Surgical Clamp Assembly For Fixing A Navigation Tracker To A Portion Of Bone

A surgical clamp assembly for clamping tissue and supporting a navigation tracker. The assembly includes a clamp body. Clamp arms are coupled to the clamp body to grip tissue. At least one of the clamp arms includes a distal portion having a clamp surface to grip tissue and a proximal portion that is pivotable relative to the clamp body about a first pivot. A linear displacement mechanism and a carrier are coupled to the clamp body. The carrier is moveable relative to the clamp body along a carrier axis in response to movement of the linear displacement mechanism. The carrier is coupled directly to the proximal portion of the clamp arm. The clamp arm is also pivotable relative to the carrier about a second pivot in response to movement of the carrier.

BACKGROUND

Surgical navigation systems assist users in locating surgical objects in the operating room. The navigation system includes a localizer that can use any type of sensing modality to determine the position and/or orientation of tracking devices attached to the surgical objects. The surgical objects are often instruments, devices, or an anatomic object, such as bone.

Attaching the tracking device to a bone has historically required securing a screw, plate, or other fastener to the bone to provide a rigid frame for the tracking device relative to the bone. However, such fastening techniques are undesirable as they require invasively drilling fasteners into the bone. Moreover, because these fastening techniques require drilling into the bone, the surgeon is often prevented from easily adjusting the setup of the tracking device. For example, the surgeon may need to relocate the tracking device due to the size of the patient or incision at the surgical site, etc.

Other attachment mechanisms have included clamps that secure to the bone.

However, conventional bone clamps have been limited in the amount of force they can exert on the bone. In turn, the lack of clamping force may comprise the rigid connection to the bone and cause loss of tracking accuracy or loss of tracking altogether. Furthermore, certain procedures, like joint arthroplasty, involve long bones, such as the femur and humerus, which significantly vary in size from patient to patient. Yet, the range of motion of the jaws of a conventional bone clamp is limited. In turn, the reduced range of motion limits the size of bones that can fit between the jaws of the conventional bone clamp. Additionally, conventional bone clamps present a relatively large footprint, which may not be conducive for procedures having limited access angle or incision size. Moreover, the mechanisms or techniques involved with closing and opening the jaws of conventional bone clamps are often not ergonomic or user friendly and may increase the risk of collisions at the surgical site.

SUMMARY

This Summary introduces a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to limit the scope of the claimed subject matter nor identify key features or essential features of the claimed subject matter.

According to a first aspect, a surgical clamp assembly for clamping tissue and supporting a navigation tracker is provided. The surgical clamp assembly comprises a clamp body. A first clamp arm is coupled to the clamp body. A second clamp arm is coupled to the clamp body and configured to grip tissue with the first clamp arm. The second clamp arm comprises a distal portion having a clamp surface. The second clamp arm comprises a proximal portion pivotable relative to the clamp body about a first pivot. A linear displacement mechanism is coupled to the clamp body. A carrier is coupled to the linear displacement mechanism. The carrier is moveable relative to the clamp body along a carrier axis in response to movement of the linear displacement mechanism. The carrier is coupled directly to the proximal portion of the second clamp arm. The proximal portion of the second clamp arm is pivotable relative to the carrier about a second pivot in response to movement of the carrier.

According to a second aspect, a surgical attachment system for fixing a navigation tracker to a portion of bone is provided. The surgical attachment system comprises an extension arm configured to support the navigation tracker. The surgical attachment system further comprises a surgical clamp assembly configured to support the extension arm. The surgical clamp assembly comprises a clamp body. A first clamp arm is coupled to the clamp body. A second clamp arm is coupled to the clamp body and configured to grip tissue with the first clamp arm. The second clamp arm comprises a distal portion having a clamp surface. The second clamp arm comprises a proximal portion pivotable relative to the clamp body about a first pivot. A linear displacement mechanism is coupled to the clamp body. A carrier is coupled to the linear displacement mechanism. The carrier is moveable relative to the clamp body along a carrier axis in response to movement of the linear displacement mechanism. The carrier is coupled directly to the proximal portion of the second clamp arm. The proximal portion of the second clamp arm is pivotable relative to the carrier about a second pivot in response to movement of the carrier.

According to a third aspect, a surgical tracking system is provided. The surgical tracking system comprises a navigation tracker. The surgical tracking system further comprises a surgical attachment system for fixing the navigation tracker to a portion of bone. The surgical attachment system comprises an extension arm configured to support the navigation tracker. The surgical attachment system further comprises a surgical clamp assembly configured to support the extension arm. The surgical clamp assembly comprises a clamp body. A first clamp arm is coupled to the clamp body. A second clamp arm is coupled to the clamp body and configured to grip tissue with the first clamp arm. The second clamp arm comprises a distal portion having a clamp surface. The second clamp arm comprises a proximal portion pivotable relative to the clamp body about a first pivot. A linear displacement mechanism is coupled to the clamp body. A carrier is coupled to the linear displacement mechanism. The carrier is moveable relative to the clamp body along a carrier axis in response to movement of the linear displacement mechanism. The carrier is coupled directly to the proximal portion of the second clamp arm. The proximal portion of the second clamp arm is pivotable relative to the carrier about a second pivot in response to movement of the carrier.

According to a fourth aspect, a navigation system is provided which includes a localizer for tracking the navigation tracker attached to the surgical attachment system of the third aspect.

Any of the above aspects can be utilized individually, or in combination.

