Patent Application
20070156025
In surgical procedures, it is important to minimize trauma to the patient and damage to tissue to facilitate patient recovery. One way to accomplish this is to minimize the size of the incision for the surgical procedure and minimize the cutting of tissue to access the target anatomy. A number of retractors are available that are designed to expand a small surgical incision and provide access to a surgical site. Such retractors typically include two or more retractor blades that separate to expand the incision and create an access channel through which to conduct the surgical procedure. One problem with such retractors is that the access channel of the expanded retractor is often restricted to one shape or configuration.
Disclosed herein are surgical retractors and methods of minimally invasive surgery that minimize tissue trauma and facilitate access to a surgical site. In one exemplary embodiment, a surgical retractor comprises a plurality of blade assemblies interconnected by a plurality of racks. One or more of the blade assemblies may be movable along a rack to selectively expand the retractor. At least one of the blade assemblies includes a blade that is rotatably connected to the blade assembly and that may be rotatable independent of other blades of the retractor.
In another exemplary embodiment, a surgical retractor may comprise a first blade assembly, a second blade assembly, a third blade assembly, and a fourth blade assembly. The first blade assembly may be connected by a first rack to the third blade assembly and the first blade assembly may be movable along the first rack relative to the third blade assembly. The first blade assembly may be connected by a second rack to the fourth blade assembly and the fourth blade assembly may be movable along the second rack relative to the first blade assembly. The second blade assembly may be connected by a third rack to the third blade assembly and the third blade assembly may be movable along the third rack relative to the second blade assembly. The second blade assembly may be connected by a fourth rack to the fourth blade assembly and the second blade assembly may be movable along the fourth rack relative to the fourth blade assembly. The first blade assembly may include a first blade that is rotatable independent of blades of the other blade assemblies.
In accordance with another exemplary embodiment, a surgical retractor may comprise a first blade assembly having a first blade connected thereto and a second blade assembly having a second blade connected thereto. The first blade assembly may be connected by a first rack to the second blade assembly and at least one of the first blade assembly and the second blade assembly may be movable along the first rack. The first blade assembly may be connected by a second rack to the second blade assembly and at least one of the first blade assembly and the second blade assembly may be movable along the second rack. The retractor may be adjustable between a closed configuration in which the first blade assembly and second blade assembly are proximate one another at at least the proximal end thereof and an expanded configuration in which the first blade assembly and the second blade assembly are displaced from another. The first blade may be rotatably connected to the first blade assembly and may be rotatable independent of the second blade relative to the first blade assembly. The second blade may be rotatably connected to the second blade assembly and may be rotatable independent of the first blade relative to the second blade assembly.
An exemplary method of providing minimally invasive access to spinal anatomy may comprise making an incision and inserting a plurality of blades of a retractor through the incision. The retractor may comprise a plurality of blades interconnected by a plurality of racks. The exemplary method may include advancing the distal ends of the plurality blades into proximity to the spinal anatomy with the blades in a closed configuration in which the blades a proximate each other to form a continuous approximately enclosed access channel between the skin and the distal ends of the blades. The exemplary method may further include displacing one or more of the blades from the other blades by moving the blade along a rack to expand the working channel and rotating a first one of the blades independent of the other blades about a rotation axis to expand the access channel.
These and other features and advantages of the surgical retractors and methods disclosed herein will be more fully understood by reference to the following detailed description in conjunction with the attached drawings in which like reference numerals refer to like elements through the different views. The drawings illustrate principles of the devices and methods disclosed herein and, although not to scale, show relative dimensions.
Certain exemplary embodiments will now be described to provide an overall understanding of the principles of the structure, function, manufacture, and use of the devices and methods disclosed herein. One or more examples of these embodiments are illustrated in the accompanying drawings. Those of ordinary skill in the art will understand that the devices and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary embodiments and that the scope of the present invention is defined solely by the claims. The features illustrated or described in connection with one exemplary embodiment may be combined with the features of other embodiments. Such modifications and variations are intended to be included within the scope of the present invention.
The articles “a” and “an” are used herein to refer to one or to more than one (i.e. to at least one) of the grammatical object of the article. By way of example, “an element” means one element or more than one element.
