Energy expenditure during gait using the walkabout and isocentric reciprocal gait orthoses in persons with paraplegia.

OBJECTIVE

To compare the energy expenditure during walking using the Walkabout Orthosis (WO) and the Isocentric Reciprocal Gait Orthosis (IRGO) in persons with paraplegia.

DESIGN

A randomized cross-over design.

PATIENTS

Ten individuals with complete T9-12 paraplegia.

INTERVENTIONS

Subjects were trained to walk using the WO and the IRGO with elbow crutches.

MAIN OUTCOME MEASURES

Subjects' energy expenditures during walking using each orthosis over three different terrains--flat tile, flat carpet, and 4 degrees uphill ramp--were compared. Data collected included expired ventilation (L/min), heart rate (beats/ min), speed of walking (m/min), oxygen uptake (VO2; L/min and mL/kg/min), oxygen cost (O2 cost; mL/kg/m), and Physical Cost Index (PCI; beats/m). Subjects walked at a self-selected pace.

RESULTS

Subjects walked significantly slower with the WO than with the IRGO, regardless of the surface (p < .05). The average speed of walking ranged from 5.2+/-1.3 for the WO on the tiled surface to 11.5+/-2.3m/min for the IRGO on the carpeted surface. Despite marked differences in self-selected walking speeds between the two orthoses, there were no differences in either heart rate or VO2 among orthoses or surfaces. However, the O2 cost of gait was significantly greater for the WO (range, 3.95 to 4.91mL/kg/m) compared with the IRGO (range, 1.6 to 1.8mL/kg/m). Likewise, the PCI was significantly greater using the WO (range, 8.4 to 10.3beats/m) than the IRGO (range, 4.3 to 7.0beats/m).

CONCLUSIONS

This study shows that the metabolic demands of walking with the WO are greater than walking with the IRGO in individuals with T9-12 paraplegia.