# US 2008/0188878 A1 · Osteotome > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2008/0188878 A1 - Document ID: US20080188878A1 - Status: Published application - Kind: A1 - Application number: 11/792,198 - Filed: 2005-12-02 - Published: 2008-08-07 - Earliest claimed: 2004-12-02 - Assignees: Orthosonics Limited - Inventors: Michael John Radley Young - Web page: https://patentgrep.com/patent/US20080188878A1 ## CPC - A61B 17/16: Instruments for performing osteoclasis; Drills or chisels for bones; Trepans {(arthroscopic bone cutters A61B17/320016)} - A61B 17/142: {with reciprocating saw blades, e.g. with cutting edges at the distal end of the saw blades} - A61B 17/144: {with cutting edges at the side of the saw blades} - A61B 17/1628: {Motors; Power supplies} - A61B 17/1637: {Hollow drills or saws producing a curved cut, e.g. cylindrical (A61B10/025, A61B17/1695 take precedence)} - A61B 17/1642: {for producing a curved bore} - A61B 17/1664: {for the hip} - A61B 2017/320077: {double edge blade, e.g. reciprocating} - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract A tool (1, 31) for cutting bone comprises an elongate blade (7,37) connectable to a generator of longitudinal-mode ultrasonic vibrations. The blade (7,37) has two lateral cutting edges (9,10) linked by a rounded distal tip (8). A series of triangular teeth (13) extends along each cutting edge (9,10) and the distal tip (8). The blade (37) may taper towards each cutting edge (9,10) and the distal tip (8). A variant of the tool (21) comprises an elongate part-cylindrical blade (27) connectable to a generator of torsional-mode ultrasonic vibrations. The blade (27) has a cutting edge at its distal tip (28) provided with a plurality of triangular teeth (23). All forms of the tool (1, 21, 31) are particularly suitable for cutting cancellous bone around an implant to be removed during revision of a joint arthroplasty. ## Claims ### Claim 1 A tool adapted to cut bone comprising: means for generating ultrasonic vibrations, and an elongate blade operatively connectable thereto, the blade having at least one cutting edge provided with a plurality of serrations each having a first cutting facet substantially transverse to the direction of said ultrasonic vibrations. ### Claim 2 (depends on 1) A tool as claimed in claim 1, wherein the means for generating ultrasonic vibrations produces longitudinal mode ultrasonic vibrations directed substantially parallel to a longitudinal axis of the blade. ### Claim 3 (depends on 1) A tool as claimed in claim 1, wherein the blade comprises an elongate substantially planar member having two substantially oppositely-facing lateral edges. ### Claim 4 (depends on 3) A tool as claimed in claim 3, wherein said oppositely-facing lateral edges each extend substantially parallel to the longitudinal axis of the blade. ### Claim 5 (depends on 3) A tool as claimed in claim 3, wherein the elongate member further comprises a rounded distal tip extending between a distal end of a first of said oppositely-facing lateral edges and a distal end of a second of said oppositely-facing lateral edges. ### Claim 6 A tool as claimed in 5, wherein the at least one cutting edge extends along at least part of a respective one of said oppositely-facing lateral edges. ### Claim 7 (depends on 6) A tool as claimed in claim 6, wherein the at least one cutting edge extends around all or part of the rounded distal tip. ### Claim 8 (depends on 3) A tool as claimed in claim 3, wherein at least part of the blade has a cross-sectional profile tapering towards one or each of said oppositely-facing lateral edges. ### Claim 9 (depends on 5) A tool as claimed in claim 5, wherein the blade has a cross-sectional profile adjacent its distal tip tapering towards said distal tip. ### Claim 10 (depends on 1) A tool as claimed in claim 1, wherein each serration of the plurality of serrations is generally triangular. ### Claim 11 (depends on 1) A tool as claimed in claim 1, wherein each serration of the plurality of serrations has its first cutting facet extending generally orthogonally to a local alignment of the cutting edge. ### Claim 12 (depends on 1) A tool as claimed in claim 1, whereas the means for generating ultrasonic vibrations produces torsional mode ultrasonic vibrations. ### Claim 13 (depends on 12) A tool as claimed in claim 12, wherein the blade comprises an elongate member having a curved cross-section substantially comprising an arc of a circle. ### Claim 14 (depends on 13) A tool as claimed in claim 13, wherein said tool is adapted to be torsionally vibratable about a longitudinal axis extending through the centre of said circle. ### Claim 15 (depends on 13) A tool as claimed in claim 13, wherein a distal tip of the elongate member comprises the at least one cutting edge. ### Claim 16 (canceled) ### Claim 17 A method of cutting bony material comprising the steps of: providing a tool comprising: means for generating ultrasonic vibrations, and an elongate blade operatively connectable thereto, the blade having at least one cutting edge provided with a plurality of serrations each having a first cutting facet substantially transverse to the direction of said ultrasonic vibrations, applying said at least one cutting edge of the tool to a surface of bony material to be cut, causing the tool to vibrate at an ultrasonic frequency by actuating the means for generating ultrasonic vibrations, and drawing the cutting edge of the tool across said surface.