The methods disclosed herein of generating three-dimensional lattice structures and reducing stress shielding have applications including use in medical implants. One method of generating a three-dimensional lattice structure can be used to generate a structure lattice and/or a lattice scaffold to support bone or tissue growth. One method of reducing stress shielding includes generating a structural lattice to provide sole mechanical spacing across an area for desired bone or tissue growth. Some examples can use a repeating modified rhombic dodecahedron or radial dodeca-rhombus unit cell. Some methods are also capable of providing a lattice structure with anisotropic properties to better suit the lattice for its intended purpose.

A hip/shoulder prosthesis includes: a head component; a metaphyseal component; a diaphyseal nail, and a locking device. The head component includes: a front face and rear face; with a bore, and first and second shaped recesses in the rear face. The metaphyseal component includes: a central transverse aperture at an angle to the metaphyseal component's axis; a first end configured for threaded engagement within the bore of the head component; and a longitudinal hole that begins at the second end, transects the transverse aperture and reaches the first end, to receive the locking device. The diaphyseal nail is inserted in the femoral or humeral canal, and includes: fastening apertures that receive corresponding screws for fastening the diaphyseal nail to the femur or humerus; a portion configured to be received within, and engage, the transverse aperture of the metaphyseal component, and a transverse hole configured to receive the locking device.

Artificial intervertebral discs include an annulus fibrosus portion and a nucleus pulposus portion. Annulus fibrosus portions disclosed and contemplated herein include a plurality of layers. Fibers within the layers are arranged to provide a crisscross pattern between adjacent layers. Nucleus pulposus portions disclosed and contemplated herein can include a flexible, sealed enclosure.

A corpectomy cage includes a main body, a first end cap, and a second end cap. The main body is shaped as a hollow rectangular prism, and includes a first end and a second end. The first end has a plurality of first receivers formed therein, and the second end has a plurality of second receivers formed therein. The first end cap includes a plurality of first legs configured to be received within respective first receivers to removably engage the first end cap with the first end of the main body. Similarly, the second end cap includes a plurality of second legs configured to be received within respective second receivers to removably engage the second end cap with the second end of the main body. Each of the end caps further includes a plurality of teeth arranged opposite the plurality of legs.

The variable or adjustable depth medical implants in this application are capable of depth adjustment prior to implantation. The variable depth implants permit a single implant to provide multiple footprint configurations, allowing a surgeon footprint adjustability in the operating room. The implants can comprise a metallic lattice designed for specific physical properties, such as an elastic modulus. In some examples, the main body of the implant is taller than the adjustable portion of the implant (also referred to as the second implant body) so that the physical properties of the main body of the implant are controlling at the implant site. In some embodiments, the variable implant is constructed in an additive process as a single unit.

The methods disclosed herein of generating three-dimensional lattice structures and reducing stress shielding have applications including use in medical implants. One method of generating a three-dimensional lattice structure can be used to generate a structure lattice and/or a lattice scaffold to support bone or tissue growth. One method of reducing stress shielding includes generating a structural lattice to provide sole mechanical spacing across an area for desired bone or tissue growth. Some examples can use a repeating modified rhombic dodecahedron or radial dodeca-rhombus unit cell. Some methods are also capable of providing a lattice structure with anisotropic properties to better suit the lattice for its intended purpose.

Intervertebral spinal fusion implants for interbody fusion of the anterior column of the spine are described. The implants have a substantially bi-convex or a substantially offset bi-convex shape. The implants are placed through a transforaminal or posterior approach at an oblique insertion angle. The implants have an outermost point on the superior convex surface and an outermost point on the inferior convex surface and four edges of differing heights. The outermost superior and inferior points of the implants are connected with the four edges with convex surfaces of different curvatures. The curvatures of the convex surfaces of the implants are designed to match the curvatures of concave vertebral surfaces when the implants are inserted at an oblique insertion angle.

The biocompatible lattice structures and implants disclosed herein have an increased or optimized lucency, even when constructed from a metallic material. The lattice structures can also provide an increased or optimized lucency in a material that is not generally considered to be radiolucent. Lucency can include disparity, maximum variation in lucency properties across a structure, or dispersion, minimum variation in lucency properties across a structure. The implants and lattice structures disclosed herein may be optimized for disparity or dispersion in any desired direction. A desired direction with respect to lucency can include the anticipated x-ray viewing direction of an implant in the expected implantation orientation.

A prosthesis or implant device for use in joint or bone repair, or restoration of function. The prosthesis or implant device comprises a stem, in which a portion of the stem comprises non-overlapping lamellas around part or all of the circumference of the stem. Each lamella is connected to the external surface of the stem via a bending joint, which permits the space between the rest of the inner surface of the lamella and the external surface of the stem to decrease upon application of a force to the outer surface of the lamella. In addition, methods of treating a subject in need of joint replacement or bone repair using the prosthesis or implant device.

The biocompatible lattice structures and implants disclosed herein have an increased or optimized lucency, even when constructed from a metallic material. The lattice structures can also provide an increased or optimized lucency in a material that is not generally considered to be radiolucent. Lucency can include disparity, maximum variation in lucency properties across a structure, or dispersion, minimum variation in lucency properties across a structure. The implants and lattice structures disclosed herein may be optimized for disparity or dispersion in any desired direction. A desired direction with respect to lucency can include the anticipated x-ray viewing direction of an implant in the expected implantation orientation.