The purposes of this project were to determine mental training-induced strength gains (without performing physical exercises) in the little finger abductor as well as in the elbow flexor muscles, which are frequently used during daily living, and to quantify cortical signals that mediate maximal voluntary contractions (MVCs) of the two muscle groups. Thirty young, healthy volunteers participate...

Simultaneous recordings of action potentials (APs) of multiple single motor units (MUs) were obtained in brachialis and biceps (caput breve) muscles during si­ nusoidally modulated isometric contractions of elbow flexor muscles and during sinusoidal flexion/extension movements in the elbow against a preload in the exten­ sion direction. The results show that MUs typically fire in one short burs...

1. Arm movements toward a target involving motion at the shoulder and elbow joints and restricted to the sagittal plane were investigated. During some movements, target location changed suddenly, thus requiring an intentional correction of the trajectory by the human subject. 2. The reaction time to correct the trajectory was comparable to the reaction time to initiate the movement. 3. Coordina...

It has been hypothesized that the magnocellular red nucleus (RNm) contributes to compensation for motor impairments associated with lesions of the pyramidal tract. To test this hypothesis, we used stimulus triggered averaging (StTA) of electromyographic (EMG) activity to characterize changes in motor output from the red nucleus after lesions of the pyramidal tract. Three monkeys were trained to...

This study compared shoulder and elbow joint forces and moments between weight-relief lifts (WRLs) and sitting pivot transfers (SPTs) among manual wheelchair users with spinal cord injury (SCI) (N = 13) during biomechanical laboratory assessment. Minimum and maximum values were reported for each triaxial component of the joint force at the dominant shoulder and elbow during SPTs (leading and tr...

[Purpose] Muscle tone is known to predict the motor function of the upper extremity within 12 months after onset in stroke survivors. The aim of this study was to investigate whether motor function of the upper extremity can predict the risk of hypertonia in chronic stroke survivors, and to analyze the correlation between the two variables to determine the predictive validity. [Subjects and Met...

Young women are less fatigable than young men for maximal and submaximal contractions, but the contribution of supraspinal fatigue to the sex difference is not known. This study used cortical stimulation to compare the magnitude of supraspinal fatigue during sustained isometric maximal voluntary contractions (MVCs) performed with the elbow flexor muscles of young men and women. Eight women (25....

The soft tissue at the tip of the olecranon is very thin, leading to the frequent occurrence of wound complications after total elbow arthroplasty. To cover a soft tissue defect of the elbow, the flexor carpi ulnaris muscle flap is thought to be appropriate for reconstruction of the elbow with regard to its size, location, and blood supply. We got positive clinical results, so we report our exp...

40 Previous studies in neurologically intact subjects have shown that motor coordination can be 41 described by task-dependent combinations of a few muscle synergies, defined here as a fixed 42 pattern of activation across a set of muscles. Arm function in severely impaired stroke survivors 43 is characterized by stereotypical postural and movement patterns involving the shoulder and 44 elbow. ...

An analysis of arm movements involving forward projection of the hand in order to reach for and grasp a target at different orientations is presented. The reaching movements required shoulder flexion, elbow extension, and wrist pronation or supination. The relation between elbow and shoulder instantaneous angular position proved to be consistent from trial to trial of each task, independent of ...