The terms “comprise,” “include,” and “have,” and the derivatives thereof, are used herein interchangeably as comprehensive, open-ended terms. For example, use of “comprising,” “including,” or “having” means that whatever element is comprised, had, or included, is not the only element encompassed by the subject of the clause that contains the verb.
The surgical retractors disclosed herein may include a plurality of blade assemblies 12 that may include tissue engaging blades 16 that define an access channel 20 for the retractor. Any number of blade assemblies 12 may be provided. For example, a surgical retractor may include two blade assemblies, three blade assemblies, or four blade assemblies. The number (and size and shape) of blade assemblies may vary depending on, for example, the size and shape of the access channel desired, the procedure being performed, and the surgical approach, e.g. posterior, anterior, or lateral. The illustrated exemplary surgical retractor 10 includes four blade assemblies: first blade assembly 12a, second blade assembly 12b, third blade assembly 12c, and fourth blade assembly 12d.
The blade assemblies 12 of the retractors disclosed herein may be interconnected by a number of racks 14 that allow selective displacement of the blade assemblies from one another to expand the access channel of the retractor. The number of racks 14 provided can vary depending on, for example, the desired expansion of the access channel. In the illustrated embodiment, the retractor 10 includes four racks: first rack 14a, second rack 14b, third rack 14c, and fourth rack 14d. In particular, the first blade assembly 12a may be connected by the first rack 14a to the third blade assembly 12c and the first blade assembly 12a may be movable along the first rack 14a relative to the third blade assembly 12c. The first blade assembly 12a may be connected by the second rack 14b to the fourth blade assembly 12d and the fourth blade assembly 12d may be movable along the second rack 14b relative to the first blade assembly 12a. The second blade assembly 12b may be connected by the third rack 14c to the third blade assembly 12c and the third blade assembly 12c may be movable along the third rack 14c relative to the second blade assembly 12b. The second blade assembly 12b may be connected by the fourth rack 14d to the fourth blade assembly 12d and the second blade assembly 12b may be movable along the fourth rack 14d relative to the fourth blade assembly 12d.
In another exemplary embodiment, a retractor may include a first a first blade assembly having a first blade connected thereto and a second blade assembly having a second blade connected thereto. A first rack may connect the first blade assembly and the second blade assembly and the first blade assembly and/or the second blade assembly may be movable along the first rack. A second rack may connect the first blade assembly and the second blade assembly and the first blade assembly and/or the second blade assembly may be movable along the second rack.
The retractors disclosed herein may include a mechanism for selectively locking the position of a blade assembly 12 relative a rack 14. In the illustrated embodiment, for example, the retractor 10 includes a ratchet mechanism for selectively displacing a blade assembly 12 relative to a respective rack 14. Each rack 14a-d includes a plurality of teeth 18a-d extending along the length of the rack 14. Each blade assembly 12a-d includes a complementary pawl that can selectively engage the teeth 18 of a respective rack to lock the position of the blade assembly 12 relative to the rack 14, when the teeth are engaged by the pawl, or to release the blade assembly 12 from the rack 14 to permit motion along the rack 14 when the pawl is disengaged from the rack. One skilled in the art will appreciate that other mechanisms, including, for example, a screw or the like that may be selectively advanced relative to the blade assembly into contact with the respective rack, may be employed to permit selective displacement of a blade assembly relative to a rack.
The shape of a rack 14 along its longitudinal axis can be varied to provide an expanded access channel having a different size and shape. In the illustrated exemplary embodiment, for example, all of the racks 14a-d of the surgical retractor 10 are linear. In such a configuration, the blade assemblies 12a-d may be displaced along a respective rack 14a-d with each blade 16a-d remaining parallel in orientation with respect to the other blades. In alternative embodiments, one or more of the racks 14 may be arcuate along its length to permit lateral and angular expansion of the access channel or may be flexible or hinged allowing for variable angular expansion.
