Abstract:
The present invention provides a minimally-invasive portal system for performing lumbar decompression, instrumented fusion/stabilization, and the like. The minimally-invasive portal system utilizes an access tube having an adjustable cross-sectional area and one or more retractor devices each having a first portion and a second portion aligned at a predetermined angle relative to the first portion, wherein the first portion of each of the one or more retractor devices is disposed substantially concentrically with the access tube, and wherein the second portion of each of the one or more retractor devices protrudes substantially beyond a bottom portion of the access tube. The minimally-invasive portal system also utilizes a plurality of adjustment mechanisms for selectively adjusting the cross-sectional area of the access tube and one or more retaining clips for securing the one or more retractor devices to the access tube in a fixed position.

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     The present non-provisional patent application claims the benefit of priority of U.S. Provisional Patent Application No. 60/639,936, filed Dec. 29, 2004, and entitled “MINIMALLY-INVASIVE PORTAL SYSTEM FOR PERFORMING LUMBAR DECOMPRESSION, INSTRUMENTED FUSION/STABILIZATION, AND THE LIKE,” which is incorporated in-full by reference herein. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to the medical and surgical fields. More specifically, the present invention relates to a minimally-invasive portal system for performing lumbar decompression, instrumented fusion/stabilization, and the like. Advantageously, the minimally-invasive portal system of the present invention provides enhanced access to and visualization of an area of interest within the body of a human patient, a veterinary patient, or the like, such that a surgical procedure may be performed, especially a surgical procedure involving the lumbar or cervical spine of the patient. 
     BACKGROUND OF THE INVENTION 
     Various portal systems exist in the prior art for providing access to and visualization of an area of interest within the body of a human patient, a veterinary patient, or the like, such that a surgical procedure may be performed, especially a surgical procedure involving the lumbar or cervical spine of the patient. However, none of these portal systems are capable of being inserted and/or adjusted such that they are sufficiently minimally invasive. Advantageously, minimally-invasive medical and surgical systems and procedures result in as little damage and trauma to adjacent anatomical structures as possible, thus minimizing discomfort and speeding recovery. For example, it is important in surgical procedures involving the lumbar or cervical spine of a patient to minimize damage and trauma to the skin, musculature, and ligaments adjacent to the spine. Of primary importance, however, is providing an adequate field of view. 
     Thus, what is needed is an improved minimally-invasive portal system that provides enhanced access to and visualization of an area of interest within the body of a human patient, a veterinary patient, or the like, such that a surgical procedure may be performed, especially a surgical procedure involving the lumbar or cervical spine of the patient. The minimally-invasive portal system should be relatively simple to insert, adjust, and remove, and should provide an adequate field of view. 
     BRIEF SUMMARY OF THE INVENTION 
     In various exemplary embodiments, the present invention provides a minimally-invasive portal system that provides enhanced access to and visualization of an area of interest within the body of a human patient, a veterinary patient, or the like, such that a surgical procedure may be performed, especially a surgical procedure involving the lumbar or cervical spine of the patient. Advantageously, the minimally-invasive portal system of the present invention is relatively simple to insert, adjust, and remove, and provides an adequate field of view. 
     In one exemplary embodiment of the present invention, a minimally-invasive portal system for performing a medical or surgical procedure includes an access tube having a selectively adjustable cross-sectional area; and one or more retractor devices each having a first portion and a second portion aligned at a predetermined angle relative to the first portion, wherein the first portion of each of the one or more retractor devices is disposed substantially concentrically with the access tube, and wherein the second portion of each of the one or more retractor devices protrudes substantially beyond a bottom portion of the access tube. 
     In another exemplary embodiment of the present invention, a minimally-invasive portal system for performing a medical or surgical procedure includes an access tube having a selectively adjustable cross-sectional area; a plurality of adjustment mechanisms coupled to the access tube for selectively adjusting the cross-sectional area of the access tube; and one or more retractor devices each having a first portion and a second portion aligned at a predetermined angle relative to the first portion, wherein the first portion of each of the one or more retractor devices is disposed substantially concentrically with the access tube, and wherein the second portion of each of the one or more retractor devices protrudes substantially beyond a bottom portion of the access tube. 
