ABSTRACT
Objective To study the effects of prosthetic alignment on internal contact mechanical characteristics of intact knee joint for transfemoral amputees. Methods The gait experiment of transfemoral amputees was performed under different alignment conditions, and the differences of lower limb motion and ground reaction force (GRF) were analyzed and compared with those of the non-amputees. The three-dimensional （30） finite element model of knee joint was build and used to analyze the effect of alignments of socket adduction and abduction on internal contact mechanical characteristics between femur cartilage, tibia cartilage and meniscus. Results For knee joint of the non-amputees, contact force was mainly concentrated on the medial sides at the moment of the first GRF peak, while contact force was mainly concentrated on the lateral sides at the moment of the second GRF peak. However, for intact knee joint of the transfemoral amputees, contact force was mainly concentrated on the medial side at the moment of two GRF peaks. The stress of the medial meniscus, contact force and contact area between the medial meniscus and cartilage all obviously increased under the alignment of 6° socket adduction. Conclusions Compared with non-amputees, the incidence of knee osteoarthritis (OA) in amputees was higher, which was related to the long-term overload of the medial knee joint. The alignment of socket adduction may increase the risk of knee OA in the intact side of transfemoral amputees. In clinic, excessive adduction of the socket should be avoided during prosthetic alignment.
ABSTRACT
Objective To compare the walking abilities of an unilateral transfemoral amputee with four different prosthetic knee joints, to provide a reference for clinical prosthetic prescription. Methods An unilateral transfemoral amputee was asked to wear four kinds of pros-thetic knee joints, mechanical four-bar, pneumatic four-bar, hydraulic and intelligent prosthetic knee joints, and evaluated with Timed Up and Go Test, indoor 6-Minute Walk Test, Static Stand Balance Test and a 1000-meter Outdoor Walking Ability Test, wearing Intelligent De-vice for Energy Expenditure and Activity. Results The amputee consumed the least energy and walked the fastest with intelligent prosthetic knee joint. Conclusion There are some difference in walking ability with different prosthetic knee joints.
ABSTRACT
Objective To compare the walking abilities of an unilateral transfemoral amputee with four different prosthetic knee joints, to provide a reference for clinical prosthetic prescription. Methods An unilateral transfemoral amputee was asked to wear four kinds of pros-thetic knee joints, mechanical four-bar, pneumatic four-bar, hydraulic and intelligent prosthetic knee joints, and evaluated with Timed Up and Go Test, indoor 6-Minute Walk Test, Static Stand Balance Test and a 1000-meter Outdoor Walking Ability Test, wearing Intelligent De-vice for Energy Expenditure and Activity. Results The amputee consumed the least energy and walked the fastest with intelligent prosthetic knee joint. Conclusion There are some difference in walking ability with different prosthetic knee joints.
ABSTRACT
OBJECTIVE: The aim of this study was to investigate the characteristics of prosthetic gait of unilateral transfemoral amputees on an inclined surface compared with those of normal persons. METHOD: Five male unilateral transfemoral amputees and ten normal persons were recruited. Uphill and downhill walking of inclined surface on slopes of 10 and 20 degrees and level walking were investigated. Kinematic data were obtained with VICON 370 system (Oxford Metrics Ltd., UK). RESULTS: The kinematic data of the transfemoral amputees showed significantly decreased peak hip extension at all situation and peak hip flexion at 20 degrees uphill walking, significant increased knee extension at 20 degrees downhill and all uphill walking, and significant decreased knee flexion at all situation, and significant decreased ankle dorsiflexion at all situation and plantarflexion at all situation except 20 degrees downhill walking compared with those of normal persons. Also they showed significant decreased cadence, speed and increased step time, double support at all situation compared with normal persons. CONCLUSION: Analysis of prosthetic gait of unilateral transfemoral amputees on an inclined surface support the basic data for induction of normal gait pattern.