A system and method for improving mechanical assemblies, such as prosthetic implants, intended to be installed in living tissue such as bone. Force-imparting devices are adapted and may include angularity, which may be introduced with specialized additive manufacturing, which may impart congruent cross-sections while providing variable stiffness. In some cases, the variable stiffness may be stretchy in a longitudinal direction and rigid in a radial directional which may provide an assembly bias. Additive manufacturing may allow the material of a prosthesis to be varied (e.g., density/porosity) to create variable stiffness over a length.

An interbody implant system for use in the spine includes a base comprising two or more bone contacting surfaces, at least one recess in at least one of the two or more bone contacting surfaces, the recess configured for containing a tooth, a deployable tooth to provide fixation between the base and the anatomy of a subject, a break-away bridge between the tooth and the base for providing a first relative position between the tooth and the base, and a locking mechanism for providing a second relative position between the tooth and the base.

In some aspects, the present invention is a medical implant with an independent endplate structure that can stimulate bone or tissue growth in or around the implant. When used as a scaffold for bone growth, the inventive structure can increase the strength of new bone growth. The independent endplate structures generally include implants with endplates positioned on opposite sides of the implant and capable of at least some movement relative to one another. In most examples, the endplates have a higher elastic modulus than that of the bulk of the implant to allow the use of an implant with a low elastic modulus, without risk of damage from the patient's bone. A method of designing independent endplate implants is also disclosed, including ranges of elastic moduli for the endplates and bulk of the implant for given implant parameters. Implants with elastic moduli within the ranges disclosed herein can optimize the loading of new bone growth to provide increased bone strength.

The biocompatible lattice structures disclosed herein with an increased or optimized lucency are prepared according to multiple methods of design disclosed herein. The methods allow for the design of a metallic material with sufficient strength for use in an implant and that remains radiolucent for x-ray imaging.

The three-dimensional lattice structures disclosed herein have applications including use in medical implants. Some examples of the lattice structure are structural in that they can be used to provide structural support or mechanical spacing. In some examples, the lattice can be configured as a scaffold to support bone or tissue growth. Some examples can use a repeating modified rhombic dodecahedron or radial dodeca-rhombus unit cell. The lattice structures are also capable of providing a lattice structure with anisotropic properties to better suit the lattice for its intended purpose.

A placeholder for vertebrae or vertebral discs includes a tubular body, which along its jacket surface has a plurality of breakthroughs or openings for over-growth with adjacent tissue. The placeholder includes at least a second tubular body provided with a plurality of breakthroughs and openings at least partially inside the first tubular body. The first and second tubular bodies can have different cross-sectional shapes, can be are arranged inside one another by press fit or force fit or can be connected to each other via connecting pins and arranged side by side to one another in the first body.

Disclosed herein are systems and methods for intervertebral body fusion that provide more robust support within the disc space. Intervertebral body fusion devices can have a unitary monolithic body including a plurality of body segments interconnected with each other by flexure members. Devices be configured to be inserted through an opening in a compressed configuration and then expanded within the disc space to an expanded configuration. In the expanded configuration, devices can have a greater mediolateral or transverse to the disc space footprint. This wider footprint provides greater support for the vertebrae relative to the size of the opening through which the device is inserted.

A placeholder for vertebrae or vertebral discs includes a tubular body, which along its jacket surface has a plurality of breakthroughs or openings for over-growth with adjacent tissue. The placeholder includes at least a second tubular body provided with a plurality of breakthroughs and openings at least partially inside the first tubular body. The first and second tubular bodies can have different cross-sectional shapes, can be are arranged inside one another by press fit or force fit or can be connected to each other via connecting pins and arranged side by side to one another in the first body.

A system and method for improving mechanical assemblies, such as prosthetic implants, intended to be installed in living tissue such as bone. Force-imparting devices are adapted and may include angularity, which may be introduced with specialized additive manufacturing, which may impart congruent cross-sections while providing variable stiffness. In some cases, the variable stiffness may be stretchy in a longitudinal direction and rigid in a radial directional which may provide an assembly bias. Additive manufacturing may allow the material of a prosthesis to be varied (e.g., density/porosity) to create variable stiffness over a length.

A system and method for improving mechanical assemblies, such as prosthetic implants, intended to be installed in living tissue such as bone. Force-imparting devices are adapted and may include angularity, which may be introduced with specialized additive manufacturing, which may impart congruent cross-sections while providing variable stiffness. In some cases, the variable stiffness may be stretchy in a longitudinal direction and rigid in a radial directional which may provide an assembly bias. Additive manufacturing may allow the material of a prosthesis to be varied (e.g., density/porosity) to create variable stiffness over a length.