The purpose of this study was to determine whether elderly adults exhibit deficits in the performance of multi-joint movements. Two groups of subjects (mean ages, 68.9 and 30.1 years, respectively) participated in this experiment. Subjects performed planar arm pointing movements to various targets. One target could be achieved via elbow extension only, while the remaining 3 required both elbow ...

Joint morphogenesis is an important phase of prenatal joint development during which the opposing cartilaginous rudiments acquire their reciprocal and interlocking shapes. At an early stage of development, the prenatal hip joint is formed of a deep acetabular cavity that almost totally encloses the head. By the time of birth, the acetabulum has become shallower and the femoral head has lost sub...

The purpose of this study was to characterize both spatial and temporal patterns of the shoulder joint movement in the upper limb motion when ballet dancers are performing the flaps of swan wings. Twenty-three expert female dancers (Dance group) and 21 inexperienced age-matched females (Control group) participated in the study. Thirty-three reflective markers were attached to the trunk and uppe...

Among the potential biological signals for human-machine interactions (brain, nerve, and muscle signals), electromyography (EMG) widely used in clinical setting can be obtained non-invasively as motor commands to control movements. The aim of this study was to develop a model for continuous and simultaneous decoding of multi-joint dynamic arm movements based on multi-channel surface EMG signals...

Understanding the inherent structure of manipulative hand movements is a critical step toward automatic recognition of manipulative hand movements and toward automatic planning of natural movements for dexterous robots. Manipulative hand movements involve coordinated movements of the digits to manipulate an object within the hand, and are classified as either simultaneous or sequential. Simulta...

This paper presents a new method to generate arm gestures which reproduces the dynamical properties of human movements. We describe a model of synergy, defined as a coordinative structure responsible for the flexible organization of joints over time when performing a movement. We propose a generic method which incorporates this synergy model into a motion controller system based on any iterativ...

When reaching toward a target, human subjects use slower movements to achieve higher accuracy, and this can be accompanied by increased limb impedance (stiffness, viscosity) that stabilizes movements against motor noise and external perturbation. In arthropods, the activity of common inhibitory motor neurons influences limb impedance, so we hypothesized that this might provide a mechanism for s...

Background & Aims: Metaphysical distal radius fractures are common fractures account for almost half of the fractures in Orthopaedic Emergencies. According to different studies, 1-6 weeks cast immobilization after distal radius surgery has been recommended. The aim of this study was to compare outcomes and complications of short-term and long-term immobilization treatment methods. Methods: In a...