Flexible cannula having selective rigidity

A surgical access device includes a housing having a tubular member extending therefrom. The tubular member has inner and outer walls defining an annular lumen therebetween. A passageway extends between proximal and distal openings of the tubular member. The passageway is configured to receive a surgical instrument therethrough. A conduit is disposed in the annular lumen and includes spiral segments where each spiral segment is engaged with an adjacent spiral segment. The conduit is flexible in a first state and is fixed in a second state. A valve assembly is coupled to the housing and includes a port that is in fluid communication with the annular lumen. The port is attachable to a source of fluid.

FIELD

The present disclosure generally relates to surgical instruments for minimally invasive surgery. In particular, the present disclosure relates to a flexible cannula having selective rigidity.

BACKGROUND

A minimally invasive surgical procedure is one in which a surgeon enters a patient's body through one or more small openings in the patient's skin or naturally occurring openings (e.g., mouth, anus, or vagina). As compared with traditional open surgeries, minimally invasive surgical procedures have several advantages and disadvantages. Minimally invasive surgeries include arthroscopic, endoscopic, laparoscopic, and thoracoscopic surgeries. In laparoscopic and endoscopic surgical procedures, a small incision or puncture is made in a patient's body (e.g., abdomen) to provide an entry point for a surgical access device which is inserted into the incision and facilitates the insertion of instruments used in performing surgical procedures within an internal surgical site. Minimally invasive surgical procedures are advantageous in that, as compared to traditional open surgical procedures, both trauma to the patient and recovery time are reduced due to the relatively small incisions formed through the patient's body. However, since these access incisions are small, only elongated, small diametered instrumentation may be used to access the internal body cavities and organs.

During such procedures, surgical objects such as surgical access devices (e.g., cannulae) are inserted into the patient's body through the incision in tissue. In general, prior to the introduction of the surgical object into the patient's body, insufflation gases are used to enlarge the area surrounding the target surgical site to create a larger, more accessible work area. The surgeon is then able to perform the procedure within the abdominal cavity by manipulating the instruments that have been extended through the access devices. The manipulation of such instruments within the internal body is similarly limited by both spatial constraints and the need to maintain the body cavity in an insufflated state.

SUMMARY

A surgical access device includes a housing and a tubular member extending from the housing. The tubular member has proximal and distal openings and includes an outer wall and an inner wall that define an annular lumen therebetween. A passageway extends between the proximal and distal openings and is configured to receive a surgical instrument therethrough. A conduit extends along a length of the tubular member and is disposed in the annular lumen. The conduit is transitionable between first and second states. The conduit includes spiral segments, where each spiral segment is engaged with an adjacent spiral segment such that the conduit has a flexible configuration in the first state and a fixed configuration in the second state. A valve assembly is coupled to the housing and includes a port that is in fluid communication with the annular lumen and attachable to a source of fluid.

In an aspect, a fluid may be disposed in the annular lumen.

In another aspect, the conduit may transition to the first state in the presence of fluid in the annular lumen.

In a further aspect, the conduit may transition to the second state in the absence of the fluid in the annular lumen.

In another aspect, each spiral segment may have first and second portions where each of the first and second portions may have a generally C-shaped cross-sectional configuration.

In aspects, the first portion of each spiral segment may be slidable with respect to the second portion of the adjacent spiral segment such that the conduit is in the first state.

In an aspect, the first portion of each spiral segment may be fixed with respect to the second portion of the adjacent spiral segment such that the conduit is in the second state.

In another aspect, the tubular member may be flexible and adapted to receive a flexible surgical instrument therein.

In aspects, the inner and outer walls of the annular lumen may contact surfaces of the spiral segments of the conduit.

A method of accessing a surgical site includes positioning a tubular member of a surgical access device through an opening in tissue, guiding a distal portion of the tubular member toward a target site, manipulating the tubular member to follow a predetermined path while the tubular member is in a first state, and removing fluid from an annular lumen defined between inner and outer walls of the tubular member thereby transitioning the tubular member from the first state to a second state wherein the tubular member is rigid.

In an aspect, manipulating the tubular member may include manipulating a conduit disposed in the annular lumen of the tubular member.

