Abstract:
A method for accessing the interior of a joint, wherein the joint comprises tissue which defines a boundary of the joint, the tissue comprising an interior surface facing toward the interior of the joint and an exterior surface facing away from the interior of the joint, the method comprising: providing a light-emitting needle assembly comprising a hollow needle having a light source at the distal end thereof; and observing the interior surface of the tissue from the interior of the joint as the needle approaches the exterior surface of the tissue.

Description:
REFERENCE TO PENDING PRIOR PATENT APPLICATION 
       [0001]    This patent application claims benefit of pending prior U.S. Provisional Patent Application Ser. No. 62/167,393, filed May 28, 2015 by Pivot Medical, Inc. and Andrew J. Hamel for LIGHT-GUIDED JOINT ACCESS (Attorney&#39;s Docket No. FIAN-109 PROV), which patent application is hereby incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates to surgical procedures in general, and more particularly to arthroscopic procedures. 
       BACKGROUND OF THE INVENTION 
       [0003]    In arthroscopic procedures, access to the interior of a joint is generally provided through narrow cannulas which extend from the surface of the skin, through the intervening tissue, and into the interior of the joint. Arthroscopes and surgical instruments are then passed into and out of the joint space through the cannulas, whereby to enable so-called “keyhole” surgery. See  FIG. 1 . 
         [0004]    It will be appreciated that, in most arthroscopic procedures, at least two portals are used, one to receive the arthroscope (which provides visualization of the internal surgical site) and one to receive the surgical instruments (which are used to perform the surgical procedure at the internal surgical site). In many cases, more than two portals are used. 
         [0005]    It will also be appreciated that, depending on the joint, the specific number of portals used, and the exact locations of those portals, may be limited by the anatomy of the patient. By way of example but not limitation, in hip arthroscopy, it is common for two or three portals to be used, i.e., the first two portals being the so-called anterolateral portal (i.e., the “AL portal”) and either the so-called anterior portal (i.e., the “A portal”) or the so-called mid-anterior portal (i.e., the “MA portal”), while the third portal is typically the so-called distal anterolateral accessory portal (i.e., the “DALA portal”). 
         [0006]    When the first portal is created into the joint, the portal is generally created without the benefit of any internal visualization (i.e., because there is not yet an arthroscope positioned within the joint). 
         [0007]    More particularly, when the first portal is created into the joint, a needle first penetrates from the skin through the intervening tissue structures and into the joint space, then a guidewire is placed through the needle&#39;s lumen into the joint space, next the needle is removed, and then a cannula with a blunt obturator is passed over the guidewire, through the skin, and down into the interior of the joint. Once the first cannula has been advanced into the interior of the joint, the obturator and guidewire are removed from the cannula, and then an arthroscope is advanced down the cannula so that its working end is disposed within the joint. Note that the arthroscope is generally releasably attached to the cannula while the arthroscope is deployed in the joint. 
         [0008]    With the arthroscope deployed within the interior of the joint, the arthroscope may then be used to provide internal visualization during the creation of subsequent portals into the joint. 
         [0009]    More particularly, in hip arthroscopy, the second portal is typically created by using a spinal needle to create a pathway into the joint, and then replacing the spinal needle with a cannula (i.e., in a manner similar to the creation of the first portal, whereby a guidewire is placed through the spinal needle, the spinal needle is removed, and then a cannula is advanced into position over the guidewire). 
         [0010]    During creation of the second portal, the surgeon typically uses the arthroscope (which is already positioned within the joint via the first portal) to view the underside of the capsule of the joint and watch for the spinal needle (which is creating the second portal) engaging, and pushing inwardly on, the capsule, thereby creating an inward tenting effect on the capsule. This inward tenting effect on the capsule can then help the surgeon to confirm the proper positioning of the spinal needle relative to the capsule (i.e., to confirm the proper positioning of the second portal relative to the capsule) before the spinal needle is advanced through the capsule, i.e., by pushing harder on the spinal needle so that the spinal needle penetrates through the tough capsular tissue. 
         [0011]    However, this inward tenting effect on the capsule can often be difficult to visualize (e.g., it may be a nominal tenting effect which can be difficult to detect vis-à-vis the adjacent capsule tissue), and/or it can be difficult to determine the precise needle location simply by viewing the tented tissue (since the tented tissue may have only a generalized curvature and may not present a distinct apex). Difficulty in visualizing a nominal tenting effect on the capsule can result in the surgeon advancing the spinal needle through the capsule at an undesirable location, potentially piercing and damaging tissue structures within the joint with the spinal needle. When this happens, the surgeon must withdraw the spinal needle from the joint, reposition the spinal needle against the exterior of the capsule, and then make another attempt to establish the second portal into the joint. This repositioning of the spinal needle consumes valuable operating room time. Also, incorrect advancement of the spinal needle into the joint creates the potential for the spinal needle to unintentionally pierce the labrum of the hip joint, or to unintentionally scrape the cartilage on the femoral head of the hip joint, either of which creates trauma to important anatomical structures and is a highly undesirable event. 
