Patent Application
20120029296
The present application relates to cannula assemblies and methods for using same in performing surgery in a patient, and more particularly, but not exclusively, relates to cannula assemblies that provide expandable working channels.
Traditional surgical procedures for pathologies located within the body involve extensive and lengthy cutting, removing, and or repositioning skin and tissue surrounding the surgical site in order for the surgeon to access the surgical site. This type of approach may cause trauma, damage, and scarring to the tissue, and also presents risks that the tissue will become infected and that a long recovery time will be required after surgery for the tissue to heal. In some cases, these invasive procedures lead to permanent scarring and pain that can be more severe than the pain leading to the surgical intervention.
Minimally invasive surgical techniques are particularly desirable in, for example, spinal and neurosurgical applications because of the need for access to locations deep within the body and the presence of vital intervening tissues. The development of percutaneous minimally invasive spinal procedures has yielded a major improvement in reducing recovery time and post-operative pain because they require minimal, if any, muscle dissection and can be performed under local anesthesia. These benefits of minimally invasive techniques have also found application in surgeries for other locations in the body where it is desirable to minimize tissue disruption and trauma. However, current techniques for minimally invasive surgery can require numerous steps before access is gained to the surgical site which can lead to prolonged retraction of tissues and increased complexity and duration of the surgical procedure, amongst other things. Thus, there remains a need for further improvements in the devices, instruments, assemblies, apparatuses, systems and methods for performing minimally invasive and other surgical techniques.
One nonlimiting embodiment of the present application is directed to an expandable cannula assembly for use in percutaneous surgical procedures. The cannula assembly includes an elongate body extending along a longitudinal axis between a first end and a second end. The elongate body includes a pair of elongate members that cooperate to define a working channel extending from a proximal end to a distal end and being expandable from a first, unexpanded configuration to a second, expanded configuration. The elongate members are displaceable away from one another along the longitudinal axis from the proximal end to the distal end of the working channel in order to expand the working channel from the first configuration to the second configuration. In one aspect of this embodiment, the elongate members engage with one another to lock the working channel in the second configuration and prevent movement of the elongate members toward one another.
In another embodiment, an expandable cannula assembly includes an elongate body extending along a longitudinal axis between a first end and a second end. The elongate body includes a first member partially enclosing a first hollow interior and a second member partially enclosing a second hollow interior. The hollow interiors cooperate to define a working channel extending between a proximal end and a distal end. The working channel is expandable along the longitudinal axis from a first, unexpanded configuration where the second member is positioned in the first hollow interior to a second, expanded configuration by laterally displacing the first and second members away from one another from the proximal end to the distal end. In one aspect of this embodiment, at least a portion of the second member extends outwardly from the first hollow interior of the first member.
In yet another embodiment, a cannula assembly includes an elongate body extending along a longitudinal axis between a first end and a second end. The elongate body includes a first elongate member and a second elongate member cooperating to define a working channel extending from a proximal end to a distal end and being expandable from a first, unexpanded configuration to a second, expanded configuration. The first and second elongate members are displaceable from one another along the longitudinal axis from the proximal end to the distal end of the working channel to expand the working channel to the second configuration. In one aspect of this embodiment, the working channel includes a length between the proximal end and the distal end that is greater than a maximum dimension across the working channel in the second configuration. Still, in another aspect of this embodiment, the first elongate member includes a first portion extending about a second portion of the second elongate member from the proximal end to the distal end of the working channel.
In a further embodiment, a method includes providing a first cannula extending between opposite first and second ends and including a pair of elongate members cooperating to define a first working channel extending between a proximal end and a distal end and being expandable from a first, unexpanded configuration to a second, expanded configuration. A first one of the elongate members is positioned in a second one of the elongate members when the first working channel is in the first configuration. The method also includes positioning the first cannula with the first working channel in the first configuration at a location adjacent to a surgical site and displacing the elongate members laterally away from one another from the proximal end to the distal end of the first working channel to expand the first working channel to the second configuration. Displacing the elongate members includes radially expanding the second one of the elongate members to facilitate expulsion of a portion of the first one of the elongate members from the second one of the elongate members. Still, other methods for using expandable cannula assemblies are also provided.
