Patent Publication Number: US-2005119680-A1

Title: Surgical device with a moveable instrument protector

Description:
RELATED APPLICATIONS  
      This application is a continuation of application Ser. No. 10/016,984 entitled Protection System for Surgical Instruments, filed on Dec. 7, 2001, which is incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION  
      The present invention relates in general to surgical devices and more particularly to a surgical device having a protector moveable between an open position exposing an instrument and a closed position covering the instrument.  
     BACKGROUND  
      Surgical devices include a working end or instrument that may be delicate and/or have a sharp point or cutting edge. Examples of such instruments include scalpels, blades, hooks (such as Sinskey hooks, Bonn hooks, insertion hooks, twist hooks and the like), scissors (such as retinal scissors and the like), picks (such as retinal picks and the like), forceps, probes, lens manipulators, markers, collar buttons, choppers, cystotomes irrigation needles and cannulas, spatulas (such as Castroviejo spatulas and the like), and dilators. Most often, these surgical devices include at least one generally cylindrical handle with a distal end that houses instrument. Surgical knives that include a cutting blade at a distal end of the handle are typical of such instruments, and much of the prior art pertaining to protection for such instruments is directed at protection for surgical knives. However, the instant invention applies equally to the protection of non-sharp instruments.  
      Surgical devices typically have a body with a cutting blade or other operable instrument at one end of the body. The end of the body with the instrument sometimes has a portion that tapers down towards the instrument to provide good visibility of the instrument tip. The instruments can be extremely sharp, and the extreme sharpness may render them hazardous when passed back and forth during use in surgical procedures. If the instrument has already been used on the patient, then there is a potential danger of infection since any sharp or tapered instrument can very easily cut or rip through a surgical glove and the skin beneath the glove. Additionally, if the entire surgical device is not sterilized it may introduce infection in the patient.  
      In general, prior art systems for protection of surgical devices include some form of mechanically operable shield that covers the instrument when not in use, and that may be moved or removed in order to expose the instrument during use.  
      For Example, U.S. Pat. No. 5,254,128 to Mesa (incorporated herein by reference) discloses a surgical knife with a blade protector axially moveable between two positions, namely, opened for normal use and closed for storage or safe handling. The blade protector may be fixed in either position. While this arrangement solves some of the limitations of the prior art surgical devices, other common limitations still exist.  
      It is therefore a desire of the present invention to address the limitations and disadvantages of the prior art surgical devices.  
     SUMMARY OF THE INVENTION  
      In view of the foregoing and other considerations, the present invention relates to surgical devices having a movable guard for protecting the device&#39;s instrument.  
      Accordingly, a surgical device is provided. The surgical device includes a body having a reduced diameter portion between a handle portion and a tip portion carrying an instrument, an elongated, substantially cylindrical guard having an end wall forming a first opening for receiving the reduced diameter portion and a second opening formed opposite the first opening, is disposed on the body wherein the end wall portion is slidable along the length of the reduced diameter portion between a closed position with the guard substantially covering the instrument and an open position where the instrument is uncovered. A slot is formed between the first and second openings continuous with the first opening. The surgical device includes a locking mechanism for engaging a portion of the end wall portion for locking the guard in either the closed or open position.  
      The body may be formed of one or more elements, for example, by the interconnection between the tip portion with the reduced diameter portion and the handle portion. The body of the surgical device may be a unitary member, thus reducing costs of manufacturing a multipart body.  
      The locking mechanism may of numerous means known in the art. In a preferred embodiment the locking mechanism includes threads formed on the end wall engageable with a first set and a second set of threads formed on the reduced diameter portion.  
      The guard or the handle may include protrusions formed on the exterior thereof to prevent inadvertent rolling of the device and/or aide in gripping the device. The guard may be sized so that the outside diameter of the guard is substantially the same as the handle portion of the body when the guard is in the open position.  
      The guard may include one or more slots formed between the first and the second opening continuous with the first opening. The elongated slots provide a mechanism for expanding the first opening to prevent over tightening of the guard in a locked position, for facilitating complete cleaning and sterilization of the device and to aide in placing the guard on the body. The guard may include additional openings formed through the guard to facilitate cleaning of the device.  
      The surgical device may include various instruments well known in the art such as, but not limited to, hooks, choppers, collar buttons and blades. The instruments may be non-linear and/or not parallel to the longitudinal axis of the body. The instruments may include one or more bends or angles to facilitate placement of the instrument within the guard when the guard is in the closed position.  
