Patent Description:
The disclosed guides, systems, and methods are directed to surgical implants. More particularly, the disclosed guides, systems, and methods are directed to providing intraoperative alignment for one or more cutting guides.

Joint replacement surgeries seek to replace the joint of a patient such that the joint functions as well as a native joint. Various guides typically are used in performing these surgeries, including guides for resecting one or more bones comprising the joint as well as ensuring the proper alignment and placement of the prosthesis. For example, these guides may provide a surgeon with the ability to visualize and/or approximate a mechanical axis of one or more bones of the patient.

<CIT> discloses a laser-based implant guide system that aligns an implant with an axis of an anatomical structure of interest. The system includes a target base configured to couple to a patient in alignment with the axis, and a target member configured to couple to the target base that includes a visual indication of the location of the axis. The system further includes an implant guide that includes a laser device and a resection guide. The implant guide is configured to adjust at least one of the position and the orientation of the laser device with respect to the anatomical structure of interest such that a laser line projecting from the laser device is aligned with the visual indication of the target member, and the resection guide facilities implantation of the implant in a resected portion of the anatomical structure of interest in alignment with the axis.

The present invention is an alignment guide as defined in claim <NUM>. Additional advantageous features of the alignment guide are recited in the other claims.

In some embodiments, an alignment guide includes a base, a swing arm for coupling to the base such that the swing arm is movable relative to the base, and a locking device for selectively fixing a position of the swing arm relative to the base. The base defines at least one first hole sized and configured to receive a first fixation element and defines at least one second hole sized and configured to receive a second fixation element. The swing arm extends from a first end to a second end. The second end of the swing arm including a coupling mechanism for coupling another guide to the second end of the swing arm.

Here is also disclosed a method that is not part of the invention. The method includes positioning an alignment guide relative to a bone, adjusting a position of a swing arm of the alignment guide while a position of a base of the alignment guide remains fixed relative to the bone, fixing the position of the swing arm relative to the base, and coupling a second guide to the alignment guide. According to additional advantageous features of the method:.

This description of the exemplary embodiments is intended to be read in connection with the accompanying drawings, which are to be considered part of the entire written description.

The disclosed guides, systems, and methods provide a surgeon with the ability to confirm and/or adjust the placement of a cutting guide without the need to manually remove one or more pre-placed pins. As such, these guides, systems, and methods advantageously provide the surgeon with flexibility in the operating theater to adjust a position of a cutting guide and to perform such adjustment with precision and accuracy compared to conventional methods of manual and/or unguided adjustment.

<FIG> illustrates one example of an alignment guide in accordance with some embodiments. The alignment guide <NUM> illustrated in <FIG> may include a base <NUM> and swing arm <NUM> coupled to the base. Base <NUM> includes a body <NUM> extending from a first end <NUM> to a second end <NUM>.

In some embodiments, first end <NUM> may terminate in one or more points <NUM> or other shape for indicating alignment as will be understood by one of ordinary skill in the art. The first end <NUM> may define a hole or cavity <NUM> sized and configured to receive a spring-biased detent <NUM>. As best seen in <FIG>, spring-biased detent <NUM> may include a biasing member <NUM>, such as a compression spring, a cap <NUM>, and a detent <NUM> coupled to the biasing member <NUM>. In some embodiments, the spring-biased detent <NUM> is configured to provide audible and/or tactile feedback to a user indicating the angular adjustment of the guide <NUM> as described in greater detail below.

In some embodiments, first end <NUM> may also include a second point or indicator <NUM> is collinearly arranged with point <NUM> but oriented such that indicator <NUM> is directed in a direction that is opposite to the direction in which point <NUM> is oriented (<FIG>). As best seen in <FIG> the indicator <NUM> is positioned on a ledge <NUM>, which is located above a first upper surface <NUM> of body <NUM>. The hole or cavity <NUM> extends inwardly from vertical surface <NUM> and between upper surface <NUM> and ledge <NUM>.

