Method and apparatus for accessing the interior of a hip joint, including the provision and use of a novel inflow access cannula

Abstract

An inflow access cannula system for allowing an instrument to access a remote surgical site, wherein the instrument comprises a distal portion having a smaller diameter and a proximal portion having a larger diameter, the system comprising: an inflow access cannula comprising a distal end, a proximal end and a central lumen extending therebetween, wherein the central lumen has a diameter larger than the distal portion of the instrument and smaller than the proximal portion of the instrument; and an instrument adapter for releasable connection to the inflow access cannula, the instrument adapter comprising a lumen communicating with the central lumen of the inflow access cannula, the lumen having a diameter larger than the proximal portion of the instrument, the instrument adapter further comprising a port and a fluid passageway connecting the port with the lumen of the instrument adapter, and a spacer for spacing the proximal portion of the instrument from the distal end of the inflow access cannula, such that when an instrument is disposed in the inflow access cannula system so that the distal portion of the instrument extends within the central lumen of the inflow access cannula and the proximal portion of the instrument is disposed in the central lumen of the instrument adapter and is in engagement with the spacer, fluid can flow into the port of the instrument adapter, along the fluid passageway of the instrument adapter, into the lumen of the instrument adapter and through the lumen of the inflow access cannula.

1 .- 15 . (canceled) 
     
     
         16 . Apparatus for accessing a remote surgical site with an instrument, the apparatus comprising:
 an access cannula comprising:
 a rigid elongated tube comprising a distal end, a proximal end and a lumen extending therebetween; and 
   an atraumatic tip mounted to the distal end of the elongated tube, wherein the atraumatic tip is overmolded around the tube so that the atraumatic tip extends radially outboard of the elongated tube and distally beyond the distal end of the elongated tube, and further wherein the atraumatic tip comprises barium sulfate in a range between 5 and 30% by weight.   
     
     
         17 . (canceled) 
     
     
         18 . A method for accessing a remote surgical site with an instrument, the method comprising:
 providing an access cannula comprising:
 a rigid elongated tube comprising a distal end, a proximal end and a lumen extending therebetween; and 
 an atraumatic tip mounted to the distal end of the elongated tube, wherein the atraumatic tip is overmolded around the tube so that the atraumatic tip extends radially outboard of the elongated tube and distally beyond the distal end of the elongated tube, and further wherein the atraumatic tip comprises barium sulfate in a range between 5 and 30% by weight; 
   advancing the access cannula through tissue to the surgical site; and   advancing the instrument into the lumen of the access cannula.   
     
     
         19 . A method for accessing a remote surgical site with an instrument, the method comprising:
 providing an access cannula comprising:
 a rigid elongated tube comprising a distal end, a proximal end and a lumen extending therebetween; and 
 an atraumatic tip mounted to the distal end of the elongated tube, wherein the atraumatic tip is overmolded around the tube so that the atraumatic tip extends radially outboard of the elongated tube and distally beyond the distal end of the elongated tube, and further wherein the atraumatic tip comprises barium sulfate in a range between 5 and 30% by weight; 
   providing an instrument adapter for releasable connection to the access cannula, the instrument adapter being adapted to mate with an instrument to be extended through the lumen of the access cannula;   advancing the access cannula through tissue to the surgical site;   mounting the instrument adapter to the instrument; and   advancing the instrument into the lumen of the access cannula so that the instrument adapter mounts to the access cannula.   
     
     
         20 .- 23 . (canceled) 
     
     
         24 . Apparatus according to  claim 16  wherein the elongated tube is formed out of at least one from the group consisting of a metal and a plastic. 
     
     
         25 . Apparatus according to  claim 16  wherein the atraumatic tip comprises a polymer. 
     
     
         26 . Apparatus according to  claim 16  wherein the atraumatic tip comprises a thermoplastic. 
     
     
         27 . Apparatus according to  claim 16  further comprising an obturator extending through the lumen of the elongated tube. 
     
     
         28 . Apparatus according to  claim 16  further comprising an instrument adapter for mounting an instrument to the access cannula, the instrument adapter being adapted to mate with an instrument to be extended through the lumen of the access cannula. 
     
     
         29 . Apparatus according to  claim 28  wherein the instrument adapter is releasably mounted to the access cannula by a bayonet mount. 
     
     
         30 . Apparatus according to  claim 29  wherein the bayonet mount comprises an L-shaped groove formed in the access cannula and a radial pin mounted to the instrument adapter. 
     
     
         31 . Apparatus according to  claim 30  wherein the instrument adapter comprises a body and a rotating collar rotatably mounted to the body, and wherein the radial pin is mounted to the rotating collar. 
     
     
         32 . Apparatus according to  claim 31  wherein the rotating collar is spring-biased relative to the body. 
     
     
         33 . Apparatus according to  claim 28  wherein the instrument comprises an endoscope. 
     
     
         34 . A system for accessing a remote surgical site with an instrument, the system comprising:
 an access cannula comprising:
 a rigid elongated tube comprising a distal end, a proximal end and a lumen extending therebetween; and 
   an atraumatic tip mounted to the distal end of the elongated tube, wherein the atraumatic tip is overmolded around the tube so that the atraumatic tip extends radially outboard of the elongated tube and distally beyond the distal end of the elongated tube, and further wherein the atraumatic tip comprises barium sulfate in a range between 5 and 30% by weight; and   an instrument adapter for releasable connection to the access cannula, the instrument adapter being adapted to mate with an instrument to be extended through the lumen of the access cannula.   
     
     
         35 . A system according to  claim 34  wherein the instrument comprises an endoscope. 
     
     
         36 . A system according to  claim 34  wherein the instrument comprises an obturator.