Determination of the influence of walking with orthosis on bone osteoporosis in paraplegic subjects based on the loads transmitted through the body.

BACKGROUND: Spinal cord injury is a damage to spinal cord that results in loss of function and mobility below the level of injury. The patients use various orthoses to improve their general health, to decrease bone osteoporosis, and to improve bone mineral density. It was controversial if how much percentage of the loads applied on an orthosis and body complex is transmitted by orthosis. Therefore, it was aimed to determine the magnitude of the loads transmitted by orthosis to find the influence of walking with orthosis on bone mineral density.

METHODS: Three spinal cord injured subjects were recruited in this study. They were trained to walk with a reciprocal gait orthosis. The loads applied on the hip joint of the orthosis and body complex, anatomy and orthosis were measured by use of strain gauges and motion analysis system.

FINDINGS: The mean values of the force and moments transmitted by the orthosis were significantly less than those of the complex. The mean values of adduction moment transmitted through the orthosis and body complex and by the orthosis structure were 1.06 and 0.49N·m/body weight, respectively.

INTERPRETATION: As a higher percentage of loads were transmitted by body than the orthosis, it can be concluded that walking with orthosis could improve bone mineral density, due to the role of bone in transmission of the loads. Therefore, it is recommended that spinal cord injured subjects walk with an orthosis in order to reduce bone osteoporosis, especially for a long period of time.