In some embodiments, body <NUM> of base <NUM> defines first and second sets of interconnected holes <NUM>, <NUM>. The first and second sets of interconnected holes <NUM>, <NUM> may be spaced apart from one another along a length of body <NUM> as shown in <FIG>. In some embodiments, the sets of interconnected holes <NUM>, <NUM> extend entirely through body <NUM> of base <NUM>. Body <NUM> may also define a slot <NUM> along its length. Slot <NUM> may extend through body <NUM> and have a length that is oriented perpendicular to a longitudinal axis defined by body <NUM>. In some embodiments, slot <NUM> does not extend entirely through body <NUM>. As described in greater detail below, slot <NUM> is sized and configured to receive a dowel pin <NUM> or other device for constraining the movement of swing arm <NUM> relative to base <NUM> as will be understood by one of ordinary skill in the art. In some embodiments, slot <NUM> is provided between the second set of interconnected holes <NUM> and the end <NUM> of body <NUM>. However, one of ordinary skill in the art will understand that slot <NUM> may be formed at other locations along the length of body <NUM>. Further, slot <NUM> may be replaced with a hole sized and configured to receive the dowel pin <NUM>, and swing arm <NUM> may define a corresponding slot.

Second end <NUM> of base <NUM> may include one or more extensions <NUM>-<NUM>, <NUM>-<NUM> (collectively, "extensions <NUM>") that extend in a downward direction from the lower surface <NUM> of body <NUM>. Each extension <NUM>-<NUM>, <NUM>-<NUM> may include a respective arm <NUM>-<NUM>, <NUM>-<NUM> (collectively, "arms <NUM>" or "lower arms <NUM>") that extends from the bottom of each extension as shown in <FIG>. Second end <NUM> may also include one or more upper arms <NUM>-<NUM>, <NUM>-<NUM> (collectively, "arms <NUM>" or "upper arms <NUM>"). Arm <NUM>-<NUM> extends parallel to lower arm <NUM>-<NUM>, and upper arm <NUM>-<NUM> extends parallel to lower arm <NUM>-<NUM>. Lower arms <NUM>-<NUM>, <NUM>-<NUM> define a respective hole <NUM>-<NUM>, <NUM>-<NUM>. Upper arms <NUM>-<NUM>, <NUM>-<NUM> may also define a respective hole <NUM>-<NUM>, <NUM>-<NUM>. Hole <NUM>-<NUM> may be aligned with hole <NUM>-<NUM> such that a k-wire or other fixation device may be received within holes <NUM>-<NUM>, <NUM>-<NUM>, and hole <NUM>-<NUM> may be aligned with hole <NUM>-<NUM> such that a k-wire or other fixation device may be received within holes <NUM>-<NUM>, <NUM>-<NUM>.

In some embodiments, body <NUM> includes a projection <NUM> that extends parallel to upper arms <NUM>. Projection <NUM> may be located between arms <NUM> as best seen in <FIG>. Projection <NUM> may define a hole <NUM> sized and configured to allow a locking screw (described in greater detail below) to pass therethrough. As such, in some embodiments, the hole <NUM> has a diameter that is greater than a diameter of ball <NUM>.

Swing arm <NUM> may have an elongate body <NUM> and a housing <NUM>. A first end <NUM> of body <NUM> may include a number of teeth <NUM> arranged along a front edge <NUM> of end <NUM>. The teeth <NUM> may be sized and arranged to be engaged by the spring-biased detent <NUM> supported by base <NUM>.

In some embodiments, upper surface <NUM> of end <NUM> may include indicia <NUM>, which indicate an angle alignment as described in more detail below. As best seen in <FIG>, the indicia <NUM> may include a plurality of lines or grooves <NUM> that extend from a trough <NUM> formed between adjacent teeth <NUM>. In some embodiments, adjacent troughs <NUM> are separated by a distance corresponding a specific adjustment angle described in greater detail below. A middle or central trough <NUM> (not visible in <FIG>) may be provided that aligns with a central longitudinal axis defined by the body <NUM> of swing arm <NUM>.

As best seen in <FIG> and <FIG>, body <NUM> may include one or more oblong sections <NUM>, <NUM> that are spaced apart from one another along the length of body <NUM>. In some embodiments, oblong sections <NUM>, <NUM> have an outer contour that is similar to the contour provided by the portions of body <NUM> defining the sets of interconnected holes <NUM>, <NUM>. More particularly, the outer or peripheral contour of oblong section <NUM> may align within or be similar in shape to the outer contour or shape of the section of body <NUM> in which the first set of interconnected holes <NUM> is provided, and the outer or peripheral contour of oblong section <NUM> may align with or be similar in shape to the outer contour or shape of the section of body <NUM> in which the second set of interconnected holes <NUM> is provided.

