PATIENT SPECIFIC INSTRUMENTATION WITH MEMS IN SURGERY

• US 20140031672A1
• Filed: 07/24/2013
• Published: 01/30/2014
• Est. Priority Date: 07/24/2012
• Status: Active Grant

• Current Assignee: Zimmer Incorporated (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Orthosoft Inc. (Zimmer Biomet Holdings, Inc.), Zimmer Incorporated (Zimmer Biomet Holdings, Inc.)
• Inventors: AMIOT, Louis-Philippe, McCaulley, Jeffrey A.
• Granted Patent: US 9,585,597 B2
• Time in Patent Office: Days
• US Class Current: 600/424
• CPC Class Codes: A61B 17/15 Guides therefor arrangements for guiding straight saw blades in general B23D51/025
• CPC Class Codes: A61B 2034/102 Modelling of surgical devices, implants or prosthesis
• CPC Class Codes: A61B 2034/105 Modelling of the patient, e.g. for ligaments or bones
• CPC Class Codes: A61B 2034/108 Computer aided selection or customisation of medical implants or cutting guides
• CPC Class Codes: A61B 2034/2048 using an accelerometer or inertia sensor
• CPC Class Codes: A61B 2505/05 Surgical care
• CPC Class Codes: A61B 34/20 Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
• CPC Class Codes: A61B 5/06 Devices, other than using radiation, for detecting or locating foreign bodies for removing same A61B17/50 ; determining position of probes within or on the body of the patient
• CPC Class Codes: A61B 5/1114 Tracking parts of the body
• CPC Class Codes: A61B 5/6878 Bone
• CPC Class Codes: A61B 6/032 Transmission computed tomography [CT]
• CPC Class Codes: A61B 6/505 for diagnosis of bone
• CPC Class Codes: G16H 50/50 for simulation or modelling of medical disorders

Abstract

An assembly of a patient specific instrument and tracking system comprises a patient specific instrument having a body with a patient specific contact surface negatively shaped relative to a corresponding surface of a bone for complementary contact therewith. An inertial sensor unit with a preset orientation is connected to the body in a planned connection configuration, such that a geometrical relation between the contact surface and the inertial sensor unit is known. A tracking system has a tracking processor connected to the inertial sensor unit, a user interface, and bone orientation data related to the patient specific contact surface, the tracking processor producing orientation tracking data for the bone using the geometrical relation and the bone orientation data when the preset orientation of the inertial sensor unit is initialized, to output the orientation tracking data on the user interface.

Claims

1. A method for creating a patient specific instrument model with an inertial sensor unit, comprising:

obtaining a patient specific bone model of at least part of a bone;

identifying at least one contact surface of the bone;

identifying orientation data related to the bone, a geometrical relation between the at least one contact surface and the orientation data being known;

generating a patient specific instrument model having at least one surface negatively corresponding to the at least one contact surface of the bone;

defining a connection configuration for an inertial sensor unit in the patient specific instrument model using said geometrical relation, the connection configuration relating a preset orientation of the inertial sensor unit to the orientation data of the bone; and

outputting the patient specific instrument model with the connection configuration for receiving the inertial sensor unit.

2. The method according to claim 1, wherein identifying orientation data related to the bone comprises identifying at least one axis of the bone.

3. The method according to claim 1, wherein identifying orientation data related to the bone comprises scanning the bone while in a known orientation relating the ground, identifying at least one axis of the bone, generating the patient specific bone model from the scanning, and relating the known orientation to the patient specific bone model.

4. The method according to claim 1, wherein defining a connection configuration comprises aligning an axis from the preset orientation of the inertial sensor unit with an axis of said orientation data.

5. The method according to claim 1, wherein outputting the patient specific instrument model comprises outputting a receptacle in the patient specific instrument model for receiving the inertial sensor unit in the connection configuration.

6. A method for tracking a bone with a patient specific instrument with an inertial sensor unit, comprising:

obtaining a patient specific instrument with an inertial sensor unit, the inertial sensor unit being preset with orientation data related to the bone;

placing the patient specific instrument on the bone by complementary contact between a surface of the bone and a negative patient specific surface of the patient specific instrument;

initializing the inertial sensor unit in the complementary contact to relate the orientation data to the bone; and

tracking the bone using data provided by the inertial sensor unit.

7. The method according to claim 6, wherein initializing the inertial sensor unit comprises aligning an axis of the orientation data of the inertial sensor unit with an axis of the bone obtained with the patient specific instrument.

8. The method according to claim 6, wherein obtaining a patient specific instrument with an inertial sensor unit comprises obtaining the patient specific instrument with the inertial sensor unit separately, and further comprising connecting the inertial sensor unit to the patient specific instrument in a known connector configuration.

9. An assembly of a patient specific instrument and tracking system comprising:

a patient specific instrument having a body with a patient specific contact surface negatively shaped relative to a corresponding surface of a bone for complementary contact therewith, and an inertial sensor unit with a preset orientation, the inertial sensor unit being connected to the body in a planned connection configuration, such that a geometrical relation between the contact surface and the inertial sensor unit is known; and

a tracking system having a tracking processor connected to the inertial sensor unit, a user interface, and bone orientation data related to the patient specific contact surface, the tracking processor producing orientation tracking data for the bone using the geometrical relation and the bone orientation data when the preset orientation of the inertial sensor unit is initialized, to output the orientation tracking data on the user interface.

10. The assembly according to claim 9, wherein the patient specific instrument comprises a tool interface in the body, with a geometrical relation between the tool interface and the inertial sensor unit being known.

11. The assembly according to claim 10, wherein the tool interface is one of a cut guide and a drill guide.

12. The assembly according to claim 9, wherein the bone orientation data is a file comprising at least one axis of the bone.

13. The assembly according to claim 9, wherein the body comprises a receptacle for releasably receiving the inertial sensor in the connection configuration.