Joint spacer

Abstract

The invention concerns a joint spacer, in particular a knee spacer and a hip spacer. In order to produce a long-lasting joint spacer which is sufficiently cushioned and abrasion-resistant and which can also support locally very high loads, the invention proposes a joint spacer having a Shore-A hardness of between 20 and 77 and tensile stress values at unit strain of between 20 % and 60 %, preferably 50 %, of greater than 3.8 N / mm2, preferably of greater than 4.6 N / mm2 and particularly preferably of greater than 6 N / mm2, and / or compressive stress values at linear compression of between 20 % and60 %, preferably 50 %, of greater than 7.8 N / mm2, preferably of greater than 9 N / mm2, and particularly preferably of greater than 10.5 N / mm2, and / or a Shore-A hardness of up to 85 and tensile stressvalues at unit strain of between 20 % and 60 %, preferably 50 %, of greater than 6 N / mm2, preferably of greater than 7 N / mm2, and particularly preferably of greater than 8 N / mm2, and / or compressive stress values at linear compression of between 20 % and 60 %, preferably 50 %, of greater than 10.5 N / mm2, preferably of greater than 12 N / mm2, and particularly preferably of greater than 14 N / mm2.

Description

[0001] This application is a divisional application of the application dated October 9, 2014, the application number is 201480067618.8, and the invention name is "joint gasket". technical field [0002] The present invention relates to a joint spacer, in particular a knee spacer and a hip spacer. [0003] Background of the invention [0004] Osteoarthritic disease, the premature wear and tear of cartilage joint surfaces, affects millions of people around the world, with the knee and hip joints being the hardest hit. As an alternative to previous artificial joints (endoprostheses), which had several disadvantages, we now offer elastic disc-shaped spacers, the "knee spacers". These spacers are implanted through a minimally invasive surgical incision after removal of the (residual) meniscus to level the articular surface and carefully select the appropriate size. In the joint, it replaces worn cartilage and damaged menisci. Knee spacers restore the natural joint space and, the...

AI Technical Summary

Problems solved by technology

Aromatic polyurethanes have various disadvantages compared to aliphatic polyurethanes, for example, they cause "yellowing" and thus show a certain degree of aging effect

In addition, aromatic polyurethanes are also controversial due to the potential carcinogenic risk of their degradation products

[0008] Knee spacers have not worked well in practice to date, as implants often break, slip out of the knee joint space, or limit motion

In particular, if a knee spacer with physiological damping is combined with sufficient mechanical and fatigue strength, etc., the results remain unknowable

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