Further, in some embodiments, a hole <NUM> is provided along oblong section <NUM> and a hole <NUM> is provided along oblong section <NUM>. Hole <NUM> is arranged such that it may be aligned with one of the holes of the first set of interconnected holes <NUM>, and hole <NUM> is arranged such that it may be aligned with one of the holes of the second set of interconnected holes <NUM>.

Body <NUM> defines another hole <NUM>, which may be positioned along the central longitudinal axis defined by the body <NUM>. Hole <NUM> may be partially or fully threaded and include a countersink or undercut section <NUM>, which may inwardly extend from the lower planar surface <NUM> of body <NUM> as best seen in <FIG>. Hole <NUM> is sized and configured to receive a locking screw <NUM> therein. As best seen in <FIG> and <FIG>, locking screw <NUM> may include an outwardly extending flange <NUM>, which may have a diameter that may be greater than a diameter of the rest of the locking screw <NUM>, and an engagement feature <NUM> at an end disposed opposite of the flange <NUM>. Flange <NUM> is sized and configured to be received within countersink or undercut section <NUM> of hole <NUM>.

In some embodiments, the upper surface <NUM> of body <NUM> may include one or more pin holders <NUM>-<NUM>, <NUM>-<NUM> (collectively, "pin holders <NUM>"). Each pin holder <NUM>-<NUM>, <NUM>-<NUM> may include a respective projection <NUM>-<NUM>, <NUM>-<NUM> (collectively, "projections <NUM>") each defining a respective hole <NUM>-<NUM>, <NUM>-<NUM> (collectively, "holes <NUM>"). Holes <NUM> may be sized and configured to receive a k-wire, pin, or other elongate object therein and are arranged such that when the k-wire, pin, or elongate object may be received within the holes <NUM>, the k-wire, pin, or other elongate object extends along a central longitudinal axis defined by swing arm <NUM>. The k-wire, pin, or other elongate object may enhance the visualization for the user to check the alignment of the swing arm <NUM> relative to a mechanical axis of the patient.

Body <NUM> may also define a hole <NUM>, which may be sized and configured to receive dowel <NUM>, and a hole <NUM>, which may be at least partially threaded. In some embodiments, hole <NUM> is positioned between pin holder <NUM>-<NUM> and end <NUM> of body <NUM>. Hole <NUM> may be positioned such that it will be aligned with hole <NUM> when the swing arm <NUM> is coupled to the base <NUM> and may be dimensioned to receive and engage locking screw <NUM> as described in greater detail below.

Housing <NUM> may extend from lower surface <NUM> of body <NUM>. In some embodiments, a gap <NUM> is provided between the lower surface <NUM> of body <NUM> and housing <NUM> such that housing <NUM> is coupled to body <NUM> by one or more appendages <NUM>-<NUM>, <NUM>-<NUM> (collectively, "appendages <NUM>"). Gap <NUM> may be dimensioned to receive projection <NUM> of base <NUM> in sliding engagement. In some embodiments, housing <NUM> includes first and second wings <NUM>-<NUM>, <NUM>-<NUM> (collectively, "wings <NUM>") extending outwardly from opposite sides <NUM>, <NUM> of housing <NUM>. Each wing <NUM>-<NUM>, <NUM>-<NUM> may define a respective slot <NUM>-<NUM>, <NUM>-<NUM> (collectively, "slots <NUM>") that are positioned on housing <NUM> such that the slots <NUM> are aligned with holes <NUM>, <NUM> when the swing arm <NUM> is coupled to base <NUM>. More particularly, slot <NUM>-<NUM> may be aligned with holes <NUM>-<NUM>, <NUM>-<NUM> when swing arm <NUM> is coupled to base <NUM>, and slot <NUM>-<NUM> may be aligned with holes <NUM>-<NUM>, <NUM>-<NUM> when swing arm <NUM> is coupled to base <NUM>. Slots <NUM> may be sized and configured to receive a k-wire, pin, or other fixation device therein while permitting the swing arm <NUM> to move relative to the k-wires, pins, or other fixation devices as described in greater detail below.

Housing <NUM> may define a chamber <NUM> sized and configured to receive a locking block <NUM>. In some embodiments, chamber <NUM> extends inwardly between side <NUM> and side <NUM> of housing <NUM> and is in communication with hole <NUM>. Hole <NUM> may be aligned with hole <NUM> defined by body <NUM> of swing arm <NUM> and be sized and configured to provide clearance for receiving locking screw <NUM>.