     In a further exemplary embodiment of the present invention, a minimally-invasive method for performing a medical or surgical procedure includes disposing an access tube having a selectively adjustable cross-sectional area at least partially with the body of a patient; and disposing one or more retractor devices each having a first portion and a second portion aligned at a predetermined angle relative to the first portion at least partially within an interior volume defined by the access tube, wherein the first portion of each of the one or more retractor devices is disposed substantially concentrically with the access tube, and wherein the second portion of each of the one or more retractor devices protrudes substantially beyond a bottom portion of the access tube. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention is illustrated and described herein with reference to the various drawings, in which like reference numbers denote like system components or method steps, and in which: 
         FIG. 1  is a cross-sectional side view illustrating one exemplary embodiment of the minimally-invasive portal system of the present invention, the minimally-invasive portal system including an access tube, one or more retractor devices, one or more retaining clips, and a plurality of adjustment mechanisms that assist a user (doctor/surgeon) in visualizing and gaining access to an area within the body of a patient; 
         FIG. 2  is a series of cross-sectional side views illustrating several exemplary steps in the insertion of the minimally-invasive portal system of  FIG. 1 ; 
         FIG. 3  is a planar top view illustrating the minimally-invasive portal system of  FIG. 1 , specifically a single-level configuration of the minimally-invasive portal system; 
         FIG. 4  is another planar top view illustrating the minimally-invasive portal system of  FIGS. 1 and 3 , the figure including the placement of a retractor device; 
         FIG. 5  is a further planar top view illustrating the minimally-invasive portal system of  FIG. 1 , specifically a multi-level configuration of the minimally-invasive portal system; 
         FIG. 6  is a still further planar top view illustrating the minimally-invasive portal system of  FIGS. 1 ,  3 , and  4 , the minimally-invasive portal system incorporating an optional handle attachment; 
         FIG. 7  is a still further planar top view illustrating the minimally-invasive portal system of  FIGS. 1 ,  3 , and  4 , the minimally-invasive portal system incorporating an optional adjustable table attachment; 
         FIG. 8  is a perspective view illustrating one exemplary embodiment of the one or more retaining clips of  FIG. 1 ; 
         FIG. 9  is a cross-sectional side view illustrating one exemplary embodiment of the plurality of adjustment mechanisms of FIGS.  1  and  3 - 7 ; and 
         FIG. 10  is another cross-sectional side view illustrating another exemplary embodiment of the plurality of adjustment mechanisms of FIGS.  1  and  3 - 7 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In various exemplary embodiments, the present invention provides a minimally-invasive portal system that provides enhanced access to and visualization of an area of interest within the body of a human patient, a veterinary patient, or the like, such that a surgical procedure may be performed, especially a surgical procedure involving the lumbar or cervical spine of the patient. Advantageously, the minimally-invasive portal system of the present invention is relatively simple to insert, adjust, and remove, and provides an adequate field of view. 
     Referring to  FIG. 1 , in one exemplary embodiment of the present invention, the minimally-invasive portal system  10  includes an access tube  12  that is selectively positioned through the skin  14  of a patient adjacent to an area of interest (i.e. an area to be operated on or otherwise visualized). Optionally, the access tube  12  may be positioned using one or more conventional dilation tubes, well known to those of ordinary skill in the art, for successively dilating the skin  14  and musculature of the patient to greater diameters or dimensions. Preferably, the access tube  12  has a substantially circular, oval-shaped, square-shaped, or rectangular cross-sectional shape, although other suitable cross-sectional shapes may be utilized. Likewise, the access tube  12  may have any suitable diameter, dimension, and/or depth suitable for the procedure to be performed. 
     One or more retractor devices  16  are selectively disposed concentrically within/through the access tube  12 . Each of the one or more retractor devices  16  includes a top portion  18  which remains external to the body of the patient, a central portion  20  which is disposed concentrically within the access tube  12 , and a bottom portion  22  which is disposed through and protrudes beneath the access tube  12  into the body of the patient. The bottom portion  22  of each of the one or more retractor devices  16  is disposed at a predetermined angle (θ)  24  relative to the central portion  20  of each of the one or more retractor devices  16 , the predetermined angle (θ)  24  varying from about 0 degrees to about 45 degrees, in an exemplary embodiment of the present invention. Optionally, the predetermined angle (θ)  24  is adjustable during the procedure to be performed. It should be noted that the central portion  20  and the bottom portion  22  of each of the one or more retractor devices  16  may be sized and/or shaped such that they fit comfortably within/through the access tube  12  and provide visualization of/access to an exposed area  26  via a portal  28 . Preferably, the top portion  18  of each of the one or more retractor devices  16  includes a post  30  and handle  32 , which may be selectively removable. 
     In use, one or more retaining clips  34  (described in greater detail herein below) may be used to selectively couple the one or more retractor devices  16  to the access tube  12 . Preferably, the access tube  12  incorporates one or more adjustment mechanisms  36  (also described in greater detail herein below). The one or more adjustment mechanisms  36  are each operable for selectively adjusting the diameter or dimensions of the access tube  12 , and, correspondingly, the separation of the one or more retractor devices  16 , the diameter or dimensions of the portal  28 , and the diameter or dimensions of the exposed area  26 , providing visualization and/or access flexibility. 
     Referring to  FIG. 2 , as described above, the access tube  12  may be positioned using one or more conventional dilation tubes  40 , well known to those of ordinary skill in the art, for successively dilating the skin  14  and musculature of the patient to greater diameters or dimensions. The dilation tube(s)  40  is/are first inserted through the skin  14  and musculature of the patient, either singly or successively. The access tube  12  is then disposed concentrically about the dilation tube(s)  40 . Finally, the dilation tube(s)  40  is/are removed, leaving the access tube  12  in place. The one or more retractor devices  16  ( FIG. 1 ) are then inserted (not shown in  FIG. 2 ) and the appropriate adjustments are made using the one or more adjustment mechanisms  36  ( FIG. 1 ). 