In another aspect, manipulating the conduit may include manipulating spiral segments of the conduit such that a first section of one spiral segment slidably engages a second section of an adjacent spiral section.

In a further aspect, removing fluid from the annular lumen may cause the inner and outer walls of the lumen to contact surfaces of the spiral segments of the conduit.

In yet another aspect, removing fluid from the annular lumen may cause first sections of spiral segments of a conduit disposed in the annular lumen to become fixed in relation to second sections of adjacent spiral segments of the conduit thereby defining the second state of the tubular member.

In an aspect, the method may include inserting a flexible surgical instrument through the tubular member while the tubular member is in the first state.

In a further aspect, removing fluid from the annular lumen may include operating a valve on a housing that is coupled to a proximal end of the tubular member.

In yet another aspect, the method may include introducing fluid into the annular lumen thereby transitioning the tubular member from the second state to the first state and may include removing the tubular member from the opening in tissue.

In one aspect, introducing fluid into the annular lumen may include operating a valve on a housing that is coupled to a proximal end of the tubular member.

Other features of the disclosure will be appreciated from the following description.

DETAILED DESCRIPTION

Descriptions of technical features of an aspect of the disclosure should typically be considered as available and applicable to other similar features of another aspect of the disclosure. Accordingly, technical features described herein according to one aspect of the disclosure may be applicable to other aspects of the disclosure, and thus duplicative descriptions may be omitted herein. Like reference numerals may refer to like elements throughout the specification and drawings.

With initial reference toFIGS.1and1A, a surgical access device according to the present disclosure is illustrated and identified as surgical access device100. Surgical access device100has a housing10and a tubular member20extending therefrom. The tubular member20is an elongate structure that is formed from a suitable biocompatible polymeric material (e.g., silicone rubber or ethylene propylene diene monomer (EPDM) rubber) with proximal and distal openings20a,20bdefining a passageway28extending therebetween. The polymeric material used for the tubular member20allows the tubular member20to be flexible in a number of directions thereby allowing numerous configurations of the tubular member20. The housing10includes an upper housing12releasably coupled to a lower housing14. A tab16extends radially from the lower housing14and is actuable to allow relative rotation between the upper and lower housings12,14. The relative rotation between the upper and lower housings12,14allows the upper and lower housings12,14to be coupled together or separated from one another. The lower housing14has a frusto-conical region18and the tubular member20extends therefrom. A valve assembly30extends laterally from the frusto-conical region18and is attachable to a source of fluid “FS” via a flexible tube36. The housing10has a channel15extending therethrough that is coaxial with the proximal opening20aof the tubular member20. Examples of suitable housings are disclosed in commonly owned U.S. Pat. No. 10,022,149 to Holsten et al. and U.S. Patent Application Publication No. 2015/0031958 to Kleyman, the contents of which are incorporated by reference herein in their entirety.

The source of fluid “FS” may provide pressurized fluid to an annular lumen26of the tubular member20and/or may provide a vacuum to the annular lumen26of the tubular member20. With brief reference toFIG.5, the annular lumen26is defined between an outer wall24, and an inner wall22of the tubular member. Fluid is introduced or evacuated from the annular lumen26through the valve assembly30. The valve assembly30includes a port32and a valve34such as a stopcock valve. The open position of the valve34allows fluid to flow between the annular lumen26and the port32while the closed position of the valve34isolates the port32from the annular lumen26. The valve assembly30is fitted into a receiver17in the frusto-conical region18of the lower housing14thereby defining a chamber19between a bottom surface of the valve assembly30and a bottom surface of the receiver17. The annular lumen26of the tubular member20is fluidly coupled to the chamber19of the receiver17via a tunnel21. With this arrangement, opening the valve34allows fluid to flow into or out of the annular lumen26. Likewise, closing the valve34inhibits fluid flow into or out of the annular lumen26.

