The evaluation of contact areas and pressures in total knee prosthesis is a key issue to prevent early failure. The first part of this study is based on the hypothesis that the patterns of contact stresses on the tibial insert of a knee prosthesis at different stages of the gait cycle could be an indicator of the wear performances of a knee prosthesis. Contact stresses were calculated for a mob...

Rotating hinge knee prostheses have been developed as an advancement of the fixed hinge models. Some authors suggest that this type of prosthesis is associated with a greater risk of aseptic loosening because of the increased stresses to the bone-prosthesis interface; therefore, they are scarcely used as primary implants. The current authors evaluated of a series of 98 rotating hinge knee arthr...

Stump length is an important factor in attaining successful prosthetic rehabilitation in below-knee (BK) amputees. Stability of the stump-prosthesis complex is impaired in the case of a stump shorter than 10 cm. Thus, fitting a prosthesis to a BK amputee with a stump which is very short often requires the use of different prosthetic techniques. In this work, the authors suggest the use of a Swe...

This article presents a virtual prototyping study of a semi-active lower limb prosthesis to improve the functionality of an amputee during prosthesis-environment interaction for level ground walking. Articulated ankle-foot prosthesis and a single-axis semi-active prosthetic knee with active and passive operating modes were considered. Data for level ground walking were collected using a photogr...

Current finite-state control strategies for powered below-knee prosthesis, though effective to the normal gait, can not eliminate the disturbance of abnormal gaits such as slip and stamp. In addition, toe joint is not taken into consideration. This paper presents a finite-state control strategy for a powered below-knee prosthesis with ankle and toe. We first introduce the concerned prosthesis p...

Objective: Few studies have described the complications leading to transfemoral amputation after total knee arthroplasty. The aim of this study was to demonstrate which long term prosthesis-related complications can lead to the loss of a limb after knee joint replacement and to provide clinical guidance regarding the situations that generate an increased likelihood of a patient requiring above ...

Abstract As the essential technology of human-robotics interactive wearable devices, robotic knee prosthesis can provide above-knee amputations with functional compensations to realize their physical and psychological social regression. With development mechanical mechatronic science technology, fully active that subjects actuating torques has demonstrated a better wearing performance in slope ...

A study is reported on the value of a modified KBM prosthesis compared with other types of prostheses. Recently a new type of below-knee prosthesis (the so called modified KBM prosthesis) was introduced in the Netherlands. This prosthesis is now frequently used as a substitute for more conventional types. A study was carried out on the value of this new prosthesis, compared with the more conven...

We undertook a study in which 138 female patients with a mean age of 71.2 years (51 to 82) received a standard NexGen CR-flex prosthesis in one knee and a gender-specific NexGen CR-flex prosthesis in the other. The mean follow-up period was 3.25 years (3.1 to 3.5). The aspect ratios of the standard and gender-specific prostheses were compared with that of the distal femur. The mean post-operati...

The length of the lower limb prosthesis was compared with the length of the contralateral lower extremity in 113 Finnish war-disabled amputees by a radiological weight bearing method developed by the author. Considering a shortening of 10 mm for above-knee prostheses and of 5 mm for below-knee prostheses as tolerance limits, the length of the prosthesis was acceptable only in 17 cases (15% of t...