Jig for determining a patient-adapted implant size of the femoral implant of a knee endoprosthesis

Abstract

A jig (1) for determining a patient-adapted implant size of the femoral implant of a knee endoprosthesis is disclosed, wherein the jig (1) has the following: a main body (2, 4), a probe part (7) movable relative to the main body (2, 4) along a measuring direction (6), wherein the probe part (7) has a probe arm (8) with a probe tip (9) for placing on an anterior reference point of the distal end of the patient's femur, two contact pieces (11, 12) for respectively placing on and referencing the medial and the lateral posterior condyle of the distal end of the patient's femur, and at least one scale (23, 24) and an associated pointer (21, 22) for indicating a position of the probe part (7) in the measuring direction (6) relative to at least one of the contact pieces (11, 12) for defining a suitable implant size. In order to avoid measurement errors of the kind that occur particularly when simultaneously defining the external implant angle using known jigs, the invention proposes that the contact pieces (11, 12) are movable relative to the main body (2, 4) in such a way that a distance, projected in the measuring direction (6), of the probe tip (9) from the contact pieces (11, 12) is adjustable for the contact pieces (11, 12) in such a way that this distance is different with respect to the two contact pieces (11, 12), and such that, for each contact piece (11, 12), a dedicated scale (23, 24) and an associated pointer (21, 22) are provided for the indication of a position of the probe part (7) in the measuring direction (6) relative to the respective contact piece (11, 12) and for the resulting indication of a suitable implant size.

Description

Technical field [0001] The present invention relates to a measuring tool for determining the implant size of a femoral implant suitable for a knee joint prosthesis of a patient, which has the characteristics according to claim 1. In this case, it is especially possible to use the measuring tool for primary care, that is, the primary care of a worn natural knee joint with a prosthesis. Background technique [0002] It is well known that knee joints damaged by wear or other phenomena (such as tumors) that are no longer able to perform normal, especially painless, movement for relevant patients can be replaced with corresponding implants as a Replacement of the articular surface of the related bones on the distal femur and the dorsal tibial side. To this end, various well-known suppliers have launched corresponding implants or implant series for daily use by relevant patients on the market. [0003] Based on the different anatomical conditions of the respective patients, different i...

AI Technical Summary

Problems solved by technology

[0016] The purpose of the present invention is to deal with errors and solve the problems associated with them

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