POSTURAL MOTOR PROGRAMMING IN PARAPLEGIC PATIENTS DURING REHABILITATION

One of the basic aims in the rehabilitation of thoracic spinal cord in jured (SCI) patients concerns the regaining of sitting posture control . This implies the development of new postural strategies requiring th e adjustment of motor programming processes. The aim of this study was to investigate the time course of postural reorganization during acti ve, clinical rehabilitation of thoracic SCI patients with different SC I levels. Thus changes in motor programming in sitting balance control were investigated in two groups of complete low or high thoracic SCI patients. At several stages during the rehabilitation process an exper iment was held in which sitting posture was perturbed systematically u sing submaximal reaching movements over four reaching distances. This bimanual reaching task was presented as a visual precue choice reactio n time (RT) task in which reaching distance (i.e. grade of postural pe rturbation) was precued: Results indicated that in both high and low t horacic SCI patients RTs in movements involving postural perturbation became shorter during the course of the rehabilitation period. However , low thoracic SCI patients were generally slower in the programming o f balance perturbing movements than high thoracic SCI patients, a phen omenon that did not change over time. Furthermore, initial differences in RTs as a function of grade of postural perturbation disappeared in both groups in the course of the rehabilitation phase. Precue benefit , equally large for both groups, did not change as a function of rehab ilitation time, It is concluded that the observed phenomena signify th e gradual development of new central postural control processes in bot h SCI groups during rehabilitation. Low thoracic SCI patients, having more residual sensorimotor functions, seem to adopt more complex strat egies in maintaining and restoring sitting balance that take longer to specify and to programme. High thoracic SCI patients seem to rely on simpler strategies using more passive postural support.