HK40018481B - Guide attachment for power tools - Google Patents

Description

Guide attachment for a power tool

Technical Field

The present disclosure relates to distal targeting devices for use with surgical implants, and more particularly, to distal targeting devices having adjustable attachment means for attaching the distal targeting device to power tools of various sizes and/or shapes.

Background

The surgical implant may include mechanisms that require external manipulation during or after implantation. For example, the implant may include anchoring elements, locking elements, position adjustment elements, or other types of elements or features that allow the implant to operate in a manner that promotes healing and/or stabilization of the patient's anatomy. One example of such an implant includes an intramedullary nail implanted within the intramedullary cavity of a long bone (such as a femur), for example, to stabilize a fracture in the bone. It is common practice to fix an intramedullary nail relative to bone by placing a locking member, such as a screw, through an access hole drilled through at least the cortical bone and aligned with an anchoring hole, such as a threaded hole, pre-drilled laterally in the nail. This procedure presents technical difficulties because the pre-drilled hole in the intramedullary nail is generally not visible to the surgeon and is difficult to locate and align with the surgical drill and placement instrument for drilling access holes in the bone and/or inserting locking members.

In many cases, a distal targeting system is used to detect the position of various elements of the implant during surgery. For the previous intramedullary nail example, a distal targeting system may be used with the surgical drill to locate the position of one or more anchor holes in the intramedullary nail and provide feedback to the physician to indicate the relative position of the anchor holes with respect to the distal end of the drill bit of the surgical drill. Such distal targeting systems may include a magnetic field generator (also referred to simply as a "field generator") having a central guide bore in which the drill bit is received. The field generator includes circuitry for generating one or more magnetic fields. The intramedullary nail may include one or more sensors, each sensor having one or more field transponders configured to detect the direction and strength of the magnetic field generated by the field generator. The one or more sensors may each transmit magnetic field data to a control unit having control circuitry. The one or more sensors may be positioned relative to the intramedullary nail such that the relative positions of the one or more sensors and the one or more anchoring holes are known by the control unit. The orientation and position of the central axis of the guide bore may also be known by the control unit. The central axis of the guide bore approximates the central axis of a drill bit received within the guide bore.

The control unit interprets the data from the one or more sensors to determine the orientation and displacement of the central axis of the guide bore relative to one or more anchoring bores in the intramedullary nail. The control unit transmits feedback to the physician, such as visual feedback through a viewing screen or audio feedback through a speaker, to indicate the orientation and/or displacement of the central axis relative to the anchoring hole in the intramedullary nail. Similar structures and techniques can be employed with distal targeting systems used with other types of surgical implants.

Disclosure of Invention

In one embodiment of the present disclosure, a distal targeting device for a surgical instrument includes: a field generator having a coupling element configured to receive a shaft elongated along an axis; and a bridge connectable to the field generator to be spaced from the field generator in a proximal direction relative to the axis. The bridge comprises an attachment device connectable to a tool configured to manipulate the shaft. The bridge also includes a pair of arms configured to clasp the body of the tool in a manner that generally rigidly couples the bridge to the tool. At least one of the arms is positionable at an adjustable distance relative to the attachment member to enable the arm to substantially rigidly clasp tool bodies having one or more of a variety of shapes and sizes.

In another embodiment of the present disclosure, a field generator configured to align a shaft of a surgical instrument with a target includes: a housing containing a field generator circuit; and a coupling element at least partially defining an opening having an open proximal end and an open distal end spaced apart from one another in a longitudinal direction. The opening is open in a transverse direction substantially perpendicular to the longitudinal direction to receive the shaft without the distal or proximal end of the shaft passing through the opening.

In another embodiment of the present disclosure, a distal targeting system includes a power tool having a tool body and a receiving element. The system includes a shaft that is elongated along an axis extending in a longitudinal direction. The proximal portion of the shaft is receivable in a receiving element of the power tool. The system includes a field generator having a coupling element configured to receive a shaft. The system also includes a bridge connectable to the field generator to be spaced from the field generator in a proximal direction relative to the axis. The bridge includes an attachment device connectable to the driving tool and a pair of arms configured to clasp the tool body in a manner that substantially rigidly couples the bridge to the tool. At least one of the arms is positionable at an adjustable distance relative to the attachment means such that the arm is capable of 1) substantially rigidly fastening the tool body, 2) releasing the tool body, and 3) substantially rigidly fastening a second tool body having one or more of a different size and shape than the tool body.

Drawings

The foregoing summary, as well as the following detailed description of exemplary embodiments of the distal targeting device of the present application, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the expandable intervertebral implant of the present application, there is shown in the drawings exemplary embodiments. However, it should be understood that this application is not limited to the precise arrangements and instrumentalities shown. In the drawings:

FIG. 1 is a perspective view of a distal targeting device coupled to a power tool to include a distal targeting system according to an embodiment of the present disclosure;

FIG. 2 is a top view of the distal targeting device of FIG. 1;

FIG. 3 is a top view of the distal targeting device of FIG. 1 with the clamping arms of the device in an extended position;

FIG. 4 is a perspective view of elements of an attachment device of the distal targeting device of FIG. 1;

FIG. 5 is an exploded view of a bridge of the distal targeting device of FIG. 1;

FIG. 6 is a cross-sectional side view of a proximal portion of a bridge of the distal targeting device of FIG. 1;

FIG. 7 is a partially exploded view of the bridge of FIG. 5, wherein a first step of assembling the attachment device is shown according to one example assembly sequence;

FIG. 8 is a partially exploded view of the bridge of FIG. 5, wherein a second step of assembling the attachment device is shown according to the example assembly sequence;

FIG. 9 is a partially exploded view of the bridge of FIG. 5, wherein a third step of assembling the attachment device is shown according to the example assembly sequence;

FIG. 10 is a partially exploded view of the bridge of FIG. 5, wherein a fourth step of assembling the attachment device is shown according to the example assembly sequence;

FIG. 11 is a perspective view of the bridge of FIG. 5, wherein a fifth step of assembling the attachment device is shown according to the example assembly sequence;

FIG. 12 is an exploded view of a field generator of the distal targeting device of FIG. 1;

FIG. 13 is a rear partially transparent perspective view of the assembled field generator of FIG. 12;

FIG. 14 is a partial cross-sectional end view of the coupling element of the field generator of FIG. 12, showing a slot for receiving a shaft of a power tool;

FIG. 15 is a rear view of the field generator of FIG. 12 with the rear housing cover of the field generator removed and the shaft mount shown in an open position;

FIG. 16 is a rear view similar to FIG. 15, showing the shaft mount in a closed position;

FIG. 17 is a partial cross-sectional end view of the coupling element of FIG. 14, showing the shaft fully seated in the slot and the shaft mount in a closed position;

FIG. 18 is a perspective cross-sectional side view of a coupling element of the field generator of FIG. 12;

FIG. 19 is another perspective cross-sectional side view of the coupling element with the shaft fully seated in the slot;

FIG. 20 is a side cross-sectional view of a retaining element for retaining the position of a shaft within a coupling element of a field generator according to another embodiment of the present disclosure;

FIG. 21 is a partial front perspective view of a coupling element of a field generator according to another embodiment of the present disclosure;

FIG. 22 is a front view of the coupling element of FIG. 21;

