Back to results
US 12,514,714 B2Granted
Geared cam expandable interbody implant and method of implanting same
AssigneeWarsaw Orthopedic, Inc.
InventorsJonathan M. Dewey, William D. Armstrong
Life of this patent
Estimating the term…
Abstract
A geared cam expandable spinal implant. Rotational motion of a rotating portion is translated into linear motion of a yoke, which moves geared cams at the distal end of the implant to mate with, and walk along, teeth of corresponding racks. The walking of the gear cam teeth along the rack teeth creates a regular rate of implant expansion, reduces initial excessive expansion force applied to the implant, and provides fine adjustment of the expansion rate and force.
Claims20
An expandable spinal implant comprising:
- an upper endplate including an inner surface including an upper rack portion;
- a lower endplate including an inner surface including a lower rack portion;
- a chassis portion having a proximal end, a distal end, and an interior portion;
- a yoke being moveable with respect to the chassis portion, and having a proximal end and a distal end;
- a rotating portion including a cylindrical body mounted relative to the chassis portion, the rotating portion having an outer surface, a proximal end, and a distal end, the distal end being engaged to the yoke, and a portion of the outer surface being engageable with the interior portion of the chassis portion;
- and
- a first tooth and a second tooth rotatably mounted to the yoke, the first tooth being configured to movably engage with the upper rack portion, and the second tooth being configured to movably engage with the lower rack portion;
- wherein the rotating portion is further configured to transfer linear motion to the yoke upon rotation of the rotating portion, the yoke, being configured to expand the expandable spinal implant by translating linear motion of the yoke to rotational motion of the first tooth and second tooth to thereby move the upper endplate in a first direction, and the lower endplate in a second direction.
5 more elements
An expandable spinal implant comprising:
- a proximal end and a distal end defining a mid-longitudinal axis therebetween;
- an upper endplate including an inner surface including an upper rack portion;
- a lower endplate including an inner surface including a lower rack portion;
- a chassis portion having a proximal end, a distal end, and an interior portion positioned between the proximal end and the distal end of the chassis portion;
- a yoke movably mounted with respect to the chassis portion, and having a proximal end and a distal end;
- a rotating portion including a cylindrical body mounted relative to the chassis portion, the rotating portion having an outer surface, a proximal end, and a distal end, the distal end being engageable to the yoke, and the outer surface of the rotating portion being moveably engaged relative to the interior portion of the chassis portion;
- and
- a first tooth and a second tooth rotatably mounted relative to the yoke, the first tooth configured to movably engage with the upper rack portion, and the second tooth configured to movably engage with the lower rack portion;
- wherein the rotating portion is further configured to transfer linear motion to the yoke upon rotation of the rotating portion, the yoke translating the linear motion to rotational motion of the first tooth and the second tooth relative to the yoke;
- and
- wherein, to expand the expandable spinal implant, the rotation of the first tooth and interaction with the upper rack portion moves the upper endplate in a first direction, and the rotation of the second tooth and interaction with the lower rack portion moves the lower endplate in a second direction.
8 more elements
An expandable spinal implant comprising:
- a proximal end and a distal end defining a mid-longitudinal axis therebetween;
- an upper endplate including an inner surface including an upper rack portion;
- a lower endplate including an inner surface including a lower rack portion;
- a chassis portion mounted within the implant between the upper endplate and the lower endplate, the chassis portion having a proximal end, a distal end, an interior portion, the upper endplate and the lower endplate being pivotally attached relative to the chassis portion;
- a yoke movably mounted with respect to the chassis portion, and having a proximal end and a distal end;
- a rotating portion including a cylindrical body mounted relative to the chassis portion, the rotating portion having an outer surface, a proximal end, and a distal end, the distal end being positioned proximate the distal end of the yoke, and the outer surface being moveably engaged to the interior portion of the chassis portion;
- and
- a first tooth and a second tooth rotatably mounted relative to the yoke, the first tooth configured to movably engage with the upper rack portion, and the second tooth configured to movably engage with the lower rack portion;
- wherein the rotating portion is further configured to transfer linear motion to the yoke upon rotation of the rotating portion, the yoke translating the linear motion to rotational motion of the first tooth and the second tooth relative to the yoke that respectively pivots the upper endplate upwardly and the lower endplate downwardly to expand the expandable spinal implant.
6 more elements
Dependencies are inferred from the claim text.