Abstract:
A disposable plastic vaginal speculum constructed for heavy duty use and/or for long duration gynecological procedures including vaginal surgical and electrosurgical procedures. The hinge region of the speculum is reinforced so that the speculum can bear forces of a magnitude normally bearable only by metal vaginal specula. The reinforcing element also functions as a smoke evacuation element.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to the field of disposable vaginal specula. 
       BACKGROUND OF THE INVENTION 
       [0002]    Disposable, plastic vaginal specula are known. They are often formed of a moldable synthetic resin, such as polystyrene or polypropylene, and can be transparent or opaque, clear or colored. 
         [0003]    Disposable vaginal specula are particularly useful for high-volume users, such as clinics which specialize in the detection of venereal disease or cervical cancer. Because of the large number of women being examined, it is advantageous to have a low-cost, disposable instrument obviating the need for cleaning and sterilization of the instrument after use. This is particularly true with the increase in occurrence of sexually transmitted diseases such as AIDS. 
         [0004]    Gynecologists prefer plastic specula as they are more user-friendly, not being cold to patients as metal specula are. Additionally, metal specula have to be polymer coated for thermal and electric insulation when used for electrosurgical procedures. Any uncoated metal speculum may lead to serious accidents causing burns when such procedures are performed. Similarly, any damage to the polymer coat may result in serious clinical harm to the patient. Therefore, plastic specula are generally preferred by physicians, but such specula must be sufficiently strong and unbreakable during use, as discussed herein below. 
         [0005]    Because the practitioner or clinician should have both hands free during an examination, a vaginal speculum is preferably lockable at any of several open positions, and then easily released for removal. However, there are problems in constructing plastic specula which can reliably remain in an open, locked position. When pressure is exerted on the speculum&#39;s blades by the vaginal wall, the locking parts or blades of the speculum can distort. It is known that plastic specula do not possess the required mechanical strength for all medical procedures. Heavy duty procedures such as in vitro fertilization (IVF) and procedures on obese patients are generally not performed using plastic specula because of their tendency to fracture at loads greater than about 2 to 3 kg. The fractured plastic generates sharp pieces with a concomitant risk of injury to the patient. 
         [0006]    Another problem of prior-art disposable vaginal specula is that they often produce noisy clicks when being opened within the patient. This noise is caused by the ratchet action of the speculum&#39;s locking mechanism. Although the ratchet action itself is not harmful, the clicking noise is often disturbing to the patient. It sometimes causes an involuntary response on the part of the patient, often leading to sudden increases in pressure on the speculum causing it to break. 
         [0007]    Typical plastic vaginal specula are disclosed, for example, in U.S. Pat. Nos. 3,568,665; 3,752,149; 3,246,646; 3,332,414; 3,650,266; 3,985,125, 3,890,961 and US Publ Pat Appl. 2009/177044. 
         [0008]    Various gynecological surgical procedures have recently been developed based on electrosurgical and laser technologies. Among these surgical techniques are those involving gynecological procedures such as, for example, hysterectomies and surgical treatment of cervical cancers. During these types of gynecological procedures, a vaginal speculum is typically employed to dilate the vaginal cavity so that the uterus or cervix may be operated upon in an unobstructed manner. Electrosurgical tools are then inserted through the speculum and the surgical procedures are carried out. 
         [0009]    Electrosurgical techniques often involve vaporization of tissue which necessarily produces smoke. This smoke can obscure the surgeon&#39;s view of the area undergoing surgery. In the area of gynecological surgery, vaginal specula including tubes for removing the smoke produced by electrosurgical procedures have been suggested. One such device is disclosed in U.S. Pat. No. 4,884,559 to Collins. The Collins speculum includes a lower blade and an upper blade and is provided with a separately mounted smoke tube or an internally formed hollow, each of which extends over substantially the entire length of the upper blade. The smoke evacuating tube is attached to the concave portion of the upper blade using inserts. 
         [0010]    Similarly, U.S. Pat. No. 5,499,964 to Beck teaches a U-shaped channel member positioned adjacent to the contoured inner surface of the upper blade member of a speculum. The U-shape channel member is configured to snap fit into the upper blade forming a channel through which the smoke produced by the gynecological procedure is withdrawn. 
         [0011]    U.S. Pat. No. 2,483,233 to Price et al teaches a speculum with an air tube that is welded to the speculum and is used as an air path for evacuating smoke from a gynecological electrosurgical procedure. 
         [0012]    Prior art vaginal specula incorporating smoke evacuation systems have employed smoke tubes that are either welded or soldered to metal specula, solvent bonded to plastic specula blades, or in the case of the Collins device, require additional fasteners spaced along the upper blade. These tube systems have limited rates of evacuation due to relatively small tube diameters and require fastening means which involves added assembly time and/or manufacturing expense. 
         [0013]    In view of the above remarks it would be advantageous to develop a sturdy plastic vaginal speculum which would not fracture or collapse under loads normally encountered during examinations of long duration or during extended gynecological surgical procedures. Additionally, a robust plastic speculum equipped with a low cost, easily manufactured and applied smoke evacuator member would be desirable. Most desirable would be a speculum solving both such problems simultaneously. 