Locking block <NUM> may define a contoured (e.g., an oblong sphere) cavity <NUM> extending inwardly from side <NUM>. Cavity <NUM> may be contoured to facilitate engagement between locking block <NUM> and the ball <NUM> of locking screw <NUM>, which may be a ball head screw as shown in <FIG>, including a ball <NUM> coupled to a shaft <NUM>. Locking block <NUM> may include one or more slots <NUM>-<NUM>, <NUM>-<NUM> (collectively, "slots <NUM>") that extend from side <NUM> to side <NUM> of locking block <NUM>. In some embodiment, slots <NUM> are formed such that a length of the slots <NUM> is angled with respect to a planar surface provided by side <NUM>, which extends between sides <NUM>, <NUM> and is disposed adjacent to side <NUM>. Slots <NUM> may be sized and configured to receive dowel pins <NUM> or other coupling elements for coupling locking block <NUM> to housing <NUM>. For example, dowel pins <NUM> may be received within slots <NUM> of locking block <NUM> and holes <NUM> defined by the sides <NUM>, <NUM> of housing <NUM>. The combination of slots <NUM>, holes <NUM>, and cavity <NUM> may enable locking block <NUM> to move relative to housing <NUM> and facilitate locking of a cutting guide to the guide <NUM> as described below.

Housing <NUM> may include a pair of spaced apart rails <NUM>, <NUM> each defining an respective undercut <NUM>, <NUM> for forming a dovetail connection with a cutting guide, such as with the dovetail extension <NUM> of coronal sizing and drill guide <NUM> described in <CIT>, entitled "ANKLE REPLACEMENT SYSTEM AND METHOD" (the "<NUM> Patent"). A person of ordinary skill in the art will understand that housing <NUM> may include connection mechanisms other than a dovetail connection for coupling the guide <NUM> to one or more sizing and/or cutting guides.

Swing arm <NUM> may be coupled to base <NUM> by sliding projection <NUM> of base <NUM> into gap <NUM>. When projection <NUM> is received within gap <NUM>, lower arms <NUM> and upper arms <NUM> at least partially surround housing <NUM> of swing arm <NUM> such that holes <NUM>, <NUM> defined by arms <NUM>, <NUM> are aligned with slots <NUM> defined by wings <NUM>. Dowel pin <NUM> is inserted into hole <NUM> defined by swing arm <NUM> and into slot <NUM> defined by base <NUM>. The locking screw <NUM> is received within cavity <NUM> defined by locking block <NUM> and inserted into holes <NUM>, <NUM>. Locking block <NUM> is pinned to swing arm <NUM> by inserting pins <NUM> into holes <NUM> defined by the body <NUM> of swing arm <NUM> that are also received within slots <NUM> defined by locking block <NUM>.

In use, a surgeon or other individual may place one or more pins or k-wires (e.g., a <NUM> Steinmann pin) in the anterior surface of a patient's tibia based on the use of a patient-specific mount, such as patient-specific mount <NUM> and pins <NUM> described in the '<NUM> Patent. With pins inserted in the patient, the patient-specific mount <NUM> is removed from its engagement with the pins and the alignment guide <NUM> is then placed over the pins <NUM>. More particularly, the pins <NUM> are received within holes <NUM>, <NUM> defined by arms <NUM>, <NUM> and within slots <NUM> as best seen in <FIG>.

With alignment device <NUM> coupled to pins <NUM>, a surgeon or other individual may check to confirm a cutting guide will be properly oriented and/or adjust the alignment of a cutting guide without having to remove pins <NUM>. For example, varus/valgus adjustment may be made by rotating swing arm <NUM> relative to base <NUM>. As noted above, the swing arm <NUM> is able to rotate relative to base <NUM> about an axis defined by holes <NUM>, <NUM>, <NUM> in which locking screw <NUM> is received. Rotation and relative movement between swing arm <NUM> and base <NUM> is permitted by slots <NUM>, <NUM>.

As swing arm <NUM> moves relative to base <NUM>, detent <NUM> provides audible and/or tactile feedback as it engages the teeth <NUM> (and the troughs <NUM> between teeth <NUM>). Further, indicia <NUM>, if provided, indicate the amount of varus/valgus adjustment (e.g., 1º, 2º, etc.) based on movement of the swing arm <NUM>. When the desired adjustment has been achieved, the position of swing arm <NUM> to base <NUM> may be fixed using locking screw <NUM>. Rotation of screw <NUM> in a first direction (e.g., clockwise direction) may lock the position of swing arm <NUM> to base <NUM>, and rotation of screw <NUM> in a second direction (e.g., counter-clockwise direction) may permit relative movement of swing arm <NUM> to base <NUM>.

