Antibiotic delivery system and method for treating an infected synovial joint during re-implantation of an orthopedic prosthesis

Abstract

An antibiotic delivery system including an intramedullary stem that is adapted to be removably mounted into a medullary canal of a bone. The stem includes a body having an inlet adapted to be in fluid communication with a source of liquid-borne antibiotic and a plurality of outlets disposed along the stem. A channel extends between the inlet and the plurality of outlets for delivering a fluid-borne antibiotic from the inlet to the plurality of outlets so as to distribute the antibiotic along the medullary canal in a controlled fashion. A method of treating an infected joint during a two-stage re-implantation of an orthopedic implant is also disclosed.

What is claimed is: 
     
       1. An antibiotic delivery system comprising:
 a femoral intramedullary stem adapted to be removably mounted into a medullary canal of a femur bone, said femoral intramedullary stem including a body having a proximate end and a distal end disposed remote from said proximate end, said body including a plurality of fins extending therealong and disposed in spaced angular relationship with respect to each other so as to define valleys that provide fluid flow spaces disposed between adjacent fins, said fins adapted to engage said medullary canal in a removably stable fashion, a femoral head and a neck extending from said proximal end of said body and between said body and said femoral head, said femoral intramedullary stem including at least one inlet, and a plurality of outlets disposed along said stem and between an outer surface of one of said plurality of adjacent fins in said valleys and in fluid communication with said fluid flow spaces and a channel extending between said inlet and said plurality of outlets, said femoral head having a plurality of outlets and a channel extending between said at least one inlet and said plurality of outlets for delivering fluid-borne antibiotics from said at least one inlet to said plurality of outlets so as to distribute said antibiotic along said intramedullary canal and the socket of a hip joint in a controlled fashion.   
     
     
       2. An antibiotic delivery system as set forth in  claim 1 , wherein said body includes an inlet and said femoral head includes an inlet, both inlets being in fluid communication with a source of fluid-borne antibiotic. 
     
     
       3. An antibiotic delivery system as set forth in  claim 1 , wherein said femoral head has a hemispherical shape so as to be complimentarily received in the socket of a hip joint. 
     
     
       4. A method of treating an infected joint during a two-stage re-implantation of an orthopedic implant, said method comprising the steps of: removing the infected implants mounted to the medullary canal of a bone; debriding the medullary canal; installing an intramedullary stem into the medullary canal where the stem includes an inlet, a plurality of outlets and a channel extending between the inlet and the plurality of outlets; said stem including a plurality of fins extending along a longitudinal axis of the stem and disposed in spaced angular relationship with respect to each other so as to define valleys that provide fluid flow spaces disposed between adjacent fins and a plurality of outlets disposed along said stem and between an outer surface of one of said plurality of adjacent fins in said valleys and in fluid communication with said fluid flow spaces providing a source of fluid-borne antibiotic to the inlet of the intramedullary stem so as to distribute the antibiotic into the medullary canal in a controlled fashion. 
     
     
       5. A method of treating an infected orthopedic implant as set forth in  claim 4 , wherein said step of installing an intramedullary stem includes installing a tibial intramedullary stem into the medullary canal of the tibia bone and installing a femoral intramedullary stem into the medullary canal of a femur bone. 
     
     
       6. A method of treating an infected orthopedic implant as set forth in  claim 5 , wherein the method further includes the step of positioning a coupler between the tibial intramedullary stem and the femoral intramedullary stem so as to provide axial stability between the tibial and femoral intramedullary stems. 
     
     
       7. A method of treating an infected orthopedic implant as set forth in  claim 6 , wherein the method further includes the step of establishing fluid communication between the coupler and the inlet of the tibial and femoral intramedullary stems and providing fluid communication between the coupler and a source of fluid-borne antibiotic so as to distribute the antibiotic through the tibial and femoral intramedullary stems and along the medullary canals in a controlled fashion. 
     
     
       8. A system for treating infected tissue, the system comprising:
 a source of a fluid;   an intramedullary stem adapted to be removably mounted into a medullary canal of a bone;   wherein the medullary canal of the bone is defined by an inner wall of the bone,   wherein the intramedullary stem comprises a body with a longitudinal axis, a proximal end, a distal end, an outer body surface adapted to engage the inner wall of the bone, an inlet in fluid communication with the source of the fluid, a plurality of outlets disposed longitudinally along the outer body surface, and a channel extending between the inlet and the plurality of outlets, the body including a plurality of fins extending therealong and disposed so as to define valleys that provide fluid flow spaces disposed between adjacent fins, wherein the fluid is delivered from the source to the plurality of outlets so as to distribute the fluid along the medullary canal in a controlled fashion; and   a negative pressure wound therapy system for treating the infected tissue.   
     
     
       9. The system of claim 8, wherein the fluid comprises one or more of an antibiotic, antimicrobial, antibacterial, irrigation fluid and cleansing fluid. 
     