Any of the above aspects can be utilized with any of the following implementations:

In one implementation the first pivot is fixed relative to the clamp body and the proximal portion of the second clamp arm such that the second clamp arm is pivotable relative to the clamp body. In one implementation the second pivot is fixed relative to the proximal portion of the second clamp arm and moveable relative to the carrier such that the second clamp arm is pivotable and translatable relative to the carrier.

In one implementation a retainer is disposed at the second pivot and the retainer is coupled to the proximal portion of the second clamp arm and the carrier and the carrier defines a slot to receive the retainer. In one implementation the slot is sized to permit the retainer to rotate and translate within the slot. In one implementation the slot is sized to permit the retainer to move along a respective slot axis that is perpendicular to the carrier axis. In one implementation the carrier comprises opposing slot walls of the slot that defines a height of the slot and the carrier comprises opposing slot ends defining a width of the slot and the height of the slot approximates a height of the retainer. In one implementation the width of the slot is greater than the height of the slot.

In one implementation the linear displacement mechanism comprises a linearly translatable lead screw. In one implementation the second clamp arm comprises an arm grip on the clamp surface and the clamp body comprises a body grip and the arm grip and the body grip are configured to grip tissue. In one implementation the clamp body comprises a stationary portion that remains stationary while the second clamp arm moves about the first pivot and the stationary portion comprises a distal-facing surface and a grip extending distally from the distal-facing surface. In one implementation the grip and the stationary portion of the clamp body are monolithic in construction.

In one implementation the linear displacement mechanism is engageable with the carrier such that the carrier is moveable along the carrier axis in response to rotation of the linear displacement mechanism. In one implementation the linear displacement mechanism is threadably engageable with the carrier. In one implementation the clamp body defines a channel to receive the carrier and permit the carrier to move along the carrier axis. In one implementation the carrier axis is centered in the channel. In one implementation the clamp body defines a notch further defining the channel and the notch is configured to at least partially receive the second clamp arm to permit the second clamp arm to pivot about the first pivot with a greater range.

In one implementation the clamp body comprises an attachment interface for detachable coupling to an extension arm. In one implementation the attachment interface is oriented transverse to the carrier axis. In one implementation the first pivot is disposed at a first distance from the carrier axis and the second pivot is disposed at a second distance from the carrier axis less than the first distance. In one implementation the first clamp arm is fixed to the clamp body. In one implementation the first clamp arm is pivotable relative to the clamp body and the carrier and configured to move in concert with the second clamp arm. In one implementation the first clamp arm is symmetrical of the second clamp arm about a reference plane extending through the carrier axis. In one implementation, the clamp body is integrally coupled to the extension arm.

In one implementation a connector is coupled to the extension arm for coupling to the navigation tracker and first and second tracker rotational adjusters disposed between the extension arm and the connector and the first tracker rotational adjuster is configured to selectively rotate the connector relative to the first end of the extension arm about a first connector axis and the second tracker rotational adjuster is configured to selectively rotate the connector about a second connector axis perpendicular to the first connector axis.

In one implementation the first and second tracker rotational adjusters each comprise a pair of opposing lock teeth, with the pair of opposing lock teeth configured to rotate relative to one another when spaced apart and rotatably lock when in engagement with one another. In one implementation an extension arm rotational adjuster is configured to selectively rotate the second end of the extension arm relative to the clamp body about an arm axis. In one implementation arm axis is transverse to the carrier axis. In one implementation the extension arm rotational adjuster and the clamp body each comprise lock teeth opposing each other and the lock teeth on the extension arm rotational adjuster and the lock teeth on the clamp body are configured to rotate relative to each other when spaced apart and rotatably lock when in engagement with each other. In one implementation, the tissue is a bone, such as a long bone, including but not limited to a femur, tibia, or humerus.

DETAILED DESCRIPTION

I. Example Surgical System

Referring to the Figures, wherein like numerals indicate like or corresponding parts throughout the several views, an example of a surgical system10(hereinafter “system”) is shown throughout.

As shown inFIG.1, the system10may treat an anatomy (surgical site) of a patient12, such as bone or soft tissue. InFIG.1, the patient12is undergoing a surgical procedure. The anatomy inFIG.1includes a humerus (H) of the patient12. The surgical procedure may involve tissue removal or treatment. Treatment may include cutting, coagulating, lesioning the tissue, treatment in place of tissue, or the like. In one example, the surgical procedure is a shoulder joint procedure, such as reverse shoulder arthroplasty, anatomical shoulder arthroplasty, shoulder revision surgery, or the like. Alternatively, the surgical procedure may be a partial or total knee or hip replacement surgery. In one example, the system10is designed to cut away material to be replaced by surgical implants, such as glenoid implants, humeral implants, hip and knee implants, including unicompartmental, bicompartmental, multicompartmental, or total knee implants. The implants used with the techniques described here can be like that disclosed in U.S. Pat. No. 9,937,058, entitled, “Prosthetic Implant and Method of Implantation,” and U.S. Pat. No. 11,432,945, entitled “Robotic System For Shoulder Arthroplasty Using Stemless Implant Components”, the entire disclosure of each of these patents being hereby incorporated by reference. The system10disclosed herein may be used to perform other procedures, surgical or non-surgical, or may be used in industrial applications or other applications where robotic systems are utilized.