       SUMMARY OF THE PRESENT INVENTION 
       [0014]    It is an object of the present invention to provide a sturdy disposable vaginal speculum that allows for the performance of long-duration, heavy duty medical procedures. 
         [0015]    It is a further object of the present invention to provide a safe, substantially non-breakable, disposable speculum that can withstand loads in excess of about 2 to 3 kg, preferably in excess of 6 kgs. 
         [0016]    It is yet a further object of the present invention to rapidly evacuate smoke from a site undergoing electrosurgical gynecological procedures so that the surgeon&#39;s view of the site is not obscured during the procedures. 
         [0017]    An additional object of the present invention is to evacuate smoke through a vaginal speculum including an illumination system for illuminating an area undergoing surgery so that light illuminating the area under surgery is not obscured by the smoke. 
         [0018]    These and other objects of the present invention may be readily understood from the discussion below and the Figures shown herein. 
         [0019]    In one aspect of the present invention, there is provided a vaginal speculum which includes a plastic dorsal member, a plastic ventral member and an insert support element. The plastic dorsal member has a distal end and a proximal end and includes: i. a rounded dorsal blade member with concave and convex surfaces; ii. a dorsal handle, and iii. a pair of lateral wall elements connecting between, and formed integrally with, the blade member and the handle so as to form an inspection aperture between the concave surface of the blade member and an opposing portion of the handle. Each wall element has formed therewith a first hinge portion. The plastic ventral member includes: i. a rounded ventral blade member; and ii. a ventral handle having a portion adapted to fit between the lateral wall elements of the dorsal member and having formed thereon a pair of second hinge portions adapted for interconnection with the first hinge portions. The first and second hinge portions form a hinge between the dorsal member and the ventral member for facilitating relative angular translation between these members. The insert support element is in mechanical connection with the proximal end of the dorsal blade member, arranged within the inspection aperture, and configured to extend within the concave surface of the dorsal blade member so as to cooperate therewith to form a channel for the evacuation of smoke or detritus produced by a gynecological procedure when suction from a suction source is applied. The support element is also in load-bearing arrangement with a predetermined one of the first or second pairs of hinge portions, thereby reducing the likelihood of shear stress induced mechanical failure of the dorsal member when in use. 
         [0020]    Relative angular rotation of the speculum is effected about an axis extending transversely through the hinge, adapted to support thereat shear force components normal to the axis above the hinge. 
         [0021]    The insert support element includes: i. a seat having a proximal portion formed to fit within the concave surface of the dorsal blade element, the seat having a distal portion extending generally away from the inspection aperture; and ii. a pair of lateral fenders extending generally transversely away from the seat along the pair of lateral wall elements so as to be in load-bearing arrangement with the hinge. This reduces the likelihood of shear stress induced mechanical failure of the speculum when in use. Forces acting on the hinge are partially transferred by the fender elements to the arched proximal end of the dorsal blade member. 
         [0022]    In some embodiments of the vaginal speculum, the insert support element further includes a hollow nipple adapted for connection to a suction source to evacuate smoke and/or detritus produced as a result of the gynecological procedure. 
         [0023]    In yet other embodiments of the speculum, the insert support element further includes a retainer ring through which an electrical connection of a light source or an optical instrument may be positioned. 
         [0024]    In further embodiments of the speculum, the speculum is formed of a high stress resistant plastic suitable for supporting stresses in excess of at least a force of 6 kgs without bending and without fracturing. 
         [0025]    In another embodiment of the speculum, each of the first hinge portions includes a hinge pin and each of the second hinge portions includes a hinge hole. In yet other embodiments, each of the second hinge portions includes a hinge pin and each of the first hinge portions includes a hinge hole. 
         [0026]    In yet another embodiment of the speculum, each of the lateral wall elements of the dorsal member includes a hinge pin lead slot leading to the hinge holes from the distal edge of the lateral wall elements along their inside surfaces. 
         [0027]    In a further embodiment of the vaginal speculum, the dorsal blade member and the dorsal handle member are integrally joined and form an arcuate region at the proximal end of the dorsal blade member. 
         [0028]    In another embodiment of the speculum, the forces acting on the hinge portions are transferred by the fender elements to the arcuate region of the seat, the arcuate region of the seat, at least partially supporting the arcuate region at the proximal end of the dorsal blade member. 
         [0029]    In another embodiment of the speculum, shear forces acting on the hinge portions are dispersed therefrom because of the greater area of the speculum upon which they act above the hinge region than below it. This greater area is a result of the fender elements being positioned essentially above the hinge region. 
         [0030]    In still another embodiment of the vaginal speculum of the invention, the second hinge portions are hinge pins and the first hinge portions are elongated grooves fitted with a ratchet mechanism into which the hinge pins are inserted. 
         [0031]    In still other embodiments of the vaginal speculum, the speculum contains a locking mechanism in mechanical communication with the dorsal and ventral handle members operable to lock the dorsal blade member and the ventral blade member in a user-selected position with respect to each other. 
