Energy cost of walking measurements in subjects with lower limb amputations: a comparison study between floor and treadmill test.

Measuring the energy cost of walking (ECW) is a valid way of assessing the walking efficiency of subjects who were prosthetic users following lower limb amputation. The aim of this study was to determine whether, in these subjects, treadmill and floor ECW measurements are comparable. We tested 24 subjects who had undergone unilateral lower limb amputations for vascular diseases as they walked at a self-selected comfortable speed on the floor and on a treadmill. The tests were conducted at the end of rehabilitative treatment to fit prosthesis. Eight subjects underwent transtibial and 16 transfemoral amputation. The measurements were taken with a portable gas analyzer. The self-selected comfortable speed on the treadmill was significantly lower than that on the floor, where the patients adopted the aid they normally used for walking; oxygen consumption was the same in the two tests. Therefore, for both transtibial and transfemoral patients, ECW was greater during walking on the treadmill. Steady-state heart rate did not differ in the two tests. The data show that the ECW values of the amputated subjects obtained on the treadmill at the end of rehabilitation did not correspond with those they obtained on the floor. The floor test is the one that may better reflect walking with prostheses and aids in everyday life, in subjects with dysvascular lower limb amputation, using the prosthesis for a short time.