Referring now toFIG.2, a portion of the tubular member20is shown in a first state. A strip-wound hose or conduit40is disposed in the tubular member20. The conduit40is formed from a biocompatible metal (e.g., stainless steel). As seen inFIGS.3and4, the conduit40includes interlocking spiral segments42that are helically wound between the proximal and distal openings20a,20bof the tubular member20. Each spiral segment42includes a first portion44and a second portion46. With additional reference toFIG.5, the first portion44of each spiral segment42includes a first flange44aand a first trough44b, and the second portion46of each spiral segment42includes a second flange46aand a second trough46b. A partition45connects the first and second troughs44b,46band extends orthogonally to the first and second troughs44b,46b. As such, a cross-sectional view of the spiral segments42has a square wave pattern. The first flange44ais slidably disposed in the second trough46band the second flange46ais slidably disposed in the first trough44b. In the first state of the tubular member20, the spiral segments42of the conduit40are free to move relative to one another. As such, when manipulated by the surgeon, the first flanges44aslide in the second troughs46band the second flanges46aslide in the first troughs44ballowing the surgeon to manipulate the tubular member20and the conduit40to achieve a particular orientation that follows a desired path through body tissue.

With reference toFIG.5, and as noted above, the inner wall22and the outer wall24of the tubular member20define the annular lumen26therebetween. The annular lumen26extends from a proximal end of the tubular member20to a distal end of the tubular member20. The annular lumen26has a closed distal end. When the valve34of the valve assembly30is in the closed configuration, the annular lumen26has a fluid-tight configuration. The conduit40is disposed in the annular lumen26. When the annular lumen26is filled with fluid (e.g., sterile saline, CO2, or air), the inner and outer walls22,24move away from one another defining a gap between the conduit40and the inner and outer walls22,24. In this flexible configuration (i.e., the first state), the tubular member20, including the conduit40, has multiple degrees of freedom and can be flexed and articulated into a variety configurations allowing the tubular member20to follow a desired path through tissue to reach a target site.

With reference now toFIGS.6and7, a second state of the tubular member20is illustrated. By evacuating or removing the fluid in the annular lumen26, the inner and outer walls22,24that define the annular lumen26move towards one another in the direction of arrows “A” and squeeze the conduit40between the inner and outer walls22,24thereby eliminating the gaps between the conduit40and the inner and outer walls22,24. By squeezing the spiral segments42of the conduit40between the inner and outer walls22,24of the annular lumen26, the flanges44a,46africtionally engage the troughs44b,46b. In particular, the first flanges44africtionally engage the second troughs46band the second flanges46africtionally engage the first troughs44b. As such, each spiral segment42of the conduit40is fixed relative to an adjacent spiral segment42of the conduit40. This arrangement fixes or secures the conduit40and thus the tubular member20in a specific orientation.

In contrast to the flexible state (i.e., the first state) of the tubular member20shown inFIG.1, the fixed state (i.e., the second state) of the tubular member20is shown inFIG.8. Specifically, the tubular member20in the second state maintains a desired path through body tissue “T”. This fixed path through tissue allows a flexible surgical instrument “I” to be inserted through the housing10and follow the second state of the tubular member20to a target site without deviating from the selected path.

In use, a surgeon inserts the tubular member20in the flexible or first state (FIG.1) through an opening “O” in a patient's skin “S” (FIG.8). The surgeon then maneuvers the tubular member20through tissue “T” to reach the target site. As the tubular member20is flexible in the first state, the surgeon is able to maneuver the tubular member20as needed to reach the target site even if the target site is occluded or obstructed by other structures in the body. Once the distal end of the tubular member20reaches the target site, the surgeon evacuates fluid from the annular lumen26causing the inner and outer walls22,24of the tubular member20to compress against the spiral segments42of the conduit40transitioning the tubular member20to the fixed or second state (FIG.7). In the second state, the frictional engagement between the flanges44a,46aand the troughs44b,46bof the spiral segments42maintains the configuration of the conduit40(FIG.7). As the conduit40is disposed in the annular lumen26of the tubular member20, the tubular member20also maintains the same configuration. This allows the surgeon to insert the flexible surgical instrument “I” through the housing10and the tubular member20and access the target site with the flexible surgical instrument “I” (FIG.8).

Persons skilled in the art will understand that the devices and methods specifically described herein and illustrated in the accompanying drawings are non-limiting. It is envisioned that the elements and features may be combined with the elements and features of another without departing from the scope of the disclosure. As well, one skilled in the art will appreciate further features and advantages of the disclosure.