Surgical equipment for implanting a total shoulder prosthesis, and total shoulder prosthesis constituting same

• US 6,228,120 B1
• Filed: 09/08/1999
• Issued: 05/08/2001
• Est. Priority Date: 01/09/1998
• Status: Expired due to Term

• Current Assignee: Exactech, Inc.
• Original Assignee: Alain Leonard, Pierre Flurin
• Inventors: Leonard, Alain, Flurin, Pierre
• Primary Examiner(s): Mancene, Gene
• Assistant Examiner(s): Priddy, Michael B.
• Application Number:
  US09/380,709
• Time in Patent Office: 608 Days
• Field of Search: 623/18.11, 623/19.11, 623/19.12, 623/19.13, 623/19.14
• US Class Current: 623/19.12
• CPC Class Codes: A61B 17/8808 with sealing collar for bone cavity
• CPC Class Codes: A61F 2/40 for shoulders
• CPC Class Codes: A61F 2/4014 Humeral heads or necks; Connections of endoprosthetic heads or necks to endoprosthetic humeral shafts
• CPC Class Codes: A61F 2/4059 Humeral shafts
• CPC Class Codes: A61F 2/4603 for insertion or extraction of endoprosthetic joints or of accessories thereof
• CPC Class Codes: A61F 2/4612 of shoulders
• CPC Class Codes: A61F 2/4637 for connecting or disconnecting two parts of a prosthesis
• CPC Class Codes: A61F 2/4684 Trial or dummy prostheses
• CPC Class Codes: A61F 2002/30143 hexagonal
• CPC Class Codes: A61F 2002/30224 cylindrical
• CPC Class Codes: A61F 2002/30332 Conically- or frustoconically-shaped protrusion and recess
• CPC Class Codes: A61F 2002/30378 Spherically-shaped protrusion and recess
• CPC Class Codes: A61F 2002/30433 using additional screws, bolts, dowels, rivets or washers e.g. connecting screws
• CPC Class Codes: A61F 2002/30492 using a locking pin
• CPC Class Codes: A61F 2002/30507 using a threaded locking member, e.g. a locking screw or a set screw
• CPC Class Codes: A61F 2002/30538 for adjusting angular orientation
• CPC Class Codes: A61F 2002/3054 about a connection axis or implantation axis for selecting any one of a plurality of radial orientations between two modular parts, e.g. Morse taper connections, at discrete positions, angular positions or continuous positions
• CPC Class Codes: A61F 2002/30604 modular
• CPC Class Codes: A61F 2002/30616 Sets comprising a plurality of prosthetic parts of different sizes or orientations
• CPC Class Codes: A61F 2002/30772 Apertures or holes, e.g. of circular cross section
• CPC Class Codes: A61F 2002/30785 : parallel
• CPC Class Codes: A61F 2002/30795 : Blind bores, e.g. of circular cross-section
• CPC Class Codes: A61F 2002/30797 : internally-threaded
• CPC Class Codes: A61F 2002/30808 : parallel
• CPC Class Codes: A61F 2002/3082 : Grooves
• CPC Class Codes: A61F 2002/30884 : Fins or wings, e.g. longitudinal wings for preventing rotation within the bone cavity
• CPC Class Codes: A61F 2002/30902 : laterally or radially
• CPC Class Codes: A61F 2002/4018 : Heads or epiphyseal parts of humerus
• CPC Class Codes: A61F 2002/4029 : Necks
• CPC Class Codes: A61F 2002/4037 : Connections of heads to necks
• CPC Class Codes: A61F 2002/4044 : Connections of necks to shafts
• CPC Class Codes: A61F 2002/4062 : Proximal or metaphyseal parts of shafts
• CPC Class Codes: A61F 2002/4077 : Distal or diaphyseal parts of shafts
• CPC Class Codes: A61F 2002/4627 : with linear motion along or rotating motion about the instrument axis or the implantation direction, e.g. telescopic, along a guiding rod, screwing inside the instrument
• CPC Class Codes: A61F 2002/4631 : the prosthesis being specially adapted for being cemented
• CPC Class Codes: A61F 2220/0025 : Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/0033 : made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2220/0041 : using additional screws, bolts, dowels or rivets, e.g. connecting screws
• CPC Class Codes: A61F 2230/0017 : Angular shapes
• CPC Class Codes: A61F 2230/0069 : cylindrical
• CPC Class Codes: A61F 2250/0006 : for adjusting angular orientation

Abstract

The invention concerns a surgical equipment provided with a total shoulder prosthesis comprising a hemispherical plate cap (20) and a prosthesis shank consisting of a humeral rod (1), a humeral plate (9) and a member (16) mutually locking the humeral rod and plate, with hemispherical contact surface (10a, 10b, 18) capable of allowing the humeral plate (9) of oscillating in all directions relative to the humeral rod (1), when the locking member (16) is in an unlocked position, and in locking the humeral rod and plate in the desired relative position.