         [0032]    In some embodiments of the speculum, the locking mechanism includes an at least partially threaded screw that is joined to and extends from the dorsal handle member through the ventral handle member. The screw has a nut positioned on it for holding the ventral and dorsal blade members in a predetermined user-selected position with respect to each other. 
         [0033]    In other embodiments of the speculum, the locking mechanism is a trigger mechanism in mechanical communication with the dorsal and ventral handles. The trigger mechanism is operable to lock the handles so that the dorsal and ventral blade members remain in a user selected position with respect to each other. The trigger mechanism includes a trigger element configured so that when pressed in a first direction the trigger element is operative to lock the ventral and dorsal handles, preventing rotation and/or translation of the blade members. When pressed in a second direction the trigger element is operative to unlock the handles, allowing rotation and/or translation of the blade members. In some embodiments of the trigger mechanism, the mechanism includes: a pair of substantially parallel positioning projections, the projections separated from each other by a predetermined distance and projecting generally transversely from the dorsal handle in a distal direction; and a trigger element having a proximal press end and a distal wedge end, the wedge end being formed to be thicker than the remaining sections of the trigger element. When the press end is pressed in a first direction the wedge end is moved between the positioning projections and wedged between the projections, thereby locking the ventral and dorsal handles, preventing rotation and/or translation of the blade members. When the press end is pressed in a second direction the wedge end moves out of, and away from, the positioning projections unlocking the ventral and dorsal handles, allowing rotation and/or translation of the blade members. 
         [0034]    In another aspect of the present invention, there is provided an insert support element for use with a vaginal speculum, the speculum configured to include an inspection aperture, hinge pins forming part of a hinge and a dorsal blade element having a concave surface. The insert support element includes: i. a seat having a proximal portion formed to fit within the concave surface of the dorsal blade member and having a distal portion extending generally away from the inspection aperture; and ii. a pair of lateral fenders extending generally transversely away from the seat so as to be in load-bearing arrangement with the hinge pins of the speculum. This reduces the likelihood of shear stress induced mechanical failure of the speculum when in use. The distal portion and the proximal portion of the seat are configured so as to cooperate with the concave surface of the dorsal blade member of the speculum to form a channel for the evacuation of smoke or detritus produced by a gynecological procedure when suction from a suction source is applied. 
       DEFINITIONS 
       [0035]    Ventral member—In the specification below this member of the speculum may also be described as the fixed member or the lower member. 
         [0036]    Dorsal member—In the specification below, this member of the speculum may also be described as the movable member or the upper member. 
         [0037]    Proximal—the direction closest to the user of the speculum. 
         [0038]    Distal—the direction furthest from the user of the speculum 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0039]    The invention is herein described, by way of example only, with reference to the accompanying drawings. With specific reference now to the drawings in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of the preferred embodiments of the present invention only. They are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in greater detail than is necessary for a fundamental understanding of the invention. The description taken with the drawings make apparent to those skilled in the art how the several forms of the invention may be embodied in practice. 
           [0040]    In the drawings: 
           [0041]      FIG. 1A  is an isometric view of a disposable speculum constructed according to an embodiment of the present invention, the speculum being in its open configuration; 
           [0042]      FIG. 1B  is a side view of a disposable speculum constructed according to the embodiment in  FIG. 1A , the speculum being in its closed configuration; 
           [0043]      FIG. 2  is a front view of the blade profile of the disposable speculum of  FIGS. 1A and 1B , the speculum being in its closed configuration; 
           [0044]      FIG. 3  is an isometric view of the ventral member of the speculum shown in  FIGS. 1A and 1B ; 
           [0045]      FIG. 4A  is an isometric view of the insert support element of the speculum shown in  FIGS. 1A and 1B ; 
           [0046]      FIG. 4B  is a side schematic view of the insert support element of the speculum shown in  FIGS. 1A and 1B ; 
           [0047]      FIG. 5  is an isometric view of the insert support element shown in  FIGS. 4A and 4B  outfitted with a light source; 
           [0048]      FIG. 6A  is a view of the forces acting on the hinge region of the speculum shown in  FIGS. 1A and 1B  and their transfer therefrom; 
           [0049]      FIG. 6B  is a view of the speculum in  FIGS. 1A and 1B , connected to a suction source, the Figure showing the axes used in  FIG. 6C ; 
           [0050]      FIG. 6C  shows cross-sectional views along axes AA′ and BB′ of  FIG. 6 ; 
           [0051]      FIG. 7  is a side view of a speculum in its open configuration constructed according to another embodiment of the present invention; 
           [0052]      FIGS. 8A-8C  are side, isometric and proximal views, respectively, of an insert support element usable with the speculum in  FIG. 7 ; 
           [0053]      FIG. 8D  shows the relationship between the dorsal blade of the speculum in  FIG. 7  and the insert support element of  FIGS. 8A-8C ; 
           [0054]      FIGS. 9A-9B  are side and isometric views, respectively, of a lock element used with the speculum shown in  FIG. 7 ; 
           [0055]      FIGS. 10A-10B  present the lock element of  FIGS. 9A and 9B  as it is positioned in the speculum of  FIG. 7 ; 
           [0056]      FIGS. 11A-11B  show the lock element of  FIGS. 9A-9B  in its unlocked and locked position, respectively; and 
           [0057]      FIG. 12  is a proximal view of the speculum shown in  FIG. 7 . 
