US-20260124039-A1 - Expandable Spacer with Internal Expansion Actuator

US20260124039A1US 20260124039 A1US20260124039 A1US 20260124039A1US-20260124039-A1

Abstract

The description relates to an expandable intervertebral spacer configured to engage an intervertebral disk. An example expandable spacer includes a main body, a first endplate, a second endplate, a driving member, a plurality of pins, and an actuation member. The expandable spacer is configured to transition from a first configuration to a second configuration by various structures (e.g., steps, faceted surfaces, curved surfaces, multi-faceted portions) defined on the first endplate, the second endplate, and the driving member.

Inventors

Charles Lucasiewicz

Assignees

Degen Medical, Inc.

Dates

Publication Date: 20260507
Application Date: 20251107

Claims (10)

1 . An expandable spacer comprising: a terminal body defining a top groove and a threaded terminal aperture which further defines a central axis; a driving member defining a driving aperture, a first top rail and a first bottom rail; a bolt having both a headed portion and a threaded portion, the bolt being disposed within both the terminal body and the driving member; a top endplate defining a top endplate outer surface spaced apart from the central axis and having both a top tongue disposed within the top groove and a first top guide track in which the first top rail is disposed within, the first top guide track defining a first top ramp angle with respect to the central axis; and a bottom endplate having a first bottom guide track in which the first bottom rail is disposed within, wherein when the bolt is rotated, the headed portion of the bolt drives the top endplate along the first top ramp angle, increasing the space between the top endplate outer surface and the central axis.
2 . The spacer of claim 1 , wherein the terminal body further defines a bottom groove, wherein the bottom endplate further defines a bottom endplate outer surface spaced apart from the central axis and having a bottom tongue disposed within the bottom groove, and wherein the first bottom guide track further defines a first bottom ramp angle with respect to the central axis such that when the bolt is rotated, the headed portion of the bolt drives the bottom endplate along the first bottom ramp angle, increasing the space between the bottom endplate outer surface and the central axis.
3 . The spacer of claim 2 , wherein the top groove is integral with the bottom groove.
4 . The spacer of claim 2 , wherein an absolute value of first top ramp angle and the bottom ramp angle is the same such that when the bolt is rotated the rate of spatial increase between the top endplate outer surface and the central axis is the same as the rate of spatial increase between the bottom endplate and the central axis.
5 . The spacer of claim 2 , wherein an absolute value of the first top ramp angle and the bottom ramp angle is not the same such that when the bolt is rotated the rate of spatial increase between the top endplate outer surface and the central axis is not the same as the rate of spatial increase between the bottom endplate and the central axis.
6 . The spacer of claim 1 , wherein the top endplate outer surface further defines an endplate plane, wherein the endplate plane and the central axis define a plane angle, wherein the driving member further defines a second top rail spaced apart axial from the first top rail with respect to the central axis, wherein the top endplate further defines a second top guide track spaced apart axial from the first top guide track with respect to the central axis, in which the second top rail is disposed within the second top guide track, the second top guide track defining a second top ramp angle with respect to the central axis.
7 . The spacer of claim 6 , wherein an absolute value of the first top ramp angle and the second top ramp angle is the same such that when the bolt is rotated the plane angle remains the same.
8 . The spacer of claim 6 , wherein an absolute value of the first top ramp angle and the second top ramp angle is not the same such that when the bolt is rotated, the plane angle does not remain the same.
9 . The spacer of claim 1 , wherein the combination of the top endplate, the bottom endplate, and the driving member define a fluid channel generally perpendicular to the central axis.
10 . The spacer of claim 1 further comprising a washer configured to be disposed between the headed portion and the driving member.

Description

FIELD The disclosure relates to the field of implantable medical devices. More particularly, the disclosure relates to medical devices suitable for implantation in spaces between bones, such as spaces between vertebral bodies in a spinal column of a vertebrate or between other bones. Specific examples relate to expandable spacers suitable for implantation between adjacent vertebral bodies in a spinal column. The disclosure also relates to methods of making expandable spacers and methods of supplying expandable spacers. BACKGROUND Bone degeneration can be caused by trauma, disease, and natural processes, such as aging, which can have a negative impact on the lifestyle of an animal. For example, destabilization of a spine in a vertebrate, such as a human being, may result in alteration of the spacing between the adjacent vertebral bodies. This destabilization can place pressure onto the surrounding nerves and tissues between the vertebral bodies causing pain, discomfort, and, eventually, nerve damage. One approach to alleviating the pain and discomfort caused by the destabilization of the spacing between the adjacent vertebral bodies is to implant a medical device commonly referred to as an intervertebral spacer, or simply a spacer, into the space between two adjacent vertebral bodies. The intervertebral spacer supports the structure of the spine by maintaining a desired spacing between adjacent intervertebral bodies and proper angular positioning of the spinal column. Some intervertebral spacers are static devices that provide a spacer having fixed dimensions. Expandable intervertebral spacers are dynamic devices that allow for controlled expansion in situ. These expandable spacers provide several benefits, including reduction of the trialing required to identify and select an appropriate spacer for implantation and reduction of impaction of the adjacent vertebral bodies that can occur during insertion. Overall, expandable spacers offer a clinician an ability to optimize the fit of the spacer between intervertebral bodies during placement. Despite the existence of various expandable spacers in the art, a need for improved expandable intervertebral spacers remains. BRIEF SUMMARY OF SELECTED EXAMPLES An example is an expandable spacer. An expandable spacer includes a terminal body that defines a top groove and a threaded terminal aperture, which further defines a central axis. The spacer also comprises a driving member defining a driving aperture, a first top rail, and a first bottom rail. A bolt with both a headed portion and a threaded portion is disposed within the terminal body and the driving member. The top endplate features an outer surface spaced apart from the central axis and includes a top tongue disposed within the top groove. It also has a first top guide track in which the first top rail is disposed; this guide track defines a first top ramp angle with respect to the central axis. The bottom endplate includes a first bottom guide track in which the first bottom rail is disposed. When the bolt is rotated, the headed portion of the bolt drives the top endplate along the first top ramp angle, increasing the space between the top endplate outer surface and the central axis. DESCRIPTION OF FIGURES FIG. 1 is a perspective view of an example expandable spacer. The expandable spacer is shown in the first configuration. FIG. 2 is a perspective view of the example expandable spacer illustrated in FIG. 1. The expandable spacer is shown in the second configuration. FIG. 3 is a perspective view of the driving member disposed within the expandable spacer illustrated in FIG. 1. FIG. 4 is a perspective view of the top endplate presented in the expandable spacer illustrated in FIG. 1. FIG. 5 is a perspective view of the bottom endplate presented in the expandable spacer illustrated in FIG. 1. FIG. 6 is an exploded view of the example expandable spacer illustrated in FIG. 1. FIG. 7 is a top view of the example expandable spacer illustrated in FIG. 1. The expandable spacer is shown in the first configuration. FIG. 8 is a bottom view of the example expandable spacer illustrated in FIG. 1. The expandable spacer is shown in the first configuration. FIG. 9 is back view of the example expandable spacer illustrated in FIG. 1. The expandable spacer is shown in the first configuration. FIG. 10 is front view of the example expandable spacer illustrated in FIG. 1. The expandable spacer is shown in the first configuration. DESCRIPTION OF SELECTED EXAMPLES The following detailed description and the appended drawings describe and illustrate various example expandable spacers, example methods of making expandable spacers, and example methods of supplying expandable spacers. The description and drawings are provided to enable one skilled in the art to make and use one or more example expandable spacers. They are not intended to limit the scope of the claims in any manner. Each of FIGS. 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10 illustrate