     
       10. The system of claim 9, wherein the fluid comprises two antibiotics. 
     
     
       11. The system of claim 10, wherein the two antibiotics comprise Tobramycin and Vancomycin. 
     
     
       12. The system of claim 8, wherein the plurality of outlets are disposed at least partially circumferentially along the outer body surface. 
     
     
       13. The system of claim 8, wherein the plurality of fins extend along the longitudinal axis of the body and wherein the plurality of fins are spaced at least partially circumferentially along the outer body surface so as to define one or more valleys between adjacent fins,
 wherein the plurality of fins comprise an outer surface adapted to engage the inner wall of the bone.   
     
     
       14. The system of claim 13, wherein the plurality of fins are spaced evenly circumferentially along the outer body surface. 
     
     
       15. The system of claim 13, wherein the outer surface of the plurality of fins is irregularly contoured so as to form fluid flow spaces therealong and to permit the fluid to flow past the fluid flow spaces. 
     
     
       16. The system of claim 15, wherein the irregularly contoured outer surface of the plurality of fins comprises serrations. 
     
     
       17. The system of claim 8, wherein the intramedullary stem further comprises a base plate at the proximal end thereof. 
     
     
       18. The system of claim 17, wherein the inlet is disposed on the base plate. 
     
     
       19. The system of claim 8, wherein the intramedullary stem body tapers along the longitudinal axis from the proximal end to the distal end. 
     
     
       20. The system of claim 8, further comprising a pump, wherein the pump is either:
 in fluid communication with the source of the fluid and the inlet of the intramedullary stem, wherein the pump acts to control delivery of the fluid to the medullary canal through the plurality of outlets of the intramedullary stem; or   the pump applies a vacuum for the negative pressure wound therapy system.   
     
     
       21. The system of claim 20, wherein the pump pumps the fluid in a pulsatile fashion. 
     
     
       22. The system of claim 20, wherein the pump:
 is in fluid communication with the source of the fluid and the inlet of the intramedullary stem, wherein the pump acts to control delivery of the fluid to the medullary canal through the plurality of outlets of the intramedullary stem; and   the pump applies a vacuum for the negative pressure wound therapy system.   
     
     
       23. The system of claim 8, wherein the bone comprises a femur bone or a tibia bone and the medullary canal extends therethrough, and wherein the intramedullary stem is adapted to be removably mounted in the medullary canal. 
     
     
       24. The system of claim 8, further comprising:
 a second intramedullary stem adapted to be removably mounted into a second medullary canal of a second bone, wherein the second medullary canal of the second bone is defined by a second inner wall of the second bone,   wherein the second intramedullary stem comprises a second body with a second longitudinal axis, a second proximal end, a second distal end, a second outer body surface that is adapted to engage the second inner wall of the second bone, a second inlet in fluid communication with the source of the fluid, a plurality of second outlets disposed longitudinally along the second outer body surface, and a second channel extending between the second inlet and the plurality of second outlets, wherein the fluid is delivered from the source to the plurality of second outlets so as to distribute the fluid along the second medullary canal in a controlled fashion; and   a coupler, wherein the coupler joins the intramedullary stem with the second intramedullary stem.   
     
     
       25. The system of claim 24, wherein the coupler stabilizes a joint defined between the intramedullary stem and the second intramedullary stem. 
     
     
       26. The system of claim 24, wherein the coupler comprises an inlet in fluid communication with the fluid, and wherein the coupler further comprises at least one outlet in fluid communication with the inlet of the intramedullary stem and the inlet of the second intramedullary stem, whereby the coupler distributes the fluid from the source to the plurality of outlets of the intramedullary stem and the plurality of second outlets of the second intramedullary stem. 
     
     
       27. The system of claim 8, wherein the intramedullary stem further comprises a neck and a head, wherein the neck is disposed at the proximal end of the intramedullary stem, and wherein the head is coupled to the neck,
 wherein the head comprises an outer head surface that is configured to engage a socket of a joint, a plurality of outlets disposed along the outer head surface and in fluid communication with the inlet of the intramedullary stem, and   wherein the fluid is further delivered from the source to the plurality of outlets disposed along the outer head surface so as to distribute the fluid along the socket of the joint in a controlled fashion.   
     
     
       28. An intramedullary implant for treating infected tissue, said intramedullary implant comprising:
 a stem adapted to be removably mounted into a medullary canal of a bone, the medullary canal defined by an inner wall of the bone, wherein the stem comprises a longitudinal axis, a proximal end, a distal end, an outer stem surface adapted to engage the inner wall of the bone, an inlet in fluid communication with a fluid, a plurality of outlets disposed longitudinally along the outer stem surface, and a channel extending between the inlet and the plurality of outlets, the stem including a plurality of fins extending therealong and disposed so as to define valleys that provide fluid flow spaces disposed between adjacent fins, wherein the fluid is adapted to be delivered from the plurality of outlets to the medullary canal in a controlled fashion.   
     