       
    
    
       [0058]    Similar elements in the Figures are numbered with similar reference numerals. 
       DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0059]    Currently available disposable plastic vaginal specula are structurally too weak to be employed for anything other than routine short-duration examinations, including examinations where vaginal or cervical smears are obtained. In heavy duty and/or long-duration gynecological surgical procedures, a patient may reflexively or otherwise generate sudden large mechanical loads on the plastic device resulting in its fracturing. Additionally, if the plastic vaginal speculum must be held open for relatively long durations, blade bending and even collapse may occur. Changes are therefore required in the construction of plastic specula so that they may tolerate actual encountered loads. 
         [0060]    Currently available plastic specula may support loads of up to about two to three kilograms. Since structural failure is so common with plastic specula, many, if not most, plastic specula designs have been withdrawn from the market incurring the wrath of regulatory agencies such as the FDA. 
         [0061]    The present invention teaches a disposable plastic speculum that includes an insert support element that also provides for easy withdrawal of smoke generated by electrosurgical and laser ablation gynecological procedures. The physician then may easily proceed with his/her gynecological examination without obstruction by smoke and detritus. The insert support element also provides additional structural strength to the plastic speculum allowing such specula to support loads in excess of about six kilograms over sustained periods. These loads are similar to those supported by metal specula. 
         [0062]    Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting. 
         [0063]    It is to be appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination. 
         [0064]    Reference is now made to  FIGS. 1A-6C  in which an embodiment of a disposable speculum  10  and a novel insert support element  60  is shown.  FIGS. 1A-1B  are isometric and side views, respectively, of speculum  10  in its open and closed configurations, respectively;  FIG. 2  is a front view of the blade profile of disposable speculum  10  in its closed configuration;  FIG. 3  shows an isometric view of the ventral member of the speculum in  FIGS. 1A and 1B ;  FIGS. 4A and 4B  are isometric and side views, respectively, of an insert support element of speculum  10  in  FIGS. 1A and 1B ;  FIG. 5  is an isometric view of the insert support element of speculum  10  shown in  FIGS. 1A and 1B  outfitted with a light source; and  FIGS. 6A-6C  show how the forces acting on speculum  10  may be dispersed when speculum  10  is used. 
         [0065]    Reference is now made to  FIGS. 1A and 1B . Speculum  10  shown therein is formed of an injection molded plastic, in the present invention a high strength plastic, such as polycarbonate. Other resins possessing similar mechanical strength my also be used to form the specula of the present invention. In all events, the plastic must be stronger and more durable than the currently employed polystyrene or polypropylene. Typically, the plastic is a clear transparent plastic but colored or non transparent high strength plastics may also be used. 
         [0066]    Speculum  10  is formed of a dorsal member  112  and a ventral member  114 . Dorsal member  112  contains: a dorsal blade member  12 ; a dorsal handle  26  integrally formed with blade member  12 ; a pair of hinge pin holes (not shown) one on each lateral wall  61  of dorsal member  112  and each positioned to receive a hinge pin  16  (discussed below); and a dorsal member bolt hole  28  typically formed as an integral extension from dorsal handle  26 . In other embodiments, bolt hole  28  may be formed directly in handle  26  without need of a structural extension. 
         [0067]    Ventral member  114  includes: a ventral blade member  14 ; a ventral handle  24  integrally formed with blade member  14 ; and integrally formed hinge pins  16 , one on each side of ventral member  114  near its proximal end. Hinge pins  16  can also be formed as studs, trunnions and the like. Hinge pins  16  are insertable into the hinge pin holes (not shown) on dorsal member  112  described above, thereby engaging dorsal and ventral members  112  and  114  so that speculum  10  is ready for use. Hinge pins  16  and hinge pin holes (not shown) form a hinge around which dorsal blade member  12  pivots when speculum  10  is brought from its closed to its open configuration or vice-versa. In the closed configuration, dorsal blade member  12  lies facing and substantially adjacent to ventral blade member  14  as shown in  FIG. 1B . 
         [0068]    In  FIGS. 1A and 1B , insert support element  60 , discussed in greater detail below in conjunction with  FIGS. 4A and 4B , is shown with broken lines. 
         [0069]    In  FIG. 2 , to which reference is now made, a front profile of blade members  12  and  14  of speculum  10  discussed in conjunction with  FIGS. 1A ,  1 B and  3  below is shown. The blade members are in their closed configuration. Seat  62  of insert support element  60  also discussed below is shown. Seat  62  and the concave side of dorsal blade member  12  form a channel through which smoke and other detritus may be evacuated from speculum  10 . 