It should be appreciated that a guide, such as a coronal sizing and drill guide <NUM> or cutting guide as described in the '<NUM> Patent, may be coupled to alignment guide <NUM> prior to or after the angular adjustment is performed. Such a guide may be coupled to alignment guide <NUM> by inserting a dovetail extension into the corresponding dovetail/undercuts <NUM>, <NUM> provided by rails <NUM>, <NUM> of housing <NUM>. The cutting or drill guide may be locked to the housing <NUM> by rotating locking screw <NUM> in a first direction (e.g., counter-clockwise) as shown in <FIG>. Unlocking is provided by the ball head <NUM> engaging the surface(s) defining cavity <NUM> of locking block <NUM>, which causes locking block <NUM> to be pulled inwardly into chamber <NUM> guided by the engagement of pins <NUM> and slots <NUM> decoupling alignment guide <NUM> from the cutting and/or drill guide. Rotating the locking screw <NUM> in a second, opposite direction (e.g., clockwise) results in the locking of the cutting and/or drill guide from alignment guide <NUM>, as also indicated in <FIG>, such that the alignment guide <NUM> may be coupled to the cutting and/or drill guide. For example, the dovetail connection between the alignment guide <NUM> and the cutting and/or drill guide may be engaged by sliding the alignment guide <NUM> relative to the cutting and/or drill guide.

If desired, an elongate radiopaque member, such as a k-wire or pin, may be inserted through holes <NUM> defined by pin holders <NUM> to provide for a fluoroscopic check. For example, <FIG> illustrates a radiopaque member <NUM> being positioned within holes <NUM> defined by the pin holders <NUM> such that the radiopaque member <NUM> extends parallel to a longitudinal axis defined by the swing arm <NUM>. Under fluoroscopy, a surgeon or other individual may check to determine whether the radiopaque member <NUM> is aligned with a mechanical and/or longitudinal axis defined by a bone, such as the tibia, of the patient. A person of ordinary skill in the art will understand that the fluoroscopic check may be performed before or after the cutting and/or drill guide is coupled to the alignment guide <NUM>.

<FIG> shows alignment guide <NUM> coupled to a distal portion of a bone, which in this example is a distal portion of a tibia TB. As shown in <FIG>, the alignment guide is coupled to the bone TB via pins <NUM>, which are received within holes <NUM>, <NUM> defined by arms <NUM>, <NUM> of base <NUM> and within slots <NUM> defined by the wings <NUM> of swing arm <NUM>. A coronal sizing and drill guide <NUM> (as described in the '<NUM> Patent) is shown as coupled to alignment guide <NUM>. Pins <NUM> may be used to secure the guide <NUM> to bone.

The holes <NUM>, <NUM> defined by swing arm <NUM> provide the surgeon with the ability to form holes in a patient's bone that facilitate the use of additional instruments. For example, as shown in <FIG>, pins <NUM>, which can be the same type and size (e.g., <NUM> Steinmann) or a different type or size as pins <NUM>, may be inserted through holes <NUM>, <NUM>, which are aligned respectively with interconnected holes sets <NUM>, <NUM> defined by base <NUM>. Once pins <NUM> have been inserted, additional instrumentation, such as an adjustment block <NUM> and/or an alignment frame subassembly <NUM> described in the '<NUM> Patent, may be coupled to the pins <NUM>.

It should be appreciated, however, that the alignment guide may take other forms or configurations. Another example of an alignment guide <NUM> is shown in <FIG>. Features of alignment guide <NUM> that are common to those of alignment guide <NUM> have the same reference numeral incremented by <NUM>. Repetitive descriptions of common elements of alignment guides <NUM>, <NUM> are not provided herein.

As best seen in <FIG>, base <NUM> may havea generally rectangular shape without oblong sections and sets of interconnected holes as provided by base <NUM>. Instead, the base <NUM> may include a hole <NUM> that is sized and configured to receive a dowel or other type of pin <NUM> therein. Pin <NUM> may be sized and configured to be received within a slot <NUM> as best seen in <FIG>. The combination of slot <NUM> and pin <NUM> constrains the relative movement between swing arm <NUM> relative to base <NUM> to a predefined distance.