Another embodiment of the present application is a unique system for surgery in a patient. Other embodiments include unique methods, systems, devices, kits, assemblies, equipment, and/or apparatus for use in connection with percutaneous surgical procedures. However, in other embodiments, different forms and applications are envisioned.
Further embodiments, forms, features, aspects, benefits, objects and advantages of the present application shall become apparent from the detailed description and figures provided herewith.
For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. Any such alterations and further modifications in the illustrated devices and described methods, and any such further applications of the principles of the invention as illustrated herein are contemplated as would normally occur to one skilled in the art to which the invention relates.
Instruments, systems, apparatuses, assemblies and methods for performing surgery, including spinal surgeries that include one or more techniques such as laminotomy, laminectomy, foramenotomy, facetectomy, discectomy, interbody fusion, spinal nucleus or disc replacement, and implant insertion including interbody implants and bone engaging fasteners, for example, are provided. The surgery is performed through a working channel or passageway through skin and/or tissue of the patient provided by an expandable cannula assembly. In one form, viewing of the surgical site at the working end of the cannula assembly can be accomplished with naked eye visualization, microscopic viewing devices, loupes, viewing instruments mounted on the cannula, positioned over the cannula, positioned in other portals in the body, and/or through a viewing system such as lateral fluoroscopy. The cannula assembly is movable in situ to increase the size of the working channel to facilitate access to the working space at the distal end of the cannula assembly while minimizing trauma to tissue surrounding the cannula assembly. The cannula assembly can be used with any surgical approach to the spine, including anterior, posterior, posterior mid-line, lateral, postero-lateral, and/or antero-lateral approaches, and in other regions besides the spine.
In one embodiment, an expandable cannula assembly for use in percutaneous surgical procedures includes an elongate body extending along a longitudinal axis between a first end and a second end. The elongate body includes a pair of elongate members that cooperate to define a working channel extending from a proximal end to a distal end and being expandable from a first, unexpanded configuration to a second, expanded configuration. The elongate members are displaceable away from one another along the longitudinal axis from the proximal end to the distal end of the working channel in order to expand the working channel from the first configuration to the second configuration. In one aspect, the elongate members engage with one another to lock the working channel in the second configuration and prevent movement of the elongate members toward one another. Still, it should be appreciated that alternative forms, aspects, configurations, arrangements and methods are contemplated with respect to the subject matter disclosed and described herein.
Referring now generally to
Elongate member 18 includes a first perimeter length around its exterior surface 26 between distal end 16 of elongate body 12 and proximal end 24 of working channel 22 and a second, smaller perimeter length around its exterior surface 26 between proximal end 24 of working channel 22 and proximal end 14 of elongate body 12 along a stem portion 28. Elongate member 20 also includes a first perimeter length around its exterior surface 30 (shown in
As illustrated in
Elongate member 20 includes a sidewall 44 having a generally u-shaped configuration in a plane extending orthogonally to longitudinal axis L. However, it should be appreciated that alternative configurations for sidewall 44 are also contemplated, including a generally c-shaped configuration for example. In the illustrated form, sidewall 44 includes an arcuately rounded portion 46 extending between and connected to a first linear portion 48 and an oppositely positioned second linear portion 50 by a pair of rounded transition portions 46a, 46b, respectively. Sidewall 44 further defines an opening 52 positioned between first and second linear portions 48, 50 at an end positioned opposite of arcuately rounded portion 46. Opening 52 is laterally offset from longitudinal axis L and communicates with a hollow interior 54 that is enclosed by sidewall 44 with the exception of opening 52. Moreover, first linear portion 48 includes a receptacle 56 that is positioned opposite of arcuately rounded portion 46 and is configured to receive first end portion 38 of sidewall 34 when working channel 22 is enlarged to the expanded configuration. Similarly, second linear portion 50 includes a receptacle 58 that is positioned opposite of arcuately rounded portion 46 and is configured to receive second end portion 40 of sidewall 34 when working channel 22 is enlarged to the expanded configuration. Receptacles 56, 58 generally extend orthogonally to axes upon which the remaining portions of linear portions 48, 50 extend. Further details regarding the engagement of first and second end portions 38, 40 with receptacles 56, 58 will be provided below.
