An optimized press-fit between a resected bone and an articular implant may, for instance, reduce undesirable qualities, including excess micromotion, stress transmission, and/or strain. By taking into account heterogeneous bone properties, the parameters of a bone resection can be determined as to optimize the press-fit between a resected bone and an articular implant. An optimized press-fit is obtained by determining ideal engagement characteristics corresponding to the fit between the fixation features of an articular implant and a bone. Then, taking into account a bone's heterogeneous properties, the parameters of a bone resection that would substantially achieve the determined ideal engagement characteristics are determined.

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 device used in conjunction with fixation hardware to provide a two-stage process to address the competing needs of immobilization and re-establishment of normal stress-strain trajectories in grafted bone. A method of determining a patient-specific stress/strain pattern that utilizes a model based on 3D CT data of the relevant structures and cross-sectional data of the three major chewing muscles. The forces on each of the chewing muscles are determined based on the model using predetermined bite forces such that a stiffness of cortical bone in the patient's mandible is determined. Based on the stiffness data, suitable implantation hardware can be designed for the patient by adjusting external topological and internal porous geometries that reduce the stiffness of biocompatible metals to thereby restore normal bite forces of the patient.

The present disclosure in one aspect provides a surgical implant comprising an upper bone contacting surface comprising a plurality of irregularly shaped pores having an average pore size, where the pores are formed by a plurality of struts, a lower bone contacting surface comprising a plurality of irregularly shaped pores having an average pore size, wherein the pores are formed by a plurality of struts; and a central body comprising a plurality of irregularly shaped pores having an average pore size, wherein the pores are formed by a plurality of struts, wherein the average pore size on the upper and lower bone contacting surfaces is different than the average pore size on the central body.

A spinal implant for insertion into and positioning in an intervertebral space is provided. The insert comprises a compressible support configured to change the height of the insert, wherein the insert comprises a first portion having a first surface and a compressible support adjacent to the first surface; and a second portion having a second surface and a second compressible support adjacent to the second surface. A method for fusing two adjacent vertebrae utilizing the spinal implant including the bone insert is also provided.

A device adapted to be positioned between two bone regions, the device comprising at least one wall defining at least one interior cavity, and, a load arrangement extending from the wall and comprising at least one interacting feature configured to load material positioned within the cavity by interacting with either a second interacting feature or the wall.

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.

The embodiments provide various interbody fusion spacers, or cages, for insertion between adjacent vertebrae. These intervertebral cages can restore and maintain intervertebral height of the spinal segment to be treated, and stabilize the spine by restoring sagittal balance and alignment. The cages may have a first, insertion configuration characterized by a reduced size at each of their insertion ends to facilitate insertion through a narrow access passage and into the intervertebral space. The cages may be expanded to a second, expanded size once implanted. In their second configuration, the cages are able to maintain the proper disc height and stabilize the spine by restoring sagittal balance and alignment. The intervertebral cages are configured to be able to adjust the angle of lordosis, and can accommodate larger lodortic angles in their second, expanded configuration. Further, these cages may promote fusion to further enhance spine stability by immobilizing the adjacent vertebral bodies.

In one embodiment, a prosthetic component includes a plurality of fixation pads coupled to a body portion. The fixation pads may be formed of a first material suitable for attachment to bone, and the body portion may be formed of a second material different from the first material and suitable to provide a bearing surface for a joint.

The present invention relates generally to a prosthetic spinal disc for replacing a damaged disc between two vertebrae of a spine and methods for inserting said discs. The intervertebral prosthetic discs are provided with connections for facilitating implantation and removal and features which enhance primary and secondary stability over time.