     
       29. The implant of claim 28, wherein the plurality of outlets are disposed at least partially circumferentially along the outer stem surface. 
     
     
       30. The implant of claim 28, wherein the plurality of fins extend along the longitudinal axis of the stem and wherein the plurality of fins are spaced at least partially circumferentially along the outer stem surface so as to define one or more valleys between adjacent fins,
 wherein the plurality of fins comprise an outer surface adapted to engage the inner wall of the bone.   
     
     
       31. The implant of claim 29, wherein the plurality of fins are spaced evenly circumferentially along the outer stem surface. 
     
     
       32. The implant of claim 29, wherein the outer surface of the plurality of fins is irregularly contoured so as to form fluid flow spaces therealong and to permit the fluid to flow past the fluid flow spaces. 
     
     
       33. The implant of claim 32, wherein the irregularly contoured outer surface of the plurality of fins comprises serrations. 
     
     
       34. The implant of claim 28, wherein the stem further comprises a base plate at the proximal end thereof. 
     
     
       35. The implant of claim 34, wherein the inlet is disposed on the base plate. 
     
     
       36. The implant of claim 28, wherein the stem tapers along the longitudinal axis from the proximal end to the distal end. 
     
     
       37. The implant of claim 28, wherein the bone comprises a femur bone or a tibia bone and the medullary canal extends therethrough, and wherein the stem is adapted to be removably mounted in the medullary canal. 
     
     
       38. An intramedullary implant for treating infected tissue, said intramedullary implant comprising:
 a stem adapted to be removably mounted into a medullary canal of a bone, the medullary canal defined by an inner wall of the bone, wherein the stem comprises a longitudinal axis, a proximal end, a distal end, an outer stem surface adapted to engage the inner wall of the bone, at least one inlet in fluid communication with a fluid, a plurality of outlets disposed longitudinally along the outer stem surface, and a channel extending between the at least one inlet and the plurality of outlets, the stem including a plurality of fins extending therealong and disposed so as to define valleys that provide fluid flow spaces disposed between adjacent fins;   a neck disposed at the proximal end of the stem; and   a head coupled to the neck, wherein the head comprises an outer head surface that is configured to engage a socket of a joint, a plurality of outlets disposed along the outer head surface and in fluid communication with the at least one inlet; and   wherein the fluid is adapted to be delivered from the plurality of outlets of the stem to the medullary canal in a controlled fashion, and   wherein the fluid is adapted to be delivered from the plurality of outlets of the head to the socket of the joint in a controlled fashion.   
     
     
       39. The implant of claim 38, wherein the head comprises an inlet, the inlet being in fluid communication with the plurality of outlets of the outer head surface. 
     
     
       40. The implant of claim 38, wherein the plurality of fins extend along the longitudinal axis of the stem and wherein the plurality of fins are spaced at least partially circumferentially along the outer stem surface so as to define one or more valleys between adjacent fins,
 wherein the plurality of fins comprise an outer surface adapted to engage the inner wall of the bone.   
     
     
       41. The implant of claim 40, wherein the plurality of fins are spaced evenly circumferentially along the outer stem surface. 
     
     
       42. The implant of claim 40, wherein the outer surface of the plurality of fins is irregularly contoured so as to form fluid flow spaces therealong and to permit the fluid to flow past the fluid flow spaces. 
     
     
       43. The implant of claim 42, wherein the irregularly contoured outer surface of the plurality of fins comprises serrations. 
     
     
       44. The implant of claim 38, wherein the stem tapers along the longitudinal axis from the proximal end to the distal end. 
     
     
       45. The implant of claim 38, wherein the bone comprises a femur bone and the medullary canal extends therethrough, wherein the intramedullary stem is adapted to be removably mounted in the medullary canal, and wherein the head is adapted to be engaged in a socket of a hip joint. 
     
     
       46. The system of claim 8, wherein the plurality of fins extend along the body from the proximal end to the distal end, and wherein the plurality of fins extend substantially along an entire length of the body. 
     
     
       47. The system of claim 8, wherein a depth of the plurality of fins is configured to anchor the plurality of fins within the intramedullary canal while providing the defined valleys that provide fluid flow spaces disposed between adjacent fins. 
     
     
       48. The implant of claim 28, wherein the plurality of fins extend along the body from the proximal end to the distal end, and wherein the plurality of fins extend substantially along an entire length of the body. 
     
     
       49. The implant of claim 28, wherein a depth of the plurality of fins is configured to anchor the plurality of fins within the intramedullary canal while providing the defined valleys that provide fluid flow spaces disposed between adjacent fins. 
     
     
       50. The implant of claim 38, wherein the plurality of fins extend along the body from the proximal end to the distal end, and wherein the plurality of fins extend substantially along an entire length of the body. 
     
     
       51. The implant of claim 38, wherein a depth of the plurality of fins is configured to anchor the plurality of fins within the intramedullary canal while providing the defined valleys that provide fluid flow spaces disposed between adjacent fins.