Working channel 22 is illustrated in an unexpanded configuration in
Cannula assembly 10 further includes a first tab member 60 coupled to stem portion 28 of elongate member 18 and a second tab member 62 coupled to stem portion 32. However, in certain embodiments, where stem portions 28, 32 are not included for example, it is contemplated that tab members 60, 62 will not be included by cannula assembly 10. As illustrated in
Elongate body 12 of cannula assembly 10 is insertable through an incision in skin and tissue of a patient to provide working channel 22 to a surgical site. It is contemplated that elongate body 12 can initially be inserted through skin and tissue in an insertion configuration for working channel 22 such as the configuration illustrated in
More particularly, in order to expand working channel 22, tab members 60, 62 are first separated from one another. While not illustrated, it should be appreciated that in one form tab members 60, 62 could be separated from one another by distally moving a tapered separation instrument through elongate passage 64 until projections 60a are released from indentations 62b and projections 62a are released from indentations 60b. Once released from engagement with one another, the proximal ends of tab members 60, 62 may be pivoted distally away from the longitudinal axis L to position tab members 60, 62 in the configuration illustrated in
As tab members 60, 62 are separated from one another as indicated by directional arrows A, elongate members 18, 20 are moved away from one another and transition portions 46a, 46b of elongate member 20 adjacent proximal end 24 of working channel 22 are brought into further engagement with interior surface 27 of elongate member 18. As this occurs, elongate member 18 is radially expanded about longitudinal axis L, thereby increasing the distance across opening 36 and allowing a portion of elongate member 20 to be expelled or displaced from hollow interior 42 of elongate member 18. Upon continued lateral displacement of elongate member 20 from hollow interior 42, first and second end portions 38, 40 of sidewall 34 of elongate member 18 are received in receptacles 56, 58 as illustrated in
Once working channel 22 is expanded adjacent to proximal end 24, a separation instrument 70 can be inserted into working channel 22 and moved distally therethrough in order to displace elongate member 20 from hollow interior 42 such that working channel 22 has an expanded configuration from proximal end 24 to distal end 16. Moreover, in this configuration, first and second end portions 38, 40 are received in receptacles 56, 58 from proximal end 24 to distal end 16 such that a portion of elongate member 18 extends about or is positioned around elongate member 20 from proximal end 24 to distal end 16. As illustrated in
While not previously discussed, it should be appreciated that the engagement between first and second end portions 38, 40 and receptacles 56, 58 maintains working channel 22 in the expanded configuration and prevents elongate members 18, 20 from moving toward one another. However, it is contemplated that linear portions 48, 50 of elongate member 20 could be squeezed or moved together in order to disengage first and second end portions 38, 40 from receptacles 56, 58. Once disengaged, elongate members 18, 20 could be forced together to radially expand elongate member 18 and allow elongate member 20 to be repositioned into hollow interior 42. In addition, separation instrument 70 generally includes a handle portion 72 coupled with a head portion 74 which, in the illustrated form, is provided with an external configuration that generally corresponds to the internal configuration of working channel 22 in its expanded configuration. However, it should be appreciated that alternative configurations for head portion 74 are also contemplated provided that such configurations accomplish full expansion of working channel 22. For example, in one form, head portion 74 could simply be provided with a height that corresponds to the maximum dimension D across working channel 22 in its expanded configuration to ensure that working channel 22 is fully expanded as separation instrument 70 is moved distally therethrough. In another form, it is contemplated that head portion 74 could be an implant that is releasably engaged with handle portion 72 and expands working channel 22 as it is inserted therethrough to the surgical site.
