Polycentric above-knee prosthesis

摘要

The new polycentric above-knee prosthesis having a closed kinematic four-bar mechanism avoids advancement of the knee relative to the lower leg on bending forward, has an improved cosmetic appearance in the bent state, manages without clamping sleeves and adjustment adapters despite being fully adjustable in the sagittal plane, is produced with relatively small construction costs, is lighter than polycentric solutions, can be controlled more easily by the stump forces that are still present, lifts the tip of the foot in the swing-through phase and can be produced in shell design or skeleton design with foam lining (48). These properties are achieved in that the upper coupling is formed, as previously, by the knee member (1), whereas the lower coupling is formed by the foot moulding itself, so that the upper two axes (2, 3) are allocated to the knee member (1) and the lower two axes (5, 7) are allocated to the foot moulding (6). The front link (8, 45) forms the lower leg and receives the rear link (4) in a cavity (8b). The rear link extends between the rear hinge point (3) of the knee member (1) and the rear hinge point (5) of the foot, and the upper rear hinge point (3) is arranged on a straight line extending obliquely downwards by 40 to 50 degrees from the front upper hinge point (2). <IMAGE>