Patent Description:
Anastomosis is the surgical joining of separate hollow organ sections. Typically, an anastomosis procedure follows surgery in which a diseased or defective section of hollow tissue is removed, and the end sections are stapled via a linear surgical stapler. Depending on the desired anastomosis procedure, the end sections may be joined by either circular, end-to-end, or side-to-side organ reconstruction methods.

In a circular anastomosis procedure, the two ends of the organ sections are joined by means of a stapling instrument which drives a circular array of staples through the end section of each organ section and simultaneously cores any tissue interior of the driven circular array of staples to free the tubular passage. Examples of instruments for performing circular anastomosis of hollow organs are described in <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; and <CIT>. Typically, these instruments include an elongated shaft having a handle portion at a proximal end to actuate the instrument and a staple holding component disposed at a distal end. After being positioned within tissue, an anvil assembly including an anvil rod with attached anvil head is mounted to the distal end of the instrument adjacent the staple holding component. A trocar of distal end of the instrument may include a band or other indicator which is designed to be covered or occluded by the anvil rod to help ensure proper alignment and engagement between the anvil rod and the trocar.

Opposed end portions of tissue of the hollow organ(s) to be stapled are clamped between the anvil head and the staple holding component. The clamped tissue is stapled by driving one or more staples from the staple holding component so that the ends of the staples pass through the tissue and are deformed by the anvil head. An annular knife is advanced to core tissue within the hollow organ to free a tubular passage within the organ. Generally, both the actuation of the staple forming mechanism and the advancement of the knife occur at the same time, i.e., simultaneously.

Besides anastomosis of hollow organs, surgical stapling devices for performing circular anastomosis have been used to treat internal hemorrhoids in the rectum. Typically, during use of a circular stapling device for hemorrhoid treatment, the anvil head and the staple holding component of the surgical stapling device are inserted through the anus and into the rectum with the anvil head and the staple holding component in an open or unapproximated position. Thereafter, a purse string suture is used to pull the internal hemorrhoidal tissue towards the anvil rod. Next, the anvil head and the staple holding component are approximated to clamp the hemorrhoid tissue between the anvil head and the staple holding component. The stapling device is fired to remove the hemorrhoidal tissue and staple the cut tissue.

<CIT> relates to a circular surgical stapler which provides an electrical contact sensor between the anvil and the trocar assembly to detect a coupling between both assemblies.

<CIT> relates to a surgical stapler with anvil seating detection.

The present invention is defined by the features of the independent claims.

The present disclosure relates to a trocar assembly for use with a circular stapler. The trocar assembly includes a shaft, a trocar tip, and a band. The trocar tip is configured to mechanically engage a distal portion of the shaft. The trocar tip includes a first portion and a second portion. The first portion is movable relative to the second portion prior to assembly of the trocar tip. The band encircles a part of the first portion of the trocar tip and a part of the second portion of the trocar tip.

In aspects, the first portion of the trocar tip may be movable relative to the second portion between a first position where the first portion and the second portion are free from contact with each other and a second position where the first portion and the second portion are in contact with each other. In aspects, the band may be configured to encircle the part of the first portion of the trocar tip and the part of the second portion of the trocar tip when the first portion and the second portion are in the second position. In further aspects, a distal end of the second portion of the trocar tip may extend farther distally than a proximal end of the first portion of the trocar tip when the first portion and the second portion are in the second position. In additional aspects, a distal most end of the trocar tip may be included on the first portion of the trocar tip.

In aspects, the first portion of the trocar tip may be configured to contact the shaft when the trocar tip is mechanically engaged with the shaft. In further aspects, the second portion of the trocar tip may be configured to contact the shaft when the trocar tip is mechanically engaged with the shaft.

In aspects, the band may be made from blends of polyphenylene oxides or polyphenylene ether resins with polystyrene, a liquid crystal polymer, or polyetheretherketone.

In aspects, the band may be a continuous ring.

The present disclosure also relates to a circular stapler having a handle assembly, an elongated body extending from the handle assembly, and a shell assembly. The shell assembly is disposed adjacent a distal end of the elongated body and includes a cartridge assembly and an anvil assembly. The cartridge assembly includes a trocar assembly. The anvil assembly includes a retention rod configured to selectively engage a portion of the trocar assembly. The trocar assembly includes a shaft, a trocar tip, and a band. The trocar tip is configured to mechanically engage a distal portion of the shaft. The trocar tip has a first portion and second portion. The first portion is movable relative to the second portion between a first position where the first portion and the second portion are free from contact with each other and a second position where the first portion and the second portion are in contact with each other. The band encircles a part of the first portion of the trocar tip and a part of the second portion of the trocar tip when the first portion and the second portion are in the second position. The band is occluded from view when the retention rod of the anvil assembly properly engages the portion of the trocar assembly.

