Being a carpal bone scaphoid has an important role in wrist movements. Wrist joint is a synovial modified ellipsoid joint where movements like flexion, extension and adduction, abduction take place around two axes (transverse and anteroposterior). These movements at the wrist joint are associated with considerable range of movements at the midcarpal joint, as same group of muscles act on both o...

How do we map joint actions we participate in onto joint actions we observe others performing, such as when a couple dancing tango observes another couple dancing tango? We investigated this question using a task in which participants were instructed to perform individual or joint movements in synchrony with individual or joint movements observed on a computer screen. The observed movements sta...

Background: The determinant role of different movements to strengthen the quadriceps on rate of knee joint co-contraction, hamstring to quadriceps muscle activity ratio and vastus medialis to vastus lateralis muscle activity ratio provides useful information for therapists, coaches and athletes about the role of each movement in the rehabilitation of patients with anterior cruc...

The preceding study demonstrated that normal subjects compensate for the additional interaction torques generated when a reaching movement is made during voluntary trunk rotation. The present paper assesses the influence of trunk rotation on finger trajectories and on interjoint coordination and determines whether simultaneous turn-and-reach movements are most simply described relative to a tru...

In this paper we show that staggered joint interpolation [7] with maximaRy smooth joint motion can account for both the hand paths and tangential velocity profiles observed in human. multi-joint atm movements. Arm trajectories were recorded while subjects perfotmed point-to-point movements in a vertical plane. ‘Ihe shape of the tangential velocity profile of the hand was found to be symmeuica.l...

After a sufficiently long training phase, the network described in the preceding chapters can provide the required joint angles for any desired arm position. However, setting the joints to these angles is left to the joint servo motors of the arm. Such motors achieve the target position by changing their torque in opposite direction to any angular deviation from the target joint settings. For s...

BACKGROUND Limb movements are generally driven by active muscular contractions working with and against passive forces arising in muscles and other structures. In relatively heavy limbs, the effects of gravity and inertia predominate, whereas in lighter limbs, passive forces intrinsic to the limb are of greater consequence. The roles of passive forces generated by muscles and tendons are well u...

During multijoint limb movements such as reaching, rotational forces arise at one joint due to the motions of limb segments about other joints. We report the results of three experiments in which we assessed the extent to which control signals to muscles are adjusted to counteract these "interaction torques." Human subjects performed single- and multijoint pointing movements involving shoulder ...