Prophylactic bactericidal implant

Abstract

A medical implant system is described for inhibiting infection associated with a joint prosthesis implant. An inventive system includes an implant body made of a biocompatible material which has a metal component disposed on an external surface of the implant body. A current is allowed to flow to the metal component, stimulating release of metal ions toxic to microbes, such as bacteria, protozoa, fungi, and viruses. One detailed system is completely surgically implantable in the patient such that no part of the system is external to the patient while the system is in use. In addition, externally controlled devices are provided which allow for modulation of implanted components.

1 . A medical implant system, comprising:
 an implant body made of a biocompatible material, the implant body having an external surface;   a metal component disposed on the external surface of the implant body;   a conduit for electrical current, the conduit in contact with the metal component; and   a power source in electrical communication with the conduit for electrical current.   
   
   
       2 . The medical implant system of  claim 1 , wherein the implant body further comprises:
 an internal cavity, the internal cavity having a wall and an opening; and   a cap removably disposed in the opening of the internal cavity, wherein the power source is disposed in the internal cavity and wherein the conduit is the implant body.   
   
   
       3 . The medical implant system of  claim 1 , wherein the implant body is adapted to be disposed totally within a human body when in use. 
   
   
       4 . The medical implant system of  claim 2 , further comprising a metal component disposed on a portion of the internal cavity wall. 
   
   
       5 . The medical implant system of  claim 1 , wherein the metal component comprises silver. 
   
   
       6 . The medical implant system of  claim 1 , wherein the metal component comprises a metal selected from the group consisting of: gold, zinc, copper, cadmium, cobalt, nickel, platinum, palladium, manganese, and chromium. 
   
   
       7 . The medical implant system of  claim 1 , wherein the metal component is a coating disposed on the external surface of the implant body. 
   
   
       8 . The medical implant system of  claim 7 , wherein the metal coating ranges in thickness between 1×10 −9 -5×10 −5  meters. 
   
   
       9 . The medical implant system of  claim 7 , wherein the metal coating is disposed on a portion of the external surface of the implant body ranging from 1-100% of the external surface of the implant body. 
   
   
       10 . The medical implant system of  claim 7  wherein the metal coating is disposed on a portion of the external surface of the implant body ranging from 50-99% of the external surface of the implant body. 
   
   
       11 . The medical implant system of  claim 7 , wherein the metal coating is disposed as a single region of continuous coating on the external surface. 
   
   
       12 . The medical implant system of  claim 7 , wherein the implant body comprises an articular surface having no coating. 
   
   
       13 . The medical implant system of  claim 7 , wherein the metal component is in the form of a wire disposed on the external surface. 
   
   
       14 . The medical implant system of  claim 1 , wherein the metal component is more electrically conductive than the biocompatible material. 
   
   
       15 . The medical implant system of  claim 1 , further comprising a resistor in electrical communication with the power source. 
   
   
       16 . The medical implant system of  claim 1 , further comprising a switch in electrical communication with the power source. 
   
   
       17 . The medical implant system of  claim 16 , further comprising a controller in signal communication with the switch. 
   
   
       18 . The medical implant system of  claim 2 , wherein the cap is made of an electrically insulating material. 
   
   
       19 . The medical implant system of  claim 1 , further comprising an electrically insulating material disposed between the external surface of the implant body and the metal component. 
   
   
       20 . The medical implant system of  claim 17 , wherein the controller is external to the body of an individual having an implant body disposed therein. 
   
   
       21 . A method for inhibiting microbial infection associated with an orthopedic implant, comprising:
 providing a medical implant system according to  claim 1 ;   delivering a current to a metal component disposed on an external surface of an implant body, the implant body located in a human body at a site of potential infection, wherein the delivery of current to the metal component causes release of metal ions toxic to an infectious microbe at the site of potential infection, such that microbial infection is inhibited.