The system10may include a robotic manipulator14. The robotic manipulator14has a base16and plurality of links18. A manipulator cart17supports the robotic manipulator14such that the robotic manipulator14is fixed to the manipulator cart17. The links18collectively form one or more arms of the robotic manipulator14. The robotic manipulator14may have a serial arm configuration (as shown inFIG.1) or a parallel arm configuration. In other examples, more than one robotic manipulator14may be utilized in a multiple arm configuration. The robotic manipulator14may comprise a plurality of (prismatic and/or rotating) joints (J) and a plurality of motor and/or joint encoders19located at the joints (J) for determining position data of the joints (J). For simplicity, only one joint encoder19is illustrated inFIG.1, although it is to be appreciated that the other joint encoders19may be similarly illustrated. The robotic manipulator14according to one example has six joints (J1-J6) implementing at least six-degrees of freedom (DOF) for the robotic manipulator14. However, the robotic manipulator14may have any number of degrees of freedom and may have any suitable number of joints (J) and redundant joints (J).

A surgical tool20(hereinafter “tool”) couples to the robotic manipulator14and is movable relative to the base16to interact with the anatomy in certain modes. The tool20is or can form part of an end effector22. The tool20may be grasped by the operator. One exemplary arrangement of the robotic manipulator14and the tool20is described in U.S. Pat. No. 9,119,655, entitled, “Surgical Manipulator Capable of Controlling a Surgical Instrument in Multiple Modes,” the disclosure of which is hereby incorporated by reference. The robotic manipulator14and the tool20may be arranged in alternative configurations. The tool20can be like that shown in U.S. Pat. No. 9,566,121, filed on Mar. 15, 2014, entitled, “End Effector of a Surgical Robotic Manipulator,” hereby incorporated by reference.

The positioning of the end effector22and the tool20is defined by the robotic manipulator14. The tool20includes an energy applicator24designed to contact the target site, such as the tissue of the patient12at the surgical site. The energy applicator24may be a drill, a saw blade, a bur, an ultrasonic vibrating tip, or the like.

The system10includes a controller30. The controller30includes software and/or hardware for controlling the robotic manipulator14. The controller30directs the motion of the robotic manipulator14and controls a state (position and/or orientation) of the tool20with respect to a coordinate system of the manipulator14.

As shown inFIG.1, the system10further includes a surgical navigation system32. The navigation system32may be utilized with any surgical setup and is not required to be utilized with the robotic manipulator14. The surgical navigation system32is configured to track movement of various objects. Such objects include, for example, the robotic manipulator14, the tool20, or any other surgical tool, such as a probe, and the anatomy, e.g., humerus H.

The surgical navigation system32may include a cart assembly34that houses a navigation computer36, and/or other types of control units. A navigation interface may be in operative communication with the navigation computer36. The navigation interface includes one or more displays38. First and second input devices40,42may be used to input information into the navigation computer36or otherwise to select/control certain aspects of the navigation computer36. As shown inFIG.1, such input devices40,42include interactive touchscreen displays. However, the input devices40,42may include any one or more of a keyboard, a mouse, a microphone (voice-activation), gesture control devices, and the like. The controller30may be implemented on any suitable device or devices in the system10, including, but not limited to, the manipulator computer26, the navigation computer36, and any combination thereof.

The surgical navigation system32also includes a navigation localizer44(hereinafter “localizer”) coupled to the navigation computer36. The surgical navigation system32utilizes the localizer44to track surgical objects and gather state information of each object with respect to a (navigation) localizer coordinate system LCLZ. Coordinates in the localizer coordinate system LCLZ may be transformed to the manipulator coordinate system MNPL, and/or vice-versa, using transformation techniques described herein.

In one example, the localizer44is an optical localizer and includes a camera unit46. The camera unit46has an outer casing48that houses one or more optical sensors50.

The surgical navigation system32may include one or more trackers. In one example, the trackers include a pointer tracker PT, one or more manipulator trackers52, and one or more patient trackers54. In the illustrated example ofFIG.1, the pointer tracker PT is firmly affixed to a pointer P used for registering the anatomy to the localizer coordinate system LCLZ. A manipulator tracker52is firmly attached to the tool20(i.e., tracker52A). The manipulator tracker52may be affixed to any suitable component of the robotic manipulator14, in addition to, or other than the tool20, such as the base16(i.e., tracker52B), or any one or more links18of the robotic manipulator14. In the example shown, the patient tracker54is firmly affixed to a bone, such as the humerus H of the patient12. Of course, depending on the procedure, the patient tracker54could alternatively be affixed to any other type of anatomy or bone. Additionally, the tracker54may be affixed on left or right sides of the patient anatomy. Systems, assemblies, and techniques involving securing the patent tracker to the anatomy are described in the section below.

Any one or more of the trackers may include active markers58. The active markers58may include light emitting diodes (LEDs). Alternatively, the trackers52,54may have passive markers, such as reflectors, which reflect light emitted from the camera unit46. Other suitable markers not specifically described herein may be utilized.

The localizer44tracks the trackers52,54to determine a state of each of the trackers52,54which correspond respectively to the state of the object respectively attached thereto. The localizer44provides the state of the trackers52,54to the navigation computer36. In one example, the navigation computer36determines and communicates the state the trackers52,54to the manipulator computer26. As used herein, the state of an object includes, but is not limited to, data that defines the position and/or orientation of the tracked object or equivalents/derivatives of the position and/or orientation. For example, the state may be a pose of the object, and may include linear data, and/or angular velocity data, and the like.

Although one example of the surgical navigation system32is shown in the Figures, the surgical navigation system32may have any other suitable configuration for tracking the robotic manipulator14and the patient12. In one example, the surgical navigation system32and/or localizer44are ultrasound-based. In another example, the surgical navigation system32and/or localizer44are radio frequency (RF)-based. In another example, the surgical navigation system32and/or localizer44are machine-vision based. The navigation system32can utilized any combination of these modalities. The surgical navigation system32can include any aspects of the navigation systems described in U.S. Pat. No. 9,008,757 entitled, “Navigation System Including Optical and Non-Optical Sensors,” or U.S. Pat. No. 9,603,665 entitled “System And Methods For Establishing Virtual Constraint Boundaries”, the entire contents of each of these patents being hereby incorporated by reference.

