Implants for tissue fixation and fusion

Inventors

Kuntz, Kyle • Patel, Shyam

Assignees

Cutting Edge Spine LLC

Abstract

A fixation implant includes a head, a shank and a distal tip, and one or more of the head, shank and distal tip may be cannulated. The shank includes a threaded ingrowth portion extending from the head to the tapered distal tip that includes external threads, and at least one open network body extending along the length of the ingrowth portion. The open network body selected from one or a combination of a helix, an arrangement of trusses, a scaffold of open and interconnected pores, a porous framework of random open and interconnected pores, and combinations of these.

Core Innovation

The invention relates to an orthopedic fixation implant having an implant head with a tool recess for engagement with a driving instrument, and a threaded shank with a tapered self-tapping distal tip. The implant includes external threads, with a non-porous first threading along an external surface of the shank and a non-porous second threading along an external surface of the head, and the implant geometry constrains outer diameter relationships between the head and the shank while maintaining a consistent maximum outer diameter along the shank from a proximal end to a distal end.

At least a portion of the shank, and optionally one or more of the tip or the head, comprises an open network body with a scaffold of open and interconnected pores mimicking a trabecular bone structure. The open network body is formed as an interconnected pore scaffold, such as a helix, truss arrangement, or random porous framework, and is configured to enable bone integration through the open porous scaffold. In some embodiments, the implant body includes a cannula extending entirely through the fixation implant from the head through the shank to the tip, with the open network positioned relative to threading and optional internal channels.

The implant further provides multiple structural embodiment variations for where the open network is present and how it coexists with other features. Embodiments include cannulated or non-cannulated forms, solid head and tip with open-porous regions along the threaded portion, and alternative distributions of porous versus solid portions. Variations also include fenestrated shank portions, non-porous solid material for the tip and head in one independent claim, and thread extents that can be continuous or include short unthreaded portions, with the open network body formed from metals and/or biocompatible polymers, including PEK, PEEK, PAEK, and combinations.

Claims Coverage

The document provides two independent claims, one directed to an implant that includes a cannula through the fixation implant and one directed to a fixation implant in which the tip and head are non-porous solid material. Each claim is centered on the combination of a head and tapered self-tapping tip with tool engagement and metal non-porous threadings, and an open network body comprising a scaffold of open and interconnected pores mimicking trabecular bone, with additional dimensional and structural constraints.

Across the independent claims, the coverage centers on a fixation implant that combines a head with a driving-tool recess, a tapered self-tapping tip, and metal non-porous first and second threadings, with an open network body with a scaffold of open and interconnected pores mimicking trabecular bone located in at least a portion of the shank. Both claims also impose outer-diameter constraints between head and shank with a consistent shank diameter profile, and require the first threading to be integral with a surface of the open network body; the cannula is required in the first independent claim, while non-porous solid material for the tip and head is required in the second independent claim.

Stated Advantages

Documented Applications