         [0012]    Therefore, the surgeon needs a better way, when creating the second portal, to determine if the spinal needle is positioned at the correct location prior to piercing through the capsule. 
       SUMMARY OF THE INVENTION 
       [0013]    The present invention provides the surgeon with a better way, when creating the second portal, to determine if the spinal needle is positioned at the correct location prior to piercing the capsule. 
         [0014]    More particularly, in accordance with the present invention, a light source is disposed in the lumen of the spinal needle so that the light source emits light from the distal tip of the spinal needle. As the spinal needle pierces the surface of the skin, passes through the intervening tissue and advances to the outside surface of the capsule, the light from the light source penetrates through the capsule and can be viewed from the underside of the capsule (i.e., by the arthroscope already advanced into the interior of the joint via the first portal) so as to confirm proper positioning of the spinal needle before the spinal needle is advanced through the capsule. 
         [0015]    In one preferred form of the present invention, there is provided a method for accessing the interior of a joint, wherein the joint comprises tissue which defines a boundary of the joint, the tissue comprising an interior surface facing toward the interior of the joint and an exterior surface facing away from the interior of the joint, the method comprising:
       providing a light-emitting needle assembly comprising a hollow needle having a light source at the distal end thereof; and   observing the interior surface of the tissue from the interior of the joint as the needle approaches the exterior surface of the tissue.       
 
         [0018]    In another preferred form of the present invention, there is provided apparatus for providing access to the interior of a joint, the apparatus comprising:
       a light-emitting needle assembly comprising:
           a hollow needle having a distal end, a proximal end and a lumen extending therebetween; and   a light unit comprising a light fiber comprising a distal end and a proximal end;   
           wherein the light fiber of the light unit is disposed at least partially within the hollow needle so that the distal end of the light fiber is disposed adjacent the distal end of the hollow needle, whereby when light is introduced into the proximal end of the light fiber, light will be emitted from the distal end of the light fiber and hence from the distal end of the hollow needle.       
 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0023]    These and other objects and features of the present invention will be more fully disclosed or rendered obvious by the following detailed description of the preferred embodiments of the invention, which is to be considered together with the accompanying drawings wherein like numbers refer to like parts and further wherein: 
           [0024]      FIG. 1  is a schematic view showing a typical arthroscopic procedure; 
           [0025]      FIG. 2  is a schematic view showing a light-emitting spinal needle assembly formed in accordance with the present invention; 
           [0026]      FIG. 3  is a schematic view showing a spinal needle used in the light-emitting spinal needle assembly shown in  FIG. 2 ; 
           [0027]      FIG. 4  is a schematic view showing a light unit used in the light-emitting spinal needle assembly shown in  FIG. 2 ; 
           [0028]      FIG. 5  is a schematic view showing a light-emitting spinal needle assembly engaging the outer surface of the capsule of a joint; 
           [0029]      FIG. 6  is a schematic view showing a light-emitting spinal needle assembly penetrating the capsule of a joint; 
           [0030]      FIG. 7  is a schematic view showing a light-emitting spinal needle assembly oriented toward the femoral head as it engages the outer surface of the capsule of a joint; 
           [0031]      FIG. 8  is a schematic view showing a light-emitting spinal needle assembly oriented toward the labrum as it engages the outer surface of the capsule of a joint; and 
           [0032]      FIG. 9  is a schematic view showing a light-emitting spinal needle assembly oriented toward the labrum prior to engagement with the outer surface of the capsule of a joint. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0033]    The present invention provides the surgeon with a better way, when creating the second portal, to determine if the spinal needle is positioned at the correct location prior to piercing the capsule. 
       Light-Emitting Spinal Needle Assembly 
       [0034]    More particularly, in one preferred form of the invention, there is provided a light-emitting spinal needle assembly  5  ( FIG. 2 ) which generally comprises a spinal needle  10  ( FIG. 3 ) and a light unit  15  ( FIG. 4 ). 