FIG. 23 is a top partially transparent view of the field generator of FIG. 12, showing the links of the field generator in a biased position prior to coupling with the bridge of FIG. 11;

FIG. 24 is a top partially transparent view of the field generator and bridge of FIG. 23, showing the coupling of the bridge engaged with the linkage in a manner that moves the linkage of the field generator away from the biased position;

FIG. 25 is a top partially transparent view of the field generator and bridge of FIG. 23, showing the links of the field generator in a latched position relative to the coupler of the bridge;

FIG. 26 is a top partially transparent view of the field generator and bridge of FIG. 23, showing the links of the field generator in a fully open position to decouple the bridge from the field generator;

FIG. 27 is a perspective view of a distal targeting device coupled to a power tool according to another embodiment of the present disclosure;

FIG. 28 is a cross-sectional end view of the distal targeting device of FIG. 27, showing the clamping arms of the device in a closed position;

FIG. 29 is a cross-sectional end view of the distal targeting device of FIG. 27, showing the clamping arms in another position and in phantom, in an optional fully open position;

FIG. 30 is a perspective view of a distal targeting device coupled to a power tool according to another embodiment of the present disclosure;

FIG. 31 is a partial cross-sectional end view of the distal targeting device of FIG. 30, showing the clamping arms in a closed position and in an open position in phantom;

FIG. 32 is a top view of the distal targeting device of FIG. 30;

FIG. 33 is a perspective cross-sectional view of the coupling element of the distal targeting device, taken along section line 33-33 of FIG. 30, wherein the coupling element is configured to carry a field generator;

FIG. 34 is another cross-sectional view of the coupling element of FIG. 33;

FIG. 35 illustrates a cross-sectional view of the coupling element of FIG. 34, wherein the coupling element is coupled to a branch of a bridge of the distal targeting device of FIG. 30;

FIG. 36 is a perspective view of a distal targeting device that employs a tether to couple the device to a power tool, wherein the tether is shown loosely attached, according to another embodiment of the present disclosure;

FIG. 37 is a perspective view of the distal targeting device of FIG. 36, showing the tether tightened;

FIG. 38 is a top view of the distal targeting device of FIG. 36 with the tether and tether tensioning mechanism removed for exemplary purposes;

FIG. 39 is a partial side view of the attachment device of the distal targeting device of FIG. 36;

FIG. 40 is a rear perspective view of a display assembly for use with the distal targeting device of the preceding figures, according to an embodiment of the present disclosure;

FIG. 41 is a perspective view of a display screen of the display assembly of FIG. 40; and is also provided with

Fig. 42 is a perspective view of the display assembly of fig. 40 coupled to the distal system device of fig. 1.

Detailed Description

In procedures involving distal targeting of an implant with a surgical instrument, it is advantageous to provide as precise a relationship as possible between the implant and the surgical instrument. The present disclosure relates to a distal targeting device that may be mounted on a surgical instrument, such as a power drill, to guide a physician in an attempt to align a distal portion of the surgical instrument, such as a distal end of a drill bit, with a portion of a surgical implant disposed within a patient. In particular, the distal targeting devices disclosed herein all have adjustable mounting elements that allow for easy mounting of the targeting device to surgical instruments of various sizes and/or shapes in a sturdy and rigid manner. This allows the distal targeting device and any of a number of surgical instruments to be used as a distal targeting system by a physician. As a non-limiting example, most power drills designed to drill access holes in cortical bone are commercially produced, and thus the width of the corresponding tool, such as at the motor fairing, is in the range of about 2.50cm to about 5.12 cm. The size of the mounting elements of the distal targeting devices disclosed herein are adjustable to couple to a power having a width within the aforementioned range. Thus, the mounting elements disclosed herein for a distal targeting device can be characterized as "universal mounting elements". The distal targeting devices disclosed herein provide significant commercial advantages because the same targeting device can be used for most commercially available power drills within the surgical field, such as the field of intramedullary nail implantation.

The present disclosure also relates to a field generator of a distal targeting device. In particular, the field generators disclosed herein include a lateral access opening that allows a portion of the drill bit to be inserted laterally into the field generator, rather than requiring that substantially the entire drill bit be inserted axially through the opening, starting from the distal end or starting from the proximal end. In addition, the field generator disclosed herein is connectable to the mounting element of the distal targeting device in the following manner: such that the field generator is supported by the mounting element when the drill bit extends through the opening of the field generator. In this way, the field generator does not exert substantial bending moments on the drill bit during operation. Thus, no assistant is required to manually stabilize the field generator while the physician is operating the power drill.

Referring now to fig. 1, an embodiment of a distal targeting system is shown that includes a distal targeting device 2 mounted to a tool 4 configured to receive and manipulate a shaft 6 for insertion into a patient. As shown, the tool 4 may be a power tool for rotating the shaft 6, such as a hand power drill. The shaft 6 may be a pointed tip, such as a drill bit, a drive head, or any other type of shaft for targeted insertion into a patient. The power tool 4 may include a receiving element, such as a chuck 8, for receiving the proximal portion 10 of the shaft 6. The shaft 6 defines a distal end 12 spaced apart from the proximal portion 10 in a distal direction. The distal targeting device 2 may comprise a field generator 14 for generating a magnetic field as described above. The field generator 14 comprises a coupling element 16 configured to receive a portion of the shaft 6. The shaft 6 defines a shaft axis 18 extending in the longitudinal direction X.

The distal targeting device 2 comprises a mounting element 20 extending from the field generator 14 in a proximal direction opposite to the distal direction. It should be appreciated that the proximal and distal directions are unidirectional components of the bi-directional longitudinal direction X, respectively. The mounting element 20 is configured to mount the field generator 14 to a body 21 of the power tool 4. Thus, the mounting element 20 is also referred to herein as a "bridge". In the illustrated embodiment, the bridge 20 is mounted to a top portion 22 of the tool body 21, such as a motor fairing. However, in other embodiments, the bridge 20 may be mounted to other portions of the tool body 21, such as the base 24 of the handle 26. The bridge 20 is adjustable so that the field generator 14 can be mounted to power tools 4 of various sizes and/or various shapes.

The bridge 20 may also define a pair of distally extending branches 28 that extend outwardly relative to a lateral direction Y that is substantially perpendicular to the longitudinal direction X. Both the longitudinal direction X and the lateral direction Y may be referred to as "horizontal" directions. In addition, any plane that is coextensive with both the longitudinal direction X and the lateral direction Y may be referred to as a horizontal plane. Both the longitudinal direction X and the lateral direction Y are perpendicular to the vertical direction Z. As used herein, the term "longitudinal" refers to "along a longitudinal direction X"; the term "lateral" means "along a lateral direction Y"; and the term "vertical" means "in the vertical direction Z". As used herein, "vertical-longitudinal plane" refers to a plane extending in a vertical direction Z and a longitudinal direction X; and "vertical-lateral plane" refers to a plane extending in the vertical direction Z and the lateral direction Y.

The distal end 30 of the branch 28 may be coupled to the field generator 14, as discussed in more detail below. The branches 28 may define lateral spaces 32 therebetween such that the shaft 6 may extend distally from the power tool 4 through the lateral spaces 32 and into the coupling element 16 of the field generator 14. The bridge 20 may include an attachment device 34 that is connectable to the tool body 21 and a pair of clamping arms 36. The attachment means 34 may be configured to operate the arm 36 to clasp the tool body 21 in a manner that substantially rigidly couples the bridge 20 to the tool 4. In this way, the attachment device 34 and the clamping arm 36 may cooperatively define a clamp.