Oblong section <NUM> of swing arm <NUM> may include a set of interconnected holes <NUM> that are aligned with a hole <NUM> defined by base <NUM>. Swing arm <NUM> may also define a slot <NUM> that may be aligned with a hole <NUM> defined by base <NUM> as best seen in <FIG>. Thus, a person of ordinary skill in the art will understand that the arrangement of holes and slots provided by the base and swing arm may be varied.

<FIG> and <FIG> illustrate another example of an alignment guide in accordance with some embodiments. Alignment guide <NUM> may include a base <NUM> that may be coupled to a swing arm <NUM>. Base <NUM> may have an elongate body <NUM> extending from a first end <NUM> to a second end <NUM>. A housing <NUM> may be provided at the second end <NUM>. First end <NUM> of body <NUM> may include a number of teeth <NUM> arranged along a front edge <NUM>. Teeth <NUM> may be sized and configured to be engaged by a spring-biased detent <NUM> of swing arm <NUM> as described below. Indicia (not shown in FIGS. <NUM>-<NUM>) may be provided on upper surface <NUM> of body <NUM> adjacent to teeth <NUM> for providing a visual indicator to a user as to the desired angular offset as also be described below.

Body <NUM> may define a first and second slots <NUM>-<NUM>, <NUM>-<NUM> (collectively, "slots <NUM>") that extend in a widthwise direction across body <NUM> and extend entirely through body <NUM>. In some embodiments, a hole <NUM>, which may be threaded, is defined by body <NUM> between slots <NUM>. Hole <NUM> is sized and configured to receive a locking screw <NUM> therein. Body <NUM> may also define a hole <NUM>, which may be threaded, adjacent to end <NUM>. In some embodiments, body <NUM> includes a pin holder <NUM> extending upwards from upper surface <NUM>. Pin holder <NUM> may include a projection <NUM> that defines a hole <NUM> that is sized and configured to receive an elongate radiopaque member, such as a k-wire or pin, as will be understood by one of ordinary skill in the art. Pin holder <NUM> may be positioned such that a central axis defined by hole <NUM> aligns with a longitudinal axis defined by the elongate body <NUM> of base <NUM>.

Housing <NUM> may extend from lower surface <NUM> of body <NUM>. In some embodiments, a gap <NUM> is provided between the lower surface <NUM> of body <NUM> and housing <NUM> such that housing <NUM> is coupled to body <NUM> by one or more appendages <NUM>-<NUM>, <NUM>-<NUM> (collectively, "appendages <NUM>"). Gap <NUM> is dimensioned to receive the body <NUM> of swing arm <NUM> in sliding engagement as described below and shown in <FIG>. In some embodiments, housing <NUM> includes first and second wings <NUM>-<NUM>, <NUM>-<NUM> (collectively, "wings <NUM>") that extend outwardly from opposed sides <NUM>, <NUM> of housing <NUM>. Each wing <NUM>-<NUM>, <NUM>-<NUM> may define a plurality of interconnected holes <NUM>-<NUM>, <NUM>-<NUM> (collectively, "holes <NUM>"). It should be understood that although a plurality of interconnected holes <NUM> are shown, the plurality of holes <NUM> may be implemented as unconnected (i.e., separate) holes, as a single hole, or as a slot. In some embodiments, holes <NUM> are arranged such that they extend perpendicular to the longitudinal axis defined by the elongate body <NUM> of base <NUM>, although one of ordinary skill in the art will understand that holes <NUM> may be arranged or oriented at other angles with respect to the longitudinal axis defined by elongate body <NUM> of base <NUM>.

Housing <NUM> may define a chamber <NUM> that extends inwardly between sides <NUM>, <NUM> and is in communication with hole <NUM>. Chamber <NUM> may be sized and configured to receive a locking block <NUM>, which may be secured within chamber <NUM> via pins <NUM>-<NUM>, <NUM>-<NUM> (collectively, "pins <NUM>") that are received within slots <NUM>-<NUM>, <NUM>-<NUM> (collectively, "slots <NUM>") defined by locking block <NUM> and holes <NUM>-<NUM>, <NUM>-<NUM> (collectively, "holes <NUM>") defined by housing <NUM>. Locking block <NUM> may define a contoured (e.g., oblong) cavity <NUM> that extends inwardly from side <NUM>. Cavity <NUM> may be contoured to facilitate engagement between locking block <NUM> and the ball head <NUM> of locking screw <NUM>. The combination of slots <NUM> and contoured cavity <NUM> enables locking block <NUM> to move relative to housing <NUM> and facilitate the locking of a sizing and/or cutting guide to the guide <NUM> as described below.