The surgical navigation system32and/or localizer44may have any other suitable components or structure not specifically recited herein. Furthermore, any of the techniques, methods, and/or components described above with respect to the camera-based surgical navigation system32shown throughout the Figures may be implemented or provided for any of the other examples of the surgical navigation system32described herein. For example, the surgical navigation system32may utilize solely inertial tracking or any combination of tracking techniques.

The controller30further includes software modules. The software modules may be part of a computer program or programs that operate on the manipulator computer26, navigation computer36, or a combination thereof, to process data to assist with control of the system10. The software modules include instructions stored in memory on the manipulator computer26, navigation computer36, or a combination thereof, to be executed by one or more processors of the computers26,36. Additionally, software modules for prompting and/or communicating with the operator may form part of the program or programs and may include instructions stored in memory on the manipulator computer26, navigation computer36, or a combination thereof. The operator interacts with the first and second input devices40,42and the one or more displays38to communicate with the software modules. The user interface software may run on a separate device from the manipulator computer26and navigation computer36.

The controller30includes a manipulator controller60for processing data to direct motion of the robotic manipulator14. In one example, as shown inFIG.1, the manipulator controller is implemented on the manipulator computer26. The manipulator controller60may receive and process data from a single source or multiple sources. The controller30further includes a navigation controller62for communicating the state data relating to the bone, e.g., humerus H or scapula, and robotic manipulator14to the manipulator controller60. The manipulator controller60receives and processes the state data provided by the navigation controller62to direct movement of the robotic manipulator14. In one example, as shown inFIG.1, the navigation controller62is implemented on the navigation computer36. The manipulator controller60or navigation controller62may also communicate states of the patient12and robotic manipulator14to the operator by displaying an image of the humerus H and/or scapula and the robotic manipulator14on the one or more displays38. The manipulator computer26or navigation computer36may also command display of instructions or request information using the display38to interact with the operator and for directing the robotic manipulator14.

The robotic system shown inFIG.1is provided only as one possible example of a system that can be utilized with the clamping and attachment system described in the next section. The clamping and attachment system can be utilized with any type of navigated surgical system, such as one including manual hand-held tools, robotic hand-held tools, imaging systems (e.g., CT, X-ray, C-arms, etc.), or and for any type of navigated orthopedic or non-orthopedic procedure.

II. Surgical Clamping and Attachment System

Described in this section are surgical clamping and attachment systems that can be utilized with a navigation tracker54, such as that shown inFIG.1. The navigation tracker54is utilized as the patient tracker described above, with the navigation computer36determining the state of the navigation tracker54to track the patient12. The navigation tracker54can have various configurations depending on the tracking modalities described above.

As shown inFIG.2, the surgical navigation system32further comprises a surgical attachment system106for fixing the navigation tracker54to a portion of bone. As will become apparent from description below, the surgical attachment system106is configured to be selectively connected to and disconnected from the bone. In one example, the bone is the humerus H subject to a shoulder surgery. However, the surgical attachment system106may be configured to be fixed to any suitable bone, such as a scapula, femur, tibia, pelvis, or any part of the spinal bone (vertebra or spinous process).

The surgical attachment system106may include an extension arm108with a first end110and a second end112. The extension arm108may have a substantially cylindrical configuration. In other configurations, the extension arm108may be configured as a bent rod or a curved cylinder. However, the extension arm108may have any suitable configuration for supporting the navigation tracker54at a position spaced from the patient12. The extension arm108can have any suitable length to enable the navigation tracker54to be exposed relative to the surgical site, and hence, trackable by the navigation system32. One example of an extension arm108that can be utilized with the navigation system32and other portions of the attachment system106is disclosed in commonly owned U.S. patent application Ser. No. 17,673,055, published as U.S. Patent Publication No. 2022/0257334, entitled “Clamp Assembly for Fixing a Navigation Tracker to a Portion of Bone” the entire disclosure of which is hereby incorporated by reference.

The attachment system106may comprise a first extension attachment interface114disposed at the first end110of the extension arm108. The first extension attachment interface114may be configured to detachably couple to the navigation tracker54. In other configurations, the extension arm108may be coupled to the navigation tracker54such that the extension arm108and the navigation tracker54are not detachable. In other words, the extension arm108may be rigidly attached to the navigation tracker54. In such a configuration, the extension arm108may still be configured to be selectively rotatably relative to the navigation tracker54. In still other configurations, the extension arm108may be integral with the navigation tracker54. A second extension attachment interface115may be disposed at the second end112of the extension arm108. The second extension attachment interface115may be configured for detachable coupling to a clamp assembly126, as described in greater detail below. The first extension attachment interface114may comprise a connector116for coupling to the navigation tracker54and first and second tracker rotational adjusters118,120disposed between the extension arm108and the connector116.

