25 research outputs found
An integrated model for computer assisted diagnosis, treatment and design of insoles for the diabetic foot
The incidence of diabetes has increased significantly in recent decades. In Germany, there is an estimate of three million diabetics and this number is growing at a rate of about 2 percent per year. In the U.S.A., the American Diabetes Association estimates that thirteen million people suffer from this condition, representing 5.2 percent of the entire population and every year, some 35 thousand patients have a lower limb amputated. In Latin America, it has been reported that the prevalence of diabetes is of the order of 14 to 20 percent, according to a research conducted by the WHO's Ad Hoc Diabetes Reporting Group. In Colombia, a study by Ashner et al concludes that the prevalence is 7 percent in both sexes
Transducers for the determination of the pressure and shear stress distribution at the stump-socket interface of trans-tibial amputees
Recent developments in prosthetic socket design have created renewed interest in monitoring the stress distribution at the socket-residual limb interface. Although a few devices for measuring pressure can be found in the literature, none are capable of measuring reliably in areas of high curvature, such as the important area at the patellar tendon bar. Furthermore, few devices can record shear stress, thought to be critical in causing tissue damage. In order to address these issues two new transducers have been designed and evaluated. One design allows the simultaneous recording of the normal and shear stresses at various points of the socket walls, while the other is capable of measuring the three components of the force applied on the patellar tendon. The latter design incorporates a feature that permits displacement of the patellar tendon bar, in order to study the effect of various amounts of indentation of the tendon on the stress distribution around the residual limb. Both transducers were calibrated using dead weights and special jigs to ensure accurate loading conditions. Under laboratory bench conditions the normal-shear force transducer showed: 2.03 per cent full scale output (FSO) hysteresis error for shear stress direction, 1.65 per cent FSO for normal direction; 99.56 per cent FSO overall accuracy for shear direction, and within 99.64 per cent FSO for normal direction; and for the patellar tendon transducer 1.53 per cent FSO hysteresis error for shear direction, 1.85 per cent FSO for shear stress direction; 99.65 per cent FSO overall accuracy for shear direction, and 99.58 per cent FSO for normal direction. During an amputee walking trial the transducers showed 92 per cent to 97 per cent repeatability. The two new transducers were used in conjunction with two other types of transducers, previously designed at the University of Strathclyde, in a series of tests on ten trans-tibial amputees. Sample results for walking activities and a summary of maximum stresses recorded are presented
The patient / prosthesis interface. a critical review of modelling and pressure measurement technologies
Paper examining modelling and pressure measurement technologies in the use of prosthetics for patients
Modelling of the residual limb of trans-femoral amputees using finite element analysis
Paper concerning the modelling of the residual limb of trans-femoral amputees using finite element analysis
The orthotic management of the foot of diabetic patients in the early stages by using a novel computer model
Paper discussing the orthotic management of the foot of diabetic patients in the early stages by using a novel computer model
Load sharing capability of a quadrilateral socket for a trans-femoral amputee
Paper examining load sharing capability of a quadrilateral socket for a trans-femoral amputee
Measurements of the interface pressure between the stump and the socket and its relevance to the prosthetic socket design
Paper concerned with measurements of the interface pressure between the stump and the socket and its relevance to the prosthetic socket design
Pressure distribution at the seating interface of custom-molded wheelchair seats: effect of various materials
Aims to identify which of 4 materials has the most favorable pressure distribution when used in custom-molded seats (CMSs) to assist clinicians in providing appropriate seating for wheelchair-bound individuals who are prone to develop pressure ulcers. Pressure readings were taken at the seat interface with pneumatic pressure sensors and the Talley Pressure Monitor. Peak pressure readings, mean pressure ratio, and peak pressure ratio for the different materials were compared. Results: Foams, Sunmate in particular, produced lower peak-interface pressures and also showed better pressure distribution than did gels. Foams are the preferred insert material with CMSs when increased tissue breakdown risk is present
FE model of a trans-femoral prosthetic socket
Paper discussing the application of a two part limb/socket finite element (FE) model to model socket donning
Comparing the load distribution between quadrilateral and IC trans-femoral sockets
Paper investigating the degree of load sharing between the ischial brim and the rest of the socket for the ischial containment (IC) and quadrilateral (Quad) socket designs