In the exemplary retractors disclosed herein, the blade 16 of one or more of the blade assemblies 12 of the retractor may be rotationally adjustable relative to the blade assembly and the blade 16 may be rotatable independent of other blades of the retractor. For example, a blade 16 may be rotationally connected to the blade assembly. In the exemplary embodiment, the blade assemblies 12a-d each include a blade 16a-d that is rotationally connected to its respective blade assembly. In such a configuration, each blade 16a-d may rotate relative to the respective blade assembly 12a-d independent of the other blades to selectively expand the access channel 20 of the retractor 10. In the illustrated embodiment, the proximal end 22 of each blade 16 can be configured to facilitate rotational connection of the blade 16 to the blade assembly 12. Referring to
The retractors disclosed herein may be adjustable between a closed configuration, illustrated in
The retractor 10 may include a blade adjustment mechanism for selectively adjusting the rotational position of a rotationally adjustable blade. Referring to the first blade assembly 12a, for example, the blade adjustment mechanism of the exemplary retractor 10 may be a pawl 30a connected to blade assembly 12a for selectively engaging a plurality of teeth 40a provided on the proximal end 22a of a blade 16a. Each blade assembly of the exemplary retractor 10 may include an analogous adjustment mechanism, as in the illustrated retractor 10, or may have distinct blade adjustment mechanisms. Continuing to refer to first blade assembly 16a and
In alternative embodiments, the blade adjustment mechanism may have a different structure. Referring to
Alternatively, the blade adjustment mechanism may include a screw received within a threaded bushing connected to the first blade. Rotation of the screw may cause the bushing to move along an axis of the screw to adjust the rotational orientation of the first blade.
Referring to
Referring to
Referring to
Referring to
One skilled in the art will appreciate that other blade adjustment mechanisms may be employed to adjust the rotational position of a rotationally adjustable blade.
One or more of the blades of the retractor may have an adjustable length, e.g. the blade may telescope to selectively adjust the length of the blade. Referring to the exemplary embodiment illustration in
The components of the retractors disclosed herein may be manufactured from any biocompatible material including metals, such as stainless steel or titanium, polymers, or composite materials. The components, such as the blades and the frame, may be constructed from the same or different materials.
An exemplary method of providing minimally invasive access to spinal anatomy employing a retractor disclosed herein may include making a skin incision for insertion of the retractor. The incision initially may be less that the diameter of the retractor in the closed configuration (e.g., with the blades of the device in the first, closed position). The incision may be expanded to accommodate the retractor by dilation, for example, by placing one or more dilators through the incision to expand the incision in a stepwise manner. The dilators may be employed to separate or dissect the underlying tissue to the target spinal anatomy. Alternatively, the surgeon may employ his finger or the retractor to dissect the underlying tissue and to expand the initial incision.
The blades of a retractor may be inserted through the incision and the distal ends of the blades may be advanced into proximity to the spinal anatomy. The blades are preferably advanced in a first, closed position, in which the blades are proximate to or contact each other to form a continuously approximately enclosed access channel between the frame, which may be located at the surface of the skin, and the distal ends of the blades. One or more of the blade assemblies may be displaced from the other blade assemblies by moving the blade assembly along a respective rack and thereby expanding the access channel. One or more of the blades may be rotated, using a blade adjustment mechanism, independent of the other blades, to selectively expand the access channel. In the case of the exemplary retractor 10, rotational adjustment of some or all of the blades of the device expands the access channel, particularly at the distal end of the access channel, thereby creating greater working space at proximate the target spinal anatomy. In addition, the length of the working channel may be increased by advancing an adjustable blade of one of the plurality of blades relative to a primary blade along a longitudinal axis of the primary blade.
Any number of surgical procedures may be performed through the access channel including, for example, removal of some or all of one or more discs, placement of bone fusion promoting material, placement of an spine arthroplasty device such as an artificial disc, placement of spinal implants such as hooks, rods, and screws.
After the surgical procedure is performed, the retractor may be returned to the closed configuration and removed from the incision.
While the surgical retractors and methods of the present invention have been particularly shown and described with reference to the exemplary embodiments thereof, those of ordinary skill in the art will understand that various changes may be made in the form and details herein without departing from the spirit and scope of the present invention. Those of ordinary skill in the art will recognize or be able to ascertain many equivalents to the exemplary embodiments described specifically herein by using no more than routine experimentation. Such equivalents are intended to be encompassed by the scope of the present invention and the appended claims.