In aspects, a distal end of the second portion of the trocar tip may extend farther distally than a proximal end of the first portion of the trocar tip when the first portion and the second portion are in the second position. In aspects, a distal most end of the trocar tip may be included on the first portion of the trocar tip.

In further aspects, the first portion of the trocar tip may be configured to contact the shaft when the trocar tip is mechanically engaged with the shaft. In aspects, the second portion of the trocar tip may be configured to contact the shaft when the trocar tip is mechanically engaged with the shaft.

The present disclosure also relates to a method of assembling a trocar assembly of a surgical instrument. The method includes sliding a band around a part of a first portion of a trocar tip such that the band encircles the part of the first portion, inserting a part of a second portion of the trocar tip between the band and the part of the first portion of the trocar tip, and securing the first portion of the trocar tip to the second portion of the trocar tip.

In aspects, securing the first portion of the trocar tip to the second portion of the trocar tip may occur after sliding the band around the part of the first portion of the trocar tip.

In aspects, securing the first portion of the trocar tip to the second portion of the trocar tip may include welding.

In further aspects, the method may include engaging the trocar tip with a shaft of the trocar assembly such that the first portion of the trocar tip and the second portion of the trocar tip contact the shaft.

Various aspects of the present disclosure are illustrated herein with reference to the accompanying drawings, wherein:.

Aspects of the presently disclosed surgical stapling instrument will now be described in detail with reference to the drawings wherein like numerals designate identical or corresponding elements in each of the several views. As is common in the art, the term "proximal" refers to that part or component closer to the user or operator, i.e. surgeon or physician, while the term "distal" refers to that part or component farther away from the user.

<FIG> illustrates an aspect of a surgical stapling instrument according to the present disclosure, referenced generally as circular stapler <NUM>. Circular stapler <NUM> includes a handle assembly <NUM>, an elongated body portion <NUM> extending distally from handle assembly <NUM>, and a shell assembly <NUM> mounted adjacent a distal end of elongated body portion <NUM>. The shell assembly <NUM> includes a cartridge assembly <NUM> and an anvil assembly <NUM>.

The handle assembly <NUM> shown in <FIG> is a power-operated handle including a first actuator <NUM>, a second actuator <NUM>, and a third actuator <NUM>. While the first actuator <NUM>, the second actuator <NUM>, and the third actuator <NUM> can be configured to perform at least one function, it is disclosed that the first actuator <NUM> causes the anvil assembly <NUM> to move proximally relative to the cartridge assembly <NUM>, the second actuator <NUM> causes the anvil assembly <NUM> to move distally relative to the cartridge assembly <NUM>, and the third actuator <NUM> causes fasteners to be ejected from the cartridge assembly <NUM> toward the anvil assembly <NUM>.

It is envisioned that the shell assembly <NUM> may be used with any actuation assembly, powered or manual, and capable of two independent actuation strokes, for example. Commonly owned <CIT>, discloses a surgical device having a powered actuator assembly including first and second drive members. In addition, it is envisioned that the independent actuation strokes may be completed by the same drive member completing two strokes or by two separate drive members.

It is contemplated that the shell assembly <NUM> according to the present disclosure can be part of a surgical system. The surgical system can include surgical end effector assemblies (such as shell assembly <NUM>) in various configurations. The elongated body portion <NUM> of the instrument may itself be a removable and replaceable part of the system. The handle assembly <NUM> can be manual, powered, or part of a robotic surgical system.

With reference to <FIG>, the shell assembly <NUM> includes the cartridge assembly <NUM> and the anvil assembly <NUM>. In disclosed aspects, the cartridge assembly <NUM> is removably secured to and/or within a distal end of the elongated body portion <NUM> such that the cartridge assembly <NUM>, or a portion thereof, may be replaced and circular stapler <NUM> may be reused. In other aspects, only a portion of the cartridge assembly <NUM> is configured to be removed, and subsequently replaced or reloaded. Alternatively, the circular stapler <NUM> may be configured for a single use, i.e., disposable.

With reference to <FIG>, the cartridge assembly <NUM> includes a housing <NUM>, a staple cartridge <NUM>, a knife assembly <NUM>, and a trocar assembly <NUM>. The anvil assembly <NUM> includes an anvil head <NUM> and a retention rod <NUM>. The anvil head <NUM> includes a plurality of staple-forming pockets which are configured to deform fasteners ejected from the staple cartridge <NUM> of the cartridge assembly <NUM>. The retention rod <NUM> extends proximally from the anvil head <NUM> and is configured to releasably engage the trocar assembly <NUM> of the cartridge assembly <NUM>.

