Abstract:
A single use morcellator utilizes a disposable housing, cutting tube, battery and motor in combination with an attached and adjustable trocar to enable the surgeon to selectively utilize the cutting edge of the tube. The battery and control circuit are completely contained within the integral morcellator such that no separate components are needed.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to the field of surgery and more particularly to a surgical instrument to be used in gynecologic surgery and urological surgery and in other surgical fields. One of the most well-known procedures in the gynecology field are hysterectomies where the uterine body is removed. The advantages by doing the procedure laproscopicly are that the patient on needs two or 3 minor scar on the abdomen, and potentially has an easier recovery than when the abdominal muscle is cut in older forms of surgery. Once the uterus has been separated from the cervix the uterine tissue need to be removed from the patient throughout one of small incisions in the abdomen. Since the uterus has a diameter up to 300 mm or more a appropriate tool is need to render the uterus into pieces sized in a way that they can be removed throughout one of the small incisions. The tool to do this is called a Morcellator. The morcellator renders the tissue into small pieces or preferably long strips which can be drawn out through the central lumen of the morcellator. Most of the morcellators uses a principle where a rotating sharp tube cuts into the uterus while the surgeon pulls the tissue backwards using an appropriate forceps. 
     The common morcellator is built from following basic parts: 
     Cutting tube, which is a driven rotating tube operating from 200 to 1000 RPM depending on brand/model, and which can be made from stainless steel or mild steel. The wall thickness vary such that for reusable blades relatively thick wall blades are often seen while single use blades tend to be made from thin wall steel. 
     Drive Unit: 
     The drive unit can be located in hand-piece or in a separate “drive unit” placed on the table away from the hand-piece. The separate drive unit can have a built in motor turning the cutting tube via a gearbox or a motor may be connected the gearbox through a mechanical cable extending from a remote drive or it can be a power supply feeding the motor in the hand-piece with electrical power. 
     Gear Box: 
     The drive unit can be a separate unit from the drive unit and is typically intended to transfer the torque from the motor to the rotating cutting tube. 
     Control Mechanism. 
     Various mechanisms are known in the prior art with the most common being a foot pedal connected to the drive unit and acting as an on/of switch for the morcellator. A few powered morselators are hand controlled operated and do not have a foot pedal. 
     Hand Piece: 
     The prior art hand pieces for powered morselators range from bulky to heavy. 
     Charging Stands and Power Supplies: 
     Prior art morcellators have been powered by remote and encased power supplies that were either renewable or rechargeable. 
     Previous morsellators were cumbersome could not deliver adequate functional capabilities unless they were driven by an external or rechargeable power supply. For example one widely used morsellator uses a remote drive which was connected to the cutting tube through a cable which extended from the sterile operating field to a rotary drive. As noted above this device could be controlled by a foot control connected to the rotary drive. None of the known powered morsellators are unitary integrated devices which are designed to be disposed of after a single use. Some may have disposable components such as a cutting tube, however the remaining parts are all parts that must be tediously sterilized and cleaned after each use, thereby increasing the labor cost of the medical services. If any component accidentally leaves the sterile operating field, the procedure must be halted until a new sterile replacement for the component can be obtained from supply. Likewise, should a component such as a drive cable become tangled during the course of a procedure, the surgeon&#39;s control of the morsellator is compromised by the tension in the cable and the procedure must be stopped and restarted with a replacement part. It is noteworthy to mention that some surgeons consider the driven morsellator the most dangerous surgical instrument in use today. Consequently a need exists for a ready to use, disposable, single piece morsellator that will be smaller and more ergonomic than existing morsellators. 
     SUMMARY OF THE PRESENT INVENTION 
     It is an object of the present invention to provide a fully integrated, one piece, disposable morcellator to be used for the surgical gynecological and urological field. The fully disposable morcellator offers the surgeon several advantages including ease of use, no parts to be cleaned, and full control by the hand with high level of safety in combination with excellent maneuverability. 
     These and other objects and advantages of the invention will become apparent from the following detailed description of the preferred embodiment of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       An apparatus for tissue removal is depicted in the accompanying drawings which form a portion of this disclosure and wherein: 
         FIG. 1  is a perspective view of the integrated morsellator; 
         FIG. 2  is a side sectional view of the integrated morsellator; 
         FIG. 3  is a schematic diagram of the control circuit of the morsellator; and 
         FIG. 4  is a schematic diagram of another embodiment of the control circuit. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to the  FIGS. 1-4  for a clearer understanding of the invention, it may be seen that the preferred embodiment of the invention contemplates a fully disposable morcellator  11 . Morcellator  11  includes a tubular cutting tube  101  which extends from a pistol grip type plastic housing  124  and defines a lumen  102  there through. Housing  124  contains an alkaline battery package  112  powering an enclosed motor  113 . The motor  113  drives a toothed wheel or gear  114  which engages a second gear  103  formed on a radial extension  104  of a hub  106  as a part of the 90 degree gear  115  which rotates the cutting tube  101 . Hub  106  includes an elongated tubular portion  107  within which cutting tube  101  is received and secured and radial extension  104 . Cutting tube  101  is made from thin wall stainless steel or other acceptable metallic tube and is ground at the distal end to be as sharp as possible. Hub  106  is preferably made from plastic, thus the two parts are mechanically joined together with any suitable means such as fasteners or an adhesive that prevents any longitudinal or annular displacement between the two parts. Plastic includes any rigid polymer that will hold the cutting tube in place despite longitudinal forces applied to it during the surgery. It will be understood that any other suitable means of joining the cutting tube to the hub may be employed however, the tube must not be displaced longitudinally in the hub during use. The secured end of hub  106  is also fitted with a sealing device such as a duckbill housing  125  which is rigidly secured to housing  124 . The duckbill housing  125  avoids or minimizes gas leakage during the procedure. The duckbill house encompasses a duckbill seal  127  and a sealing disc  128 . The duckbill seal  127  stops gas leakage when no forceps or instrument are inserted through the lumen  102  of the morcellator and the disc  128  stops leakage when the forceps are inserted through the lumen  102 . 
