-related forearm pain

There are scant data available on the neuromuscular and psychological characteristics of patients with cumulative trauma disorders. We compared 16 subjects with work-related forearm and hand pain in the dominant upper limb with 9 age-matched control subjects. Pain subjects were divided into two groups based on nerve conduction studies: eight subjects were in the study group for median neuropathy at the wrist (MN, median transcarpal latency >2.3 ms), and eight were in the study group for electrodiagnostically negative pain (EN). Average pain, forearm muscle tenderness, grip strength, pinch strength, and wrist flexor and extensor strength were measured. The Health Status Questionnaire and the Beck Depression Inventory were used to measure health perception and depressive symptoms, respectively. Work satisfaction was determined by a newly devised scale. Statistical analysis was by analysis of variance and planned comparison analysis. The MN and EN groups did not significantly differ on any of the measures except median transcarpal latency. Both pain groups had significantly (P < 0.05) greater average pain, greater extensor muscle tenderness, higher Beck Depression Inventory scores, higher pain rating, and poorer physical functioning on the Health Status Questionnaire than did the normal control group. Grip strength and wrist extension force were diminished in both cumulative trauma groups compared with control subjects; however, only grip strength in the MN group and wrist extension force in the EN group differed significantly (P < 0.05) from control subjects. Only the EN group had significantly less work satisfaction than did the control group. Overall, both pain groups differed from control subjects and shared similar characteristics, with the exception of median neuropathy.     

指屈肌主动不足条件下屈指运动时神经肌肉的调控

目的 观察健康人指屈肌主动不足条件下进行屈指运动时,大脑对肌肉的调控特点。方法 2019年3月,招募健康女性大学生12例,在腕关节中立位和最大屈曲条件下测量右手最大静握力,完成50%最大随意等长收缩屈指运动15次(动力性收缩)。同步采集表面肌电图(sEMG)和脑电图,记录sEMG平均振幅和平均功率频率,以及皮质-肌肉相干性(CMC)。结果 腕最大屈曲时握力显著低于腕中立位时(t = 5.757, P < 0.001),指屈肌肌电平均功率频率降低(t = -2.152, P = 0.043)。动力性收缩时,指伸肌肌电平均振幅明显低于指屈肌(t > 2.964, P < 0.01);腕最大屈曲条件下指屈肌平均振幅显著提高(t = 4.135, P < 0.001),CMC升高(t > 2.203, P < 0.05)。结论 腕极限屈曲可诱导指屈肌主动不足;在指屈肌主动不足条件下进行屈指运动时,脑相关皮质区活动增强,可能为脑的代偿机制。     

Physiological and methodological aspects of rate of force development assessment in human skeletal muscle

Rate of force development (RFD) refers to the ability of the neuromuscular system to increase contractile force from a low or resting level when muscle activation is performed as quickly as possible, and it is considered an important muscle strength parameter, especially for athletes in sports requiring high‐speed actions. The assessment of RFD has been used for strength diagnosis, to monitor the effects of training interventions in both healthy populations and patients, discriminate high‐level athletes from those of lower levels, evaluate the impairment in mechanical muscle function after acute bouts of eccentric muscle actions and estimate the degree of fatigue and recovery after acute exhausting exercise. Notably, the evaluation of RFD in human skeletal muscle is a complex task as influenced by numerous distinct methodological factors including mode of contraction, type of instruction, method used to quantify RFD, devices used for force/torque recording and ambient temperature. Another important aspect is our limited understanding of the mechanisms underpinning rapid muscle force production. Therefore, this review is primarily focused on (i) describing the main mechanical characteristics of RFD; (ii) analysing various physiological factors that influence RFD; and (iii) presenting and discussing central biomechanical and methodological factors affecting the measurement of RFD. The intention of this review is to provide more methodological and analytical coherency on the RFD concept, which may aid to clarify the thinking of coaches and sports scientists in this area.     

Impact of middle ear effusion on balance performance in children

Middle ear effusion (MEE) is a common childhood disease characterized by accumulation of fluid in the middle ear. MEE treatment focuses on the resultant conductive hearing loss. Recently, researchers have investigated the potential effects of MEE on balance.

Purpose: The purpose of this study was to compare balance of children with MEE to that of healthy children and to examine whether a relation exists between balance skills and the degree of muscle strength.