         [0035]    Spinal needle  10  ( FIG. 3 ) is a conventional spinal needle (or similar needle) comprising a shaft  20  having a distal end  25  terminating in a sharp point, a proximal end  30  and a lumen  35  extending therebetween. 
         [0036]    Light unit  15  ( FIG. 4 ) preferably comprises a handle  40  housing light-emitting element  45  (e.g., an LED) which is powered by a portable power supply  50  (e.g., a battery). A light fiber  55  extends distally out of handle  40 . More particularly, light fiber  55  comprises a proximal end  60  disposed adjacent to light-emitting element  45  and a distal end  65  for insertion into spinal needle  10  as will hereinafter be discussed. Light fiber  55  is configured so that light introduced into the proximal end  60  of light fiber  55  is delivered to, and is emitted from, distal end  65  of light fiber  55 . 
         [0037]    Light fiber  55  of light unit  15  ( FIG. 4 ) is disposed within spinal needle  10  ( FIG. 3 ) so as to together form light-emitting spinal needle assembly  5  ( FIG. 2 ). More particularly, light fiber  55  of light unit  15  extends through lumen  35  of spinal needle  10  so that distal end  65  of light fiber  55  is positioned at (or near) the distal end  25  of spinal needle  10 , with proximal end  30  of spinal needle  10  mating with handle  40  of light unit  15 , whereby to form the complete light-emitting spinal needle assembly  5 . In this way, the distal end of light fiber  55  acts as a light source for emitting light from the distal end of light-emitting spinal needle assembly  5 . Distal end  65  of light fiber  55  may be shaped so as to form a lens in order to project the light emitted by light fiber  55  (e.g., shaped as a convex lens in order to provide a diverging light beam) and/or one or more lenses may be provided at the distal end of light fiber  55  in order to project the light emitted by light fiber  55 . 
         [0038]    In one preferred form of the invention, proximal end  30  of spinal needle  10  mates with handle  40  of light unit  15  via a luer lock-type connecter or another type of connecter. 
         [0039]    Note that in one preferred form of the invention, distal end  65  of light fiber  55  is substantially flush with, or minimally proximal to, the distal end of spinal needle  10  so that the distal end of the light fiber acts as a stylet for the hollow spinal needle, whereby to prevent tissue coring (e.g., in a manner similar to how a stylet is normally used with a spinal needle). In any case, however, distal end  65  of light fiber  55  is disposed so that light emitted by the distal end of the light fiber  55  projects out the distal end of spinal needle  10 . 
         [0040]    Thus it will be seen that light-emitting spinal needle assembly  5  generally comprises a spinal needle having a light fiber disposed in its lumen, with the light fiber being illuminated at its proximal end with a light-emitting element so that light is emitted from the distal tip of the spinal needle. 
         [0041]    The light provided by light unit  15  is preferably a high-intensity, “tight beam” light emission so that a point source of light is visible through the capsule (as opposed to a low-intensity, “diffused” light emission which would be difficult to see through the capsule). The light provided by light unit  15  can be of any wavelength or wavelengths capable of being detected by an arthroscope, but the light preferably comprises one or more infrared (IR) or near-infrared (near-IR) wavelengths, since IR and near-IR wavelengths are generally more effective in penetrating tissue than shorter wavelengths. 
       Using the Light-Emitting Spinal Needle Assembly to Provide Light-Guided Joint Access 
       [0042]    Light-emitting spinal needle assembly  5  may be used to provide light-guided joint access. 
         [0043]    More particularly, a first portal is formed into the joint and then an arthroscope is advanced through the first portal and into the interior of the joint. Then, with light fiber  55  disposed within lumen  35  of spinal needle  10 , and with light emitting element  45  energized so that light is emitted from distal end  25  of spinal needle  10 , the spinal needle is advanced through the skin, passed through the intervening tissue and placed up against the outside of the capsule. Note that the surgeon can “feel” the engagement of the spinal needle with the capsule due to the tactile feedback experienced by the surgeon during advancement of the spinal needle, inasmuch as the capsule comprises significantly denser tissue than the intervening tissues (such as muscle and fat) and hence provides greater resistance to penetration. The light emitted from the distal end of the spinal needle will pass through the capsule and can (when the spinal needle is correctly positioned against the capsule) be viewed from the underside of the capsule (i.e., by the arthroscope previously advanced into the interior of the joint via the first portal). See  FIG. 5 . 
         [0044]    If the spinal needle is correctly located in the gap between the femoral head and the labrum, such as is shown in  FIG. 5 , the spinal needle is advanced through the capsule and into the interior of the joint. See  FIG. 6 . 
