Evaluation of 3 pushrim-activated power-assisted wheelchairs in patients with spinal cord injury.

Objective: To assess differences between manual wheelchairs and 3 pushrim-activated power-assisted wheelchairs (PAPAWs): Servomatic A and B and E-motion.

Design: Repeated measures.

Setting: Rehabilitation hospital.

Participants: Volunteers with spinal cord injuries (N=52).

Interventions: Ten subjects propelled the wheelchairs on a dynamometer, 46 evaluated each wheelchair on indoor and outdoor courses, and 10 evaluated their ability to transfer themselves and their wheelchairs into and out of their car.

Main Outcome Measures: Oxygen consumption per unit time (V˙o2) and heart rate were measured during propulsion on the dynamometer. Wheelchair efficiency on the indoor and outdoor courses was evaluated on the basis of heart rate, completion time, handrim push frequency, and patient satisfaction.

Results: On the dynamometer, decreases in V˙o2 and heart rate were similar with the 3 PAPAWs compared with manual wheelchairs. On the outdoor course, heart rate was significantly decreased by PAPAWs compared with manual wheelchairs and patient satisfaction was better with Servomatic devices than with the E-motion device. Indoors, the course completion time was longer with the E-motion wheelchair than with other wheelchairs in the overall population, and handrim push frequency was higher with the E-motion wheelchair than with other wheelchairs in the subgroup with T12 to L1 injuries. Car transfer ability was lower with PAPAWs than with manual wheelchairs.

Conclusions: Differences exist across PAPAWs. Compared with E-motion, the 2 Servomatic PAPAWs were easier to use outdoors, and difficulty transferring into/out of the car was similarly increased with all 3 PAPAWs.