Methods: Twenty children with MEE and twenty healthy children aged 4.5 - 7.5 years underwent balance and strength sub-tests of Bruininks - Oseretsky Test of Motor Performance (BOTMP) and electronystagmography recordings (ENG). Parents completed a questionnaire designed to elicit their perceptions of their child's balance abilities in daily living activities.

Results: MEE children performed significantly worse than did the control group on BOTMP balance sub-test. BOTMP strength subtest indicated that children with MEE had poorer muscle strength than the control group, although the difference was not significant. ENG results showed no pathologic recordings in both study group and control group. Finally, a significant correlation was found between parents' responses on the questionnaire and their child's performance on BOTMP balance subtest.

Conclusions: MEE may negatively impact children's balance, while muscle strength is less affected. Furthermore, the BOTMP appears to be a sensitive assessment of balance disturbances in children with MEE.     

The immediate effects of manual massage on power-grip performance after maximal exercise in healthy adults

OBJECTIVE: Research into the effects of manual massage on physical performance has proved inconclusive, with studies primarily examining the major muscle groups of the lower extremities. Grip performance is essential for object manipulation, as well as for many grip-dependent activities and sports; but there have been no studies to determine the effects of manual massage on immediate grip performance in healthy subjects. The purpose of this study was to assess the effects of using manual massage to improve power-grip performance immediately after maximal exercise in healthy adults. STUDY DESIGN: This was a pretest/post-test study. SETTING: The study took place in a suburban allied health school. SUBJECTS: Fifty-two (52) volunteer massage-school clients, staff, faculty, and students participated. Interventions: Subjects randomly received either a 5-minute forearm/hand massage of effleurage and friction (to either the dominant hand or nondominant hand side), 5 minutes of passive shoulder and elbow range of motion, or 5 minutes of nonintervention rest. OUTCOME MEASURES: Power-grip measurements (baseline, postexercise, and postintervention) were performed on both hands using a commercial hand dynamometer. These measurements preceded and followed 3 minutes of maximal exercise using a commercial isometric hand exerciser that produced fatigue to 60% of baseline strength. RESULTS: After 3 minutes of isometric exercise, power grip was consistently fatigued to at least 60% of baseline, with recovery occurring over the next 5 minutes. Statistical analyses involving single-factor repeated-measures analyses of variance (p = 0.05) with Bonferroni a priori tests (p = 0.0083) demonstrated that massage had a greater effect than no massage or than placebo on grip performance after fatigue, especially in the nondominant-hand group. CONCLUSIONS: Manual massage to the forearm and hand after maximal exercise was associated with greater effects than nonmassage on postexercise grip performance. The present data do support the use of a 5-minute manual massage to assist immediate grip performance after fatigue in healthy subjects.     

Force assessment in periodic paralysis after electrical muscle stimulation

OBJECTIVE: To obtain an objective measure of muscle force in periodic paralysis, we studied ankle dorsiflexion torque during induced paralytic attacks in hyperkalemic and hypokalemic patients. SUBJECTS, PATIENTS, AND METHODS: Dorsiflexor torque after peroneal nerve stimulation was recorded during provocative tests on 5 patients with hypokalemic or hyperkalemic disorders and on 2 control subjects (1995-2001). Manual strength assessment was simultaneously performed in a blinded fashion. Standardized provocation procedures were used. RESULTS: The loss of torque in hyperkalemic patients roughly paralleled the loss of clinically detectable strength, whereas in the hypokalemic patients, pronounced torque loss occurred well before observed clinical effects. No dramatic changes occurred in the control subjects. Torque amplitude decreased more than 70% in all patients during the provocation tests; such decreases were associated with alterations induced in serum potassium concentrations. CONCLUSIONS: Stimulated torque measurement offers several advantages in characterizing muscle dysfunction in periodic paralysis: (1) it is independent of patient effort; (2) it can show a definitely abnormal response early during provocative maneuvers; and (3) characteristics of muscle contraction can be measured that are unobservable during voluntary contraction. Stimulated torque measurements can characterize phenotypic muscle function in neuromuscular diseases.     

