Abstract
The aim of this study was to investigate the loading demands placed on the intact limb in terms of joint moments and power for active transfemoral and transtibial amputees in comparison to a group of ablebodied subjects. Four (4) transtibial, 4 transfemoral amputees and 10 ablebodied subjects walked at 1.2m.s1 along a walkway whilst kinematic data from both the intact and prosthetic limbs, and kinetic data from the intact limb only were collected. A Panasonic VHS video camera was used to film subjects walking in the sagittal plane with simultaneous force data collected from a Kistler force platform. The amputees were found to compensate for the functional loss of one or more joints by increasing net joint moments and power output on their intact limb compared to ablebodied subjects. At the intact limb ankle, the range of motion, peak dorsiflexor moment and power generation at toeoff increased. At the intact limb knee, power generation during stance and extensor moments and power absorption at toeoff increased. At the intact limb hip, extensor moment and power absorption during stance, and hip flexor moment and power generation at toeoff increased. These findings were partly attributed to the prostheses used but mainly to adaptation mechanisms displayed by transfemoral and transtibial amputees. They have implications for the mobility of amputees and the long term health of their joints. It was recommended that prosthesis design, prosthesis fitting and training in the use of the prosthesis were all factors which could be investigated with a view to minimising intact limb loading.