The connector116may be configured as a quick-connect coupler. More specifically, the quick-connect coupler corresponds with a connector on the navigation tracker54. Coupling the navigation tracker54to the quick-connect coupler may be performed by pushing the connector of the navigation tracker54onto the quick-connect coupler until the connector no longer moves on the quick-connector coupler. The connector on the navigation tracker54may be actuated (e.g., by sliding a collar) to remove the navigation tracker54from the first extension attachment interface114. Although the connector116of the first extension attachment interface114is shown as a quick-connect coupler, the connector116may be configured in any other suitable configuration for coupling the navigation tracker54to the first extension attachment interface (e.g., threaded engagement). The connector116may provide a kinematic coupling to the navigation tracker54. One example of such quick-connect couplers for a navigation tracker54is disclosed in U.S. Pat. No. 10,537,395, entitled “Navigation Tracker with Kinematic Connector Assembly” the entire disclosure of which is hereby incorporated by reference.

The first tracker rotational adjuster118may be configured to selectively rotate the connector116relative to the first end110of the extension arm108about a first connector axis. The second tracker rotational adjuster112may be configured to selectively rotate the connector116about a second connector axis that is perpendicular to the first connector axis. Said differently, the first and second tracker rotational adjusters118,120enable the selective adjustment of the navigation tracker54about two degrees of freedom. Furthermore, the first and second tracker rotational adjusters118,120are configured to selectively maintain the navigation tracker54in a desired position for allowing the navigation computer36to determine and communicate the state of the navigation tracker54to the manipulator computer26(i.e., by locking the first and second rotational adjusters118,120and preventing rotation about the arm and connector axes).

The first and second tracker rotational adjusters118,120may each comprise a pair of opposing lock teeth, with the pair of opposing lock teeth configured to rotate relative to one another when spaced apart and rotatably lock when in engagement with one another. The first extension attachment interface114may further comprise a knob124. The knob124may be operably coupled to each of the first and second rotational adjusters118,120. More specifically, rotating the knob124may change the spacing between the opposing lock teeth. For example, rotating the knob124in a counter-clockwise direction (i.e., loosening the knob) moves apart the opposing lock teeth of each of the first and second rotational adjusters118,120. When the opposing lock teeth are spaced sufficiently apart, the teeth may rotate relative to one another about the respective arm and connector axes thus allowing the rotation of the first and second rotational adjusters118,120about the axes. On the other hand, rotating the knob124in a clockwise direction (i.e., tightening the knob) may move together the opposing lock teeth of each of the first and second tracker rotational adjusters. When the opposing lock teeth contact one another (with opposing lock teeth alternating side-by-side about the respective arm and connector axes), the teeth may not rotate relative to one another about respective arm and connector axes thus locking rotation of the first and second tracker rotational adjusters118,120about the connector axes.

The second extension attachment interface115may comprise an extension arm rotational adjuster119similar to the tracker rotational adjusters118,120. The extension arm rotational adjuster119may be configured to selectively rotate the second end112of the extension arm108relative to a clamp body128of the clamp assembly126about an arm axis EX. The extension arm rotational adjuster119may be configured to be threadably coupled to the clamp body126to secure the extension arm108to the clamp assembly126. The extension arm rotation adjuster119may be configured to be rotated by a powered hand tool or a non-powered (manually driven) hand tool. In another configuration, the extension arm rotational adjuster119may comprise a knob, dial, or other similar shape to be graspable by a user and facilitate coupling. Other couplers are contemplated. For instance, the extension arm rotational adjuster119may comprise a post that is received by the clamp body126and a clamp (not shown) may be manipulated by the user to secure the post to the clamp body126.

One example of the first and second extension attachment interfaces114,115are shown in the Figures. However, the first and second extension attachment interfaces114,115may utilize any suitable configuration for allowing selective rotation of the navigation interface about the connector axes and the extension arm108about the arm axis EX.

In other configurations, the extension arm108may be coupled to the clamp body126of the clamp assembly112such that the extension arm108and the clamp body126are not detachable. In other words, the extension arm108may be rigidly attached to the navigation tracker clamp body126. In such a configuration, the extension arm108may still be configured to be selectively rotatably relative to the clamp body126. In still other configurations, the extension arm108may be integral with the clamp body126.

As shown inFIGS.1and3, the surgical attachment system106includes a surgical clamp assembly126disposed at the second end112of the extension arm108for clamping tissue and fixing the navigation tracker54to the portion of the bone. The surgical clamp assembly126includes a clamp body128. First and second clamp arms130a,130bare coupled to the clamp body128and configured to grip tissue adjacent the clamp body128. In some configurations, one of the first and second clamp arms130a,130bis fixed to the clamp body128. In such a configuration, the fixed clamp arm and the clamp body128may comprise a single body such that the clamp body128and the fixed clamp arm are monolithic in construction. In another configuration, one of the clamp arms130a,130bmay be coupled to the clamp body128in any suitable manner, including welding, chemical adhesion, and mechanical fastening. In still other configurations, both the first and second clamp arms130,132are pivotably coupled to the clamp body128.

As shown in the example ofFIGS.5and6, the first and second clamp arms130a,130bare each pivotably coupled to the clamp body128. The clamp arms130a,130bmay each include a distal portion132a,132bhaving a clamp surface134a,134band a proximal portion136a,136bthat is pivotable relative to the clamp body128about a first pivot138a,138b. The clamp surfaces134a,134bmay be configured to face each other when the clamp arms130a,130bgrip tissue. Features of the clamp arms130a,130band connections between the clamp arms130a,130band the clamp body128are described below to be identical. However, it is contemplated that one or more features from the first clamp arm130aand/or connections of the first clamp arm130ato the clamp body128may be different than features from the second clamp arm130band/or connections of the second clamp arm130bto the clamp body128. Furthermore, while features of the first clamp arm130aand connections between the first clamp arm130aand the clamp body128may be described below, it is appreciated that the identical or similar features may be employed with the second clamp arm130b.