Muscle fatigue and muscle injury

The purpose of this review is to acquaint the reader with the neurobiology of muscle fatigue. Muscle fatigue is a complex, multifactorial process. The authors have covered the chain of events bringing about skeletal muscle contraction and the manner in which fatigue may affect each step. Advances in technology continue to increase understanding of central fatigue. Many excellent studies of peripheral fatigue have been designed to delineate the mechanisms that influence the excitation-contraction coupling, energy supply, and force generation processes. Although much of this work has considered mechanisms in isolation, different mechanisms may be responsible under different conditions. Fatigue is a common complaint among patients with a variety of neuromuscular and metabolic diseases. Armed with an enhanced knowledge of the mechanisms of muscle fatigue, one can more fully recognize the signs and symptoms of metabolic disorders and neuromuscular diseases and use diagnostic testing. The clinician should anticipate the role of muscle fatigue in injury and focus on injury prevention strategies, especially during the restorative phase of rehabilitation. As a clinician-scientist concerned with optimizing patients' and athletes' performance, one must design ways to identify, measure, and treat muscle fatigue. Beyond illustrating what is currently known about muscle fatigue, the authors hope this review inspires the reader to solve problems of great clinical importance to patients and athletes alike.     

Descriptive analysis of the developmental progression of grip position for pencil and crayon control in nondysfunctional children

This study was designed to investigate the developmental progression in pencil and crayon grip. The subjects were 320 nondysfunctional children aged 3.0 to 6.11 years, with 20 boys and 20 girls at each 6-month age interval. On the basis of a review of the literature, developmental pencil and crayon grips were defined for the study, and the type of grips each child used to perform a drawing task and a coloring task were recorded. Many children at each age level used mature pencil grips. A developmental progression, however, was shown by the percentage change of children at each age level who used mature grips. Forty-eight percent of the youngest group used mature grips, compared with 90% of the oldest children. Two pencil grips-dynamic and lateral tripod-appear to be common in older children. Differences in the developmental progression of pencil grip were noted between boys and girls and between a drawing task and a coloring task.     

Assessment of skeletal muscle fatigue in men with coronary artery disease using surface electromyography during isometric contraction of quadriceps muscles

OBJECTIVE: To evaluate whether using surface electromyography to assess skeletal muscle fatigue during an isometric exercise has the potential to be clinically useful in patients with coronary artery disease (CAD). DESIGN: Double sample comparative study. SETTING: Cardiac rehabilitation service in France. PARTICIPANTS: Sixteen men with documented CAD and 9 age-matched healthy men. INTERVENTIONS: Assessment of quadriceps skeletal muscle fatigue on an isokinetic apparatus with surface electromyography measurements and a symptom-limited exercise test in a laboratory. MAIN OUTCOME MEASURES: The maximal voluntary isometric force (MVIF) of the quadriceps was quantified as a measure of muscle strength and isometric endurance was defined as the time required to sustain a contraction at 50% of MVIF until exhaustion. Surface electromyography signals were recorded from the vastus lateralis, rectus femoris, and vastus medialis during isometric endurance. The root mean square (RMS) and the median frequency (MF) were directly calculated on a computer and then normalized (as a percentage of the initial value). RESULTS: Muscle strength did not differ significantly between the patients with CAD and the healthy subjects (229+/-21N/m vs 228+/-52N/m), but isometric endurance was reduced (64+/-17s vs 90+/-7s, P <.01). The RMS values showed a significantly higher increase in the healthy subjects versus the patients with CAD for the vastus lateralis and vastus medialis ( P <.001). The MF values were significantly lower for the vastus lateralis, rectus femoris ( P <.01), and vastus medialis ( P <.05) in patients with CAD compared with the healthy subjects. CONCLUSIONS: Skeletal muscle fatigue occurs sooner in men with CAD relative to matched healthy men, despite similar muscle strength. This finding may be the result of an abnormality of skeletal muscle function and may play an important role in measuring functional capacity. In addition, it may be a useful tool to assess the efficacy of cardiac rehabilitation interventions.     

