Yutaka Nishimoto

Development of a Hand Motion Assist Robot for Rehabilitation Therapy by Patient Self-Motion Control

This paper presents a new hand motion assist robot for rehabilitation therapy. The robot is an exoskeleton with 18 DOFs and a self-motion control, which allows the impaired hand of a patient to be driven by his or her healthy hand on the opposite side. To provide such potential that the impaired hand is able to recover its ability to the level of a functional hand, the hand motion assist robot is designed to support the flexion/extension and abduction/adduction motions of fingers and thumb independently as well as the opposability of the thumb. Moreover, it is designed to support a combination motion of the hand and the wrist. The design specifications and experimental results are shown.

Long-term follow-up after limb salvage in skeletally immature children with a primary malignant tumor of the distal end of the femur.

BACKGROUND Skeletally immature children with a primary malignant tumor in the distal end of the femur are candidates for limb-salvage surgery; however, functional impairment due to subsequent limb-length discrepancy must be considered. Our aim was to evaluate the long-term clinical outcome of limb salvage in patients with a sarcoma of the distal end of the femur who were eleven years old or less, focusing on limb-length discrepancy and complications. METHODS The cases of forty children were retrospectively reviewed in a multicenter study based on the responses to a questionnaire. Twenty-eight patients had had endoprosthetic reconstruction, and twelve had had biological reconstruction. Functional evaluation was based on the Musculoskeletal Tumor Society scoring system, with numerical values from 0 to 5 points assigned for each of the following six categories: pain, function, emotional acceptance, use of supports, walking ability, and gait. These values were added, and the functional score was presented as a percentage of the maximum possible score. Limb-length discrepancy was measured with orthoroentgenograms. Complications and their treatment were analyzed. Patient survival and the survival of the reconstructions were analyzed with use of the Kaplan-Meier method. RESULTS Seven patients died and thirty-three remained alive, for a survival rate of 82% at ten years postoperatively. For the surviving patients, the mean follow-up periods (and standard deviations) were similar for the twenty-two who had endoprosthetic reconstruction (13.2 +/- 3.9 years) and the eleven who had biological reconstruction (10.4 +/- 4.4 years). All patients had reached skeletal maturity. The mean final functional score was 74% +/- 18% in the endoprosthetic reconstruction group and 68% +/- 17% in the biological reconstruction group (p = 0.37). For the nineteen patients who underwent limb-lengthening, the mean functional score increased significantly from 65% +/- 21% before the procedure to 81% +/- 11% after the lengthening (p = 0.0016). There were five early and twenty-eight late complications. In the endoprosthetic reconstruction group, the most frequent complications were deep infection and aseptic loosening. In the biological reconstruction group, the most frequent complications were implant breakage and nonunion. Revision surgeries were required in seventeen patients, including five who had an amputation. The rate of survival of the endoprosthetic reconstructions was 77% at five years and 51% at ten years postoperatively, whereas the rate of survival of the biological reconstructions was 46% at both five and ten years postoperatively. CONCLUSIONS Endoprosthetic or biological reconstructions as limb salvage provided good functional outcome in skeletally immature children with a malignant bone tumor of the distal aspect of the femur despite a high rate of revisions and limb-lengthening procedures.

A design of fine motion assist equipment for disabled hand in robotic rehabilitation system

This paper reports a newly designed system intended to aid in hand rehabilitation. The motion assistance equipment consists of three parts: mechanisms for the fingers and thumb, a base of these mechanisms, and a motion assistance mechanism for the wrist. The structure of each mechanism is designed to achieve independent, fine motion assistance, especially, for the individual fingers. First, the features of each mechanism in the equipment are explained. Next, the control systems are introduced, which are constructed to realize a self-motion control strategy (i.e., the motion is controlled by its user). Using this control system, the transient response and steady state characteristics of the motion assistance mechanisms for the thumb are evaluated. Consequently, the possibility of practical application is found in regard to some improved points.

Osteosarcoma in the elderly over 60 years: A multicenter study by the Japanese musculoskeletal oncology group†

Few studies have described the characteristics and prognostic factors of osteosarcoma patients aged over 60 years.

