Energy expenditure with advanced lower limb orthoses and with conventional braces.

The purpose of this study was to measure the relative energy expenditure through quantification of oxygen consumed in subjects wearing various advanced designs of lower limb orthoses and conventional braces. The designs developed at the Institute of Rehabilitation Medicine were compared with conventional braces and were found to result in a reduction of oxygen consumed from 9% to 16% depending on the type of orthosis. Portable Douglas bags were employed and the gas analyzed per unit distance-time with relation to volume of oxygen and carbon dioxide under steady state conditions. Savings in consumed oxygen are rather consistent with the advanced orthotic designs, even though the subjects varied with respect to age, weight, sex and disability. No data were taken without a device as the subjects under this circumstance frequently required an auxiliary aid, which would introduce another variable.