         [0070]    Returning once again to  FIGS. 1A and 1B , in some embodiments there is a hinge pin lead notch (not shown) integrally formed on each of the inside faces of lateral wall elements  61  of dorsal member  112 . The inside surface of each of lateral wall elements  61  is the surface that partially defines inspection aperture  63 . The notch typically runs from a hinge pin hole (not shown) to a point on the distal edge of lateral wall elements  61  of dorsal member  112 . The notch is intended to allow for easier positioning of hinge pins  16  in their respective hinge pin holes by sliding pin  16  along the notch until it enters its corresponding hinge hole. Without intending to limit the invention, the hinge pin lead notches may be made by using the side core method of injection molding. 
         [0071]    An at least partially threaded bolt or screw  20  extends into and through dorsal member bolt hole  28  and then into at least one ventral member bolt hole  34  (better seen in  FIG. 3 ) in ventral handle  24 . In  FIG. 1A , bolt or screw  20  makes an approximately right angle turn after extending from dorsal member bolt hole  28 , entering ventral member bolt holes  34  on ventral handle  24 . Without intending to be limiting, the bolt or screw is typically made of a plastic, such as nylon, polyethylene, polypropylene, acetal (polyoxymethylene) and polycarbonate. The bolt or screw may have a splayed end as best seen in  FIGS. 1A and 1B  which after passing through ventral member bolt holes  34  expands to engage and hold the bolt or screw to ventral handle  24 . Other methods of engagement known to those skilled in the art may also be used. In other embodiments, bolt or screw  20  may pass directly from dorsal member bolt hole  28  to a single ventral member bolt hole  34  without requiring a right angle turn. In such an embodiment, holes  28  and  34  may be integrally formed directly within dorsal handle  26  and vertical handle  24 , respectively, without need for any extensions from the handle members. Such a lock mechanism may be denoted as a key lock mechanism. 
         [0072]    Plastic nut  18  sits on the side of dorsal member bolt hole  28  distal from ventral handle  24 . After speculum  10  is brought from its closed configuration substantially as in  FIG. 1B  to its partially or completely open configuration as in  FIG. 1A , nut  18  is used to lock the handles in the position desired by the physician while he carries out the required gynecological procedures. 
         [0073]    Nut  18  and threaded bolt or screw  20  together form a locking mechanism and may be described herein as such. It should be evident to one skilled in the art that a nut and bolt mechanism is not the only locking mechanism that can be used and therefore its use here should not be deemed to be limiting. 
         [0074]    While what has been described herein has described a locking mechanism employing a threaded bolt or screw  20  extending from dorsal handle  26  to the ventral handle  24 , other locking mechanisms readily known to those skilled in the art can also be used. Additionally, we have described a bolt or screw mechanism that reaches from the dorsal handle member to the ventral handle member entering the latter from the side after making a right angle turn. It should readily be understood by one skilled in the art that a direct connection can be effected where the screw or bolt passes through a single integrally formed bolt hole on each of the handles without making a right angle turn. 
         [0075]      FIG. 3  to which reference is now made shows an isometric view of the ventral member  114  of the speculum shown in  FIGS. 1A and 1B . The elements in the Figure are numbered as in  FIGS. 1A and 1B  but because the ventral member  114  is shown alone, identification of the elements are clearer. This is particularly true of hinge pins  16  and ventral member bolt hole  34 . 
         [0076]      FIGS. 4A and 4B  show isometric and side views of insert support element  60  which is constructed to be positioned near the concave side of dorsal blade member  12 . The concave and convex sides of dorsal blade member  12  and ventral blade member  14  are substantially as shown in the profile view of blade members  12  and  14  that appear in  FIG. 2 . In  FIGS. 1A and 1B  discussed above, insert support element  60  is shown with broken lines. 
         [0077]    As shown in  FIGS. 4A and 4B , insert support element  60  may be substantially saddle-shaped where fenders  66  extend from both sides of seat  62  substantially transversely. Protruding from the proximal portion of seat  62  is nipple  70 . At the end of fenders  66  are engagement prongs  64  bounding fender notch  65  that can detachably engage with hinge pins  16  of ventral member  114 . In some embodiments, holes of a diameter suitable for detachably engaging hinge pins  16  may be used instead of engagement prongs  64  and fender notch  65 . Fenders  66  of insert support element  60  are positioned between ventral member  114  from which hinge pins  16  extend and dorsal member  112  in which hinge pin holes are positioned. Engagement prongs  64  and fender notch  65  are positioned so that hinge pins  16  pass through fender notch  65  and then enter the hinge pin holes in dorsal member  112 . 
         [0078]    Insert support element  60  is made from materials similar to the rest of the plastic speculum, for example polycarbonate, preferably transparent. 
         [0079]    Insert support element  60  is not glued, welded or otherwise permanently attached to any portion of speculum  10 . 
         [0080]    Insert support element  60  may be used in addition to strengthening speculum  10  as a smoke remover. Nipple  70  is hollow and may be pneumatically connected to a suction source via tube  71 , best seen in  FIGS. 6A and 6B  discussed below, so as to withdraw smoke and other residue resulting from electrosurgical or laser ablation gynecological procedures. 
