Patent ID: 7597716

Claim:
A knee joint prosthesis with a first body associated with the thigh and a second body associated with the lower leg, which engages around the first body in fork fashion, whereby arched guiding elements with a variable curvature are provided in the first body, into which engage bolts of the like of the second body wherein in each of the limbs of the fork-shaped first body two guiding elements with a variable curvature are provided, whereby in each case a bolt or the like of the second body engages into each of the guiding elements, and the points X P (φ), Y p (φ) of the first guiding element and the points X Q (φ), Y Q (φ) of the other guiding element correspond approximately to the following equations: X P (φ)= A 1*φ 5 +B 1*φ 4 +C 1*φ 3 +D 1*φ 2 +E 1*φ− F 1 Y P (φ)= A 1*φ 5 +B 1*φ 4 +C 1*φ 3 +D 1*φ 2 +E 1*φ− F 1 X Q (φ)= A 1*φ 5 +B 1*φ 4 +C 1*φ 3 +D 1*φ 2 +E 1*φ− F 1 Y Q (φ)= A 1*φ 5 +B 1*φ 4 +C 1*φ 3 +D 1*φ 2 +E 1*φ− F 1 whereby the deflection angle of the knee joint is indicated in radians, the points X P (φ), Y P (φ) of the first guiding element and the points X Q (φ), Y Q (φ) of the other guiding element corresponding approximately to the following equations: X P (φ)=2.5468φ 5 −13.3577φ 4 +27.2734φ 3 −25.0789φ 2 −14.3902φ−0.0195 Y P (φ)=−2.0355φ 5 +8.4168φ 4 −11.4013φ 3 +0.3239φ 2 +5.5098φ+0.0201 X Q (φ)=2.6774φ 5 −12.9957φ 4 +21.7884φ 3 −24.8599φ 2 +15.9312φ−0.0179 Y Q (φ)=−1.8306φ 5 +6.7402φ 4 −10.9995φ 3 +15.3202φ 2 +5.5433φ−30.3853 where the deflection angle φ of the knee joint is indicated in radians.