As shown in fig. 2 and 3, the arms 36 may be configured to contact opposite sides of the tool body 21 to clamp or otherwise clasp the tool body 21 between the arms 36. One or both of the arms 36 may be positionally adjustable relative to the attachment device 34 to clamp to power tools 4 of various sizes and/or shapes. For example, each arm 36 may define a respective arm distance D1, D2 measured in the lateral direction Y from a central vertical-longitudinal plane P (i.e., a plane coextensive with the shaft axis 18 and extending in the vertical direction Z) to the inner contact surface 38 of the arm 36. The vertical direction Z is substantially perpendicular to the longitudinal direction X and the lateral direction Y. The inner contact surface 38 of the arm 36 may define a curved concave profile in a vertical-lateral plane. The foregoing profile may enhance the gripping grip of the arms 36 on the tool body 21, particularly when the tool body 21 has a rounded convex profile in the vertical-lateral plane. The inner surface 38 of the arm 36 may also include a layer of high friction material to increase the gripping grip of the arm 36 on the tool body 21.

With continued reference to fig. 2 and 3, both arms 36 may be manipulated by the attachment device 34 to adjust the respective arm distances D1, D2 as needed to clamp to the power tool 4. In the embodiment shown, the arm distances D1, D2 can be adjusted between a minimum value of about 1.00cm (fig. 2) and a maximum value of about 3.50cm (fig. 3), respectively. As described above, this arm distance D1, D2 range is sufficient to allow the bridge 20 to be mounted to most power tools 4 for use with intramedullary nails, including power tools 4 having various shapes and/or sizes. In other embodiments, one of the arms 36 may be static while the other is adjustable to clamp to the power tool 4. The arm 36 and the attachment device 34 may collectively define a rack and pinion mechanism to adjust the arm distances D1, D2. In particular, the arms 36 may each define an adjustment portion 40 that is elongated in the lateral direction Y and configured to engage an actuator 42 of the attachment device 34. The adjustment portion 40 of each arm 36 may define a rack 44 having linearly aligned rack teeth 46. The actuator 42 may include an actuation shaft 48 (shown in fig. 5) carrying a pinion gear 50 having radial pinion teeth 52 configured to intermesh with the rack teeth 46. The actuator 42 may include a knob 54 coupled to the pinion gear 50. Knob 54 may allow manual rotation of pinion 50 about a central axis 56 (fig. 5) of actuation shaft 48 to translate clamping arm 36 to adjust arm distances D1, D2.

Referring now to fig. 4, the attachment device 34 may include an arm expansion inhibitor, such as a ratchet configured to prevent the arm 36 from moving laterally outward after clamping the arm 36 to the tool body 21. The ratchet may include ratchet teeth 58 circumferentially spaced about the actuation shaft 48. Ratchet teeth 58 may be positioned vertically between pinion 50 and knob 54. The ratchet may include a pawl 60 configured to engage the ratchet teeth 58 and a pawl spring 62 coupled to the pawl 60. The pawl 60 may be configured to engage the ratchet teeth 58 to allow the pinion gear 50 to rotate in a first rotational direction R1 to reduce the arm distances D1, D2 while preventing the pinion gear 50 from rotating about a second rotational direction R2 opposite the first rotational direction R1. Although only one pawl 60 is present in the illustrated embodiment, it should be understood that additional pawls 60 may be employed to engage the ratchet teeth 58. The actuator 42 may include a rod 64 extending below the pinion gear 50. The actuator 42 may also include a flange 66 at the bottom end of the rod 64.

Referring now to fig. 5 and 6, the body 68 of the bridge 20 may define a frame 70 configured to support components of the attachment device 34. The underside 71 of the frame 70 may be contoured to mate with the top surface of the power tool 4. The underside 71 of the frame 70 may also be curved and concave in the vertical-lateral plane to enhance the fit of the frame 70 with the tool body 21, as most tool bodies 21 of power tools 4 have at least partially convex and circular profiles in the vertical-lateral plane. The frame 70 may be configured to receive the clamp arm 36, the actuator 42, the pawl 60, and the pawl spring 62. The frame 70 may include a pawl receiving recess 72 for receiving the pawl 60 and a spring mount 74 within the recess for mounting the pawl spring 62 to the frame 70. The frame 70 may also be configured to attachably receive a detent cover 76 and a frame cover 78, respectively, defining the outer surface of the bridge 20. The frame 70 may include a main support surface 80 configured to contact the underside of the adjustment portion 40 of each clamp arm 36. In this regard, the main support surface 80 may define a bearing surface for the clamp arm 36. As shown, the main support surface 80 may be substantially planar, although other configurations are within the scope of the present disclosure. The frame 70 may define a rail for each arm 36. Each rail may extend laterally and may guide the arm 36 to move in the lateral direction Y. In the illustrated embodiment, the guide tracks each include a guide channel 82 recessed into the bridge body 68 from the main support surface 80. The guide channels 82 may each be configured to receive a corresponding guide projection 84 on the underside of the adjustment portion 40 of the arm 36. The guide channel 82 and the guide projection 84 may have corresponding dovetail profiles in a vertical-longitudinal plane that are configured to prevent movement of the arm 36 in the vertical direction Z and/or the longitudinal direction X relative to the frame 70 during adjustment of the arm distances D1, D2. The frame 70 may also define a pair of abutment shoulders 86 at lateral sides of the bridge body 68. The abutment shoulder 86 may be configured to contact an abutment tab 88 extending outwardly from the adjustment portion 40 of the arm 36 opposite the rack teeth 46. In this way, lateral translation of the clamp arm 36 may be limited as desired. It should be appreciated that the bridge 20 may be provided in a kit that includes interchangeable gripping arms 36 of various sizes and/or various inner surface 38 configurations to further adapt the bridge 20 to power tools of various sizes and/or shapes.

The frame 70 may define a vertical aperture 90 for receiving the rod 64 of the actuator 42. The vertical bore 90 may have an upper bore portion 92 and a lower bore portion 94 having a larger diameter than the upper bore portion 92 to define a shoulder 96 therebetween. As shown in fig. 6, the upper and lower bore portions 92, 94 may be configured such that the bottom flange 66 of the actuator 42 may translate vertically within the lower bore portion 94, but is prevented from translating upward into the upper bore portion 92 due to interference of the shoulder 96. In fig. 6, the actuator 42 is shown in a first vertical position relative to the frame 70 with the flange 66 at the bottom of the vertical bore 90, the pinion gear 50 engaged with the rack teeth 46, and the pawl 60 engaged with the ratchet teeth 58. It should be appreciated that to disengage the actuator 42, the practitioner may move the actuator 42 to the second vertical position relative to the frame 70 by pulling the knob 54 upward until the flange 66 abuts the shoulder 96, thereby placing the actuator 42 in the second vertical position. In the second vertical position, the pinion gear 50 may be vertically spaced from the rack teeth 46 and the ratchet teeth 58 may be vertically spaced from the pawl 60. From the second position, the practitioner can depress the knob 54 in order to move the pinion gear 50 and the ratchet teeth 58 into engagement with the rack teeth 46 and the pawl 60, respectively.

