Patent Publication Number: US-2021169487-A1

Title: Surgical stapling instruments

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of and priority to U.S. Provisional Patent Application No. 62/944,548, filed Dec. 6, 2019, the entire disclosure of which is incorporated by reference herein. 
    
    
     BACKGROUND 
     1. Technical Field 
     The present disclosure is directed to surgical instruments, such as surgical stapling instruments. In particular, the present disclosure relates to hand-held, battery-operated circular stapling instruments. 
     2. Background of Related Art 
     Circular stapling instruments are used to perform end-to-end anastomosis procedures within a patient. During an end-to-end anastomosis procedure, an end of a first vessel portion is joined to an end of a second vessel portion. Typically, circular stapling instruments include an anvil, which defines an annular array of staple deforming depressions, and an annular cartridge housing annular rows of staples. During actuation of the circular stapling instrument, the anvil is approximated toward the annular cartridge to clamp tissue therebetween. When it is determined that the tissue has been clamped between the anvil and the annular cartridge, staples may then be ejected into the clamped tissue. 
     SUMMARY 
     In one aspect of the present disclosure, a surgical stapling instrument is provided. The surgical stapling instrument includes an elongated handle housing, a screw disposed within the handle housing, a rotatable knob supported by the handle housing, an elongated body portion extending distally from the handle housing, and an end effector. The knob is coupled to a proximal end portion of the screw, such that a rotation of the knob results in motion of the screw. The end effector includes a cartridge assembly coupled to a distal end portion of the elongate body portion, and an anvil assembly coupled to a distal end portion of the screw. The anvil assembly is configured to translate relative to the cartridge assembly in response to a manual rotation of the knob to move the end effector between unapproximated and approximated positions. 
     In some aspects, the knob may extend proximally from a proximal end portion of the handle housing. 
     In some aspects, the knob, the screw, and a proximal end portion of the elongated body portion may be coaxial. 
     In some aspects, the screw may be configured to translate within the handle housing in response to a rotation of the knob. 
     In some aspects, the surgical stapling instrument may further include a sensor configured to determine a relative axial position of the screw. 
     In some aspects, the screw may have a flag extending outwardly therefrom. The flag may be disposed adjacent the sensor, such that the sensor is configured to determine a relative axial position of the flag. 
     In some aspects, the surgical stapling instrument may further include a fire switch and a light disposed adjacent the fire switch. The fire switch may be coupled to the handle housing and in communication with a motor. The sensor may be configured to turn on the light upon determining that the screw is in an axial position corresponding to the approximated position of the end effector. 
     In some aspects, the surgical stapling instrument may further include an instrument module insertable into a cavity defined by the handle housing. The instrument module may include a housing, a motor disposed within the housing, and an output gear drivingly coupled to the motor. 
     In some aspects, the surgical stapling instrument may further include a nut gear operably coupled to the output gear, and a fire shaft having a proximal end portion and a distal end portion. The proximal end portion of the fire shaft may be operably coupled to the nut gear, and the distal end portion of the fire shaft may be coupled to a pusher of the cartridge assembly. The fire shaft may be configured to translate the pusher in response to a rotation of the nut gear. 
     In some aspects, the nut gear may have a plurality of gear teeth disposed about an outer periphery thereof. The nut gear may further include a threaded inner surface threadedly engaged to the proximal end portion of the fire shaft. 
     In some aspects, the screw may extend longitudinally through the fire shaft and the nut gear. 
     In some aspects, the surgical stapling instrument may further include a fire gear intercoupling the output gear and the nut gear. 
     In accordance with another aspect of the present disclosure, a handle assembly of a circular stapler is provided. The handle assembly includes an elongated handle housing, a drive shaft disposed within the handle housing, and a rotatable knob supported by the handle housing. The drive shaft has a distal end portion configured to effect an opening and closing of an end effector. The knob is coupled to a proximal end portion of the drive shaft, such that a rotation of the knob results in axial motion of the drive shaft. 