Housing <NUM> may include a pair of spaced apart rails <NUM>, <NUM> each defining a respective undercut for forming a dovetail connection with a cutting guide, such as with the dovetail extension <NUM> of coronal sizing and drill guide <NUM> described in the '<NUM> Patent previously cited. A person of ordinary skill in the art will understand that housing <NUM> may include connection mechanisms other than a dovetail connection for coupling the guide <NUM> to one or more sizing and/or cutting guides.

Swing arm <NUM> may have an elongate body <NUM> extending from a first end <NUM> to a second end <NUM>. First end <NUM> may terminate in one or more points <NUM> or other features for providing an indication of direction as will be understood by one or ordinary skill in the art. A hole or cavity <NUM> sized and configured to receive a spring-biased detent <NUM> may be defined adjacent to end <NUM>. Spring-biased detent <NUM> may include a biasing member <NUM>, a cap <NUM>, and a detent body <NUM> as best seen in <FIG>. In some embodiments, the spring-biased detent <NUM> is configured to provide audible and/or tactile feedback to a user indicating the angular adjustment of guide <NUM> as described in greater detail below.

First end <NUM> may also include a second point or indicator <NUM> that is aligned with point <NUM>, but points in the opposite direction. As best seen in <FIG>, indicator <NUM> may be positioned on a ledge <NUM> that is located above an upper surface <NUM>. The hole or cavity <NUM> extends inwardly from vertical surface <NUM> and between ledge <NUM> and upper surface <NUM>. Body <NUM> of swing arm <NUM> may define first and second holes <NUM>-<NUM>, <NUM>-<NUM> (collectively, "holes <NUM>") that are positioned along body <NUM> such that they are aligned with slots <NUM> when swing arm <NUM> is coupled to base <NUM>. Body <NUM> may also define a hole <NUM> that is sized and configured to provide clearance for locking screw <NUM> and is positioned along body <NUM> to be aligned with hole <NUM> defined by base <NUM>.

Guide <NUM> may be assembled by threading locking screw <NUM> into hole <NUM> defined by body <NUM> of base <NUM>. Although not shown in <FIG> and <FIG>, hole <NUM> may include an undercut section, like undercut section <NUM> of hole <NUM> shown in <FIG>, so that flange <NUM> of locking screw <NUM> may be received within the undercut section. Body <NUM> of swing arm <NUM> may be placed into abutment with the body <NUM> of base <NUM> and end <NUM> of swing arm <NUM> may be inserted into gap <NUM> between body <NUM> and housing <NUM> such that hole <NUM> is aligned with hole <NUM>. With holes <NUM>, <NUM> aligned with one another, ball head <NUM> of locking screw <NUM> may be placed within cavity <NUM> of locking block <NUM>, then locking screw <NUM> may be threaded into hole <NUM>. Locking block <NUM> may be pinned to housing <NUM> by inserting pins <NUM> into holes <NUM> and through slots <NUM>. In some embodiments, a dowel pin <NUM> may be received within a hole defined by swing arm <NUM> in a press-fit engagement and received within a cavity or slot formed in the bottom surface of body <NUM> of base <NUM> to limit the rotational movement of swing arm <NUM> relative to base <NUM> as will be understood by one of ordinary skill in the art.

In use, a surgeon or other individual may place one or more pins or k-wires in the anterior surface of a patient's tibia based on the use of a patient-specific mount, such as patient-specific mount <NUM> and pins <NUM> described in the '<NUM> Patent. With pins inserted in the patient, the patient-specific mount is removed from its engagement with the pins and the alignment guide <NUM> is the placed on the pins. More particularly, pins <NUM> may be received within holes <NUM> defined by wings <NUM> of base <NUM>.

With alignment device <NUM> coupled to pins <NUM>, a surgeon or other individual may check to confirm a cutting guide will be properly oriented and/or adjust the alignment of a cutting guide. For example, varus/valgus adjustment may be made by rotating swing arm <NUM> relative to base <NUM>. As noted above, the swing arm <NUM> is able to rotate relative to base <NUM> about an axis defined by holes <NUM>, <NUM> in which locking screw <NUM> is received. Rotation and relative movement between swing arm <NUM> and base <NUM> is permitted by slots <NUM> and a cavity or slot formed in the bottom surface of body <NUM> of base <NUM> in which dowel <NUM> is received.