With continued reference to <FIG>, the trocar assembly <NUM> includes a shaft <NUM>, a trocar tip <NUM> extending distally from the shaft <NUM> and configured to releasably engage the retention rod <NUM> of the anvil assembly <NUM>, and a band <NUM> disposed between the shaft <NUM> and the trocar tip <NUM>. In use, when the retention rod <NUM> of the anvil assembly <NUM> and the trocar tip <NUM> of the trocar assembly <NUM> are properly engaged (<FIG>), a portion of the retention rod <NUM> covers or occludes the band <NUM> which provides a visual indication to the user that the cartridge assembly <NUM> and the anvil assembly <NUM> are properly engaged.

In other instruments which utilize a similar type of band, the band is added to the trocar assembly <NUM> either as a coating and/or during a secondary process. Accordingly, the band of such instruments must be made of a limited type of material and may not be as robust as the rest of the trocar assembly, for instance.

Referring to <FIG>, the trocar assembly <NUM> of the present disclosure includes the band <NUM> that can be assembled along with the shaft <NUM> and the trocar tip <NUM> (as opposed to after assembly of the shaft <NUM> and the trocar tip <NUM>), thereby allowing the band <NUM> to be made of materials such as an engineering plastic consisting of amorphous blends of polyphenylene oxides ("PPO") or polyphenylene ether ("PPE") resins with polystyrene (e.g., NORYL®<NUM>), a liquid crystal polymer (e.g., VECTRA®<NUM>), or polyetheretherketone ("PEEK"), for instance. Further, since the band <NUM> is assembled along with the shaft <NUM> and the trocar tip <NUM>, the band <NUM> is able to be a unitary ring. In previous instruments utilizing a band, a unitary ring band would be challenging to use at least because the diameter of the band is smaller than the diameter of the distally-adjacent portion of the trocar tip, and is also smaller than the proximally-adjacent portion of the shaft. <NUM> Noryl is a registered trademark of SABIC Innovative Plastics IP B. <NUM> Vectra is a registered trademark of Ticona.

With particular reference to <FIG>, to enable the band <NUM> to be assembled along with the shaft <NUM> and the trocar tip <NUM> of the trocar assembly, the trocar tip <NUM> includes two separate portions: a first portion 220a and a second portion 220b. The first portion 220a of the trocar tip <NUM> includes an elongated distal portion 222a, a collar 224a, and a proximal portion 230a. The second portion 220b of the trocar tip <NUM> includes a body portion 222b, and a finger 224b extending distally from the body portion 222b and configured to engage the collar 224a of the first portion 220a of the trocar tip <NUM>.

More specifically, the proximal portion 230a of the first portion 220a of the trocar tip <NUM> includes a first ramp 232a, a second ramp (opposite the first ramp 232a and hidden from view in <FIG>), and a lateral extension 234a. The body 222b of second portion 220b of the trocar tip <NUM> includes a first ramp (hidden from view in <FIG>), a second ramp 226b, and a lateral extension 228b. The first ramp 232a of the first portion 220a is configured to engage the first ramp of the second portion 220b. The second ramp of the first portion 220a is configured to engage the second ramp 226b of the second portion 220b. Both the lateral extension 234a of the first portion 220a and the lateral extension 228b of the second portion 220b are configured to engage a distal end <NUM> of the shaft <NUM>.

Various steps of assembly of the trocar assembly <NUM> are shown in <FIG>. Initially, as shown in <FIG>, the band <NUM> is moved distally in the general direction of arrow "A" relative to the first portion 220a of the trocar tip <NUM>. The band <NUM> is moved distally past the proximal portion 230a of the first portion 220a of the trocar tip <NUM>, and is positioned such that the band <NUM> radially surrounds the collar 224a of the first portion 220a, as shown in <FIG>. Next, with continued reference to <FIG>, the second portion 220b of the trocar tip <NUM> is moved distally in the general direction of arrow "B" relative to the first portion 220a of the trocar tip <NUM> and relative to the band <NUM>. During this distal movement of the second portion 220b, the finger 224b of the second portion 220b is inserted between the band <NUM> and the collar 224a (occluded from view in <FIG>) of the first portion 220a of the trocar tip <NUM>. As shown in <FIG>, when the first portion 220a and the second portion 220b of the trocar tip <NUM> are engaged, the band <NUM> encircles the collar 224a of the first portion 220a and the distal finger 224b of the second portion 220b. The first portion 220a and the second portion 220b of the trocar tip <NUM> may then be welded together or otherwise secured.