         [0081]    Typically, insert support element  60 , including nipple  70 , may be formed as an integral element using injection molding. In some embodiments, insert support element  60  may have a threaded male proximal end onto which a complementary threaded hollow elongated female element, nipple  70 , may be screwed. 
         [0082]    In order to further enhance smoke removal, apertures  68  may be constructed in seat  62  of insert support element  10 . 
         [0083]    The contour of seat  62  is such that it effectively forms a channel with the interior surface, that is, the concave surface, of dorsal blade member  12  as seen in  FIG. 2  and discussed above. Smoke or debris resulting from an electrosurgical or laser ablation gynecological procedure may be drawn off by suction through such channel as shown in  FIGS. 2 and 6A . In  FIG. 6A , tube  71  is connected to a suction source; the source itself is not shown. 
         [0084]    Seat  62  of insert support element  60  may be flatter or more curved than that shown in  FIG. 4B . Both a flatter or more curved shape for insert support elements  60  permit effective channeling of smoke and/or detritus to nipple  70  and out of the speculum when a suction source is applied. 
         [0085]    In  FIG. 5 , in another embodiment of the present invention, insert support element  60  is shown constructed with a retainer ring  75  through which an electrical connection of a light source, typically a light emitting diode (LED), and/or optical equipment may be positioned. 
         [0086]    While not intended to be bound to a specific analysis of the forces involved, it is possible that the following analysis explains, at east partially, why the speculum of the present invention exhibits greater mechanical strength than conventional plastic specula and does not fracture at unacceptably low loads.  FIG. 6A  shows the forces believed to be acting on speculum  10  of the present invention. When inserted into the vagina during an examination, forces F T  act substantially perpendicular (vertical) to blades  12 ,  14  trying to return the blades from their open to their closed configuration. An upward force from the pins is generated and transferred via fenders  66  to the arcuate-shaped proximal region of seat  62 . This arcuate-shaped region of seat  62  is positioned adjacent to the arcuate proximal end of dorsal blade member  12  the latter forming together with lateral walls  61  of dorsal handle  26 , inspection aperture  63  as shown in  FIGS. 6A-6B . 
         [0087]    It is also believed that shear forces are better transferred and dispersed away from the hinge region by insert support element  60 .  FIG. 6B  is a Figure of the speculum of the present invention showing two axes AA′ and BB′. Axis BB′ is situated above the pin region while AA′ is positioned below the pin region.  FIG. 6C  show cross sectional views along these axes. Below the pin region (AA′), a shear force F S  operates only on an area xy as insert element  60  does not extend below the pin region. Above the pin region where the insert element is located, shear force Fs operates on an area xy+xz, the area provided by the dorsal member lateral wall  61  having a thickness y and the insert element having a thickness z. Therefore at AA′, shear=Fs/xy while at BB′, shear=Fs/(xy+xz). The shear at AA′ being less at BB′ indicates that the shear stress has been transferred, and fracture around and above the hinge region is less likely. 
         [0088]    It should be evident to one skilled in the art that while we have described speculum  10  of the present invention as having hinge pins  16  on the ventral member  114  and hinge holes on the dorsal member, the invention can be effected with a construction where the hinge pins are located on the dorsal member  112  and the hinge holes on the ventral member  114 . 
         [0089]    Plastic specula constructed according to the present invention have a destructive testing strength of at least about 6 kg, and therefore like metal specula they can be used in long duration gynecological procedures, including surgical procedures. Additionally, it is useful for gynecological out-patient procedures for which weaker specula are unsuited, such as colposcopy. 
         [0090]    Reference is now made to  FIGS. 7-12  in which another embodiment of a disposable speculum  100  and an insert support element  160  is shown.  FIG. 7  is a side view of speculum  100  in its open configuration while  FIGS. 8A-8C  show side, isometric, and proximal views of an insert support element  160  usable with speculum  100  in  FIG. 7 .  FIG. 8D  shows the relationship between the dorsal blade  192  and the seat  162  of insert support element  160 .  FIGS. 9A and 9B  show side and isometric views, respectively, of a lock element  196  used with speculum  100  shown in  FIG. 7 .  FIGS. 10A and 10B  present lock element  196  of  FIGS. 9A and 9B  positioned in speculum  100  of  FIG. 7 .  FIGS. 11A and 11B  show lock element  196  in its unlocked and locked position, respectively, while  FIG. 12  is a proximal view of speculum  100  of  FIG. 7 . 
         [0091]    Reference is now made to  FIG. 7 . Speculum  100  shown therein is formed of an injection molded plastic, in the present invention a high strength plastic, such as polycarbonate. Other resins or other materials possessing similar mechanical strength may also be used to form the specula of the present invention. In all cases, the plastic must be stronger and more durable than currently employed polystyrene or polypropylene. Typically, the plastic is a clear transparent plastic but colored or non-transparent high strength plastics may also be used 
         [0092]    Speculum  100  is formed of a dorsal member and a ventral member. The dorsal member contains a dorsal blade member  192  and a dorsal handle  126 , the latter typically integrally formed with blade member  192 . 