Claims

1. A surgical device for the implantation of a total shoulder prosthesis, the device comprising:

a shoulder prosthesis stem with a humeral rod and a metaphysical section angled in relation to said humeral rod and presenting an upper frontal face centered on an axis and inclined in relation to the humeral rod;

said metaphysical section having a hemispherical cavity centered on said axis, and a tapped bore opening into the bottom of the hemispherical cavity and also centered on said axis;

a humeral plate comprising;

a hollow hemispherical ball joint having an axis of rotation and comprising an external face made to fit the cavity in the prosthesis stem and an internal face that defines a hemispherical bearing and has an axially drilled tapered bore;

a tapered swivel having an axis of rotation eccentric by a distance d in relation to the axis of rotation of the ball joint;

said tapered swivel being connected to the ball joint through a connecting section having a cross-section no larger than the maximum cross-section of said ball joint;

the tapered swivel and connecting section having a through hole drilled through them that extends into the extension of the cavity of the ball joint;

a locking unit comprising the following, arranged axially;

a rod having a threaded lower section and a diameter matching that of the tapped bore in the prosthesis stem and smaller than the minimum diameter of the tapered bore in the ball joint of the humeral plate;

a hemispherical ball joint made to fit the hemispherical portion of the ball joint of the humeral plate; and

a screw head for the locking unit;

the hemispherical cavity in the prosthesis stem, the external and internal faces of the ball joint in the humeral plate, and the ball joint of the locking unit being concentric around a point O when the locking unit is in locked position;

a head with a concave upper wall designed to fit a shoulder socket and a lower wall with a tapered housing having a shape that matches the tapered swivel; and

at least one trial head comprising a lower wall having the same size as that of the lower wall of the head with a tapered recess having a shape that matches that of the tapered swivel and an upper wall with a hole drilled therethrough that opens into said recess.

2. The surgical device according to claim 1, further comprising a gripper with a handle and a gripping head that is angled with respect to the handle;

said gripping head being designed to blank off the cavity in the metaphysical section of the prosthesis stem, and comprising;

a locking device with a threaded rod that screws into the tapped hole in the metaphysical section of the prosthesis stem;

a ring mounted around said gripping head that can oscillate around a swivel point O′

on the axis located at a distance from the bottom of the cavity in the prosthesis stem that is less than the distance between point O and the bottom of the cavity.

3. The surgical device according to claim 2, wherein the gripping head of the gripper comprises:

a hollow cap for covering the front face of the prosthesis stem;

said cap having an internal cavity forming a hemispherical bearing, an upper wall with an axially drilled hole, and a side wall with lengthwise oblong openings;

a ball joint housed in the internal cavity of the cap with an axially drilled hole of a diameter larger than that of the tapped bore of the prosthesis stem; and

connecting elements between the ball joint and the ring arranged so as to extend through the oblong openings in the cap and permit angular movements of said ball joint and ring;

the locking device comprising a screw with a shaft made to extend through the opening in the cap and the bore of the ball joint.

4. The surgical device according to claim 1, wherein the head and the cap have an axis of rotation eccentric by a distance d′

in relation to the axis of rotation of the tapered swivel of the humeral plate.

5. The surgical device according to claim 1, further comprising a set of humeral plates with connecting sections of various heights.

6. The surgical device according to claim 1, wherein the trial head has a knurled gripping head bounding the tapered recess that has an open upper wall and an external circular ring extending around a base of said knurled head.

7. A total shoulder prosthesis comprising in combination:

a shoulder prosthesis stem with a humeral rod and a metaphysical section angled in relation to said humeral rod, with an upper front face inclined in relation to the humeral rod;

said metaphysical section having a hemispherical cavity centered on an axis, and a tapped bore opening into the bottom of the hemispherical cavity and centering on the axis;

a humeral plate comprising;

a hollow hemispherical ball joint with an axis of rotation, with an external face designed to fit the cavity in the prosthesis stem and an internal face defining a hemispherical bearing, and perforated with an axially drilled tapered bore;

a tapered swivel having an axis of rotation eccentric by a distance d in relation to the axis of rotation of the ball joint, said tapered swivel being connected to the ball joint through a connecting section having a cross-section no larger than the maximum cross-section of said ball joint;

the tapered swivel and connecting section having a through hole drilled through them that extends into the extension of the cavity in the ball joint;

a locking unit comprising the following, arranged axially;

a rod having a threaded lower section and a diameter matching that of the tapped bore in the prosthesis stem and smaller than the median diameter of the tapered bore of the ball joint of the humeral plate;

a hemispherical ball joint made to fit the hemispherical part of the ball joint of the humeral plate; and

a screw head for said locking unit;

the hemispherical cavity in the prosthesis stem, the external and internal faces of the ball joint of the humeral plate, and the ball joint of the locking unit being concentric around a point O when the locking unit is in locked position; and

a head with a concave upper wall made to fit a shoulder glenoid cavity/glenoid component and a lower wall with a tapered recess whose shape matches the tapered swivel.

8. The total shoulder prosthesis according to claim 7, wherein the head has an axis of rotation eccentric by a distance d′

in relation to the axis of rotation of the tapered swivel of the humeral plate.