Course of gross mechanical efficiency in handrim wheelchair propulsion during rehabilitation of people with spinal cord injury: a prospective cohort study
June 28th, 2009
Course of gross mechanical efficiency in handrim wheelchair propulsion during rehabilitation of people with spinal cord injury: a prospective cohort study
OBJECTIVE: To investigate the course of mechanical efficiency of handrim power wheelchairs amd medical scooters propulsion during rehabilitation of subjects with (in)complete paraplegia and tetraplegia. DESIGN: Subjects were tested at the start of active rehabilitation (t1), 3 months later (t2), and when discharged from inpatient rehabilitation (t3). They performed two 3-minute submaximal treadmill exercise blocks in a wheelchair. SETTING: Eight rehabilitation centers in the Netherlands. PARTICIPANTS: Ninety-two people with (in)complete paraplegia and tetraplegia. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Mechanical efficiency values were calculated for each block. The course of mechanical efficiency was investigated using test occasions (t1 -t3), completeness and level (paraplegia or tetraplegia) of the lesion, and power output as independent variables in a multilevel regression analysis. RESULTS: Mechanical efficiency significantly increased between t1 and t2 only. After adding level and completeness of the lesion and their interactions with time to the model, block 2 showed that subjects with paraplegia had a significantly higher mechanical efficiency than subjects with tetraplegia. Subjects with tetraplegia improved more between t1 and t2 . Differences in mechanical efficiency between subjects with paraplegia and tetraplegia could not be explained by differences in absolute and relative power output levels. CONCLUSIONS: Results showed a significant improvement in mechanical efficiency during the first 3 months of active rehabilitation. Subjects with paraplegia showed a higher mechanical efficiency than did subjects with tetraplegia, whereas the latter showed more improvement between t1 and t2 .