It should be appreciated that the frame 70 and the actuator 42 may collectively include a position locking feature that may be actuated to hold the actuator 42 in either the first vertical position or the second vertical position. For example, the position locking feature may be configured such that a practitioner may pull the knob 54 upward to move the actuator 42 to the second vertical position, and may then lock the actuator 42 therein by rotating the knob 54 a quarter turn in one of the first or second rotational directions R1, R2. To unlock the actuator 42 from the second vertical position, the practitioner may rotate the knob 54 a quarter turn in the other rotational direction R2, R1, and then may press the knob 54 such that the actuator 42 moves to the first vertical position. Other position locking functions are within the scope of the present disclosure. In further embodiments, the attachment device 34 may include a biasing element, such as a spring element, that may be disposed within the lower bore portion 94 and may abut the shoulder 96 and the bottom flange 66, for example, in a manner that biases the actuator 42 in the first vertical position.

As shown in fig. 5, the frame 70 may also define a side recess 98 in one lateral side of the frame 70 and a lateral slot 100 extending inwardly from the side recess 98 and opening into the vertical bore 90. The lateral slot 100 may include an upper slot portion 102 laterally coextensive with the upper aperture portion 92 and a lower slot portion 104 laterally coextensive with the lower aperture portion 94. The lower slot portion 104 may be wider than the upper slot portion 102 and may be configured to receive the flange 66. In this manner, actuator 42 may be laterally inserted into vertical bore 90 through lateral slot 100 with flange 66 passing through lower slot portion 104 and rod 64 passing through upper slot portion 102.

The attachment device 34 may include an insert, such as a locking clip 106, configured to hold the actuator 42 with the vertical bore 90. The locking clip 106 may define a tab 107 configured to extend within the lateral slot 100. Once fully inserted into the lateral slot 100, the tab may also define a portion of each of the upper and lower hole portions 92, 94. The locking clip 106 may also define a portion of one or more guide channels 82. The locking clip 106 may also define a first mounting formation 108, and opposite lateral sides of the frame 70 may define a second mounting formation 109. The first and second mounting formations 108, 109 may be configured to receive corresponding mounting features on the underside of the frame cover 78 to secure the frame cover 78 to the frame 70.

Referring to fig. 7-11, assembly of the attachment device 34 of the bridge 20 will now be described according to an example assembly sequence. As shown in fig. 7, the clamp arm 36 may be laterally inserted into the frame 70 such that the underside of the adjustment portion 40 of the arm 36 contacts the main support surface 80 and the guide projection 84 of the arm 36 extends in the guide channel 82 of the frame 70. Referring now to fig. 8, the actuator 42 may be inserted into the vertical bore 90. As described above, the actuator 42 may be inserted laterally into the vertical bore 90 through the lateral slot 100. During lateral insertion of the actuator 42, the actuator 42 may be in the second vertical position, whereby the pinion gear 50 and the ratchet teeth 58 are prevented from interference by the rack teeth 46 and the pawl 60, respectively. Referring now to fig. 9, pawl 60 and pawl spring 62 may be mounted within pawl receiving recess 72. Referring to fig. 10, a pawl cover 76 may be attached to the frame 70. The locking clip 106 may also be inserted laterally into the side recess 98 such that the protrusion 107 extends within the lateral slot 100 and completes the upper and lower hole portions 92, 94 of the vertical hole 90. In this manner, the locking clip 100 may lock the actuator 42 to the bridge body 68. Referring now to fig. 11, a frame cover 78 may be attached to the frame 70. It should be understood that other sequences of assembling the attachment device 34 are within the scope of the present disclosure.

With continued reference to fig. 11, the bridge 20 may include one or more wire holders 110 for holding wires, cords or cables of the distal targeting device 2. The distal end 30 of the branch 28 may include one or more couplers 112 for coupling with the field generator 14. As shown, the couplers 112 may each include a coupler base 114 extending distally from the associated branch 28. The couplers 112 may also each define a prong 116 extending laterally from the coupler base 114. Each prong 116 may define a proximal surface 118 extending orthogonally from the coupler base 114 and a tapered surface 120 extending from the proximal surface 118 to a distal surface 122 of the coupler base 114. Coupler 112 may be configured to engage a link of field generator 14, as described below.

Referring now to fig. 12, the field generator 14 may include a front housing 130 containing field generator circuitry. The front housing 130 may include at least a portion of the coupling element 16 configured to receive a portion of the shaft 6. The coupling element 16 may at least partially define an opening 132 having an open proximal end 134 and an open distal end 136 spaced from the open proximal end 134 in a distal direction. The opening 132 is open to the outside of the field generator 14 in the transverse direction T. The transverse direction T may be any direction substantially orthogonal to the longitudinal direction X. As used herein, the term "transverse" refers to along a transverse direction T. The opening 132 allows the shaft 6 to be inserted laterally into the coupling element 16 of the field generator 14. In this way, the shaft 6 may be inserted into the field generator 14 without the distal end 12 or the proximal end 10 of the shaft 6 passing through the opening 16. This greatly simplifies the process of inserting the shaft 6 into the field generator 14, which in prior art distal targeting devices may require that nearly the entire length of the shaft be inserted axially through the opening, starting from the distal end or starting from the proximal end. The opening 132 may be located in a top portion 138 of the front housing 130 opposite the central region of the field generator 14. However, in other embodiments, the opening 132 may extend to a central region of the field generator 14. The top portion 138 of the front housing 130 may also define a pair of receivers 140 for receiving the couplers 112 at the distal ends 30 of the branches 28 of the bridge 20, as set forth in more detail below.

The field generator 14 may include a rear housing cover 142 configured to be coupled to a rear side 144 of the front housing 130 to define a rear housing compartment 146 therebetween. The field generator 14 may include a linkage 148 and a retainer 150 within the rear housing compartment 146. The link 148 may be configured to latch with the coupler 112 of the bridge 20. The retainer 150 may be configured to engage the shaft 6 to retain the shaft 6 within the opening 132. The field generator may include biasing elements, such as coil springs 152, configured to bias the links 148 and the retainers 150, respectively, to respective biased positions. The rear housing cover 142 may be configured to releasably attach with the front housing 130. In this manner, as a non-limiting example, the field generator 14 may be disassembled or at least partially disassembled as desired, such as for cleaning, maintenance, and/or refurbishment.

The link 148 may have a generally plate-shaped body 154 having a front surface 156 and a rear surface 158 spaced apart from one another along the longitudinal direction X. The link body 154 may define a protrusion extending proximally from the rear surface 158, such as a side rail 160. The link 148 may also include a follower extending proximally from the rear surface 158, such as a first tab 162. The tab 162 may be configured to allow the practitioner to move the link 148 laterally away from the link biasing position to the link depressing position. The link body 154 may define a recess 164 in the rear surface 158 and a bore 166 extending distally from the recess 164 through the link body 154. The link 148 may include a pair of latches 168 extending from a top surface 170 of the link body 154. Each latch 168 may define a tapered proximal surface 172 and a distal surface 174. The latch 168 may be configured to latch with the coupler 112 of the bridge 20, as described more fully below.