     In some aspects, the knob may extend proximally from a proximal end portion of the handle housing. 
     In some aspects, the drive shaft may be a screw disposed within a bottom end portion of the handle housing. 
     In some aspects, the handle assembly may further include a sensor disposed in the handle housing. The drive shaft may have a flag extending outwardly therefrom. The flag may be disposed adjacent the sensor, such that the sensor is configured to determine a relative axial position of the flag. 
     In some aspects, the handle assembly may further include a fire switch and a light disposed adjacent the fire switch. The fire switch may be coupled to the handle housing and in communication with a motor. The sensor may be configured to turn on the light upon determining that the drive shaft is in an axial position corresponding to an approximated position of the end effector. 
     In some aspects, the handle assembly may further include an instrument module insertable into a cavity defined by the handle housing. 
     In some aspects, the handle assembly may further include a nut gear operably coupled to the output gear, and a fire shaft. The fire shaft may have a proximal end portion operably coupled to the nut gear, and a distal end portion configured to effect a stapling function of the end effector. 
     In some aspects, the drive shaft may extend longitudinally through the fire shaft and the nut gear. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments of the presently disclosed surgical stapling instruments are disclosed herein, with reference to the following drawings: 
         FIG. 1  is a perspective view of a surgical stapling instrument including a handle assembly, an elongated body portion, and an end effector; 
         FIG. 2  is a perspective view, with a housing half of a handle housing removed, illustrating the surgical stapling instrument of  FIG. 1  with an instrument module separated from the handle housing; 
         FIG. 3  is a side view of the surgical stapling instrument of  FIG. 2  illustrating internal components of the handle assembly; 
         FIG. 4  is a longitudinal cross-sectional view of the surgical stapling instrument of  FIG. 2 , as taken through  4 - 4  of  FIG. 2 ; 
         FIG. 5  is an enlarged, perspective view of the surgical stapling instrument, with the housing half removed, illustrating the internal components of the handle assembly; 
         FIG. 6  is an enlarged, perspective view, illustrating a fire switch and illumination lights of the handle assembly; 
         FIG. 7  is an enlarged view of the area of detail labeled “7” in  FIG. 4 ; and 
         FIG. 8  is an enlarged, perspective view, illustrating the instrument module of  FIG. 2  being connected to a printed circuit board of the handle assembly. 
     
    
    
     DETAILED DESCRIPTION 
     Persons having skill in the art will understand the present disclosure from reading the following description in conjunction with the accompanying drawings. Reference characters indicate the same or similar elements throughout the drawings. As is customary, the term “distal” refers to a location farther from the user of the instrument and the term “proximal” refers to a location that is closer to the user of the instrument. 
       FIGS. 1 and 2  illustrate an embodiment of a surgical stapling instrument according to the present disclosure, referenced generally as a circular stapler  10 . Circular stapler  10  includes a handle assembly  12 , an elongated body portion  14 , which is supported by and extends distally from the handle assembly  12 , and an end effector  16  coupled to a distal end portion  14   b  of the elongated body portion  14 . The handle assembly  12  includes an instrument or power module  18  insertable into a handle housing  20  of the handle assembly  12 . The instrument module  18  is reusable, whereas the remainder of the circular stapler  10  (e.g., the handle housing  20 , the elongated body portion  14 , and the end effector  16 ) may be disposable. In aspects, the entire circular stapler  10  may be reusable or disposable. 
     With reference to  FIGS. 1-4 , the end effector  16  is supported on the distal end portion  14   b  of the elongated body portion  14  or otherwise coupled to the distal end portion  14   b  of the elongated body portion  14 . In some embodiments, the end effector  16  may be monolithically formed with or integrally connected to the distal end portion  14   b  of the elongated body portion  14 . The end effector  16  includes a cartridge assembly  28  and an anvil assembly  30 . The cartridge assembly  28  includes a staple cartridge  32  configured for supporting a plurality of surgical staples (not shown) therein and to discharge the staples into tissue after approximation of the cartridge assembly  28  and the anvil assembly  30 . The staple cartridge  32  accommodates an annular pusher  34  ( FIG. 4 ) for advancing the staples through the staple cartridge  32 . The staple cartridge  32  defines a longitudinal channel  36  for movable receipt of a trocar  38  ( FIG. 4 ) of the anvil assembly  30 . The staple cartridge  32  has a plurality of annular rows of staple retaining recesses having the surgical staples disposed therein. 