Fatiguing exercise enhances hyperalgesia to muscle inflammation

Since many people with chronic fatigue present with pain and many people with chronic pain present with fatigue, we tested if fatigue would enhance the response to pain in male and female mice. We further tested for the activation of brainstem nuclei by the fatigue task using c-fos as a marker. Fatigue was induced by having mice spontaneously run in running wheel for 2 h. Carrageenan (0.03%) was injected into the gastrocnemius muscle either 2 h before or 2 h after the fatigue task. The mechanical sensitivity of the paw (von Frey filaments), muscle (tweezers), grip force and running wheel activity was assessed before and 24 h after injection of carrageenan. Both male and female mice that performed the fatigue task, either before or after intramuscular injection of carrageenan, showed an enhanced mechanical sensitivity of the paw, but not the muscle. Ovariectomized mice showed a similar response to male mice. There was a decrease in running wheel activity after carrageenan injection, but no change in grip force suggesting that mice had no deficit in motor performance induced by the carrageenan. C-fos expression was observed in the nucleus raphe pallidus, obscurus, and magnus after the fatigue task suggesting an increased activity in the raphe nuclei in response to the fatigue task. Therefore, widespread hyperalgesia is enhanced by the fatigue response but not hyperalgesia at the site of insult. We suggest that this effect is sex-dependent and involves mechanisms in the brainstem to result in an enhanced hyperalgesia.     

髌骨软化症患者膝关节等速肌力测试

目的 分析髌骨软化症患者膝关节周围肌力特征,并比较其与健康人的差异。方法 2021年3月,采用等速肌力测试与训练系统,对70例单膝发病髌骨软化症患者(观察组)和35例健康人(对照组)进行膝关节不同角速度(60°/s和180°/s)的屈、伸等速肌力测试。结果 60°/s和180°/s时,观察组患侧屈、伸肌峰力矩、峰力矩体质量比、总功均显著低于对照组(U> 1097.0,P <0.001);观察组患侧60°/s屈、伸肌和180°/s时伸肌峰力矩、峰力矩体质量比、总功均低于观察组健侧(|Z|> 2.121, P <0.05)。60°/s和180°/s时,观察组患侧屈伸肌力比值均明显大于健侧和对照组(U> 1810.0,|Z|>3.691, P <0.01)。结论 髌骨软化症患者的患膝屈、伸肌肌爆发力和耐力均减弱,膝关节肌力存在失衡现象。     

Practice-related changes in lumbar loading during rapid voluntary pulls made while standing

Objective. To determine if five days of practice on a novel dynamic, multi-joint pulling task resulted in lower magnitudes of lumbar loading or a more consistent relationship between pulling force and lumbar loading.

Design. A repeated measures design compared how practice influenced the magnitude of lumbar torque and the correlations between lumbar torque and pulling force.

Background. Previous studies suggest that practice can decrease the magnitude of lumbar loading on simple manual material handling tasks, but it is unknown whether practice reduces lumbar loading for more complex tasks. Neither is it known whether the consistency of lumbar loading increases with practice.

Methods. Ten healthy adults practiced impulse-like horizontal pulls to targets equaling 20%, 40% and 80% of their estimated maximal dynamic pulling force over 5 days. Movements were unrestrained, other than keeping the feet flat on the ground. We used a four-segment, sagittal plane inverse dynamics model to compute lumbar, hip, knee, and ankle torques on days 1 and 5 from ground reaction forces and moments, pulling forces, and kinematics.

Results. An analysis of variance showed significant practice-related changes in lumbar torque at the time of peak pulling force (lumbar torque_peakPF). The lumbar torque_peakPF decreased for the 20% pulls, did not change for the 40% pulls, and increased for the 80% pulls. Two subjects showed a significant decrease in lumbar torque_peakPF for all three force levels. Coefficients of determination between pulling force and lumbar torque (r²_PF,LT: a measure of the consistency of the relationship between these two variables) were significantly higher on day 5 than day 1.

Conclusions. Practice on a novel pulling task changed the magnitude of lumbar torques and increased their correlation with pulling force, suggesting that subjects learned strategies that improve motor control of lumbar torques.Relevance

The study showed that the magnitude and consistency of lumbar loading changed spontaneously as subjects practiced a novel multijoint pulling task. Such changes may decrease the risk of low-back injury.     

神经肌肉病患者功能评定的临床应用进展

大部分神经肌肉病属于罕见病,其中相对较为常见的是Duchenne型肌营养不良和脊髓性肌萎缩症。神经肌肉病的一个重要特征是进行性残疾,因此功能评定对评价神经肌肉病患者的疾病严重程度、运动功能以及活动能力非常重要。目前功能评定包括肌力、关节活动度、姿势、活动能力等方面,涉及多种评定工具,但尚未形成统一标准。精确、合理的评定方法对多学科管理团队为患者制定个体化治疗方案具有重要意义。