Surgical instrument for shaping a bone

• US 5,387,218 A
• Filed: 02/23/1993
• Issued: 02/07/1995
• Est. Priority Date: 12/06/1990
• Status: Expired due to Fees

• Current Assignee: University College London (University of London)
• Original Assignee: University College London (University of London)
• Inventors: Meswania, Jayantilal M.
• Primary Examiner(s): Pellegrino, Stephen C.
• Assistant Examiner(s): Tucker, Guy V.
• Application Number:
  US07/910,017
• Time in Patent Office: 714 Days
• Field of Search: 606/80, 606/84, 606/85, 606/79, 606/86, 606/92, 606/95, 606/96, 606/99, 606/62, 606/60, 433/165, 433/166, 408/223, 408/224, 408/225, 408/227, 408/228
• US Class Current: 606/80
• CPC Class Codes: A61B 17/16 Bone cutting, breaking or removal means other than saws, e.g. Osteoclasts; Drills or chisels for bones; Trepans arthroscopic bone cutters A61B17/320016; dental implant drills potentially for other surgical use A61C8/0089; bone grinders A61F2/4644, A22C17/06; A61B17/1662 takes precedence over all other subgroups except A61B17/17
• CPC Class Codes: A61B 17/1631 Special drive shafts, e.g. flexible shafts A61B17/1642, A61B17/164 take precedence
• CPC Class Codes: A61B 17/1664 for the hip
• CPC Class Codes: A61B 17/175 for preparing the femur for hip prosthesis insertion
• CPC Class Codes: A61C 1/084 of implanting tools
• CPC Class Codes: A61C 3/02 Tooth drilling or cutting instruments; Instruments acting like a sandblast machine
• CPC Class Codes: A61C 8/0089 Implanting tools or instruments
• CPC Class Codes: A61F 2/3662 Femoral shafts
• CPC Class Codes: A61F 2/367 Proximal or metaphyseal parts of shafts trochanteric devices connected to said proximal parts A61F2/30739
• CPC Class Codes: B23D 77/00 Reaming tools

Abstract

An instrument for shaping a bone cavity has a frame (2) including a stud (5) for locating the instrument in a bone canal. A curved rod (1) is supported on the frame and a plurality of cutting teeth (18) are threaded on the rod so as to be rotatable thereon. The cutting teeth are drivably interconnected so that rotation of one tooth causes an adjacent tooth to rotate.

Claims

1. A surgical instrument for shaping a bone or cavity which comprises a curved rod whose curvature corresponds in one plane to that of a desired surface to be shaped for said bone or cavity, a plurality of cutting heads, each of which having a plurality of cutting surfaces, said cutting heads being individually and sequentially mounted on said rod lengthwise thereof so as to be rotatable thereon and to provide said cutting surfaces lengthwise of the rod, said cutting heads being drivably interconnected so that rotation of one of said heads causes a head adjacent to said one of said heads to rotate.

2. An instrument according to claim 1 wherein said curved rod is mounted in a frame, which includes a guide for location in or on a portion of said bone which serves as a reference surface, said guide limiting the depth of cut of the instrument.

3. An instrument according to claim 1 or 2 wherein the cutting heads are arranged as a continuous row and one end of the row is connected to a drive attachment for releasable connection to a driving means.

4. An instrument according to claim 1 wherein the teeth have lateral cutting surfaces.

5. An instrument according to claim 1 wherein said one head is drivably connected to the adjacent head by one or more projections extending lengthwise of the guide rod and which are engageable with one or more recesses in the adjacent head.

6. An instrument according to claim 5 wherein the or each projection engages in a corresponding recess in the adjacent head with a degree of play, so that the cutting heads together describe a helical-like path when they are rotated.

7. An instrument according to claim 5 wherein said heads are drivably connected to a driving means via a flexible drive.

8. An instrument for shaping a bone cavity which comprises a support rod, a curved guide rod whose curvature corresponds in one plane to that of a desired surface to be shaped for said bone mounted at one end on the support rod and extending generally at an acute angle thereto and a plurality of individual cutting heads mounted sequentially for rotation on said guide rod, each of said heads having lateral cutting surfaces and said heads being drivably interconnected so that rotation of one of said head causes a head adjacent said one of said heads to rotate and to ream an interior of the bone cavity.

9. An instrument according to claim 8 wherein the support rod has a stud portion which engages a hole in the bone cavity to stabilize the instrument while reaming the bone cavity.

10. An instrument according to claim 8 wherein the support rod includes a handle for stabilizing the instrument while reaming the bone cavity.