The surgical clamp assembly126also includes a linear displacement mechanism140coupled to the clamp body128and configured to move the clamp arms130a,130b. A carrier142is coupled to the linear displacement mechanism140. The carrier142is moveable relative to the clamp body128along a carrier axis CX in response to movement of the linear displacement mechanism140. The carrier axis CX may be transverse to the arm axis EX. The carrier142is coupled directly to the proximal portions136a,136bof each of the clamp arms130a,130b. In other words, there are no intermediate linkages connected between the carrier142and the clamp arms130a,130b. The proximal portions136a,136bof the clamp arms130a,130bare pivotable relative to the carrier142about respective second pivots144a,144bin response to movement of the carrier142. The surgical clamp assembly126may comprise biasing members such as springs that bias the distal portions132a,132bof the clamp arms130a,130b. In some configurations, the distal portions132a,132bof the clamp arms130a,130bmay be biased together. In other configurations, the distal portions132a,132bof the clamp arms130a,130bmay be biased apart.

In many configurations, the tissue being gripped (e.g., a portion of the humerus) may have non-parallel surfaces to be gripped by the clamp arms130a,130b. The distal portions132a,132bmay be formed such that the clamping surfaces134a,134bare not parallel to each other to accommodate such non-parallel surfaces. In other configurations, the distal portions132a,132bmay comprise multiple sections that pivotable relative to each other to clamp a large range of non-parallel surfaces.

In the configurations illustrated inFIGS.5and6, the clamp arms130a,130b, the carrier142, the first pivots138a,138b, and the second pivots144a,144bare symmetrical across a reference plane that extends through the carrier axis CX. Said differently, the clamp arms130a,130b, the carrier142, the first pivots138a,138b, and the second pivots144a,144bare symmetrical across the carrier axis CX when viewed from the side as shown inFIGS.5and6. In other configurations, one or more of the clamp arms130a,130b, the carrier142, the first pivots138a,138b, and the second pivots144a,144bare symmetrical across a reference plane while one or more of the clamp arms130a,130b, the carrier142, the first pivots138a,138b, and the second pivots144a,144bare not symmetrical across a reference plane. In another configuration, where the clamp arms130a,130b, the carrier142, the first pivots138a,138b, and the second pivots144a,144bare not each symmetrical across a reference plane, the first clamp arm130amay still be pivotable relative to the clamp body128and the carrier142such that the first clamp arm130ais configured to move in concert with the second clamp arm130b.

The first pivot138amay be disposed at a first distance from the carrier axis CX and the second pivot144ais disposed at a second distance from the carrier axis CX less than the first distance. As described in greater detail below, the second pivot144amay be configured to be translatable relative to the carrier142such that the distance between the second pivot144aand the carrier axis CX may change based on pivoting of the clamp arm130aabout the first pivot138a. In some configurations, the first pivot138ais always closer to the carrier axis CX than the second pivot144ais to the carrier axis CX in any position of the first clamp arm130a. The first and second pivots138a,144amay be disposed at a third distance relative to each other greater than the second distance.

The first pivot138amay be fixed relative to the clamp body128and the proximal portion136aof the clamp arm130asuch that the clamp arm130ais pivotable relative to the clamp body128. In other words, the first pivot138amay comprise a first pivot axis FX that is fixed relative to the clamp body128and the proximal portion136aof the clamp arm130amay pivot relative to the clamp body128about the first pivot axis FX. A first pivot retainer may be disposed at the first pivot138ato constrain movement between the clamp arm130aand the clamp body128. In the illustrated configurations, the first pivot retainer comprises a cylindrical body, e.g., a pin. In other configurations, the first pivot retainer may comprise a partially spherical protrusion. In still other configurations, the first pivot retainer may comprise another shape that is capable of facilitating pivoting of the proximal portion136aof the clamp arm130arelative to the clamp body128while preventing translation of the proximal portion136aof the clamp arm130afrom translating relative to the clamp body128.

As shown in one configuration illustrated inFIGS.5-7, the linear displacement mechanism140may be threadably engageable with a bore148of the carrier142. The linear displacement mechanism140may be engageable with the carrier142such that the carrier142is moveable along the carrier axis CX in response to rotation of the linear displacement mechanism140. In the illustrated configuration, the linear displacement mechanism140comprises a threaded member such as a linearly translatable lead screw. The lead screw140may be rotatably coupled to the clamp body128and constrained from moving in an axial direction by one or more holders150that are coupled to the clamp body128. The lead screw140may be rotatable about a driver axis DX. The driver axis DX may be parallel to the carrier axis CX. In some configurations, the driver axis DX may be colinear with carrier axis CX. In some configurations where the carrier axis CX is used as a reference for relative movement or position and the driver axis DX is colinear with the carrier axis CX, it is contemplated that the same relative movement or position may apply with reference to the driver axis DX.

The linear displacement mechanism140may comprise a drive head152configured to be rotated by a user for actuating the linear displacement mechanism140. In one configuration, rotation of the drive head152causes movement of the carrier142relative to the clamp body128and thus, rotation of the proximal portion136aof the clamp arm130arelative to the clamp body128. The drive head152may be configured as a square head that can be driven by a corresponding driver bit. However, the drive head152may be any suitable size and shape. Furthermore, the driver head152can be coupled to a powered hand tool or a non-powered (manually driven) hand tool.

The drive head152may be disposed in a bore154of the clamp body128such that none of the drive head152protrudes outside of the clamp body128. In such a configuration, a cap (not shown) may be removably coupled over the bore154to cover the bore154and seal the drive head152inside the clamp body128. In other configurations, the linear displacement mechanism140may comprise a knob that may be gripped and rotated by a user to effect rotation.