The retainer 150 may have a generally plate-shaped body 176 having a front surface 178 and a rear surface 180 spaced apart from one another along the longitudinal direction X. The retainer 150 may be configured to be at least partially seated within a recess 164 in the rear surface 158 of the link 148. The retainer body 176 may define a protrusion, such as a lateral rail 182, extending proximally from the rear surface 180. The retainer 150 may also include a compression member, such as a second push tab 184, extending proximally from the rear surface 180. The second push tab 184 may be configured to allow a practitioner to move the retainer 150 laterally away from the retainer bias position to the retainer depressed position. The retainer 150 may include a shaft mount 186 extending from a top surface 188 of the retainer body 176. The shaft mount 186 may extend distally to overlie the top surface 170 of the link body 154. The shaft mount 186 may define a bearing surface 190 configured to stabilize the bearing portion of the shaft 6 when the shaft 6 is fully inserted into the opening 132 and the retainer 150 is in the retainer biased position.

With continued reference to fig. 12, the rear housing cover 142 may define an aperture 192 through which the first tab 162 and the second tab 184 may extend. The front surface 194 of the rear housing cover 142 may define a guide slot 196 that is elongated in the lateral direction Y. The guide slot 196 is configured to receive the lateral rails 160, 182 of the link 148 and the retainer 150, respectively, to guide lateral movement of the link 148 and the retainer 150 between their respective biased and depressed positions. The rear housing cover 142 may also include a receptacle, such as electrical receptacle 198, for coupling the field generator circuit to one or more wires, cords or cables.

Referring now to fig. 13, a front perspective view of the field generator 14 is shown, wherein the front housing 130 is a transparent view to illustrate the link 148 and the retainer 150 coupled to the rear housing cover 142. The link 148 and the retainer 150, respectively, are shown in their respective biased positions in fig. 13. The first and second mounting posts 200, 202 may extend distally from the front surface 194 of the rear housing cover 142. The third mounting post 204 may extend distally from the front surface 156 of the link 148. A fourth mounting post 206 may extend distally from the front surface 194 of the retainer 150 and through the aperture 166 of the link 148. The first mounting post 200 and the third mounting post 204 may be substantially laterally aligned and may mount opposite ends of one coil spring 152. Similarly, the second mounting post 202 and the fourth mounting post 206 may be substantially laterally aligned and may mount opposite ends of the other coil spring 152. The coil spring 152 may be a tension spring configured to pull the link 148 and the retainer 150 toward their respective biased positions.

Referring now to fig. 14, the opening 132 may be a slot 208 defined by the coupling element 16 of the field generator 14. The slot 208 may define an insertion path for the shaft 6, also referred to as an insertion axis 209. The insertion axis 209 may have a linear and/or curved section. The insertion axis 209 may also extend substantially entirely in the transverse direction T. In other words, the insertion axis 209 may be such that any line extending between any two points on the insertion axis 209 will extend substantially transverse to the longitudinal direction X. The inner end 210 of the slot 208 may define a bearing surface 212 configured to stabilize a bearing portion of the shaft 6 during operation of the power tool 4. The bearing surface 212 may be characterized as a "shaft seat" or simply a "seat" of the field generator 14. Thus, when the shaft 6 is fully seated within the slot 208, the inner end of the insertion axis 209 may be coincident with the shaft axis 18. As shown, the mount may be offset from the geometric center of the field generator 14 at least with respect to the lateral direction T (such as the vertical direction Z). In this way, the seat may be located near the top of the field generator 14, allowing the shaft 6 to be easily inserted therein. However, in other embodiments, the mount may be located substantially at the geometric center of the field generator 14 (or at least at the geometric center of the field generator circuit). As shown in fig. 14, the slot 208 may include one or more straight portions 214 and one or more curved portions 216.

The bearing surface 212 may be defined by a bearing 218 located at the inner end 210 of the slot 208. In some embodiments, the bearing 218 may include a layer of low friction material. The bearing surface 212 may be finished to reduce its surface finish roughness to reduce friction between the bearing surface 212 and the shaft 6. In other embodiments, the bearing 218 may include an effective load bearing element, such as a plurality of roller bearings or ball bearings, dispersed along the load bearing surface 212. In other embodiments, the bearing surface 212 may be defined by the field generator housing itself, such as by the front housing 130. In further embodiments, the field generator 14 may employ a lubrication system to lubricate the bearing surfaces to reduce friction with the shaft 6 during operation. It should be understood that other load bearing features for the shaft and/or the coupling element 16 of the field generator 14 are within the scope of the present disclosure.

Referring now to fig. 15, in the illustrated embodiment, to insert shaft 6 into slot 208, the practitioner can use second tab 184 to push retainer 150 into the depressed retainer position, as shown. With the shaft 6 inserted into the slot 208 and the retainer 150 pressed into the depressed retainer position, the shaft 6 is free from the retainer 150. When the practitioner releases the second tab 184, the retainer 150 is biased to the retainer biased position, as shown in fig. 16 and 17. In the retainer biased position, the shaft mount 186 may be very close together and may optionally abut the shaft 6. In this retainer biased position, the retainer 150 retains the shaft in the fully seated position. As with the bearing surface 212 of the slot 208, the bearing surface 190 of the retainer 150 may employ one or more of the following: a layer of low friction material, surface finish, effective load bearing elements, lubrication, any combination of the foregoing, or any other type of load bearing feature for reducing friction with the shaft 6. The shaft 6 and the coupling element 16 may optionally be cooperatively configured such that when the shaft is fully seated, there is a small gap between the shaft 6 and one or more of the bearing surfaces 190, 212. In other embodiments, the shaft 6 and the coupling element 16 may be cooperatively configured such that, as shown by the dashed line 6a, the shaft 6 is bearing-wise abutted against one or more of the bearing surfaces 190, 212 while being rotatable about the shaft axis 18 in a substantially unrestricted manner. In the illustrated embodiment, with the retainer 150 in the biased retainer position, the bearing surfaces 190, 212 may substantially fix the lateral position of the shaft 6 relative to the field generator 14, which improves the distal targeting accuracy of the distal targeting system. It should be appreciated that the coupling member 16 may be configured to accommodate shafts within a range of diameters. It will also be appreciated that the coupling element may be scaled up or down as required to accommodate the diameter of the further shaft 6.

Referring now to fig. 18, the opening 132 of the coupling element 16 may include one or more axial retention elements configured to engage corresponding axial retention elements of the shaft. The opening 132 and the axial retention element of the shaft 6 may be cooperatively configured to prevent axial movement of the shaft 6 relative to the field generator 14 at least when the shaft 6 is fully seated within the slot 208. As shown, the axial retention element of the opening 132 may include one or more abutment surfaces of the coupling element 16. For example, the coupling element 16 may define a proximal abutment surface 220 and a distal abutment surface 222 spaced apart from the proximal abutment surface 220 in the distal direction. Proximal abutment surface 220 may be positioned at a proximal end of opening 132. The distal abutment surface 220 may be located distally of each of the link 148 and the retainer 150, but proximal of the distal end 136 of the opening 132. One or both of the proximal and distal abutment surfaces 200, 222 may be orthogonal to the longitudinal direction X.

