Mechanical orthoses such as hip ankle foot orthoses that include the walkabout, the hip ankle linked orthosis, the prime walk, para walker and hip guidance orthosis, the advanced reciprocal gait orthosis, and the isocentric reciprocal gait orthosis have all been used for patients with spinal cord injury in therapeutic treatment in providing standing and walking activities. Although the positive effects of mechanical orthoses are well demonstrated , there are several reasons why an optimal level of walking for SIC patients has backs. not been achieved especially due to the high energy consumption and overloading on upper limb joints when walking with mechanical orthoses. paraplegic patients usually demonstrate high energy forward propulsion and swinging of the lower limbs. the use of a powered lower limb orthoses may offer a solution to resolving these drawbacks.
powered lower limb orthoses can be useful devices for walking and standing in SCI patients. the purpose of these orthoses is to provide torque to targeted joints during walking. ideally, this mechanical assistance is designed to produce overall kinematic patterns similar to that of normal walking. the use of a powered orthosis has been shown to provide better function in terms of gait parameters compared to a mechanical orthosis. the effectiveness of this type of orthosis has been demonstrated in previous studies in this field. kang et al. reported that hip flexion angles and the pelvic angle were both reduced during walking with a powered orthosis, but walking speed was increased compared to an reciprocal gait orthosis(RGO). ohta et al. demontrated that both gait speed and the step length increased when the knee and hip joints were actuated by a powered RGO. the cosmesis of walking may be improved, and lateral and vertical compensatory motions reduced when hip joint actuators are activated. arazpour ed al. reported that a poeered hip orthosis provided positive effects on the kinematics and temporal-spatial parameters of gait during level-ground walking trials as compared to IRGO. kawashima et al. showed that the weight-bearing control orthosis (WBCO)enabled SCI patients to walk with a higher speed than mechanical orthoses when using similar energy expenditure. walking with the WBCO also leas to improvement of the energy cost of walking in paraplegic patient, even though they only provided power to one joint (e.g. the hip or ankle ). a powered gait orthosis that has synchronized powered movement between the hip and knee joints has recently been desingned and developed, and its effectiveness on the gait of a single SCI subject has been reported. arazpour et al. demonstrated that improvement in step length, speed of walking. and cadence were observed in walking withnthe new powered gait orthosis as compared to the standard IRGO. maximum hip flexion and vertical compensatory motions were reduced with powered gait orthosis compared to IRGO. in this study, we aimed to evaluate the effect of a similar powered gait orthosis with synchronized actuated movement between knee and hipjoints on temporal-spatial parameters and kinematics of rothotic gait on a series of volunteer SCI patients.