Each holder150may comprise a pin or another body configured to axially secure the lead screw to the clamp body128while permitting the lead screw140to rotate relative to the clamp body128. As the lead screw140is threadably engaged with the carrier142and not with the clamp body128, rotation of the lead screw140causes the carrier142to move axially relative to the clamp body128and the lead screw140. Axial movement the carrier142results in one or both the clamp arms130a,130bto pivot relative to the clamp body128about the first pivots138a,138b. In some configurations, the clamp body128may comprise one or both the holders150.

In other configurations, the relationship between the carrier142and the clamp body128may be reversed. Specifically, the lead screw140may be threadably engageable with the clamp body128and the lead screw140may be rotatably coupled to the carrier142and constrained from moving in an axial direction by one or more holders150that are coupled to the carrier142. Each holder150would axially secure the lead screw140to the carrier142while permitting the lead screw140to rotate relative to the carrier142. As the lead screw140is threadably engaged with the clamp body128and not with the carrier142, rotation of the lead screw140may cause the carrier142to move axially relative to the clamp body128. In this configuration, the lead screw140would move with the carrier142relative to the clamp body128.

In another configuration, a threaded nut (not shown) may be used to move the carrier142axially relative to the clamp body128. In this configuration, the lead screw140may be fixed relative to the clamp body128. The lead screw140may extend within a through hole of the carrier142and the threaded nut may be threadably engaged with the lead screw140such that rotation of the threaded nut causes the threaded nut and the carrier142to axially translate relative to the lead screw140and the clamp body128.

In alternative configurations, the linear displacement mechanism140may comprise a linear actuator or another device used to provide linear motion of the carrier relative to the clamp body128to pivot the first and second clamp arms130a,130b.

The second pivot144amay comprise a second pivot retainer. The second pivot144amay be fixed relative to the proximal portion136aof the clamp arm130aand moveable relative to the carrier142such that the second pivot144aand thus the clamp arm130a, are pivotable and translatable relative to the carrier142. The carrier142may define a slot158ato receive the second pivot retainer. The slot158amay be sized to permit the second pivot retainer to rotate and translate within the slot158a. In some configurations, the slot158ais open at one end. The slot158amay be sized to permit the second pivot retainer to move in a direction that is perpendicular to the carrier axis CX. The carrier142may comprise opposing slot walls of the slot158athat define a height of the slot158a. The carrier142may comprise opposing slot ends defining a width of the slot158a. The height of the slot158amay approximate a height of the second pivot retainer such that the second pivot144amay only translate linearly within the slot158a. The width of the slot158amay be greater than the height of the slot158a. In other configurations the proximal portion136aof the clamp arm130adefines the slot158aand the second pivot144ais fixed to the carrier142. Such a configuration would still permit pivoting and translation of the clamp arm130arelative to the carrier142.

The clamp arms130a,130bmay each comprise an arm grip160a,160bon the clamp surface134a,134b. The clamp body128may comprise a body grip162. The arm grip160a,160band the body grip162are configured to grip tissue. The arm grip160a,160band body grip162may comprise projections for piercing into and gripping the bone. The projections may be disposed at non-orthogonal angles relative to the surface they project from. The projections may comprise teeth. The teeth may have a conical configuration. However, the projections may have any suitable configuration for gripping the bone.

In other configurations, the arm grip160a,160bmay be disposed on a floating platform coupled to the clamp arm130a. The floating platform may be pivotable, swivelable, or otherwise moveably coupled to the clamp arm130awhen not in contact with tissue. When a user operates the linear displacement mechanism to grip the tissue with the clamp arms130a,130b, the force acting on the clamp arms130a,130band the tissue may cause the floating platforms to first move to a position that conforms the arm grips160a,160bto the tissue and then remain in place.

In other configurations, the arm grip160a,160band the body grip162may each have configurations other than teeth configured to fix the clamp assembly126to the bone. For example, the arm grip160a,160band the body grip162may have an abrasive texture that increases the coefficient of friction between the bone and the arm grip160a,160band the body grip162when in contact with the bone. The arm grip160a,160band body grip162may have any suitable configuration for fixing the clamp assembly126to the bone.

The clamp body128may comprise a stationary portion that remains stationary while the clamp arm130amoves about the first pivot138a. The stationary portion comprises a distal-facing surface and the body grip162. The body grip162may comprise projections extending distally from the distal-facing surface. The distal-facing surface may be curved to conform to the shape of a humerus. In other configurations, the distal-facing surface may be shaped to conform to the shape of another bone or tissue. The projections and the stationary portion of the clamp body128may be monolithic in construction.

In some configurations, a user may first bring the body grip162into contact with the tissue to be gripped before operating the linear displacement mechanism140to move the clamp arms130a,130btoward each other and grip tissue. Specifically, a user may position the body grip against a relatively narrow portion of the humerus below a proximal head portion of the humerus. In other configurations, the user operates the linear displacement mechanism140to move the clamp arms130a,130btoward each other to grip tissue without first making contact with the body grip162. Contact of the clamp arms130a,130bwith the tissue may then bring the body grip162into contact with tissue.

