US 11,992,409 B2 · Implant for bone segment fusion

Abstract

A bone screw implant is provided for immobilizing the articular surfaces of two bone segments by securing, fusing, or compression the two segments. The implant may be fabricated from a porous biocompatible metal and have a cylindrical shape and fully or partially threaded and may have variable pitch threads and a variable diameter of the shaft. The implant may include a blunt tip or a fluted self-drilling tip and a headless screwdriver socket. Large pitch cancellous threads may be in the leading-end portion of the cylinder shaft, and smaller pitch cortical threads may be at the trailing edge portion of the shaft. The implant may be fenestrated, it may have a roughened surface, and it may be coated with an osteoconductive material. The implant may be cannulated. In a specific embodiment, the implant is used for immobilizing the articular surfaces of a sacroiliac joint. The implant may be coated with hydroxyapatite or tricalcium phosphate at thickness of 100 nm to 100 μm thick.

Claims20

Dependent claims

An implant for bone fusion or fixation, comprising:

a. A cylindrical threaded implant fabricated from a titanium or tantalum metal or alloy with a similar modulus of elasticity to the bone, wherein the titanium or tantalum metal or alloy is a porous material with pore sizes ranging in 100 to 900 μm and a porosity of 60-65%;
b. wherein the cylinder comprises a shaft, wherein the shaft (120) of the cylinder of the implant has a diameter between 4 mm to 14 mm and length between 10 mm to 280 mm;
c. wherein the implant has a distal section (122) with a distal end (125);
d. wherein the implant has a headless proximal section (123) and a proximal end (150) having a socket (152) for attachment to a tool that can rotate to screw the implant into place;
e. wherein the implant is threaded with large pitch cancellous helical threads (142) on a portion of the shaft (120), or smaller pitch cortical helical threads (144) on a portion of shaft (123), or wherein the implant has uniform threads (FIG. 12, 142);
f. wherein the implant has at least one fenestration (160) penetrating through the body of the implant latitudinally;
g. wherein the implant is surface treated to have a roughened surface;
and
h. wherein the implant is coated with hydroxyapatite (HA) or tricalcium phosphate (TCP) or both wherein the coating is 100 nm to 100 μm thick.

6 more elements

A fusion or fixation implant for immobilizing the articular surfaces of a joint or segment of bone or fracture comprising:

a. A cylindrical threaded implant fabricated from a titanium or tantalum metal or alloy with a similar modulus of elasticity to the bone, wherein the titanium or tantalum metal or alloy is a porous material with pore sizes ranging in 100 to 900 μm and a porosity of 60-65%;
b. wherein the cylinder comprises a shaft, wherein the shaft of the cylinder of the implant has a diameter between 4 mm to 14 mm and length between 10 mm to 280 mm;
c. wherein the implant has a distal section with a fluted distal end (125);
d. wherein the implant has a flared headless proximal section (123) and a proximal end (152) having a socket (152) for attachment to a tool that can rotate to screw the implant into place;
e. wherein the implant is fully threaded with large pitch cancellous helical threads (142) on the shaft on a portion of the distal section, and smaller pitch cortical helical threads (144) on the shaft on a portion of the proximal section;
f. wherein the implant has a central channel (134) longitudinally spanning the entire length;
g. wherein a set of secondary female threads (170) is in the central channel adjacent to the socket in the proximal end;
h. wherein the implant has one or more fenestrations (160);
i. wherein the implant is surface treated to have a roughened surface;
and
j. wherein the implant is coated with hydroxyapatite (HA) or tricalcium phosphate (TCP) or both wherein the coating is 100 nm to 100 μm thick.

8 more elements

Dependencies are inferred from the claim text.

Implant for bone segment fusion

Life of this patent

Implant for bone segment fusion

Life of this patent

Abstract

Claims20