      A method of constructing a surgical device is provided. The method includes the steps of forming a body having a reduced diameter portion between a handle portion and a tip portion, forming a first set of threads on the reduced diameter portion proximate the handle portion and a second set of threads proximate the tip portion, forming an elongated, substantially cylindrical guard having an end wall forming a first opening and a second opening formed opposite the first opening, wherein the end wall portion has end wall threads engageable with the first and second set of threads, forming at least two slots between the first and second opening continuous with the first opening, expanding the diameter of the first opening and passing the tip and second set of threads through the first opening and slidably positioning the end wall portion about the reduced diameter portion, attaching an instrument to the tip, engaging the end wall threads with the second set of threads locking the guard in a closed position with the guard covering the instrument, and engaging the end wall threads with the first set of threads locking the guard in an open position with the instrument uncovered.  
      As with the description of a surgical device above the method may include steps to provide those desired features.  
      The foregoing has outlined the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention.  
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The foregoing and other features and aspects of the present invention will be best understood with reference to the following detailed description of a specific embodiment of the invention, when read in conjunction with the accompanying drawings, wherein:  
       FIG. 1  is a partial cross-section view of a surgical device of the present invention with a moveable guard in the open position;  
       FIG. 2  is a partial cross-section view of a surgical device of the present invention with a moveable guard in the closed position;  
       FIG. 3  is a side view of another surgical device of the present invention;  
       FIG. 3A  is an end view of the moveable guard of  FIG. 3  in isolation;  
       FIG. 4  is a side view of another surgical device of the present invention;  
       FIG. 5  is a side view of a surgical device of the present invention;  
       FIG. 6  is a side view of a surgical device of the present invention;  
       FIG. 7  is a side view of a surgical device of the present invention; and  
       FIG. 7A  is an end view of the moveable guard of  FIG. 7  in isolation.  
    
    
     DETAILED DESCRIPTION  
      Refer now to the drawings wherein depicted elements are not necessarily shown to scale and wherein like or similar elements are designated by the same reference numeral through the several views.  
      As mentioned above, many reusable surgical devices include at least one generally cylindrical handle with a distal end that carries an instrument for performing a medical procedure. Surgical knives, as more fully described below in accordance with preferred embodiments of the present invention, are typical of such reusable surgical devices. Although a surgical knife is illustrated in this specification, those skilled in the art will readily appreciate that the instant invention includes all surgical devices and the instrument that is carried.  
       FIG. 1  is a partial cross-section view of a surgical device of the present invention. The surgical device includes a body  10  carrying an instrument  16  and a protective guard  20 . Body  10  includes a generally cylindrical handle portion  12  aft and a tip portion  14  forward. Tip  14  may have a flat distal end or, as is often the case, a frustoconical distal end. As would be understood by those skilled in the art, tip  14  also includes an appropriate mechanism (not shown) for mounting instrument  16 .  
      Instrument  16  is illustrated as a cutting blade throughout the Figures, however, it should be reliezed that instrument  16  may include any medical instrument, such as, but not limited to, linear and non-linear blades, and linear and non-linear hooks, picks, scissors, picks, forceps, probes, lens manipulators, markers, collar buttons, choppers, cystotomes irrigation needles, cannulas, spatulas and dilators. Blade  16  may be a diamond or other gem, metal or synthetic blade that will, with proper handling, keep a very sharp edge over repeated uses. Blade  16  may include one or more bends or angles so as to be properly aligned with body  10  and so as to be disposed within guard  20  when guard  20  is in the closed position.  
       FIG. 1  also shows a reduced diameter portion  18  of knife body  10  disposed between and interconnected with handle portion  12  and tip  14 . Guard  20  (shown in a locked open position) has an end wall portion  22  forming an opening disposed around reduced diameter portion  18 . In this embodiment, end wall portion  22  includes a locking mechanism shown as interior female threads  24  which engage corresponding locking mechanisms shown as male threads  26  and male threads  28  formed on the exterior of reduced diameter portion  18 . Thus, guard  20  may be rotated to engage threads  24  with threads  26  in order to lock guard  20  in an open position so that the surgical knife may be used normally. In this locked open position, guard  20  generally covers reduced diameter portion  18  in order to form a natural extension of handle portion  12 . As shown in  FIG. 1 , the outside diameter of guard  20  is substantially the same as the outside diameter of handle  12 , such that when guard  10  is in the open position and locking mechanism  24  is engaged a substantially continuous surface with handle  12  is provided.  
