Evaluation of venous return in lower limb by passive ankle exercise performed by PHARAD

Design of a Device for Lower Limb Prophylaxis and Exercise

The problem of immobility of legs leading to a potentially life threatening condition including deep venous thrombosis (DVT) is well known. The reduced mobility of leg affects a large number of patients in a wide range of clinical scenarios spanning from swelling of the legs to pulmonary embolism. In normal human beings, an elegant system of venous return, both active and passive is responsible for prevention of deep venous thrombosis. The paper proposes a prophylaxis and exercise device that mimics the natural principles of venous return to promote the blood flow. The device is based on electromechanical actuation, and simultaneous alternating compression mechanism, that is compact and, suitably form fitted in design and additionally requires no specialised training for the usage. The device was tested on a healthy volunteer on two different days and findings support the efficacy of the prophylaxis and exercise device in significantly improving the blood flow rate in the lower limb. The prototype device is considered as a major step towards designing a clinically validated lower limb device.

Design of a non-invasive pulse rate controlled deep vein thrombosis prophylaxis lower limb device

Patients with lower limb dysfunctions have a risk of developing deep vein thrombosis (DVT) symptoms if they are in a sitting posture for a long duration. In addition, unconscious patients undergoing a long hour surgery are also prone to DVT problems which further complicates the health of the patient under treatment. A prototype design in the form of an assistive and portable device to overcome deep vein thrombosis (DVT) is developed for surgical and non-surgical applications. The portable device facilitates the movement of the lower limb around the ankle to promote blood flow and overcome DVT problem. The device is designed using a pair of actuators that translates the linear motion to axial flexion and extension movement of the ankle. The ankle movement is synchronized with the patient's heartbeats to promote blood flow and complete the venous movement. In addition, an electrically driven intermittent pneumatic compression layer is wrapped around the calf muscle to further enhance the blood flow in the lower limb. The integrated device is lightweight and portable which can be issued by the hospital centers to the patients for domestic utilization.

Integrated Wheelchair-Compatible Support System for Sit-To-Stand Movements Support

This study proposes a novel integrated wheelchair-compatible support system for wheelchair users with partial or complete paralysis. This system not only provides sit-to-stand and stand-to-sit (STS) learning support for stroke and spinal cord injury patients but also enhances the independence of wheelchair users. It integrates a lower limb movement support unit with a wheelchair and supports STS movement by moving the seat up and down linearly. It also measures the ground reaction force (GRF) on both sides of the body and supports proper STS movement to allow users to improve their movements and postures. Individual experiments were conducted to evaluate the system-provided STS movement support for two patients with partial paralysis and one patient with complete paralysis. Patients with partial paralysis, both hemiplegic and quadriplegic, were able to operate the system and perform the STS movement learning with visual biofeedback. Moreover, using our system, a wheelchair user with complete paraplegia was able to perform tasks at an elevated position independently. Therefore, this system will help wheelchair users achieve the self-motor-learning of STS movement and enhance their quality of life independently.

Robot-Assisted Eccentric Contraction Training of the Tibialis Anterior Muscle Based on Position and Force Sensing

The purpose of this study was to determine the clinical effects of a training robot that induced eccentric tibialis anterior muscle contraction by controlling the strength and speed. The speed and the strength are controlled simultaneously by introducing robot training with two different feedbacks: velocity feedback in the robot controller and force bio-feedback based on force visualization. By performing quantitative eccentric contraction training, it is expected that the fall risk reduces owing to the improved muscle function. Evaluation of 11 elderly participants with months training period was conducted through a cross-over comparison test. The results of timed up and go (TUG) tests and 5 m walking tests were compared. The intergroup comparison was done using the Kruskal-Wallis test. The results of cross-over test indicated no significant difference between the 5-m walking time measured after the training and control phases. However, there was a trend toward improvement, and a significant difference was observed between the training and control phases in all subjects.

Exercise system for eccentric tibialis anterior contraction to improve ambulatory function

This study has developed a device and system for the exercise of eccentric contraction of the tibialis anterior, with the objective of maintaining ambulatory function. A system was built that allows for exercises of appropriate load and speed, by providing the trainee with force data in the form of visual feedback. An experimental verification with two healthy participants shows small variation in the Myoelectric data during the repetitive exercise. The result suggest the possibility of higher reproducibility of the proposed exercise in comparison with manual exercise. As a clinical test, elderly ambulatory participants who frequented a day care facility performed exercises for one month (twice weekly) using the proposed device and exercise system. To verify the exercise results, a TUG test was performed, which is an assessment index for functional mobilization capacity. Shorter TUG in the majority of the participants suggests a possible beneficial effect in ambulatory function.