Joint support and subchondral support system

Abstract

A joint support and subchondral support system for providing structural and dampening support to damaged subchondral bone in generalized or discrete arthritis includes a contoured, porous plate having a variable shaped inner surface, outer surface, and peripheral surface of variable thickness extending between the inner surface and the outer surface, suitable for insertion within the subchondral bone. The inner surface, outer surface and peripheral surface each have a concave portion and a convex portion. A guide pin hole or slot is located within the contoured, porous plate to aid in insertion and placement of the plate over at least one corresponding guide pin within the subchondral bone. The joint support and subchondral support system of the present invention is applicable to many parts of the joint as any area with cartilage disease has an adjoining subchondral component.

Description

[0001]Cartilage disease has been previously addressed by various means of replacing or substituting the damaged cartilage. Microfracture or abrasionplasty is a form of irritating exposed bone to create replacement fibrocartilage, but the resultant material is inferior to native cartilage. Osteochondral transplant replaces plugs of diseased cartilage and accompanying subchondral bone with grafts from either the patient or human cadaver. Small discrete lesions work well, but larger lesions, bipolar disease, and diffuse disease are not well addressed. Chondrocyte implantation harvests the patient's cartilage cells, grows them, and re-implants them on the bony bed, and covers them with a periosteal patch. Each of the aforementioned techniques work best for small contained lesions, unipolar defects (i.e., one side of joint), and primarily femoral condyle lesions. Less optimal results occur with patellofemoral joint disease, and tibial sided disease.[0002]A further method of treating cart...

AI Technical Summary

Benefits of technology

[0010]It would be desirable to have a minimally invasive joint support and subchondral support system that specifically addresses the subchondral bone in arthritic disease process and progression, and relieves the pain that results from diseased subchondral bone and the spectrum of symptoms that result from arthritis, including pain, stiffness, swelling, and discomfort. It would be further desirable to have a joint support and subchondral support system that provides as follows: (1) a treatment specifically for bone edema and bone bruises and osteonecrosis that has previously not existed; (2) structural scaffolding to assist in the reparative processes of diseased bone next to joints; (3) shock absorbing enhancement to subchondral bone; (4) compressive, tensile, and especially shear stress attenuation enhancement to subchondral bone; (5) a means to prevent further joint deformity from subchondral bone remodeling such as osteophyte formation; (6) assistance in the healing of or prevention of further destruction of overlying cartilage by maintaining and allowing vascularity and nutritional support from subchondral bone; (7) assistance in the healing of or prevention of further destruction of overlying cartilage by providing an adequate structural base; (8) a minimally invasive alternative to total joint reconstruction that also does not preclude or further complicate joint reconstruction; (9) a treatment for subchondral bone disease in its role in arthritis and delay or halt further progression; (10) an implant for arthritis that is minimally subject to loosening or wear, as it is integral to the trabecular framework it supports; (11) an alternative for tibial sided, patellofemoral, and bipolar disease (tibial-femoral) that is relatively easy to perform, as an adjunct to arthroscopy, and as an outpatient procedure with minimal downtime for the patient; (12) a treatment for arthritis that allows higher lever of activity than that allowed after joint resurfacing or replacement; (13) a cost effective alternative to joint replacement with less issues about the need for revision and surgical morbidity, especially in countries with less medical resources; and (14) a treatment option in veterinary medicine, specifically in equine arthroses and arthritides.SUMMARY OF THE INVENTION

Problems solved by technology

Microfracture or abrasionplasty is a form of irritating exposed bone to create replacement fibrocartilage, but the resultant material is inferior to native cartilage.

Small discrete lesions work well, but larger lesions, bipolar disease, and diffuse disease are not well addressed.

Less optimal results occur with patellofemoral joint disease, and tibial sided disease.

Osteotomy also complicates latter joint replacement.

This type of procedure presents a prolonged recovery time and surgical risks.

Because total joint prostheses are fabricated of metal and plastic, revision surgery for worn-out components is fraught with much higher complications than primary surgery, and is inevitable if the patient lives much beyond ten years.

Namely, the inability of the bone to adequately repair itself as increasing damage occurs starts a cycle of further destruction, interfering with cartilage vascular supply and structural support.

Every joint has a physiologic envelope of function—when this envelope of function is exceeded, the rate of damage exceeds the rate of repair.

Clinical success of current cartilage surgery is limited as it generally only works for small, unipolar (one-sided joint) lesions of the femoral condyle.

No current treatment exists for bone edema or osteonecrosis of the knee.

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