     The anvil assembly  30  includes, inter alia, the trocar  38 , an anvil head  40 , and an anvil center rod  42  extending from the anvil head  40 . The trocar  38  extends through and from the elongated body portion  14  and is movably disposed within the channel  36  of the cartridge assembly  28 . The trocar  38  is configured to detachably (or in some aspects permanently) receive the anvil center rod  42  therein. A proximal end of the trocar  38  is configured to be removably or non-removably coupled to a central shaft  44  that extends longitudinally through the elongated body portion  14 . The central shaft  44  is operable to selectively longitudinally move the trocar  38  to move the anvil head  40  between unapproximated and approximated positions, in relation to the cartridge assembly  28 , in response to actuation of the handle assembly  12 , to clamp tissue between the cartridge and anvil assemblies  28 ,  30 , as will be described in further detail below. 
     Reference may be made to U.S. Pat. No. 7,802,712 for a detailed description of the construction and operation of an end effector including a cartridge assembly and an anvil assembly similar to that disclosed herein, the entire contents of which being incorporated by reference herein. 
     With continued reference to  FIGS. 1-4 , the handle assembly  12  of the circular stapler  10  includes the handle housing  20 , a door  50 , and a clamping actuation assembly  52  for translating the central shaft  44  along with the attached anvil assembly  30 . The handle housing  20  has an elongated configuration, and in some aspects, a generally rectangular configuration, and defines an elongated cavity  54  therein dimensioned for receipt of various components of the circular stapler  10 . The cavity  54  has an upper end portion or half  54   a  for accommodating the instrument module  18 , and a bottom end portion or half  54   b  separated from the upper end portion  54   a  by a partition  56 . The handle housing  20  has a proximal end portion  20   a  defining an opening  58  dimensioned for removable receipt of the instrument module  18 . The door  50  is hingedly coupled to the proximal end portion  20   a  of the handle housing  20  and configured to pivot between an opened position ( FIG. 2 ), in which the proximal opening  58  of the handle housing  20  is exposed, and a closed position ( FIG. 1 ), in which the door  50  covers the proximal opening  58  to enclose the instrument module  18  in the cavity  54 . 
     The clamping actuation mechanism  52  of the handle assembly  12  includes a drive shaft  60  and a rotatable knob  62  coupled to the drive shaft  60 . The drive shaft  60  may be a screw and extends through the bottom end portion  54   b  of the cavity  54  and in coaxial alignment with a longitudinal axis “X” defined by the elongated body portion  14 . The screw  60  has a threaded proximal end portion  60   a  disposed in the proximal end portion  20   a  of the handle housing  20 , and a distal end portion  60   b  disposed in a distal end portion  20   b  of the handle housing  20 . The distal end portion  60   b  of the screw  60  is fixed to a proximal end portion  47  of the central shaft  44 , such that the screw  60  and the central shaft  44  move longitudinally with one another. 
     The knob  62  of the clamping actuation mechanism  52  is coupled to the proximal end portion  60   a  of the screw  60 . In aspects, an elongated collar  64  is provided and is rotationally supported in the proximal end portion  20   a  of the handle housing  20  and threadedly coupled to the threaded proximal end portion  60   a  of the screw  60 . The knob  62  is fixed about the elongated collar  64  and protrudes proximally from the proximal end portion  20   a  of the handle housing  20 . As such, a manual rotation of the knob  62  drives a translation of the screw  60  via the threaded engagement of the elongated collar  64  and the screw  60 . In aspects, the knob  62  may be directly threadedly coupled to the screw  60 . The knob  62  allows for the deliberate and precise clamping of tissue by the clinician. In some aspects, instead of using the manually-rotatable knob  62  for closing the end effector  16 , a motor (not shown) may be provided to effect a closing of the end effector  16 . 