As swing arm <NUM> moves relative to base <NUM>, spring-biased detent <NUM> provides audible and/or tactile feedback as detent <NUM> engages teeth <NUM> (and the troughs between teeth <NUM>). Further, indicia, if provided, indicate the amount of varus/valgus adjustment (e.g., 1º, 2º, etc.) based on movement of the swing arm <NUM> relative to the base <NUM>. When the desired adjustment has been achieved, the position of swing arm <NUM> may be fixed using locking screw <NUM>. Rotation of screw <NUM> in a first direction (e.g., clockwise direction) may lock the position of swing arm <NUM> to base <NUM>, and rotation of screw <NUM> in a second direction (e.g., counter-clockwise direction) may permit relative movement of swing arm <NUM> to base <NUM>.

It should be appreciated that a guide, such as a coronal sizing and drill guide <NUM> or cutting guide as described in the '<NUM> Patent, may be coupled to alignment guide <NUM> prior to or after the angular adjustment is performed. Such a guide may be coupled to alignment guide <NUM> by inserting a dovetail extension into the corresponding dovetail/undercuts provided by rails <NUM>, <NUM> of housing <NUM>. The cutting or drill guide may be locked to the housing <NUM> by rotating locking screw <NUM> in a first direction (e.g., counter-clockwise). The unlocking is provided by the ball head <NUM> engaging the surface(s) defining cavity <NUM> of locking block <NUM>, which causes locking block <NUM> to be pulled inwardly into chamber <NUM> guided by the engagement of pins <NUM> and slots <NUM> decoupling alignment guide <NUM> from the cutting and/or drill guide. Rotating the locking screw <NUM> in a second, opposite direction (e.g., clockwise) results in the locking of the cutting and/or drill guide from alignment guide <NUM>, such that the alignment guide <NUM> may be coupled to the cutting and/or drill guide. For example, the dovetail connection between the alignment guide <NUM> and the cutting and/or drill guide may be engaged by sliding the alignment guide <NUM> relative to the cutting and/or drill guide.

The swing arm <NUM> may be locked in position relative to the bone of the patient by inserting pins or wires through holes <NUM> defined by swing arm <NUM> (and thus also through slots <NUM> defined by base <NUM>). With swing arm <NUM> pinned to the patient's bone, one or more pins may be removed from the holes <NUM> defined by wings <NUM> of base <NUM> so that base <NUM> may be repositioned (e.g., such that the elongate body <NUM> of base <NUM> is parallel to elongate body <NUM> of swing arm <NUM>).

If desired, an elongate radiopaque member, such as a k-wire or pin, may be inserted through hole <NUM> defined by pin holder <NUM> to provide for a fluoroscopic check. Under fluoroscopy, a surgeon or other individual may check to determine whether the radiopaque member <NUM> is aligned with a mechanical and/or longitudinal axis defined by a bone, such as the tibia, of the patient. A person of ordinary skill in the art will understand that the fluoroscopic check may be performed before or after the cutting and/or drill guide is coupled to the alignment guide <NUM>.

Claim 1:
A surgical alignment guide (<NUM>; <NUM>; <NUM>), comprising:
a base (<NUM>; <NUM>; <NUM>), the base defining at least one first hole (<NUM>-<NUM>, <NUM>-<NUM>; <NUM>-<NUM>, <NUM>-<NUM>; <NUM>-<NUM>) sized and configured to receive a first fixation element (<NUM>) and defining at least one second hole (<NUM>-<NUM>, <NUM>-<NUM>; <NUM>-<NUM>, <NUM>-<NUM>; <NUM>-<NUM>) sized and configured to receive a second fixation element (<NUM>); and
a swing arm (<NUM>; <NUM>; <NUM>) for coupling to the base such that the swing arm is rotatably movable relative to the base, the swing arm extending from a first end (<NUM>; <NUM>; <NUM>) to a second end (<NUM>), the second end of the swing arm including a coupling mechanism for coupling another guide (<NUM>) to the second end of the swing arm; and
a locking device (<NUM>; <NUM>; <NUM>) for selectively fixing a position of the swing arm relative to the base,
wherein the base (<NUM>; <NUM>) supports a spring-loaded detent (<NUM>; <NUM>) that is configured to engage a plurality of teeth (<NUM>; <NUM>) located at the first end (<NUM>; <NUM>) of the swing arm (<NUM>; <NUM>) so as to provide at least one of an audible or a tactile indication when the swing arm is rotatably moved relative to the base.