Standing performance of persons with paraplegia

This study measures standing stability of four individuals with paraplegia using knee-ankle-foot orthoses (KAFOs) with a center-of-force monitoring platform as compared with similar data from 10 neurologically healthy subjects. Both groups were compared under conditions of quiet standing with eyes open and closed and with hands on and off parallel bars. Individuals with paraplegia were also tested under similar conditions with the ankles of their KAFOs mechanically unlocked and with bilateral functional neuromuscular stimulation of the quadriceps muscles. Sway path, mean amplitude, and mean frequency were measured for each subject. We found that postural stability in paraplegic individuals using KAFOs compared favorably with the control group under conditions of eyes open and closed with hands on parallel bars; however, visual information was much more important for paraplegic individuals during quiet stance. Unlocking the ankles of the KAFOs resulted in an increase in swap path and mean frequency. Functional muscular stimulation of the quadriceps muscles resulted in standing stability slightly less than with KAFOs. Although KAFOs may not be the ideal assistive device for various reasons, postural stability appears reasonable, and other proposed orthoses must be comparable in order to be considered as an alternative.