     With reference to  FIGS. 5 and 6 , the handle assembly  12  includes an anvil position sensor  66 , such as, for example, an optical sensor, for determining when the end effector  16  is in a clamped state and ready for firing. The screw  60  of the clamping actuation mechanism  52  has a flag or tab  68  extending radially outward therefrom. The flag  68  is disposed in side-by-side relation with the sensor  66  and moves with the screw  60  as the screw  60  effects an opening or closing of the end effector  16 . The sensor  66  is configured to determine a relative axial position of the flag  68  of the screw  62  throughout the translation of the screw  60 . 
     The sensor  66  may be supported on a first printed circuit board  70  of the handle assembly  12  and in electrical communication with one or more lights  72 , such as, for example, LEDs, disposed adjacent a fire button  74 . In aspects, the sensor  66  may be in wireless communication with a second printed circuit board  88 , which is powered by the instrument module  18 . The first or second printed circuit board  70  or  88  may have a processor  76  and a memory for storing instructions. The processor  76  is in electrical communication with the sensor  66  by wires, leads, or via wireless connection. The processor  76  is configured to send a signal to the lights  72  to turn on when the sensor  66  determines that the flag  68  of the screw  60  is disposed at a proximal-most position corresponding to an approximated/clamped state of the end effector  16 . The lights  72  may be disposed underneath the fire button  74  to illuminate the fire button  74 , thereby indicating to a clinician that the circular stapler  10  is ready for firing. 
     The processor  76  may be a controller, such as, for example, a microcontroller. The processor  76  may be an integrated circuit, analog or logic circuitry, and/or microprocessor, or an array of such components. The processor  76  receives information from the memory. In one embodiment, the memory may be an erasable programmable read only memory (“EPROM”). 
     With reference to  FIGS. 2, 5, 7, and 8 , the instrument module  18  includes a housing  78 , a motor  80  and battery (not explicitly shown) stored in the housing  78 , and an output gear  82  drivingly coupled to the motor  80  and extending distally from the housing  78 . In aspects, the instrument module  18  may be equipped with the processor  76  and various other electronics. The instrument module  18  is insertable into the cavity  54  of the handle housing  20  and is configured to operably couple to a fire shaft  108  provided in the handle housing  20 . The instrument module  18  has a card edge power module connector  84  configured to selectively engage a card edge connector  86  of the second printed circuit board  88  in the handle housing  20  upon inserting the instrument module  18  into the handle housing  20  to electromechanically connect the fire button  74  with the motor  80  of the instrument module  18 . The battery of the instrument module  18  is configured to provide power to the lights  72  via the second printed circuit board  88 . In aspects, the instrument module  18  may be disposable and permanently integrated into the handle housing  20  rather than being removable and reusable. 
     With reference to  FIGS. 2-5, 7, and 8 , the handle assembly  12  includes a staple fire actuation assembly  100  configured to electromechanically fire staples from the cartridge assembly  28 . The staple fire actuation assembly  100  includes a hub  102  fixed within the distal end portion  20   b  of the handle housing  20 , a fire gear  104 , a nut gear  106 , and a fire shaft  108 . The hub  102  has an upper portion including a left housing  102   a  configured to receive the output gear  82  of the instrument module  18 , and a right housing  102   b  for supporting the fire gear  104  therein. The hub  102  further includes a collar  102   c  extending downwardly from the right housing  102   b  and disposed about the nut gear  106  to resist axial translation of the nut gear  106 . 
     The fire gear  104  is rotationally supported in the right housing  102   b  of the hub  102  and is configured to operably engage the teeth of the output gear  82  of the instrument module  18 , such that a rotation of the output gear  82  drives a rotation of the fire gear  104 . The fire gear  104  is disposed about an axle  112  that is rotationally supported by the hub  102 . The fire gear  104  may be retained in the right housing  102   b  by a stopper or plug  114  attached to a distal end of the axle  112 . 
