Adjustable spacer

Abstract

A medical targeting and device introduction system includes an introducer having a cannula, and a hub. The cannula is defined, at least in part, by an inner lumen. The hub includes a latch to releasably secure the hub to a biopsy device. The hub includes a proximal end and a distal end. The latch extends from the proximal end, and the hemostatic valve is interposed within the introducer.

1 . (canceled) 
     
     
         2 . An introducer assembly for transcutaneously placing an elongate medical device in a patient, the assembly comprising:
 an introducer including an introducer cannula having a proximal end and a distal end; and   an axial distance adjustment system for providing an adjustable distance between a proximal end of the axial distance adjustment system and the distal end of the introducer cannula, the axial distance adjustment system comprising a first hub having a first interference surface, and a second hub having second and third interference surfaces,   wherein a distal end of the axial distance adjustment system is releasably coupled to the proximal end of the introducer, and   wherein the first hub and the second hub are selectively restrained from axial movement with respect to each other when the first interference surface contacts one of the second interference surface and the third interference surface.   
     
     
         3 . The assembly of  claim 2 , wherein at least one of the first hub and the second hub includes an axially extending surface portion and at least a portion of the first interference surface is selectively movable along the axially extending surface portion to thereby adjust the distance between the proximal end of the axial distance adjustment system and the distal end of the introducer cannula. 
     
     
         4 . The assembly of  claim 3 , wherein the second interference surface and the third interference surface each projects perpendicularly from the axially extending surface portion. 
     
     
         5 . The assembly of  claim 2 , further comprising a plurality of indications to indicate a relative axial position of the first hub with respect to the second hub. 
     
     
         6 . The assembly of  claim 5 , wherein at least a portion of the plurality of indications indicates a length of the axial distance adjustment system. 
     
     
         7 . The assembly of  claim 2 , wherein one of the first and second hubs comprises a flange and the other of the first and second hubs comprises a projection that cooperates with the flange to limit shortening of the distance between the proximal end of the axial distance adjustment system and the distal end of the introducer cannula. 
     
     
         8 . The assembly of  claim 2 , the axial distance adjustment system further comprising a handle disposed at the proximal end thereof. 
     
     
         9 . The assembly of  claim 2 , wherein the axial distance adjustment system includes a latch portion at a distal end thereof that releasably couples the distal end of the axial distance adjustment system to the proximal end of the introducer. 
     
     
         10 . The assembly of  claim 2 , wherein the first and second hubs are disposed coaxially. 
     
     
         11 . The assembly of  claim 10 , wherein the introducer cannula and one of the first and second hubs define a continuous lumen. 
     
     
         12 . The assembly of  claim 11 , further comprising an elongate medical device slidably disposed in the lumen. 
     
     
         13 . The assembly of  claim 12 , wherein the proximal end of axial distance adjustment system comprises a flange configured to cooperate with a projection disposed on the medical device to limit distal insertion of the medical device through the lumen. 
     
     
         14 . The assembly of  claim 12 , wherein the elongate medical device is selected from the group consisting of a biopsy needle, a push rod, a stylet, and an obturator. 
     
     
         15 . The assembly of  claim 2 , wherein each of the first and second hubs has a cylindrical outer surface. 
     
     
         16 . The assembly of  claim 2 , wherein the first interference surface is disposed on an orthogonal projection from a surface of the first hub. 
     
     
         17 . The assembly of  claim 16 , wherein each of the second and third interference surfaces is disposed on a circumferential locking slot formed on a surface of the second hub. 
     
     
         18 . The assembly of  claim 17 , wherein the second hub further comprises an axial guide slot formed in the surface of the second hub, wherein the axial guide slot is parallel to a longitudinal axis of the second hub. 
     
     
         19 . The assembly of  claim 18 , wherein each of the second and third interference surfaces projects perpendicularly from the axial guide slot. 
     
     
         20 . An introducer assembly for transcutaneously placing an elongate medical device in a patient, the assembly comprising:
 an introducer including an introducer cannula having a proximal end and a distal end; and   an axial distance adjustment system for providing an adjustable distance between a proximal end of the axial distance adjustment system and the distal end of the introducer cannula, the axial distance adjustment system comprising a first hub having a first interference surface, and a second hub having second and third interference surfaces,   wherein the first and second hubs are disposed coaxially,   wherein a distal end of the axial distance adjustment system is releasably coupled to the proximal end of the introducer, such that the introducer cannula and one of the first and second hubs define a continuous lumen, and   wherein at least one of the first hub and the second hub includes an axially extending surface portion and at least a portion of the first interference surface is selectively movable along the axially extending surface portion to thereby adjust the distance between the proximal end of the axial distance adjustment system and the distal end of the introducer cannula.