     Referring to  FIG. 3 , in another exemplary embodiment of the present invention, the access tube  12  consists of a plurality of segments  50  which are selectively adjustable relative to one another via a plurality of adjustment areas  52 . When adjusted, the plurality of segments  50  of the access tube  12  may separate from one another (as shown in  FIG. 3 ), or they may overlap in the plurality of adjustment areas  52  (not shown in  FIG. 3 ). Alternatively, a portion of one of the plurality of segments  50  may be substantially disposed within and move relative to another one of the plurality of segments  50 . The plurality of segments  50  of the access tube  12  are selectively adjustable relative to one another using the one or more adjustment mechanisms  36  (described in greater detail herein below). Again, the one or more adjustment mechanisms  36  are each operable for selectively adjusting the diameter or dimensions of the access tube  12 , and, correspondingly, the separation of the one or more retractor devices  16  ( FIG. 1 ), the diameter or dimensions of the portal  28 , and the diameter or dimensions of the exposed area  26  ( FIG. 1 ), providing visualization and/or access flexibility. It should be noted that a single-level configuration of the minimally-invasive portal system  10  of the present invention is shown in  FIG. 3 , meaning that there is one adjustment area  52  for any given portion or “side” of the access tube  12 . 
     Referring to  FIG. 4 , the single-level configuration of the minimally-invasive portal system  10  of the present invention is shown with one retractor device  16  in place. Again, each of the one or more retractor devices  16  includes a top portion  18  which remains external to the body of the patient and a central portion  20  which is disposed concentrically within the access tube  12 . Preferably, the top portion  18  of each of the one or more retractor devices  16  includes a handle  32 , which may be selectively removable. The handle  32  allows a user to effectively grasp and manipulate the retractor device  16 . It should be noted that, although one retractor device  16  is shown in  FIG. 4 , more than one retractor device  16  may be used. It should also be noted that the one or more retaining clips  34  ( FIG. 1 ) (described in greater detail herein below) that are used to selectively couple the one or more retractor devices  16  to the access tube  12  are not shown in  FIG. 4 . 
     Referring to  FIG. 5 , in a further exemplary embodiment of the present invention, a multi-level configuration of the minimally-invasive portal system  10  includes a plurality of adjustment areas  52  for one or more portions or “sides” of the access tube  12 , providing enhanced adjustment flexibility. 
     Referring to  FIGS. 6 and 7 , in two still further exemplary embodiments of the present invention, the minimally-invasive portal system  10  includes either a handle attachment  60  ( FIG. 6 ) or a table attachment  70  ( FIG. 7 ) attached to the one or more adjustment mechanisms  36  and/or the access tube  12 . Both the handle attachment  60  and the table attachment  70  protrude substantially upwardly and outwardly from the one or more attachment mechanisms  36  and/or the access tube  12 . The handle attachment  60  allows a user to effectively grasp and manipulate the one or more attachment mechanisms  36  and/or the access tube  12 . Likewise, the table attachment  70  allows the one or more attachment mechanisms  36  and/or the access tube  12  to be securely fastened to an operating table or the like, thereby effectively stabilizing the minimally-invasive portal system  10  of the present invention. 
     Referring to  FIG. 8 , each of the one or more retaining clips  34  includes a body portion  80  and a tongue portion  82 . The body portion  80  of each of the one or more retaining clips  34  is substantially U-shaped, or has another suitable shape for selectively coupling the one or more retractor devices  16  ( FIGS. 1 and 4 ) to the access tube  12  ( FIGS. 1-7 ). The tongue portion  82  of each of the one or more retaining clips  34  defines an opening  84  through which the post  30  ( FIGS. 1 and 4 ) and handle  32  ( FIGS. 1 and 4 ) of each of the one or more retractor devices  16  may pass. In use, the tongue portion  82  of the retaining clip  34  is grasped with the thumb and index finger of the user, advanced downward over the post  30  and handle  32  of the retractor device  16 , and engages/retains the retractor device  16 . 
       FIGS. 9 and 10  show two exemplary embodiments of the adjustment mechanism  36  of the present invention. In general, the adjustment mechanism  36  may consist of an extendable/retractable device that is suitable for selectively adjusting the diameter/dimensions of the access tube  12  ( FIGS. 1-8 ). For example,  FIG. 9  shows an adjustment mechanism  36  that incorporates a screw  90  and a retaining band  92 .  FIG. 10  shows an adjustment mechanism  36  that incorporates a screw  90 , a retaining band  92 , and one or more stabilizing bands  94 . 
     It should be noted that any medically/surgically suitable materials may be used to manufacture the components of the minimally-invasive portal system of the present invention. Such materials are well known to those of ordinary skill in the art and may include, but are not limited to, suitable metals, plastics, and composite materials. 
     Although the present invention has been illustrated and described with reference to preferred embodiments and examples thereof, it will be readily apparent to those of ordinary skill in the art that other embodiments and/or examples may perform similar functions and/or achieve similar results. All such equivalent embodiments and examples are within the spirit and scope of the present invention and are intended to be covered by the following claims.