# US 11,304,729 B2 · Non-invasive adjustable distraction system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,304,729 B2 - Document ID: US11304729B2 - Status: Granted - Kind: B2 - Application number: 16/678,977 - Filed: 2019-11-08 - Published: 2020-03-05 - Granted: 2022-04-19 - Earliest claimed: 2009-02-23 - Assignees: Nuvasive Specialized Orthhopedics, Inc. - Applicants: NuVasive Specialized Orthopedics, inc. - Inventors: Scott Pool; Blair Walker - Web page: https://patentgrep.com/patent/US11304729B2 ## CPC - A61B 17/7004: {with a cross-section which varies along its length (A61B17/7019 takes precedence)} - A61B 17/7016: {electric or electromagnetic means} - A61B 17/7019: {Longitudinal elements having flexible parts, or parts connected together, such that after implantation the elements can move relative to each other} - A61B 17/707: {Devices acting on, or attached to, a transverse process or rib; Tools therefor} - A61B 17/7216: {for bone lengthening or compression (A61B17/7258 takes precedence)} - A61B 17/7011: {Longitudinal element being non-straight, e.g. curved, angled or branched (adjustable length longitudinal elements A61B17/7014; A61B17/7019 takes precedence, e.g. coil springs)} - A61B 2017/00199: {with a console, e.g. a control panel with a display} - A61B 2017/00212: {using remote controls} - A61B 2017/00411: {actuated by application of energy from an energy source outside the body} - A61B 2017/00876: {magnetic} - A61B 2017/681: {Alignment, compression, or distraction mechanisms} - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract A spinal distraction system includes a distraction rod having a first end and a second end, the first end being configured for affixation to a subject's spine at a first location, the distraction rod having a second end containing a recess having a threaded portion disposed therein. The system further includes an adjustable portion configured for affixation relative to the subject's spine at a second location remote from the first location, the adjustable portion comprising a housing containing a magnetic assembly, the magnetic assembly affixed at one end thereof to a lead screw, the lead screw operatively coupled to the threaded portion. A locking pin may secure the lead screw to the magnetic assembly. An O-ring gland disposed on the end of the housing may form a dynamic seal with the distraction rod. ## Claims ### Claim 1 A spinal distraction system comprising: a distraction rod having a first end configured for affixation to a subject's spine at a first location and a second end containing a recess having a threaded portion disposed therein; and an adjustable portion configured for affixation to the subject's spine at a second location remote from the first location, the adjustable portion comprising: a lead screw, a housing extending along a longitudinal axis, the housing containing a permanent magnet and the lead screw, wherein the housing contains the permanent magnet in close proximity to a first end of the housing, and wherein the permanent magnet is configured to rotate the lead screw about the longitudinal axis within the housing, the lead screw being operatively coupled to the threaded portion of the distraction rod, and wherein the housing further includes an open end at a second end that is opposite the first end, and a locking pin passing transversely through the lead screw configured to couple the permanent magnet to the lead screw to permit angular displacement of the lead screw relative to the magnet within the housing, wherein upon rotating the lead screw by the permanent magnet, the lead screw is configured to communicate with the threaded portion of the distraction rod to telescopically move the distraction rod into and out of the open end of the housing of the adjustable portion and change an axial length of the spinal distraction system. ### Claim 2 (depends on 1) The spinal distraction system of claim 1, wherein the locking pin comprises heat treated stainless steel. ### Claim 3 (depends on 1) The spinal distraction system of claim 1, comprising a magnet assembly having a first cup and a second cup with the permanent magnet located in a recess formed between the first cup and the second cup. ### Claim 4 (depends on 3) The spinal distraction system of claim 3, the first cup comprising a receptacle having an aperture dimensioned to receive the locking pin. ### Claim 5 (depends on 4) The spinal distraction system of claim 4, further comprising a bearing disposed within the housing of the adjustable portion. ### Claim 6 (depends on 4) The spinal distraction system of claim 4, wherein the receptacle is dimensioned to permit angular displacement of the lead screw relative to a longitudinal axis of the magnetic assembly. ### Claim 7 (depends on 1) The spinal distraction system of claim 1, comprising at least one O-ring dimensioned to form a fluid tight seal between the housing and the distraction rod. ### Claim 8 (depends on 7) The spinal distraction system of claim 7, wherein the at least one O-ring has a compression value that ranges from 13% to 18%. ### Claim 9 (depends on 7) The spinal distraction system of claim 7, wherein the at least one O-ring is coated with a lubricant. ### Claim 10 (depends on 7) The spinal distraction system of claim 7, wherein the fluid tight seal comprises an air tight seal. ### Claim 11 (depends on 10) The spinal distraction system of claim 10, wherein an interior between the housing and the distraction rod has a positive air pressure configured to permit movement of the distraction rod while sealing the interior of the housing. ### Claim 12 (depends on 7) The spinal distraction system of claim 7, further comprising an external adjustment device and wherein the lead screw is configured to rotate in a first direction to increase the axial length of the spinal distraction system and configured to rotate in a second opposite direction to decrease the axial length of the spinal distraction system. ### Claim 13 (depends on 1) The spinal distraction system of claim 1, the housing comprising a stop in close proximity to the open end, and the distraction rod comprising a splined tip, the stop of the housing configured to prevent the splined tip of the distraction rod from exiting the housing, and thereby maintaining the distraction rod with respect to the housing. ### Claim 14 (depends on 1) The spinal distraction system of claim 1, wherein the permanent magnet comprises a cylindrical magnet. ### Claim 15 (depends on 1) The spinal distraction system of claim 1, the threaded portion bonded to the distraction rod by an adhesive material. ### Claim 16 (depends on 15) The spinal distraction system of claim 15, the threaded portion comprising a material that is different from the material of the lead screw. ### Claim 17 (depends on 16) The spinal distraction system of claim 16, the threaded portion comprising a softer material than the material of the lead screw. ### Claim 18 (depends on 17) The spinal distraction system of claim 17, the lead screw comprising titanium. ### Claim 19 (depends on 17) The spinal distraction system of claim 17, the lead screw comprising aluminum bronze.