Navigated patella clamp

Patent metadata

Field	Value
Publication number	US-2017281202-A1
Application number	US-201615087202-A
Country	US
Kind code	A1
Filing date	Mar 31, 2016
Priority date	Mar 31, 2016
Publication date	Oct 5, 2017
Grant date	—

Abstract

Disclosed herein are systems and methods of patella arthroplasty. A navigated patella clamp used in an arthroplasty procedure includes first and second movable jaw members and an actuation member coupled to the first and second jaw members for moving the first and second jaw members along a plane toward and away from one another. The patella clamp further includes a tracker and adjustable stylus for positioning the clamp on a patient's patella below a desired resection plane. The adjustable stylus coupled to the clamp is used to check the position and orientation of the clamp with respect to the patella to ensure the correct amount of bone will be resected from the patella corresponding to the thickness of a patella component that will be implanted on the resected patella.

First claim

1 . A patella clamp comprising:
first and second jaw members; an actuation member coupled to the first and second jaw members for moving the first and second jaw members along a plane toward and away from one another; a tracker; and an adjustable stylus, wherein the tracker and adjustable stylus are coupled to the patella clamp, the adjustable stylus being both linearly and rotatably adjustable.

2 . The patella clamp of claim 1 , wherein the first and second jaw members each have at least one tooth for engaging a patella.

3 . The patella clamp of claim 1 , further comprising first and second parallel support members coupled to the actuation member and the first and second jaw members.

4 . The patella clamp of claim 1 , wherein the tracker is coupled to one of the first and second parallel support members.

5 . The patella clamp of claim 1 , wherein the tracker is capable of receiving and transmitting digital information, the digital information relating to a position and orientation of the patella clamp with respect to a patella.

6 . The patella clamp of claim 1 , wherein the adjustable stylus is coupled to one of the first and second jaw members.

7 . The patella clamp of claim 1 , wherein the adjustable stylus is coupled to one of the first and second jaw members via a post, the adjustable stylus being adjustable about the post.

8 . The patella clamp of claim 7 , wherein the post includes a plurality of grooves for adjusting the stylus about the post, each of the plurality of grooves corresponding to a height of the stylus from a determined resection plane.

9 . A method of defining a position of a navigated patella clamp on an unresected patella of a patient comprising:
displaying a three-dimensional model of the unresected patella of the patient on a graphics user interface; determining a position and orientation of a patella implant on the three-dimensional model, wherein an articular high point of the patella implant corresponds to an articular high point on the unresected patella and a patellar resection plane corresponds to a bone contacting surface of the patella implant; and defining the position of the patella clamp on the unresected patella by selecting on the three-dimensional model at least first and second jaw positions of the patella clamp each located superiorly to the patellar resection plane.

10 . The method of claim 9 , further comprising:
resecting the patella along the patellar resection plane; and positioning the bone contacting surface of the patella implant on the resected patella.

11 . The method of claim 9 , wherein a linear distance is defined by a line perpendicular to the patellar resection plane and passing through the articular high point, the linear distance corresponding to a maximum thickness of the patella implant.

12 . The method of claim 9 , wherein a plurality of bony landmarks are used to define the position and orientation of the patella implant on the bone model, the plurality of bone landmarks including peripheral cartilage borders located at medial, lateral and superior positions of the unresected patella.

13 . The method of claim 12 , wherein the peripheral cartilage borders and articular high point establish a coordinate system for positional alignment of the patellar implant.

14 . The method of claim 12 , wherein the plurality of landmarks are used to calculate and suggest a location and an orientation of the patellar resection plane on the model.

15 . The method of claim 9 , wherein the navigated patella clamp includes a tracker and an adjustable stylus.

16 . The method of claim 15 , further comprising engaging the unresected patella with the first and second jaws of the navigated patella clamp and a contact surface of the stylus.

17 . The method of claim 16 , wherein the first and second jaws engage the unresected patella adjacent peripheral cartilage borders.

18 . The method of claim 16 , wherein the contact surface of the stylus engages the articular high point of the unresected patella.

Assignees

• Howmedica Osteonics Corp

Inventors

• Hampp Emily
• Fossez John R
• Ferko Michael C

Classifications

• A61B34/20

  Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis · CPC title

• A61B2034/2072

  Reference field transducer attached to an instrument or patient · CPC title

• A61B17/1767 Primary

  for the patella · CPC title

• A61B17/158

  Cutting patella · CPC title

• A61B2090/3983

  Reference marker arrangements for use with image guided surgery · CPC title