         [0093]    The ventral member includes a ventral blade member  194 , a ventral handle  124  typically integrally formed with blade member  194 , and a pair of hinge pins  116  (one being obscured), one hinge pin on each side of ventral blade member  194  near its proximal end  211  where it joins ventral handle  124 . Hinge pins  116  can also be formed as studs, trunnions and the like, and, typically, are integrally formed with the ventral member. 
         [0094]    Hinge pins  116  are insertable into hinge groves  117 , one hinge groove  117  formed on each of a pair of lateral wall elements  210 , thereby engaging dorsal and ventral members so that speculum  100  is ready for use. Lateral wall elements  210  connect between and are typically integrally formed with dorsal blade member  192  and dorsal handle  126 . Hinge pins  116  in hinge groove  117  form a hinge around which dorsal blade member  192  pivots when speculum  100  is brought from its closed to its open configuration or vice-versa. Closed and open configurations have the same meaning in this embodiment as they have in previously described embodiments. In the closed configuration, dorsal blade member  192  lies facing and substantially adjacent to ventral blade member  194  essentially as shown in  FIGS. 1B and 2 .  FIG. 7  represents the open configuration of speculum  100 . 
         [0095]    The inside surface of lateral wall elements  210  is the surface that partially defines the inspection aperture of the speculum used by a physician during examinations. The proximal arcuate surface of dorsal blade  192  defines the remainder of the inspection aperture. 
         [0096]    In  FIG. 7 , a seat  162  of an insert support element  160 , discussed in greater detail below in conjunction with  FIGS. 8A-8B , is shown by broken lines adjacent to dorsal blade element  192 . 
         [0097]    The front profile of blade members  192  and  194  of speculum  100  discussed in conjunction with  FIG. 7  is very similar to the profile presented in  FIG. 2  when the blade members are in their closed configuration. Seat  62  of insert support element  60  in  FIG. 2  is the equivalent of seat  162  of insert support element  160 , discussed below with reference to  FIGS. 8A-8C . As in  FIG. 2 , seat  162  and the concave side of dorsal blade member  192  shown in  FIG. 8D  form a channel through which smoke and other detritus produced during a gynecological procedure may be evacuated from speculum  100 . 
         [0098]      FIG. 12 , to which reference is now made, is a proximal view, i.e. back view, of the speculum shown in  FIG. 7 . 
         [0099]      FIGS. 8A-8C  are side, isometric and proximal views of insert support element  160  which is constructed to be positionable adjacent to the concave side of dorsal blade member  192  as in  FIG. 7 . The concave and convex sides of dorsal blade member  192  and ventral blade member  194  are substantially the same as shown in the profile view of blade members  12  and  14  that appear in  FIG. 2 .  FIG. 8D  shows the relationship of the concave side of dorsal blade member  192  and seat  162  of insert support element  160 . 
         [0100]    As shown in  FIGS. 8A-8C , insert support element  160  is substantially saddle-shaped with fenders  166  extending generally transversely from both sides of seat  162 . Protruding from the proximal portion of seat  162  is nipple  170 . At the end of fenders  166  are engagement flanges  171  that compressively engage with the arc-shaped surface formed at the junction of dorsal blade member  192  and lateral wall elements  210  of dorsal handle  126 . Additionally, flange elements  173  compressively engage with the arc-shaped surface at the junction of dorsal blade member  192  and lateral wall elements  210 . The arc-shaped surface discussed here is obscured by fenders  166  in  FIGS. 7 and 12 . 
         [0101]    In other embodiments, rather than compressively attaching insert support element  160  with the dorsal member, receiving holes may be formed near the arc-shaped region discussed above to receive flanges  171  and  173 , thereby effecting attachment. 
         [0102]    Insert support element  160  is made from materials similar to the rest of the plastic speculum, for example polycarbonate. As would be evident to one skilled in the art, when support element  160  is compressively attached to the arc-shaped surface described above, a resilient material, such as polycarbonate, would be required. 
         [0103]    In addition to strengthening speculum  100 , insert support element  160  may be used as a smoke remover. Nipple  170  is hollow and may be pneumatically connected to a suction source (not shown) via a tube (also not shown), so as to withdraw smoke and other residue resulting from electrosurgical or laser ablation gynecological procedures. 
         [0104]    Typically, insert support element  160 , including nipple  170 , may be formed as an integral element using injection molding. In some embodiments, insert support element  160  may have a threaded male proximal end onto which a complementary threaded hollow elongated female element, nipple  170 , may be screwed. 
         [0105]    In order to further enhance smoke removal, apertures  168  may be formed in seat  162  of insert support element  160 . 
         [0106]    The contour of seat  162  is such that it effectively forms a channel with the interior surface, that is, the concave surface, of dorsal blade member  192  as seen in  FIGS. 7 and 8D  discussed above. 
         [0107]    Seat  162  of insert support element  160  may be substantially flat as shown in  FIGS. 8A-8B  or more curved than that shown there. Both a flat or curved shape for seat  162  of insert support element  160  permit effective channeling of smoke and/or detritus to nipple  170  and out of the speculum when suction is applied. 
