# US 11,439,443 B2 · Rod reducing device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,439,443 B2 - Document ID: US11439443B2 - Status: Granted - Kind: B2 - Application number: 16/655,421 - Filed: 2019-10-17 - Published: 2020-02-13 - Granted: 2022-09-13 - Earliest claimed: 2017-01-18 - Assignees: K2M, Inc. - Applicants: K2M, Inc. - Inventors: Kan Min; Brian Kunes - Web page: https://patentgrep.com/patent/US11439443B2 ## CPC - A61B 17/7086: {Rod reducers, i.e. devices providing a mechanical advantage to allow a user to force a rod into or onto an anchor head other than by means of a rod-to-bone anchor locking element; rod removers} - A61B 17/7002: {Longitudinal elements, e.g. rods} - A61B 17/7091: {for applying, tightening or removing longitudinal element-to-bone anchor locking elements, e.g. caps, set screws, nuts or wedges} - A61B 17/7032: {Screws or hooks with U-shaped head or back through which longitudinal rods pass} - A61B 17/7041: {with single longitudinal rod offset laterally from single row of screws or hooks (A61B17/7044 takes precedence)} - A61B 17/7085: {for insertion of a longitudinal element down one or more hollow screw or hook extensions, i.e. at least a part of the element within an extension has a component of movement parallel to the extension's axis} - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract A rod reducer includes a housing, an anvil, a locking anvil configured to engage a locking plug of a bone screw assembly, an arm assembly, a reducing screw extending through the housing and rotatably coupled with the anvil, and a locking screw extending through the housing and rotatably coupled with the locking anvil. The arm assembly includes an arm hingedly coupled to the housing, and first and second grasping members configured to engage the bone screw assembly. The first and second grasping members are hingedly coupled to the housing and extend through the anvil. Rotation of the reducing screw transitions the arm assembly between an open position, in which, distal portions of the arm and the first and second grasping members are radially expanded, and a closed position, in which, the distal portions of the arm and the first and second grasping members are radially contracted. ## Claims ### Claim 1 A method of reducing a spinal rod comprising: transitioning a rod reducer to an open state, in which, distal ends of a first arm and grasping members of the rod reducer are radially expanded; positioning the rod reducer over a bone screw assembly; positioning a spinal rod adjacent a rod receiving portion of the bone screw assembly; rotating a reducing screw of the rod reducer to transition an anvil of the rod reducer away from a housing of the rod reducer to a closed state, in which, the distal ends of the first arm and the grasping members of the rod reducers are radially contracted to engage the bone screw assembly; reducing the spinal rod into the rod receiving portion; and rotating a locking screw of the rod reducer to move a locking anvil to advance a locking plug into a bone screw housing of the bone screw assembly to secure the spinal rod to the rod receiving portion, the locking screw and the locking anvil being rotatably coupled to one another. ### Claim 2 (depends on 1) The method of claim 1, wherein rotating the reducing screw of the rod reducer includes engaging the first arm of the rod reducer with the rod receiving portion of the bone screw assembly. ### Claim 3 (depends on 2) The method of claim 2, wherein rotating the reducing screw of the rod reducer includes engaging the grasping members with the bone screw housing of the bone screw assembly. ### Claim 4 (depends on 2) The method of claim 2, wherein the reducing screw is rotatably coupled with the anvil. ### Claim 5 (depends on 1) The method of claim 1, further comprising partially rotating the locking screw to partially advance the locking plug into the bone screw housing of the bone screw assembly and making adjustments to the spinal rod. ### Claim 6 (depends on 1) The method of claim 1, wherein rotation of the locking screw causes axial displacement of the locking anvil relative to the anvil. ### Claim 7 (depends on 1) The method of claim 1, wherein the locking anvil imparts an axial force to the locking plug to transition the housing of the bone screw assembly to a locked state. ### Claim 8 (depends on 1) The method of claim 1, wherein the locking anvil advances within a cutout of the anvil. ### Claim 9 (depends on 1) The method of claim 1, wherein when the locking screw is rotated, the locking screw threadably engages a threaded bore of the anvil. ### Claim 10 A method of reducing a spinal rod comprising: positioning a rod reducer over a bone screw assembly; positioning a spinal rod adjacent a rod receiving portion of the bone screw assembly; transitioning an anvil of the rod reducer to transition a first arm and grasping members of the rod reducer from a radially expanded position to a closed position, in which, the first arm and the grasping members of the rod reducers are radially contracted to engage the bone screw assembly; reducing the spinal rod into the rod receiving portion; and rotating a locking screw of the rod reducer to move a locking anvil to advance a locking plug into a bone screw housing of the bone screw assembly to secure the spinal rod to the rod receiving portion, the locking screw and the locking anvil being rotatably coupled to one another. ### Claim 11 (depends on 10) The method of claim 10, wherein the step of transitioning the anvil includes rotating a reducing screw of the rod reducer. ### Claim 12 (depends on 10) The method of claim 10, further comprising partially advancing the locking plug into the bone screw housing of the bone screw assembly and making adjustments to the spinal rod. ### Claim 13 (depends on 10) The method of claim 10, wherein the reducing step includes rotating a reducing screw of the rod reducer. ### Claim 14 (depends on 13) The method of claim 13, wherein the locking screw and the locking anvil are rotatably coupled together. ### Claim 15 (depends on 10) The method of claim 10, wherein rotating the reducing screw of the rod reducer includes engaging the first arm of the rod reducer with the rod receiving portion of the bone screw. ### Claim 16 (depends on 15) The method of claim 15, wherein rotating the reducing screw of the rod reducer includes engaging the grasping members with the bone screw housing of the bone screw assembly. ### Claim 17 (depends on 10) The method of claim 10, wherein the locking anvil advances within a cutout of the anvil. ### Claim 18 A method of reducing a spinal rod comprising: transitioning a rod reducer to an open state, in which, distal ends of a first arm and grasping members of the rod reducer are radially expanded; positioning the rod reducer over a bone screw assembly; positioning a spinal rod adjacent a rod receiving portion of the bone screw assembly; rotating a reducing screw of the rod reducer to transition an anvil of the rod reducer away from a housing of the rod reducer to a closed state, in which, the distal ends of the first arm and the grasping members of the rod reducers are radially contracted, the grasping members engage the bone screw housing of the bone screw assembly, and the first arm of the rod reducer engages the rod receiving portion of the bone screw assembly; reducing the spinal rod into the rod receiving portion; and rotating a locking screw of the rod reducer to axially move a locking anvil relative to the anvil to advance a locking plug into a bone screw housing of the bone screw assembly to transition the housing of the bone screw assembly to a locked state to secure the spinal rod to the rod receiving portion, the locking screw and the locking anvil being rotatably coupled to one another.