     Hub  106  is rotatably mounted within housing  124  on a bearing  131  supported on gussets  132  such that the hub  106  and thus the cutting tube  101  are restrained from axial movement. A seal  133  prevents leakage about the hub  106  at bearing  131 . The opposite end of hub  106  is mounted for rotation on bearing  136  in flange  137  on duckbill housing  125  such that lumen  102  is in communication with the interior of duckbill housing  125 . 
     The morcellator  11  includes a built in trocar  122  which means that the morcellator in companion with the obturator  123  can be introduced through an incision without the necessity of a separate trocar. Trocar  122  is rotatably mounted to housing  124  such that by rotating trocar  122  it is movable axially along cutting tube  101  to cover more or less of the sharp distal end of the cutting tube  101 . Preferably, trocar  122  can be adjusted using integral knob  139  to at least three positions. In the SAFE position the trocar completely shields the cutting tube  101  and the morcellator is safe and ready to be introduced through the incision in the abdomen, Cut  1  exposes the cutting edge of cutting tube  101 , and Cut  2  retracts the trocar such that only an arc of the cutting edge is exposed. Preferentially, knob  139  is selectively turned to each position and is retentively held at that position by a detent and ball or other locking mechanism. In one embodiment, the trocar  122  and knob cooperate with a trigger guard  141  which is attached to housing  124  below a trigger switch  146  and extends outwardly to a free end  142  which engages slots in knob  139 . To rotate the trocar  122  the trigger guard end  142  is disengaged and then re-engaged in a selected slot  143 . The longitudinal movement of the trocar  122  is created by the interaction of the knob  139  with a cam surface such as a protusion  155  formed on housing  124  and engaged in a slot  156  in knob  139 . Various other camming combinations are contemplated. 
     As will be seen in  FIG. 1 , the distal end  152  of trocar  122  is beveled and angled such that one side of the end of the trocar forms an ellipse with the result that one side of the trocar is shorter than the other. As a result, one side of cutting tube  101  can be exposed without exposing the entire end of cutting tube  101 . This feature enables the longitudinal movement of trocar  122  to selectively expose the cutting tube  101 . The partial setting, or Cut  2  setting, is to be used when the surgeon wants to use the morcellator to engage the uterus at a selective area on the cutting tube. At the partial setting the sharp end of the cutting tube is partly shown. The Cut  1 , or full, setting fully exposes the cutting edge of the cutting tube and is used when the surgeon wants to core out strips of tissue. 
     The battery package  112  and motor  113  are electrically connected through a printed circuit board  117 . Trigger  146  is mechanically coupled connected to two switches  171  and  172  which should have be functionality equivalent to a B3S-1002P. Referring to  FIGS. 2 to 4 , the battery package  112  is preferably a 9V single use battery package including six 1.5V 2500 mAH batteries connected in series connected with a overload protecting fuse or diode  188  such as an S 175 . It will be appreciated that any suitable battery can be used. The battery package is wrapped in plastic (shrink tube) and fitted with 0.5 mm 2  leads. 
     The relays  161  and  162  on the PCB are miniature power PCB relays such as RY211009. The motor is connected to the battery through a normally open contact in each of the relays such that both relays have to be activated to close the contacts and power the motor. The other contacts in there relays are normally closed and cross connected such that when the trigger  146  is released and switches  171  and  172  are opened the two poles on the motor are short circuited through the relay contacts. By short circuiting the two motor poles the motor stops immediately when the trigger is released. Unloaded the motor has a speed of about 5800 RPM and after the gearing the rotating tube has a speed of about 650 RPM. 
     As seen in  FIG. 4  the voltage across the motor can be increased to give two speed operation using voltage booster  175 . A boost switch  176  can be separately actuated or can be incorporated as a second level of the depression of trigger  146 . 
     The apparatus as described and illustrated is intended for one use on one patient and is not intended to be sterilized or reused, thus, the cutting tube is not replaceable or interchangeable and the batteries are not replaceable or rechargeable. However, the design is sufficiently light weight and compact as to allow the surgeon to comfortably manipulate the instrument during the procedure without cumbersome cords or drive cables. It is to be understood that the form of the invention shown is a preferred embodiment thereof and that various changes and modifications may be made therein without departing from the spirit of the invention or scope as defined in the following claims.