         [0108]    While locking mechanisms similar to those previously described with other embodiments may be used with the speculum in  FIG. 7 , another type of lock element may also be used. This lock element, its positioning in the speculum and its operation are shown in  FIGS. 9A-9B ,  10 A- 10 B and  11 A- 11 B respectively. 
         [0109]    Side and isometric views of lock element  196  are shown in  FIGS. 9A-9B , respectively, reference to which is now made. Lock element  196 , also herein denoted as trigger element  196 , is typically a unitary element with a wedge end  195 , a press end  197 , a pin structure  198  lying essentially transverse to the length of trigger element  196 , a positioning protrusion  199  lying between press end  197  and pin structure  198 , and a trigger leg  193 . Trigger leg  193  extends from the ventral side of the body of trigger element  196  opposite to the side on which pin structure  198  and positioning protrusion  199  are located. The body of trigger element  196  is substantially of uniform thickness except for wedge end  195  which is thicker. 
         [0110]    Without intending to be limiting, trigger element  196  is typically integrally molded from a plastic, such as nylon, polyethylene, polypropylene, acetal (polyoxymethylene) and polycarbonate. 
         [0111]      FIG. 10A  shows the positioning of trigger element  196  in an aperture  185  in dorsal handle  126 . Aperture  185  through which trigger element  196  extends is obscured in both  FIGS. 10A and 10B  but is shown in  FIGS. 11A and 11B . Aperture  185  is situated between pin structure  198  and positioning protrusion  199  when trigger element  196  is inserted therethrough. Pin structure  198  rides above a pair of substantially parallel positioning projections  182 , the latter protruding essentially transversally from dorsal handle  126  in the distal direction. Since wedge end  195  of trigger element  196  is thicker than the remainder of element  196 , when wedge end  195  is moved to its locked position it becomes wedged in between positioning projections  182 .  FIG. 1013  is a top view of the positioning of trigger element  196  between positioning projections  182  along axis AA′.  FIG. 10A  identifies the A-A′ axis. As shown in  FIG. 10B , wedged wedge end  195  causes a slight deviation of positioning projections  182  from their initial generally parallel configuration. 
         [0112]    In  FIGS. 10A and 10B  positioning projections  182  do not contain a ratchet mechanism. In other embodiments, projections  182  may contain a ratchet mechanism. 
         [0113]    Turning to  FIGS. 11A and 11B , to which reference is now made, the position of trigger element  196  is shown when blade members  192  and  194  and handles  124  and  126  are movable ( FIG. 11A ), i.e. when element  196  is in its unlocked position, and when the blade members and the handles are not movable ( FIG. 11B ), i.e. when element  196  is in its locked position. When handles  124  and  126  are movable with respect to each other, blade members  192  and  194  may be separated or brought close together by pivoting the blades around pin  116 . Additionally, the blade members may be separated from each other by moving handles  124  and  126  so that pins  116  move along ratchet track  175  ( FIG. 7 ). Thus, the present speculum  100  has two degrees of freedom, a rotation around pins  116  and a translation motion of pins  116  along track  175 . 
         [0114]    After speculum  100  is brought from its closed configuration, substantially the same configuration as in  FIG. 1B , to its partially or completely open configuration as in  FIG. 7 , trigger element  196  is used to lock handles  124  and  126  so that blade members  192  and  194  are in the fixed position selected by the physician for carrying out the required gynecological procedures. 
         [0115]    Locking of speculum  100  when the height of dorsal blade  192  vis-à-vis ventral blade  194  and/or the desired angle separating the blades has been reached, is effected by pushing press end  197  of trigger element  196  upward. Trigger element  196 , situated in aperture  185  in the lower portion of dorsal handle  126  rotates so that wedge end  195  moves downward as in  FIG. 11B  in between positioning projections  182 . Semi-flexible trigger leg  193  rests on the edge of ledge  181  of the lower portion  180  of dorsal handle  126 . This locks the dorsal  126  and ventral  124  handles and prevents further rotation and/or translation of blade members  192  and  194 . Trigger leg  193  acts as a spring pushing trigger element  196  up so that element  196  can move out of its locked position while retaining pin structure  198  as a rotational axis. 
         [0116]    To unlock, i.e. open, locked speculum  100 , the user pushes down on press end  197  of trigger element  196  causing wedge end  195  to rotate upward and out from between positioning projections  182 . 
         [0117]    It should readily be understood by one skilled in the art that an advantage of the present locking mechanism is that locking and unlocking of speculum  100  can be effected with one hand. This leaves the second hand free to perform other operations required by the gynecological procedures being executed. 
         [0118]    Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims. All publications, patents and patent applications mentioned in this specification are herein incorporated in their entirety by reference into the specification, to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated herein by reference. In addition, citation or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present invention. Therefore, it will be appreciated by persons skilled in the art that the present invention is not limited by what has been particularly shown and described herein above. Rather the scope of the invention is defined by the claims that follow.