Referring now to fig. 19, the shaft 6 may define a bearing portion 224 configured to extend within the opening 132 and couple with the coupling element 16 in a manner that prevents axial translation of the shaft 6 relative to the field generator 14. As shown, the shaft bearing portion 224 may include a proximal flange 226 and a distal flange 228. The inner surfaces of the flanges 226, 228 may be longitudinally spaced from each other a distance that is substantially equal to, but not less than, the longitudinal distance between the proximal abutment surface 220 and the distal abutment surface 222. In this way, the abutment surfaces 220, 220 and the flanges 226, 288 can cooperatively prevent axial translation of the shaft 6 relative to the field generator when the bearing portion 224 of the shaft 6 is fully seated within the slot 208. In this way, the axial position of the shaft 6 may be substantially fixed relative to the field generator 14, which further improves the distal targeting accuracy of the distal targeting system. A side edge 230 of the opening 132 may be connected to each of the proximal and distal abutment surfaces 220, 222 to form a guide effective to guide the flanges 226, 228 into abutment with the abutment surfaces 220, 222. The inner surface of one or more of the flanges 226, 228 and the outer surface 232 of the shaft 6 between the flanges 226, 228 may be finished to reduce the surface finish roughness thereof to reduce friction between the shaft 6 and the coupling element 16. In other embodiments, the bearing portion 224 of the shaft 6 may include one or more layers of an external low friction material to reduce friction between the shaft 6 and the coupling element 16. In other embodiments, as a non-limiting example, the bearing portion 224 of the shaft 6 may include one or more effective bearing elements, such as journal bearings, roller bearings, ball bearings, thrust bearings (for the flanges 226, 228) to reduce friction between the shaft 6 and the coupling element 16.

Referring now to fig. 20, another embodiment of an axial retention element is shown. In this embodiment, the shaft 6 may define a ball flange 234 and the coupling element 16 may define an at least partially spherical recess 236 in which the ball flange 234 is seated. As described above, the coupling member 16 defines the lateral access opening 132a. In other embodiments, the bearing portion 224 of the shaft 6 may define a single cylindrical flange configured to rest within a single cylindrical recess within the coupling element 16. It should be understood that other axial retention configurations of the shaft 6 are within the scope of the present disclosure.

Referring now to fig. 21 and 22, an example of a field generator 14 having a coupling element 16 with an opening 132b that is partially oblique relative to the longitudinal direction X is shown. The partially angled opening 132b may include an angled upper slot portion 208a and a longitudinal lower slot portion 208b (fig. 22). In this embodiment, the longitudinal lower slot portion 208b may define a bearing surface 212. In such an embodiment, at least a portion of the shaft 6 may enter the opening 132 at an oblique angle with respect to the longitudinal direction X. The inclined upper slot portion 208a may be configured to leak the shaft 6 into the longitudinal lower slot portion 208b when the shaft 6 moves downward in the opening 132b. The partially inclined opening 132b may be characterized as a lateral access opening because each point on the shaft 6 may be moved substantially in the lateral direction T when the shaft 6 is inserted into the opening 132. It should be understood that other types of lateral access opening configurations are within the scope of the present disclosure.

With reference to fig. 23-26, an example mode of releasably coupling the field generator 14 to the bridge 20 will now be described. As used herein, the term "releasably coupled" and derivatives thereof refer to the repeated coupling and uncoupling in a non-destructive manner. As shown in fig. 23, the bridge 20 may be advanced distally toward the field generator 14 (or the field generator 14 may be advanced proximally toward the bridge 20) such that the coupler 112 at the distal end 30 of the branch 28 aligns with the receiver 140 (fig. 12) in the top portion 138 of the front housing 130. As shown in fig. 24, the bridge 20 may be advanced further into the receiver 140 such that the coupler 112 engages an associated latch 168 of the link 148. As bridge 20 continues to advance distally within receiver 140, distal tapered surface 120 of coupler 112 engages proximal tapered surface 172 of latch 168, which causes latch 168 to translate laterally. As shown in fig. 25, once the tip 116 is advanced distally beyond the latch 168, the link 148 and its latch 168 are biased back to the link-biased position, whereby the distal surface 174 of the latch 168 latches behind the proximal surface 118 of the tip 116, thereby causing mechanical interference in the proximal direction. In this manner, once the tip 116 is advanced distally beyond the latch 168, the latch 168 and coupler 112 rigidly couple the bridge 20 to the field generator 14. To release the coupler 112 from the latch 168, the practitioner can depress the first tab 162 to move the link 148 to the link depressed position, as shown in fig. 26, thereby allowing the bridge 20 to be uncoupled proximally from the field generator 14.

Referring now to fig. 27, another embodiment of a distal targeting device 1002 is shown. The distal targeting device 1002 may be similar to the distal targeting device 2 described above. The distal targeting device 1002 may include a bridge 1020 having an attachment device 1034 that is connectable to the power tool 1004. The bridge 1020 has a pair of clamp arms 1036 configured to clasp the body 1021 of the tool 1004 in a manner that generally rigidly couples the bridge 1020 to the power tool 1004. The clamp arms 1036 can be positioned at an adjustable distance relative to the attachment device 1034 such that the arms 1036 can substantially rigidly clasp the tool body 1021 having one or more of a variety of shapes and/or sizes therebetween. The bridge 1020 may include a pair of branches 1028 extending laterally outward on either side of the shaft 1006 and coupled to the coupling element 1016. Although a field generator is not shown in fig. 27, the coupling element 1016 may be configured to carry a field generator.

In this embodiment, the clamp arms 1036 may be configured as spring-hinge clamps configured to bias the clamp arms 1036 against the tool body 1021. One or more of the clamp arms 1036 may be coupled to the attachment device 1034 at a spring hinge 1035 defining a hinge axis 1037 oriented substantially in the longitudinal direction X. As shown, the bridge 1020 may include two (2) pairs of spring hinge arms 1036, but in other embodiments the bridge 1020 may have a pair of opposing spring hinge arms 1036. As shown in fig. 28 and 29, at the spring hinge 1035, the clamp arms 1036 may each define a first spring mount 1039 that faces a second spring mount 1041 defined by the attachment device 1034. The second spring mount 1041 may be located in a hinge recess 1043 defined by the attachment device 1034. A biasing element such as a tension spring 1045 may be mounted to the first and second spring mounts 1039, 1041 in a manner that biases the clamp arm 1036 against the tool body 1021 toward the fully clamped position. In this way, as shown in fig. 29, the clamp arm 1036 can rigidly clasp tool bodies 1021 of various sizes and/or shapes. Thus, the tension spring 1045 may be characterized as an "actuator" for gripping the clamp arm 1036. The spring hinge 1035 may also define a toggle such that when the arm 1036 is rotated outwardly beyond the toggle, the arm 1036 is biased to the fully open position O, as shown in fig. 29. As described above, the inner surface 1038 of the arms 1036 may include a layer of high friction material to increase the gripping grip of the arms 1036 on the tool body 1021. The underside 1071 of the attachment device 1034 may be contoured (such as by being curved and concave in a vertical-lateral plane) to mate with a top surface of the power tool 1004.

Referring now to fig. 30, another embodiment of a distal targeting device 2002 is shown. The distal targeting device 2002 may be similar to the distal targeting device 2, 1002 described above. The distal targeting device 2002 may include a bridge 2020 having an attachment device 2034 connectable to the power tool 2004. Bridge 2020 has a pair of clamp arms 2036 configured to clasp the body 2021 of tool 2004 in a manner that generally rigidly couples bridge 2020 to power tool 2004. The clamping arms 2036 can be positioned at an adjustable distance relative to the attachment device 2034 such that the arms 2036 can generally rigidly clasp the tool body 2021 having one or more of a variety of shapes and/or sizes. Bridge 2020 may include a frame 2070 supporting an attachment device 2034. Bridge 2020 may include a pair of branches 2028 that extend laterally outward on either side of shaft 2006 and are coupled to coupling element 2016. Although the field generator is not shown in fig. 30, the coupling element 2016 may be configured to carry the field generator.