      Guard  20  is preferably formed from a translucent material through which a person handling the surgical knife in the safe or locked open position may be able to view the attached blade  16  without the necessity of moving guard  20  to the unsafe or locked open position. This configuration reduces the potential for selecting an improper surgical device during surgery by permitting rapid visual identification of the particular size and type of instrument  16 . This configuration also improves safety during routine handling of the surgical knife by visibly differentiating handle portion  12  from tip  14  carrying blade  16 .  
      As would be understood by those skilled in the art, body  10  and guard  20  should in the preferred, reusable embodiment be formed from hard, durable, and heat resistant plastics, composites, fiber-impregnated resins, or metals. When it is desirable to employ a translucent guard  20  as above, it should be formed from suitable translucent plastics. These types of materials are resistant to the heat and fluids required to clean and sterilize surgical devices after each use.  
       FIG. 2  illustrates the surgical device of the present invention with guard  20  locked in the closed position to protect and cover blade  16 . Guard  20  has been moved forward in the direction of tip  14  of body  10 . From the locked-open position discussed above, the locked-closed position is achieved by counter-rotating guard  20  to disengage threads  24  and  26  so that a user may slide guard  20  forward and engage threads  24  with a second set of threads  28  formed on the exterior of reduced diameter portion  18  forward of first threads  24 .  
      Guard  20  is a generally a cylindrical sleeve having an inside diameter that is slightly greater than the corresponding outside diameter of the generally cylindrical portion of forward tip  14 . When reduced diameter portion  18  is employed, the inside diameter of the opening formed by the end wall portion  22  should be slightly greater than the outside diameter of reduced diameter portion  18 .  
       FIGS. 1 and 2  depict the outside diameter of the generally cylindrical portion of forward tip  14  as having generally the same outside diameter as that of handle portion  12  of knife body  10 . However, it should be readily apparent that the outside diameter of forward tip  14  need not be the same as the outside diameter of handle portion  12 . However, in order to function properly so as to lock guard  20  in a closed position, the outside diameter of tip  14  should be less than the inside diameter of guard  20 . Preferably, when reduced diameter portion  18  is employed, handle portion  12  of body  10  should include at least a portion of larger diameter than the outside diameter of reduced diameter portion  18 . This preferred arrangement facilitates securely locking guard  20  in an open position by forming a screw stop to mechanically prevent end wall portion  22  of guard  20  from extending onto handle portion  12  and past threads  24 . Similarly, the outside diameter of the generally cylindrical portion of forward tip  14  must be larger than the outside diameter of reduced diameter portion  18  to serve as a forward physical stop when guard  20  is in the locked closed or instrument protective position. Moreover, handle portion  12  need not have the same diameter along its entire length; for some embodiments, handle portion  12  might have a tapered configuration (not shown), with the narrow portion of the taper at the end of body  10  opposite blade  16 .  
      In general, the distance between threads  26  and  28  on reduced diameter portion  18  should be sufficient to allow for the length of guard  26  to cover threads  28  when guard  20  is in the locked open position and allow guard  20  to extend somewhat beyond blade  16  when guard  20  is placed in the locked closed position. Similarly, the length of guard  20  is selected so that it will extend beyond blade  16  when in the locked closed position, and is thus dependent upon the length of tip  14  and any mounting for blade  16 , as well as the length of blade  16  when mounted. Once the approximate position of threads  28  (or other locking mechanism) are selected, then the length of guard  20  may be determined; then the position of threads  24  (or other locking mechanism) determined; and finally the length of reduced diameter portion  18  may be determined.  
      Reusable surgical devices must be cleaned and sterilized between uses. As is understood by those skilled in the art, this process typically involves exposing the surgical device to cleaning agents and high temperature sterilization (such as steam autoclaves, etc.). The present invention includes a guard with one or more slots, openings, or gaps therethrough sufficient to expose portions of underlying body  10  to the cleaning mechanisms and sterilizing steam.  FIGS. 3 and 3 A illustrate guard  20  with a slot  30  formed through a wall of the generally cylindrical, sleeve-shaped guard  20 . As would be understood by those skilled in the art with reference to this specification, slot  30  facilitates the entry of cleaning agents and sterilizing steam into the small, otherwise covered spaces under guard  20 , without the need to remove and potentially lose guard  20 . As is illustrated in  FIGS. 4 through 7 A, alternative openings may be formed in guard  20  to serve this same purpose.  