In an alternative form for expanding working channel 22, it is contemplated that separation of elongate members 18, 20 could be accomplished by separation instrument 70 alone without separating tab members 60, 62 from one another to initially align first and second end portions 38, 40 with receptacles 56, 58 adjacent to proximal end 24 of working channel 22. For example, it is contemplated that head portion 74 of separation instrument 70 could he provided with a tapered configuration that can be inserted into proximal end 24 of working channel 20 once tab members 60, 62 have been pivoted away from longitudinal axis L. Similarly, in this configuration the tapered head portion 74 could be moved distally to displace elongate members 18, 20 from one another.
In a further aspect, it should be appreciated that tab members 60, 62 can be engaged with one or more operating room support structures when they are pivoted away from longitudinal axis L as illustrated in
Elongate members 18, 20 can be provided with sufficient rigidity between distal end 16 and proximal end 24 of working channel 22 to separate and maintain separation of tissue when tissue is retracted by moving elongate members 18, 20 away from one another. For example, elongate members 18, 20 can include a thickness which provides sufficient rigidity to resist bending or bowing under the forces exerted on it by the retracted tissue. Also, the arcuately shaped portions of sidewalls 34, 44 can assist in providing a sufficient section modulus or moment of inertia in the direction of movement of elongate members 18, 20 to resist bending, bowing and/or deflection forces applied during such movement. Furthermore, it is contemplated that elongate members 18, 20 can be made from any biocompatible material, including but not limited to non-reinforced polymers, carbon-reinforced polymer composites, shape-memory alloys, titanium, titanium alloys, cobalt chrome alloys, stainless steel and others as well.
An alternative embodiment cannula assembly 110 is illustrated in section view in
More particularly, as illustrated in
While not previously discussed, it should be appreciated that working channel 122 of assembly 110 can be expanded in a manner similar to that described above with respect to working channel 22 of assembly 10. For example, assembly 110 could be inserted with working channel 122 in an unexpanded configuration followed by expansion using a separation instrument to separate elongate members 118, 120 from one another either alone or in combination with initiating separation of elongate members 118, 120 by moving the tab members away from one another as discussed above with respect to assembly 10.
One particular application for cannula assemblies 10, 110 is in spinal surgery. For example, with further reference to
With reference to
As illustrated in
Upon completion of the surgical procedure, cannula assembly 10 can be disengaged from any operating room support structures, if utilized, and then removed from its location adjacent to the surgical site with working channel 22 in its expanded configuration. However, it is also contemplated that working channel 22 could be reduced to its unexpanded configuration as discussed above before cannula assembly 10 is removed from its location adjacent to the surgical site.
Alternative configurations and uses of the cannula assemblies described herein are also contemplated. For example, in one form, one or more additional cannula assemblies could be positioned at one or more other vertebral levels of the spinal column in order to perform a surgical procedure across multiple levels of the spinal column. In addition, the cannula assemblies and methods described herein may also be used in surgical procedures involving animals, or in demonstrations for training, education, marketing, sales and/or advertising purposes. In addition, the cannula assemblies and methods described herein may also be used on or in connection with a non-living subject such as a cadaver, training aid or model, or in connection with testing of surgical systems, surgical procedures, orthopedic devices and/or apparatus.
Any theory, mechanism of operation, proof, or finding stated herein is meant to further enhance understanding of the present application and is not intended to make the present application in any way dependent upon such theory, mechanism of operation, proof, or finding. It should be understood that while the use of the word preferable, preferably or preferred in the description above indicates that the feature so described may be more desirable, it nonetheless may not be necessary and embodiments lacking the same may be contemplated as within the scope of the application, that scope being defined by the claims that follow. In reading the claims it is intended that when words such as “a,” “an,” “at least one,” “at least a portion” are used there is no intention to limit the claim to only one item unless specifically stated to the contrary in the claim. Further, when the language “at least a portion” and/or “a portion” is used the item may include a portion and/or the entire item unless specifically stated to the contrary.
While the application has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the selected embodiments have been shown and described and that all changes, modifications and equivalents that come within the spirit of the application as defined herein or by any of the following claims are desired to be protected.