Referring now to fig. 31, clamp arms 2036 may be coupled to a frame 2070 at respective pivot joints, such as hinges 2035. The hinges 2035 may each define a hinge axis 2037 about which the clamp arm 2036 rotates. Hinge axis 2037 may be oriented substantially in longitudinal direction X. The clamp arm 2036 may define a first portion 2039 that extends from the hinge 2035 to the tool body 2021. The first portion 2039 of the arm 2036 may define an interior tool contact surface 2038 configured to contact the tool body 2021. As described above, the inner tool contact surface 2038 of the arm 2036 may include a layer of high friction material to increase the gripping grip of the arm 2036 on the tool body 2021. The clamp arm 2036 may also define a second portion 2041 of an actuator (such as translation member 2050) that extends from the hinge 2035 to the attachment device 2034. The second portion 2041 of the clamp arm 2036 may define an internal actuation contact surface 2043 configured to engage the translating member 2050. It should be appreciated that the attachment device 2034 may optionally include a cover (not shown), such as a top-fold cover, to cover at least a portion of the translating member 2050 and the clamp arm 2036.

Referring again to fig. 30, translating member 2050 may be configured to translate along translation axis 2056 in a manner that biases inner tool contact surface 2038 of clamp arm 2036 against tool body 2021. As shown, translation axis 2056 may be oriented in longitudinal direction X, although other orientations are possible. Translating member 2050 may include a knob 2055 that allows for easier manipulation of translating member 2050. Translating member 2050 may define one or more external contact surfaces 2051 configured to engage with the internal actuation contact surfaces 2043 of arms 2036. As shown, one or more outer contact surfaces 2051 of translating member 2050 may be inclined relative to longitudinal direction X in a manner that provides translating member 2050 with a wedge-shaped configuration. The outer contact surface 2051 may taper inwardly in a proximal direction, as shown. The inner actuation contact surface 2043 of one or more of the arms 2036 may also be inclined relative to the longitudinal direction X. At least a portion of the inner actuation contact surface 2043 may be conical to increase in width in the proximal direction. The outer contact surface 2051 of the translating member 2050 and the inner actuation contact surface 2043 of the arm 2036 may be cooperatively configured such that a practitioner may bias the inner actuation contact surface 2043 laterally outward (and thereby hingedly bias the inner tool contact surface 2038 laterally inward) by translating the translating member 2050 in the first translation direction X1. In the illustrated embodiment, the first translational direction X1 is in the proximal direction.

The attachment means 2034 may comprise a ratchet configured to prevent the arms 2036 from moving laterally outward after clamping the arms 2036 to the tool body 2021. The ratchet can include ratchet teeth 2058 that are linearly disposed along one or more ratchet racks on the exterior of the translating member 2050. The ratchet may include one or more pawls 2060 configured to engage the ratchet teeth 2058 in a manner that allows translation of the translating member 2050 in a first translation direction X1 while preventing translation in a second translation direction X2 opposite the first translation direction X1. One or more pawls 2060 may rotate along pawl axes 2063, respectively. One or more of the pawls 2060 may each include a tab that allows manual disengagement of the pawl 2060 from the ratchet teeth 2058.

As shown in fig. 30, 32 and 33, the coupling element 2016 of the present embodiment can define a mounting bracket 2017 configured to releasably mount with a field generator. The coupling element 2016 may define a lateral access opening 2132 similar to the lateral access openings described above. Referring now to fig. 33, the coupling element 2016 may include a shaft mount 2186 having a recess 2187 in which the shaft 2006 may be seated when the shaft 2006 is also fully seated within the opening 2132. The shaft mount 2186 may include a bearing surface 2190 within the recess 2187. In this embodiment, the shaft mount 2186 may be a flexible link that couples the elements 2016. The shaft mount 2186 may include a button 2189 that may be manually depressed to bend (such as downward) the shaft mount 2186 in a manner that allows the shaft 2006 to be guided into the recess 2187 by the opening 2132. When the button 2189 is released, the shaft mount 2186 flexes (such as upward) to a position where the shaft 2006 is fully seated within the recess 2187 and engaged with the bearing surface 2189.

It should be appreciated that the coupling elements 16, 1016, 2016 disclosed herein represent non-limiting examples of coupling elements that may be used to couple a shaft lateral access to a field generator.

Referring now to fig. 34 and 35, the coupling element 2016 may include a linkage, such as one or more transverse pins 2168 extending within a pair of receivers 2140 on a proximal side of the coupling element 2016. The distal ends of the branches may define coupler recesses 2112 configured to receive the transverse pins 2186 in a manner that generally rigidly couples the bridge 2020 to the coupling element 2016.

Referring now to fig. 36-39, another embodiment of a distal targeting device 3002 is shown. As shown in fig. 36, the distal targeting device 3002 may include a bridge 3020 having a branch 3028 coupled to the field generator 3014. The field generator 3014 has a lateral access opening 3132 for receiving a shaft of a power tool 3004 coupled to the distal targeting device 3002. The shaft mount may be located substantially at the geometric center of the field generator 3014. In this embodiment, the branches 3028 are cradled on opposite lateral sides of the power tool 3004 by the attachment means 3034 of the bridge 3020. The attachment device 3034 may include a tether 3040. The branch 3028 may include a coupling, such as a cleat 3030, extending laterally outward from the branch 3028, such as at a proximal portion of the branch 3028. The tether 3040 is configured to be coupled to the stud 3030 to couple the branch 3028 to the attachment device 3024. Fig. 36 shows the tether 3040 loosely cinched to the stud 3030, while fig. 37 shows the tether in a taut configuration.

The attachment device 3034 includes a mounting bracket 3070 configured to be attached to a portion of a power tool, such as the motor fairing top. The mounting bracket 3070 may be configured to anchor the tether 3040. The tether 3040 may extend from the tensioning mechanism 3050. The tensioning mechanism 3050 may be releasably attached to the mounting bracket 3070. The tensioning mechanism 3050 can include a turntable 3052 rotatably coupled to the base 3054. The mount 3070 may define a mount surface 3055 for supporting the base 3054 of the tensioning mechanism 3050. The mounting bracket 3070 may also include a first coupling element, such as a tab 3060 configured to releasably couple to the base 3054 in a snap-fit manner.

As shown in fig. 36, the turntable 3052 can define an axis of rotation 3053. The turntable 3052 can be coupled to an inner spool on which the tether 3040 is wound. The tensioning mechanism 3050 may be configured such that rotating the spool (via the turntable 3052) about the axis 3053 in a first rotational direction relative to the base 3054 causes the tether 3040 to further wrap around the spool, which imparts tension to the tether 3040 and reduces the overall length of the tether 3040 extending from the tensioning mechanism 3050. The tensioning mechanism 3050 can include a ratchet, thereby preventing the spool and/or turntable 3052 from rotating in a second rotational direction opposite the first rotational direction when the ratchet is engaged. The ratchet can be engaged and disengaged, for example, by subsequently depressing the dial 3052.