         [0045]    However, if the spinal needle is not located in the gap between the femoral head and the labrum (see, for example,  FIG. 7 , where the spinal needle is oriented towards the femoral head, and  FIG. 8 , where the spinal needle is oriented toward the labrum), the surgeon will not see the light from the light unit disposed in the spinal needle. The surgeon will, therefore, know that the spinal needle is not positioned in the correct location, and the surgeon will reposition the spinal needle on the outside of the capsule until the light emitted from the distal end of the spinal needle can be seen with the arthroscope ( FIG. 5 ). Many times this can be done without withdrawing the spinal needle all the way back out of the skin, inasmuch as the skin and the intervening tissue are fairly elastic and typically permit such repositioning of the spinal needle. 
         [0046]    Once it is confirmed that the light emitted from the distal end of the spinal needle is in the preferred location (e.g., in the gap between the femoral head and the labrum, such as shown in  FIG. 5 ), the surgeon will know that the spinal needle is positioned in the correct location and the surgeon will proceed to advance the spinal needle through the capsule ( FIG. 6 ). Light unit  15  is then disconnected from spinal needle  10  and removed. A guidewire is then advanced into the spinal needle, and then the spinal needle is replaced with a cannula, etc., whereby to complete creation of the second portal into the joint. 
         [0047]    It will be appreciated that by providing the spinal needle with a light source which is visible through the capsule, the spinal needle may be passed through the capsule with increased precision, since the light source provides a visually distinct and highly accurate indication of needle position prior to passing the needle through the capsule. 
         [0048]    It should be appreciated that it is not necessary for the distal end of light-emitting spinal needle assembly  5  to be in actual engagement with the outer surface of the capsule in order for the light emitted by the distal end of the spinal needle to be detected by an arthroscope located within the interior of the joint—in general, as long as the assembly has a light source of sufficient intensity, the approaching spinal needle can be detected prior to its actual engagement with the outer surface of the capsule. This feature allows the orientation of the spinal needle to be adjusted earlier in its advancement. 
         [0049]    By way of example but not limitation, if the spinal needle is located off to the side of the gap between the femoral head and the labrum, some light from the light source may still be visible to the arthroscope while the spinal needle is displaced from the capsule, so that the surgeon will know in which direction the spinal needle should be re-positioned. For example, if the spinal needle is positioned over the labrum but is not in the gap between the labrum and femoral head ( FIG. 9 ), a glow of light may be visible from the distal end of the spinal needle; this indicates the location of the spinal needle to the surgeon, so that the surgeon can then re-position the spinal needle in the desired location. In other words, where the spinal needle has a light source within the needle, the surgeon will do less “searching” for the desired location than where the spinal needle lacks a light source within the needle, thereby reducing the time needed to establish the portal. Additionally, a properly-positioned spinal needle having a light source will always be visible through the capsule and thus be a more reliable means to identify needle location prior to piercing the capsule, thereby reducing the chance that the spinal needle either penetrates the labrum or unintentionally scrapes the cartilage on the femoral head. 
       Additional Aspects of the Present Invention 
       [0050]    Additionally, the light provided by light unit  15  can be continuous light or flashing/strobing light. 
         [0051]    The “spot size” of the light source provided at the distal end of light fiber  55  can be variable such that the “spot size” of the light source can go from broad to focused (e.g., like a laser pointer) as the spinal needle gets closer to the joint. 
         [0052]    Also, it will be appreciated that light-emitting element  45  (e.g., an LED) might be powered by an external power source (e.g., a power cable extending from a power console or from a wall plug). Alternatively, the light-emitting element  45  supplying light to the proximal end of light fiber  55  might not be carried by handle  40 , e.g., light-emitting element  45  might be housed in a separate light source console and coupled to the proximal end of light fiber  55  by an optical cable. In this form of the invention, light fiber  55  is still connected to proximal end  30  of spinal needle  10  such that light fiber  55  can be disconnected from spinal needle  10  after spinal needle  10  has penetrated the capsule. 
         [0053]    It will be appreciated that in the foregoing example, and as seen in  FIGS. 1 and 5-9 , the first portal is preferably created at the AL portal, and the second portal is preferably created at either the A portal or the MA portal. 
         [0054]    Further, it will also be appreciated that the present invention can be utilized to create portals into other joints, e.g., the shoulder joint, the knee joint, etc. 
       MODIFICATIONS 
       [0055]    It should be understood that many additional changes in the details, materials, steps and arrangements of parts, which have been herein described and illustrated in order to explain the nature of the present invention, may be made by those skilled in the art while still remaining within the principles and scope of the invention.