Development of virtual reality exercise of hand motion assist robot for rehabilitation therapy by patient self-motion control

This paper presents a virtual reality-enhanced hand rehabilitation support system with a symmetric master-slave motion assistant for independent rehabilitation therapies. Our aim is to provide fine motion exercise for a hand and fingers, which allows the impaired hand of a patient to be driven by his or her healthy hand on the opposite side. Since most disabilities caused by cerebral vascular accidents or bone fractures are hemiplegic, we adopted a symmetric master-slave motion assistant system in which the impaired hand is driven by the healthy hand on the opposite side. A VR environment displaying an effective exercise was created in consideration of systems characteristic. To verify the effectiveness of this system, a clinical test was executed by applying to six patients.

Hand Rehabilitation Support System Based on Self-Motion Control, with a Clinical Case Report

This paper presents a virtual reality-enhanced hand rehabilitation support system with a symmetric master-slave motion assistant for independent rehabilitation therapies. This system consists of a hand exoskeleton device and a lateral symmetric master-slave motion assistant system joined with a virtual reality (VR) environment. Since most disabilities caused by cerebral vascular accidents or bone fractures are hemiplegic, we adopted a symmetric master-slave motion assistant system in which the impaired hand is driven by the healthy hand on the opposite side. Furthermore, a VR environment displaying an enjoyable exercise was introduced. To verify the effectiveness of this system, a clinical trial was executed using one subject.

Nonunion of a first rib fracture causing thoracic outlet syndrome in a basketball player: a case report.

Fractures of the first rib occur infrequently in athletes. This report describes a basketball player with thoracic outlet syndrome (TOS) resulting from nonunion of a first rib fracture with a hypertropic callus. Conservative therapy had been ineffective for 1 year after the patient sustained the injury, and he had complained of numbness in the left upper extremity when his shoulder was in abduction and external rotation. We performed resection of the first rib through a transaxillary approach to achieve neurovascular decompression. This resulted in immediate resolution of the symptoms. There was no recurrence of the numbness in the left upper extremity at 2 years after surgery. Previous reports of sports-associated first rib fracture have indicated that it has a relatively good prognosis. However, nonunion of a first rib fracture may lead to TOS that is unresponsive to conservative treatment. Therefore, this type of fracture should be followed-up carefully.

Tremor suppression control of Meal-Assist Robot with adaptive filter

A robot that supports independent living by assisting with eating and other activities involving the use of the hand using the operators own hand would be helpful for people suffering from tremors of the hand or any other body part. In this study, the proposed adaptive filter estimates tremor frequency with a time-varying property and individual differences online, and insulates the voluntary motion signal from the sensor signal containing tremor components. As a result, the developed human-machine interface makes it possible for the person with a tremor to manipulate the supporting robot without causing operability to deteriorate and without hazards due to improper operation.

Flexion-extension motion assistance using an upper limb motion-assist robot based on trajectory estimation of reaching movement

People of all ages have suffered impairment in traffic accidents or sport accidents, and these individuals worry about dysfunction of their upper limbs, but they can recover from dysfunction by rehabilitation. In this study, we developed an assistive robot for upper limb movement that has high rehabilitation effectiveness. To achieve this, we proposed a reaching movement support method that considers an expanding joint’s range of motion. The effectiveness of our method is shown through experiments.

Telerehabilitation for Fingers and Wrist Using a Hand Rehabilitation Support System and Robot Hand

Abstract Therapists create rehabilitation programs for patients to help them recover from and mitigate their lost abilities. This paper proposes a novel hand telerehabilitation system. The system consists of a hand rehabilitation support system for the patient, an anthropomorphic robot hand for the therapist, and a remote monitoring system for diagnosing the degree of recovery. The therapist applies the force to the robot hand. The force is then transmitted to the patient using the rehabilitation support system. An advanced robot hand and remote monitoring system using virtual reality technology have been developed. Specifications of the robot hand are shown. The safety of the system was demonstrated experimentally for healthy persons.