As shown in fig. 39, the mount 3070 can define a second coupling element, such as an anchor slot 3080 recessed from the mount surface 3055. The most distal one of the anchor slots 3080 may be at least partially defined by the front tab 3065. The anchor slot 3080 may be configured to receive a portion of the tether 3040. For example, the tether may be withdrawn or at least loosened from the tensioning mechanism 3050 and wrapped through one or more and optionally all of the anchor slots 3080 and around one or more and optionally all of the cleats 3030 in a manner that anchors the branch 3028 to the mounting bracket 3070. The tensioning mechanism 3050 may be coupled to the mounting bracket surface 3055 of the mounting bracket 3070 by a snap fit through tabs 3060. The mounting bracket surface 3055 may be inclined distally at an acute angle α relative to the shaft axis 18 (see fig. 1) to enhance physician access. The dial 3052 may then be rotated in a first rotational direction until the tether 3040 rigidly ties the branch 3028 to the power tool 3004. As shown in fig. 38, the branches 3028 of the present embodiment are laterally adjustable as needed to accommodate power tools 3004 of different sizes and/or shapes. In this embodiment, the branch 3028 itself may be characterized as the gripping arm of the attachment means 3024.

Referring now to fig. 40-42, an example embodiment of a display assembly 300 for use with a distal targeting device as described above will now be described. As shown in fig. 40, the display assembly 300 may include a display 302 coupled to an arm, such as an articulating arm 304, as shown. The articulating arm 304 may be formed from a plurality of articulatable arm segments 306 coupled together. The arm 304 may also include an anchor section 308 for connection to a distal targeting device. As shown in fig. 41, the display 302 may include a viewing screen 301 that provides, as a non-limiting example, visual indicia 310 of the relative positions of the distal end of the shaft 6 and an item targeted by the distal targeting device (such as a locking screw of an intramedullary nail). As shown in fig. 42, the display assembly 300 may be coupled to the bridge 20 of the distal targeting device 2. In other embodiments, the display assembly 300, or at least the display 302, may be coupled to another location within the surgical table, workstation, or physician's field of view during distal targeting.

Although the present disclosure has been described in detail, it should be understood that various changes, substitutions and alterations can be made hereto without departing from the spirit and scope of the invention as defined by the appended claims. Furthermore, the scope of the present disclosure is not intended to be limited to the specific embodiments described in the present specification. Those of ordinary skill in the art will readily appreciate that processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present disclosure.

Claims (16)

1. A distal targeting device for a surgical instrument, comprising:

a field generator having a coupling element configured to receive a shaft elongated along an axis; and

a bridge connectable to the field generator to be spaced from the field generator in a proximal direction relative to the axis, the bridge having an attachment device connectable to a tool configured to manipulate the shaft, the bridge having a pair of arms configured to clasp a body of the tool in a manner that rigidly couples the bridge to the tool, wherein at least one of the arms is positionable at an adjustable distance relative to the attachment device such that the arm is rigidly claspable to a tool body having one or more of a variety of shapes and sizes.

2. The distal targeting device of claim 1, wherein at least one of the pair of arms defines a rack having teeth, and the attachment device comprises a pinion configured to engage the teeth of the rack such that rotation of the pinion causes the distance to increase or decrease.

3. The distal targeting device of claim 2, wherein the pinion is coupled to a knob configured to allow a physician to manipulate the pinion.

4. The distal targeting device of claim 3, wherein the knob defines a ratchet tooth and the attachment device includes at least one pawl configured to engage the ratchet tooth such that the at least one pawl is configured to: 1) Allowing the pinion to rotate about a first rotational direction to reduce the distance, and 2) preventing the pinion from rotating about a second rotational direction opposite the first rotational direction.

5. The distal targeting device of claim 1, wherein the attachment device comprises a tether engaged with a tensioning mechanism, the tether configured to attach to at least one of the arms, and the tensioning mechanism configured to apply tension to the tether to reduce the distance.

6. The distal targeting device of claim 5, wherein each of the pair of arms defines one or more cleats and the tether is configured to tighten around the one or more cleats of each of the arms to attach the tether to each of the arms and the tensioning mechanism is configured to apply tension to the tether to reduce the distance.

7. The distal targeting device of claim 6, wherein the tensioning mechanism comprises a dial, and the tether is wound around a spool connected to the dial such that rotation of the dial applies the tension to the tether.

8. The distal targeting device of claim 1, wherein the attachment device comprises a translatable member translatable along a translation axis, the translatable member having a member contact surface, at least one of the arms defining an arm contact surface engaged with the member contact surface, and at least one of the member contact surface and the arm contact surface being oriented at an oblique angle relative to the translation axis such that translation of the translatable member along the translation axis in a first translation direction causes at least one of the arms to move to reduce the distance.

9. The distal targeting device of claim 8, wherein the translatable member defines ratchet teeth, and the attachment device comprises at least one pawl engaged with the ratchet teeth, the at least one pawl configured to: 1) Allowing the translatable member to translate in the first translation direction, and 2) inhibiting the translatable member from translating in a second translation direction opposite the first translation direction.

10. The distal targeting device of claim 8, wherein at least one of the arms comprises a first arm portion configured to abut the body of the tool and a second arm portion defining the arm contact surface, and wherein at least one of the arms is pivotable about a pivot joint between the first arm portion and the second arm portion such that reducing the distance causes the first arm portion to pivot against the body of the tool.

11. The distal targeting device of claim 1, wherein at least one of the arms is connected to the attachment device by a spring hinge configured to bias the at least one of the arms against the body of the tool.

12. The distal targeting device of claim 11, wherein each of the pair of arms is connected to the attachment device by a respective spring hinge configured to bias the pair of arms against opposite sides of the body of the tool.

13. The distal targeting device of claim 12, wherein the bridge further comprises a second pair of arms configured to clasp the body of the tool in series with the pair of arms in a manner that rigidly couples the bridge to the tool, each of the pair of arms and the second pair of arms being positionable at an adjustable distance relative to the attachment device such that the arms can rigidly clasp tool bodies having one or more of a variety of shapes and sizes, and each of the second pair of arms being connected to the attachment device by a respective spring hinge configured to bias the second pair of arms against the opposite side of the body of the tool.

14. A distal targeting system, comprising:

a power tool having a tool body and a receiving member;

a shaft elongated along an axis extending in a longitudinal direction, a proximal portion of the shaft receivable in the receiving element;

a field generator having a coupling element configured to receive the shaft; and

a bridge connectable to the field generator to be spaced from the field generator in a proximal direction relative to the axis, the bridge having an attachment device connectable to the power tool, wherein the bridge comprises a pair of arms configured to clasp the tool body in a manner that rigidly couples the bridge to the power tool, wherein at least one of the arms is positionable at an adjustable distance relative to the attachment device such that the arm is capable of 1) rigidly clasp the tool body, 2) releasing the tool body, and 3) rigidly clasp a second tool body having one or more of a different size and shape than the tool body.

15. The distal targeting system of claim 14, wherein the attachment device comprises an actuator configured to reposition at least one of the arms to adjust the distance.

16. The distal targeting system of claim 14, wherein the field generator further comprises a link, the bridge further comprises one or more couplers at a distal end of the bridge, and the link is releasably connectable to the one or more couplers of the bridge.