Design, Analysis, and Optimization of an Acute Stroke Gait Rehabilitation Device

Stroke is one of the leading causes of adult physical disability, and rehabilitation and hospitalization costs for stroke are among the highest for all injuries. Current rehabilitation techniques are labor intensive and time consuming for therapists and difficult to perform effectively. Research suggests that starting rehabilitation during the acute or subacute stage of recovery results in better outcomes than therapy delivered in the chronic stage. To improve the gait rehabilitation process, robot-assisted gait rehabilitation has gained much interest over the past years. However, many robot-assisted rehabilitation devices have limitations; one of which is being bulky and complex to handle. Large and expensive devices that require special training to operate are less attractive to clinics and therapists, and ultimately less likely to be available to patients especially at the early stage of stroke. To address these limitations, this research proposes a new gait rehabilitation device called the linkage design gait trainer (LGT). The device is based on a walking frame design with a simple four-bar linkage “end-effector” mechanism to generate normal gait trajectories during general walking and exercise. The design of the four-bar linkage mechanism was optimized for a particular gait pattern. A prototype of the device was developed and tested. The kinematics of the device itself and gait kinematics with and without assistance from the device were recorded and analyzed using an optical motion capture system. The results show the linkage mechanism is able to guide the leg of the user during over ground walking. There were some differences in the hip (20.5 deg RMS) and knee (14.8 deg RMS) trajectory between the person walking with and without the device assistance. The study demonstrated the concept and feasibility of this novel gait training device.