Joint replacement or joint resurfacing devices, systems and methods

Inventors

Khowaylo, Alex • Malayter, James • McCarthy, Michael P. • Washburn, David

Assignees

Penn State Research Foundation • Acuitive Technologies Inc

Abstract

Joint resurfacing and/or replacement devices, systems and methods that include thin film ternary ceramic coatings that are effective to provide reliable articulation and bearing surfaces and protection of both articular and modular junction surfaces from the potential for corrosion, wear, and fretting, and reduce the potential for release of metal ions from the joint systems. Isoelasticity is provided according to the particular joint resurfacing/replacement devices, systems and methods based on parameters that include material of construction, porosity and coating system. The thin film ternary ceramic coatings may be functionalized to enhance hydrophilicity and may be employed in any anatomical articulating joint region. Titanium alloy composite structures are provided that include an ultra-porous structured titanium alloy bone fixation surface and an opposed solid articular surface and a thin film ternary ceramic coating applied to one or both opposed surfaces.

Core Innovation

The invention relates to orthopedic joint replacement or joint resurfacing constructs that include a first element fabricated at least in part from a titanium alloy. The first element defines a porous or ultraporous fixation region and an engagement surface for articular movement relative to a second element, and exhibits a modulus that closely matches the modulus of host bone to which it is adapted to be mounted.

An engagement surface is provided with a thin film, non-porous ternary ceramic coating selected from TiAlN, TiCN, TiNbN, TiSiN, TiZrN, TiCrN, and combinations thereof. The thin film ternary ceramic coating is applied at a thickness of 20 microns or less to establish an inert barrier on the engagement surface, and the coated engagement surface and the second element engagement surface are configured and dimensioned for articular movement relative to each other.

In additional device configurations, one or more intermediate coating layers are applied to the engagement surface of the first element prior to the thin film ternary ceramic coating, with the ternary coating still at 20 microns or less. The coated surfaces function as inert barriers intended to reduce corrosion, fretting, wear, and metal-ion or particle release, while functionalization increasing hydrophilicity is described as supporting osteoblast activity and lubricity.

Claims Coverage

The document includes three independent claims that share a common core architecture: a titanium-alloy element with a porous or ultraporous fixation region and an engagement surface, an inert thin film non-porous ternary ceramic coating at 20 microns or less, and modulus matching to host bone. The independent claims differ in whether the orthopedic subject is a single device with a coated engagement surface, an orthopedic system including a second engagement surface in physical contact, or a device with additional intermediate coating layers.

Across the independent claims, the inventive coverage centers on combining a titanium-alloy element with porous or ultraporous fixation and bone-matching modulus, an engagement surface prepared with a non-porous thin film ternary ceramic inert barrier at 20 microns or less, and a coated configuration suited for articular movement relative to a second element. The orthopedic system claim additionally requires physical contact between first and second engagement surfaces, and the third independent claim allows one or more intermediate coating layers before the ternary ceramic coating.

Stated Advantages

Documented Applications