      For example,  FIG. 4  shows multiple slots  30  (designated with the single reference numeral  30 ) formed at different points around the circumference of guard  20  in order to facilitate the flow of cleaning agents and sterilizing steam from several different angles around the circumference of guard  20 . Similarly,  FIG. 5  shows a single slot  30  as shown in  FIG. 3 , but extending through threads  24  of guard  20 . The configuration shown in  FIG. 5  facilitates direct exposure of threads  24  and threads  26  to cleaning and sterilizing agents. A multitude of alternative openings may be provided in different shapes, sizes, and positions in order to facilitate cleaning and sterilizing. Examples are shown in  FIG. 6 , which illustrates a plurality of holes  32  (shown with common reference) in guard  20 , and  FIG. 7 , which illustrates a spiral opening  34 , both of which facilitate cleaning and sterilizing the underside of guard  20 , portion  18 , and threads  24  and  28  (or other locking mechanisms).  
      In an alternative to the embodiment as shown in  FIG. 5  where a slot  30  extends through threads  24  of guard  20 , slot  30  may be extended beyond threads  24 . Such a configuration permits threads  24  on guard  20  to expand if guard  20  is overtightened on body  10 . Expansion of threads  24  on guard  20  permits those threads  24  to “skip” on threads  26  and  28  on body  10 . As a result, guard  20  is protected against overtightening, because excess torque causes threads  24  on guard  20  to loosen relative to corresponding threads  26  or  28  on body  10 . In this way, instrument  16  remains easily accessible. Additionally, slots  30  permit the expanding of the opening in end wall  22  to facilitate placing guard  20  on body  10 , by expanding over or “skipping” over corresponding threads  28 .  
      Because surgical devices, including surgical knives, are typically handled with surgical gloves, guard  20  is preferably provided with a grip. The otherwise smooth outer surface of guard  20  may include a multitude of grips within the scope of the present invention. For example, as is shown in  FIG. 3  and corresponding  FIG. 3A  (end view of guard  20 ), a plurality of ridges  40  may be spaced around the outside circumference of guard  20 . In  FIG. 7  and corresponding  FIG. 7A  (end view of guard  20 ) there is shown a plurality of bumps or nubs  42  dispersed around the outside circumference of guard  20 . Any of the foregoing gripping mechanisms preferably form an exterior surface of guard  20  which is not substantially smooth and cylindrical, and thus forming a surgical device that is easier to manipulate and not prone to inadvertently rolling off a sterile surgical field.  
      As would be understood by those skilled in the art, many different ways exist for assembling guard  20  on body  10 . For example, portion  18  may screw into (or otherwise be fixedly attached to) handle portion  12  at or near threads  26 , thus allowing guard  20  to be positioned on portion  18  prior to attachment to handle portion  12 . Alternatively, guard  20  may be placed on portion  18  prior to attachment of tip  14 . In any event, to prevent loss of guard  20 , the particular mechanism chosen for securing guard  20  onto body  10  should preferably prevent inadvertent removal of guard  20  from body  10  during normal handling. Accordingly, during normal operation, guard  20  stays on body  10  and forms an integral extension of handle portion  12  during use of instrument  16 .  
      Although the foregoing figures and corresponding discussion illustrate threads as a preferred locking mechanism, other locking mechanisms may be employed, such as those disclosed in U.S. Pat. No. 5,254,128 which is incorporated herein by reference. For example, as would be understood by those skilled in the art, the locking mechanism may include two or more grooves formed on the interior of guard  20  that lock guard  20  open or closed by interaction with matching spring-loaded balls. In a similar manner, other types of spring-loaded (coiled spring or leaf spring) detents may be employed to “click” into grooves or notches in order to lock guard  20  into one of its two positions. Other examples not shown would include a bowed leaf spring attached at both ends of a reduced diameter portion, with a rounded projection on their upper-most portion to serve as a spring-loaded detent. In addition, a snap ring arrangement could be used as a detent to “click” into grooves to lock guard  20  into position.  
      From the foregoing detailed description of specific embodiments of the invention, it should be apparent that a surgical device with a moveable instrument protector that is novel has been disclosed. Although specific embodiments of the invention have been disclosed herein in some detail, this has been done solely for the purposes of describing various features and aspects of the invention, and is not intended to be limiting with respect to the scope of the invention. It is contemplated that various substitutions, alterations, and/or modifications, including but not limited to those implementation variations which may have been suggested herein, may be made to the disclosed embodiments without departing from the spirit and scope of the invention as defined by the appended claims which follow.