A mathematical model was used to investigate the dynamic behaviour of an above-knee (AK) prosthesis in the swing phase and to analyse the influence of mass and mass distribution on the maximal stump load and the required energy. The model consists of a bondgraph model of the prosthesis and a "walking" model which predicts the walking velocity, step length and the femoral trajectory. Equipment w...

Cyclists with unilateral transtibial amputation (CTA) provide a unique model to study integration of the neuromuscular and bicycle systems while having the option to modify this integration via the properties of the prosthesis. This study included eight CTA and nine intact cyclists. The cyclists pedaled on a stationary bicycle with instrumented force pedals. The CTA group pedaled with a stiff o...

The ankle joint of lower extremity powered prostheses are generally designed to be capable of controlling a single degree of freedom (DOF) in the sagittal plane, allowing a focus on improved mobility in straight walking. However, the single DOF ankle movements are rare in normal lower limb actions such as walking on a straight path or turning when the ankle movements in both sagittal and fronta...

Robotic lower limb prostheses can improve the quality of life for amputees. Development of such devices, currently dominated by long prototyping periods, could be sped up by predictive simulations. In contrast to some amputee simulations which track experimentally determined non-amputee walking kinematics, here, we explicitly model the human-prosthesis interaction to produce a prediction of the...

INTRODUCTION The effect of altered gait on body mechanics presents a stress on patient's sacroiliac joints (SIJ). The gait of the patient is this case report is altered because of a transtibial amputation with prosthesis; he also has a foot drop orthotic. CLINICAL FEATURES A 40-year-old man had left sacroiliac pain. The pain began 3 days before visiting the clinic and has been constant since ...

Introduction Conventional prosthetic ankle foot systems are commonly not able to adapt to different conditions, e.g. stairs and ramps. Walking on inclined surfaces or stairs is therefore a particular challenge for a prosthetic user [1]. So the amputee is forced to compensate the deficits of his prosthesis by adapting the kinematics and kinetics of the proximal and the contra lateral joints [2].

Problems are encountered in using standard prostheses in developing countries, especially when the prostheses need repair and the amputees cannot come back to the workshop. Very simple, low cost and durable prostheses can solve this problem. The solution described has worked well with villagers in some rural areas of Thailand, where the inexpensive prosthesis permits walking bare-foot and throu...

Saito et al. (Modern Plastics 1997;74:175-7) have developed a low-cost transtibial prosthesis made of fiber-reinforced plastic (FRP). The prosthesis is comprised of an aluminum pylon, a cosmetic cover, and a constant cross-section composite foot into which aluminum supports are screwed to increase load-bearing capacity. Replacing these supports with a single integrated FRP stiffener significant...

Alignment will be discussed in terms of what happens as a result of specified changes in the relative positions of the prosthetic components. As a person walks on his prosthesis the conditions which predominate at various stages can be identified: (a) the conditions of no-load, or swing phase, (b) the conditions under which there is full loading or stance phase, (c) the capacity to control the ...

Motion-analysis and FEA can work together even though they are quite different. Motion-analysis software works with CAD assemblies. It starts by translating assembly mating conditions into corresponding kinematics pairs. It then calculates kinematics and dynamics data of the moving mechanism. Each component in mechanism, if viewed separately, is under balanced set of loads: joint reactions and ...