US 6,915,150 B2 · Process and device for the preoperative determination of the positioning data of endoprosthetic parts

Abstract

In order to be able to ascertain the position of the bone in the body without complicated procedures in a process for the preoperative determination of the positioning data of endoprosthetic parts of a central joint relative to the bones forming the central joint, a respective outer articular point is determined by way of movement of the bones about a respective outer joint which is located at the end of the two bones facing away from the central joint. An articular point is determined for each of the two bones in the area of the central joint, and a direction characteristic for each of these bones is determined by way of a straight-line connection of the two articular points obtained in this manner for the two bones. The orientation of the endoprosthetic parts relative to this characteristic direction is then determined. Apparatus for carrying out the process is also provided.

Claims45

Dependent claims

A method for the preoperative determination of positioning data of an endoprosthetic part of a knee joint relative to a thigh bone and a lower leg bone forming the knee joint, comprising the steps of:

moving the thigh bone of the knee joint relative to a corresponding hip bone while determining the positions of the thigh bone and the hip bone, to determine a first articular point for said thigh bone in the area of the hip;
the thigh and hip bone positions being determined by securely connecting marking elements to said bones and determining the respective positions of the marking elements using a measuring device that provides signals corresponding to the respective positions to a data processing system;
determining a second articular point for said thigh bone in the area of the knee joint;
determining a first characteristic direction for said thigh bone by way of a straight-line connection of the first and second articular points;
and
determining an orientation of the endoprosthetic part relative to the first characteristic direction.

3 more elements

A device for the preoperative determination of positioning data of endoprosthetic parts of a knee joint relative to a thigh bone and a lower leg bone forming the knee joint, comprising:

at least one marking element securable to the thigh bone and at least one marking element securable to a hip bone, said thigh bone and said hip bone being connected at a hip joint;
a measuring device for determining the position of the marking elements in space;
and
a data processing system adapted to receive signals corresponding to positioning data of the marking elements from the measuring device;
wherein:
said data processing system is responsive to the signals during movement of the thigh bone relative to the hip bone to determine the point of greatest invariance at the hip joint as a first articular point;
a second articular point is determined for said thigh bone in the area of the knee joint;
and
a first characteristic direction is determined for the thigh bone from the positions of the first articular point and the second articular point.

6 more elements

Dependencies are inferred from the claim text.

Process and device for the preoperative determination of the positioning data of endoprosthetic parts

Life of this patent

Process and device for the preoperative determination of the positioning data of endoprosthetic parts

Life of this patent

Abstract

Claims45