GLENOID IMPLANT SURGERY USING PATIENT SPECIFIC INSTRUMENTATION

• US 20150073424A1
• Filed: 03/28/2013
• Published: 03/12/2015
• Est. Priority Date: 03/28/2012
• Status: Active Grant

• Current Assignee: ORTHOsoft ULC. (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Orthosoft Inc. (Zimmer Biomet Holdings, Inc.)
• Inventors: Couture, Pierre, Richard, Alain, Abiven, Jean-Guillaume, Merette, Jean-Sebastien, Gourgon, Thomas
• Granted Patent: US 10,543,100 B2
• Time in Patent Office: Days
• US Class Current: 606/96
• CPC Class Codes: A61B 17/1684 for the shoulder
• CPC Class Codes: A61B 17/1778 for the shoulder
• CPC Class Codes: A61B 2017/568 produced with shape and dimensions specific for an individual patient
• CPC Class Codes: A61F 2/4081 Glenoid components, e.g. cups
• CPC Class Codes: A61F 2002/30736 Augments or augmentation pieces, e.g. wedges or blocks for bridging a bone defect
• CPC Class Codes: A61F 2002/4085 having a convex shape, e.g. hemispherical heads

Abstract

A pin placement instrument for placing a pin in a bone comprises an anatomical interface with a hook-like portion being opened in a lateral direction of the instrument to receive a bone therein in a planned position. A drill guide is connected to the anatomical interface and defining at least one guide slot in a longitudinal direction of the instrument. The guide slot has a lateral opening over its full length in the drill guide to allow lateral withdrawal of the instrument in said lateral direction with the pin placed in the bone passing through the lateral opening. A bushing is removably placed in said guide slot via said longitudinal direction in a planned fit, the bushing defining a throughbore aligned with the guide slot and adapted to receive the pin extending in said longitudinal direction when the bushing is in the guide slot for pin placement.

Claims

1. A pin placement instrument for placing a pin in a bone comprising:

an anatomical interface with a hook-like portion being opened in a lateral direction of the instrument to receive a bone therein in a planned position;

a drill guide connected to the anatomical interface and defining at least one guide slot in a longitudinal direction of the instrument, the at least one guide slot having a lateral opening over its full length in the drill guide to allow lateral withdrawal of the instrument in said lateral direction with the pin placed in the bone passing through the lateral opening; and

at least one bushing removably placed in said guide slot via said longitudinal direction in a planned fit, the bushing defining a throughbore aligned with the guide slot and adapted to receive the pin extending in said longitudinal direction when the bushing is in the guide slot for pin placement.

2. The pin placement instrument according to claim 1, wherein the drill guide comprises two of said guide slot.

3. The pin placement instrument according to claim 2, wherein the two said guide slots are parallel to one another.

4. The pin placement instrument according to claim 1, wherein the at least one bushing has an abutment end for limiting movement in the longitudinal direction when placed in the guide slot.

5. The pin placement instrument according to claim 1, further comprising a socket in the drill guide adapted to receive a handle for distal manipulation.

6. The pin placement instrument according to claim 1, further comprising at least one said pin for each set of the guide slot and the bushing, the bushing being in sliding engagement on the pin.

7. The pin placement instrument according to claim 1, wherein surfaces of the hook-like portion are generally transverse to the longitudinal direction.

8. The pin placement instrument according to claim 1, wherein the hook-like portion has at least one patient specific surface based on an anatomical model of the patient.

9. The pin placement instrument according to claim 8, wherein the anatomical model of the patient is that of a scapula, the at least one patient-specific surface being complementary to a shape of at least one of the scapula head and glenoid neck.

10. The pin placement instrument according to claim 9, wherein the at least one guide slot is longitudinally aligned with at least one of a planned center of an implant, a location adjacent to the superior glenoid rim in alignment with the coracoid, and a base of the coracoid.

11. A method for resurfacing a glenoid, comprising:

obtaining a patient specific instrument with at least two pin slots;

installing a pin slot of the patient specific instrument over a first pin secured to the scapula;

installing a cannulated reamer over a second pin secured to the glenoid;

installing a shaft slot of the patient specific instrument over a shaft of the cannulated reamer to form a joint between the shaft slot and the shaft of the cannulated reamer allowing a translational movement of the cannulated reamer along the second pin; and

reaming the glenoid using the cannulated reamer as guided by the patient specific instrument and the pins.

12. The method according to claim 11, wherein obtaining the patient specific instrument comprises obtaining the patient specific instrument with an end of the shaft slot distal from the glenoid at a patient specific distance from the glenoid, and further comprising stopping a reaming once a stopper on the shaft of the cannulated reamer abuts the end of the shaft slot.

13. The method according to claim 12, further comprising obtaining the cannulated reamer with the stopper on the shaft at a patient specific distance as a function of a planned depth of reaming.

14. The method according to claim 12, wherein installing the shaft slot of the patient specific instrument over the shaft of the cannulated reamer comprises rotating the patient specific instrument about the first pin for the shaft of the cannulated reamer to be received in the shaft slot via a lateral opening in the shaft slot.

15. A method for positioning an implant in a resurfaced glenoid cavity, comprising:

obtaining a patient specific instrument with at least one pin slot;

installing the pin slot of the patient specific instrument over a pin secured to the scapula;

installing a shaft of an impactor in a guide bracket of the patient specific instrument such that the shaft is aligned with the resurfaced glenoid cavity, a translational joint being formed between the shaft and the guide bracket allowing a translational movement of the shaft along the guide bracket;

installing the implant at the free end of the impactor; and

forcing the implant into the resurfaced glenoid cavity as guided by the patient specific instrument and the pin.

16. The method according to claim 15, obtaining a patient specific instrument comprises obtaining a patient specific orientation of the guide bracket such that an orientation of throughbores in the implant relative to the resurfaced glenoid cavity is as a function of planned positioning of screws received in the throughbores of the implant.

17. The method according to claim 15, further comprising positioning a drill guide in the implant forced into the resurfaced glenoid cavity, the drill guide comprising a visual pointer positioned to point toward the pin.

18. The method according to claim 15, wherein forcing the implant into the resurfaced glenoid cavity as guided by the patient specific instrument and the pin comprises moving the implant in a single translation degree of freedom.