     The nut gear  106  is disposed in the lower end portion  54   b  of the cavity  54  and is disposed about the screw  60 . The nut gear  106  has a plurality of gear teeth  116  disposed around an outer periphery of the nut gear  106 . The gear teeth  116  of the nut gear  106  are in meshing engagement with the fire gear  104 , and a threaded inner surface  118  of the nut gear  106  is threadingly engaged with a threaded outer surface of a proximal end portion  108   a  of the fire shaft  108 . The fire shaft  108  is disposed about the distal end portion  60   b  of the screw  60  and is free to translate relative to the screw  60 . The fire shaft  108  has a distal end portion  108   b  fixed to the pusher  34  ( FIG. 4 ) of the cartridge assembly  28  and is configured to distally translate the pusher  34  in response to an actuation of the motor  80  of the instrument module  18 . 
     The fire staple actuation mechanism  100  further includes a fire switch  110  in electrical communication with the instrument module  18  via the second printed circuit board  88 . The fire switch  110  is disposed between the fire button  74  and the right housing  102   b  of the hub  102 . As such, an actuation of the fire button  74  activates the motor  80  of the instrument module  18  when the instrument module  18  is connected to the second printed circuit board  88 . 
     To assemble the handle assembly  12 , the door  50  may be unlocked from the handle housing  20  and pivoted to an open position, as shown in  FIG. 2 . The instrument module  18 , which may not be sterile, is inserted into the cavity  54  of the handle housing  20  via the proximal opening  58 . Upon inserting the instrument module  18  into the handle housing  20 , the card edge power module connector  84  of the instrument module  18  engages the card edge connector  86  of the second printed circuit board  88 . 
     In use, two anatomical lumens, such as, for example, a colon, esophagus, and/or a stomach, may be disposed between the anvil plate  40  of the anvil assembly  30  and the cartridge assembly  28 . With the tissue in position, a clinician manually rotates the knob  62  of the clamping actuation mechanism  52 , whereby the elongated collar  64  rotates about its longitudinal axis relative to the screw  60 . Due to the threaded engagement of the elongated collar  64  with the screw  60 , the screw  60  translates proximally to longitudinally pull the central shaft  44  and the attached trocar  38  of the anvil assembly  30 . The anvil shaft  42 , which is fixed to the trocar  38 , is also moved proximally along with the attached anvil head  40  from the unapproximated position to the approximated position in relation to the cartridge assembly  28 . 
     As the screw  60  is translated, the flag  68  of the screw  60  moves relative to the sensor  66 , which continuously detects the relative axial position of the flag  68 . Rotation of the knob  62  is continued until the tissue is fully clamped by the end effector  16 . In particular, upon the flag  68  of the screw  60  moving to a predetermined axial position relative to the sensor  66 , the processor  76  activates the lights  72  of the handle assembly  12  to illuminate the fire button  74 . In some aspects, the processor  76  may be disposed in the instrument module  18 . With the fire button  74  illuminated, the clinician is made aware that the circular stapler  10  is ready to be fired. 
     An actuation of the fire button  74  causes the fire switch  110  to activate the motor  80  of the instrument module  18 . Upon activating the motor  80 , the output gear  82  of the instrument module  18  rotates, which drives a concomitant rotation of the fire gear  104 . Due to the fire gear  104  being operably engaged with the nut gear  106 , the rotation of the fire gear  104  rotates the nut gear  106 , thereby driving a distal translation of the fire shaft  108  relative to the nut gear  106 . The distal translation of the fire shaft  108  translates the pusher  34  distally to push staples from the cartridge assembly  28  into the clamped tissue. 
     While the present disclosure has been described and illustrated in connection with certain embodiments, it is not the intention of the applicant to restrict or in any other way limit the scope of the claims to such detail. Additional advantages and modifications will be readily apparent to those skilled in the art.