The arm grip160amay be disposed at a fourth distance from the first pivot138a. The fourth distance may be greater than the third distance. When the fourth distance is greater than the third distance, the distal portion132aof the clamp arm130ais configured to pivot about the first pivot138aat a greater arc length than a given arc length of the second pivot144aabout the first pivot138a. In other words, the mechanical advantage between the second pivot144aand the first pivot138ato the first pivot138aand the arm grip160ais less than one. This allows a smaller input by the linear displacement mechanism144to result in a larger output (e.g., distance of travel or “throw”) of the distal portion132aof the clamp arm130a.

The clamp body128may define a channel164to receive the carrier142and permit the carrier142to move along the carrier axis CX. The carrier axis CX may be centered in the channel CX. The clamp body128may define one or more notches166a,166bthat further define the channel164. The notch166amay be configured to at least partially receive one of the clamp arms130ato permit the clamp arm130ato pivot about the first pivot138awith a greater range.

As shown inFIGS.3and4, the clamp body128may comprise a body attachment interface168for detachable coupling to the second extension attachment interface115of the extension arm108. The body attachment interface168may be oriented transverse to the carrier axis CX. The second extension arm interface115may comprise an extension arm rotational adjuster170. In a similar manner as the tracker rotational adjusters above118,120, the extension arm rotational adjuster170and the body attachment interface168may each comprise lock teeth opposing each other. The lock teeth on the extension arm rotational adjuster170and the lock teeth on the body attachment interface168may be configured to rotate relative to each other when spaced apart and rotatably lock when in engagement with each other. In the illustrated configuration, the body attachment interface168may be configured for kinematic coupling.

The body attachment interface168may define recesses172that are engaged by complementary projections174of the second extension arm interface115. The recesses may be “V-shaped.” The projections174of the second extension arm interface115and the recesses172of the body attachment interface168may be configured to rotate relative to each other when spaced apart and rotatably lock when in engagement with each other. The projections174may each comprise at least a partially spherical shape. The “V-shape” of the recesses172and the partially spherical shape of the projections174may provide the kinematic coupling by constraining the six degrees of freedom of movement between the clamp assembly126and the second extension attachment interface115. Specifically, body attachment interface168may define six recesses172. The second extension arm interface115may include three projections174to interface with three of the six recesses172. The spacing and number of the projections174and recesses172permits coupling between the between the clamp assembly126and the second extension attachment interface115to be coupled in six relative orientations. In other configurations, the number and spacing of projections174and recesses172may be different to permit more than six orientations or less than six orientations. It is contemplated that kinematic coupling may comprise the opposite configuration. It is also contemplated that kinematic coupling to constrain six degrees of freedom of movement may be achieved in other manners or by using other types of kinematic elements. In another configuration, connection between the extension arm rotational adjuster170and the body attachment interface168may be configured in any other suitable configuration for kinematic coupling or coupling otherwise the second extension attachment interface115to the clamp assembly126(e.g., threaded engagement).

The kinematic coupling between the clamp assembly126and the second extension attachment interface115is particularly useful during surgical applications by offering a repeatable mounting feature. For example, there may be instances during a surgical procedure where separation of the extension attachment interface115from the clamp assembly126may be necessary to allow movement of the clamped humerus relative to other anatomy without losing the relative position between the clamp assembly128and the humerus. In such a situation, the low profile of the clamp assembly126without the extension arm108or the tracker54may be more suitable to not impinge joint movement for surgery and tenting/tension of tissue and surrounding anatomy/surgical environment. The kinematic coupling between the clamp assembly126and the second extension attachment interface115enables the clamp assembly126and the second extension attachment interface115to be coupled and decoupled to each other without require re-registration of the tracker54to the clamp assembly126and/or the humerus.

The clamp assembly126described herein has several advantages. The clamp assembly126has a large throw size (range of motion) and is sized to fit between the fifth and ninety-fifth percentiles of humerus sizes which provides a wide applicability to surgical procedures without requiring different clamps for different sized patients. The clamp assembly126further provides a high clamping force as compared with conventional clamps. The clamp assembly126also exhibits a small footprint (i.e., is low profile) in the working area of a surgical site by operating two clamp arms130a,130bsimultaneously with a single input, which is particularly advantageous for a shoulder replacement surgery where there is limited incision size and surgeon access to the surgical site. This enables the surgical attachment system106, including the clamp assembly126, to be utilized in tight spaces and at difficult surgical access angles while providing the ability of the navigation tracker54to maintain line-of-sight to the localizer44. The small footprint of the surgical attachment system106further enables unobstructed post joint-reduction range of motion assessment. The clamp assembly126also provides the linear displacement mechanism140in an ergonomic and user-friendly position thereby reducing the risk of collisions at the surgical site. The clamp assembly126may also be affixed to any other type of anatomy or bone. Additionally, the clamp assembly126may be affixed on left or right sides of the patient anatomy. Other advantages can be understood from the detailed description and drawings. Other attachment mechanisms have included clamps that secure to the bone.

The above clamping and attachment system can be designed with a configuration, look, or function that differs specifically from the implementation shown in the Figures. The configurations are limited exclusively to the Figures and may include equivalents to any components described herein which operate with a similar function and accomplish a similar result.

It will be further appreciated that the terms “include,” “includes,” and “including” have the same meaning as the terms “comprise,” “comprises,” and “comprising.” Moreover, it will be appreciated that terms such as “first,” “second,” “third,” and the like are used herein to differentiate certain structural features and components for the non-limiting, illustrative purposes of clarity and consistency. Several configurations have been discussed in the foregoing description. However, the configurations discussed herein are not intended to be exhaustive or limit the invention to any particular form. The terminology which has been used is intended to be in the nature of words of description rather than of limitation. Many modifications and variations are possible in light of the above teachings may be practiced otherwise than as specifically described.