As shown in <FIG>, the shaft <NUM> of the trocar assembly <NUM> is then moved distally in the general direction of arrow "C" relative to the trocar tip <NUM> such that the distal end <NUM> of the shaft <NUM> engages (e.g., via snap-fit connection) both the first portion 220a of the trocar tip <NUM> (at the lateral extension 234a) and the second portion 220b of the trocar tip <NUM> (at the lateral extension 228b). <FIG> illustrates the shaft <NUM> of the trocar assembly <NUM> engaged with the trocar tip <NUM> of the trocar assembly <NUM>.

<FIG> illustrate a trocar assembly <NUM> (or portions thereof) in accordance with a second aspect of the present disclosure. Trocar assembly <NUM> is configured for use with the shell assembly <NUM> of the circular stapler <NUM> in place of the trocar assembly <NUM> of <FIG>, for instance. For clarity, some common features between the trocar assembly <NUM> and the trocar assembly <NUM> will not be discussed in detail.

The trocar assembly <NUM> includes a shaft <NUM>, a trocar tip <NUM>, and a band <NUM>. With particular reference to <FIG>, to enable the band <NUM> to be assembled along with the shaft <NUM> and the trocar tip <NUM> (as opposed to after the shaft and trocar tip are assembly), the trocar tip <NUM> includes two separate portions: a first portion 2200a and a second portion 2200b. As shown in <FIG>, the first portion 2200a of the trocar tip <NUM> includes an elongated distal portion 2220a, a collar 2240a, and a notch 2260a. The notch 2260a extends longitudinally through the collar 2240a and through part of the elongated distal portion 2220a.

As shown in <FIG>, the second portion 2200b of the trocar tip <NUM> includes a body portion 2220b, a finger 2230b extending distally from the body portion 2220b, a first lateral extension 2240b extending proximally from the body portion 2220b, and a second lateral extension 2250b extending proximally from the body portion 2220b. The finger 2230b includes an elongated distal portion 2232b and a collar portion 2234b.

Various steps of assembly of the trocar assembly <NUM> are shown in <FIG>. Initially, as shown in <FIG>, the band <NUM> is moved proximally in the general direction of arrow "D" relative to the second portion 2200b of the trocar tip <NUM>. The band <NUM> is moved proximally past the elongated distal portion 2232b of the finger 2230b of the second portion 2200b of the trocar tip <NUM>, and is positioned such that the band <NUM> radially surrounds the collar portion 2234b of the finger 2230b, as shown in <FIG>. Next, with continued reference to <FIG>, the first portion 2200a of the trocar tip <NUM> is moved proximally in the general direction of arrow "E" relative to the second portion 2200b of the trocar tip <NUM> and relative to the band <NUM>. During this proximal movement of the first portion 2200a, the collar 2240a of the first portion 2200a is inserted between the band <NUM> and the collar portion 2234b of the second portion 2200b of the trocar tip <NUM>. Additionally, during this proximal movement of the first portion 2200a, the finger 2230b of the second portion 2200b engages with the notch 2260a of the first portion 2200a. The first portion 2200a and the second portion 2200b of the trocar tip <NUM> may then be welded together or otherwise secured.

As shown in <FIG>, when the first portion 2200a and the second portion 2200b of the trocar tip <NUM> are engaged, the band <NUM> encircles the collar 2240a of the first portion 2200a and the collar portion 2234b of the second portion 2200b.

With continued reference to <FIG>, the trocar assembly <NUM> is then moved proximally in the general direction of arrow "F" relative to the shaft <NUM> such that a distal end <NUM> of the shaft <NUM> engages (e.g., via snap-fit connection) the first lateral extension 2240b and the second lateral extension 2250b of the second portion 2200b of the trocar tip <NUM>; the shaft <NUM> does not contact the first portion 2200a of the trocar tip <NUM>. <FIG> illustrates the shaft <NUM> of the trocar assembly <NUM> engaged with the trocar tip <NUM> of the trocar assembly <NUM>.

Claim 1:
A trocar assembly (<NUM>) for use with a circular stapler, the trocar assembly comprising:
a shaft (<NUM>);
a trocar tip (<NUM>) configured to mechanically engage a distal portion of the shaft, the trocar tip including a first portion (220a) and second portion (220b), the first portion is movable relative to the second portion prior to assembly of the trocar tip; and
a band (<NUM>) encircling a part of the first portion of the trocar tip and a part of the second portion of the trocar tip characterised in that both the first portion (220a) and the second portion (220b) of the trocar tip are configured to contact the shaft (<NUM>) when the trocar tip is mechanically engaged with the shaft.