Surgical tool handle assembly

A handle assembly is disclosed for firmly holding a surgical tool. The handle assembly comprises a handle and a locking mechanism attached to the handle. The locking mechanism includes a locking ring, a collet, and a compressible locking pin engageable with the locking ring and collet. The locking ring is moveable between first and second positions relative to the handle. The first position is an unlocked position whereby the locking pin is in a decompressed state relative to the locking ring and the collet. In the first position, a surgical tool may be inserted and withdrawn from the collet of the locking mechanism. The second position is a locked position whereby the locking pin is in a compressed state relative to the locking ring and the collet. In the second position, a surgical tool is anchored in the collet of the locking mechanism.

BACKGROUND OF THE DISCLOSURE

The present disclosure relates generally to a handle for a surgical tool. Specifically, the present disclosure relates to a handle for releasably receiving a surgical tool such as an osteotome and the like.

An osteotome or similar surgical tool is a chisel-like instrument used to cut or divide bone. Conventional handles for holding and manipulating surgical tools, such as osteotomes for the knee and other body parts, do not always provide secure gripping or firm grasping of the surgical tool. That is, the surgical tool is not rigidly connected to the handle or has too much play relative to the handle, thereby resulting in wobbling or other movement of the tool. Consequently, such play can adversely affect control or effectiveness of the tool and ultimately the precision of the surgical procedure being performed.

BRIEF SUMMARY OF THE DISCLOSURE

In accordance with an exemplary embodiment, there is provided a handle assembly for receiving a surgical tool. The handle assembly comprises a handle and a locking mechanism attached to the handle. The locking mechanism includes a locking ring, a collet, and a compressible locking pin engageable with the locking ring and collet. The locking ring is moveable between first and second positions relative to the handle.

An aspect of the exemplary embodiment is that the collet is mounted within the handle and includes a flexible portion moveable between a first position and a second position. When the locking ring moves from the first position to the second position, the flexible portion of the collet moves from the first position to the second position. Further, the compressible locking pin is between the locking ring and the collet. The compressible locking pin includes at least one of nylon, polytetrafluoroethylene, ultra-high molecular weight polyethylene, polyetherimide, or glass.

Another aspect of the exemplary embodiment is that the locking mechanism further includes a retaining ring having a through hole for receiving the locking pin. The locking pin is mounted in the through hole and oversized relative to a size of the through hole. Additionally, the locking pin is mounted in the through hole and has an overall height greater than an overall height of the retaining ring, and the locking mechanism includes a cam for camming against the locking pin.

In accordance with an exemplary embodiment, there is provided a handle assembly for receiving a surgical tool. The handle assembly comprises a handle having a tapered receiving cavity, and a locking mechanism attached to the handle and received within the tapered receiving cavity. The locking mechanism includes a locking ring moveable between first and second positions relative to the handle, a retaining ring, a collet, and a locking pin mounted to the retaining ring and positioned between the locking ring and collet.

An aspect of the exemplary embodiment is that the retaining ring, collet and locking pin are within the tapered receiving cavity. The locking ring includes a cam for camming against the locking pin. Each of the locking ring, retaining ring and collet includes a central through hole for receiving a surgical tool.

Another aspect of the exemplary embodiment is that the locking mechanism further includes a plate between the locking ring and collet, and the locking pin directly engages the locking ring and plate. The locking mechanism further includes a biasing member biasing the collet, and the collet directly engages a tapered wall of the tapered receiving cavity. The locking pin is a deformable locking pin and the collet is a flexible collet.

Other features and advantages of the subject disclosure will be apparent from the following more detailed description of the exemplary embodiments.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The foregoing summary, as well as the following detailed description of the exemplary embodiments of the subject disclosure, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the present disclosure, there are shown in the drawings exemplary embodiments. It should be understood, however, that the subject application is not limited to the precise arrangements and instrumentalities shown.

FIG. 1Ais a perspective view of a handle assembly for receiving a surgical tool in accordance with an exemplary embodiment of the subject disclosure;

FIG. 1Bis an exploded view of the handle assembly ofFIG. 1A;

FIGS. 2A-Bare perspective views of a locking ring of the handle assembly ofFIG. 1A;

FIGS. 3A-Bare perspective views of a retaining ring of the handle assembly ofFIG. 1A;

FIGS. 4A-Bare various views of a central ring of the handle assembly ofFIG. 1A;

FIG. 5is a perspective view of a collet of the handle assembly ofFIG. 1A;

FIG. 6is a partial longitudinal cross-sectional view of the handle assembly ofFIG. 1A;

FIGS. 7A-Bare various views of a locking ring and central ring of the handle assembly ofFIG. 1Ain an unlocked position with certain components omitted and in phantom for purposes of illustration; and

FIG. 8is a top cross-sectional view of a locking ring and central ring of the handle assembly ofFIG. 1Ain a locked position with certain components omitted for purposes of illustration.

DESCRIPTION OF THE INVENTION

Reference will now be made in detail to the exemplary embodiments of the subject disclosure illustrated in the accompanying drawings. Wherever possible, the same or like reference numbers will be used throughout the drawings to refer to the same or like features. It should be noted that the drawings are in simplified form and are not drawn to precise scale. In reference to the disclosure herein, for purposes of convenience and clarity only, directional terms such as top, bottom, above, below and diagonal, are used with respect to the accompanying drawings. The term “distal” shall mean away from the center of a body. The term “proximal” shall mean closer towards the center of a body and/or away from the “distal” end. With reference to a handle assembly, the “distal end” of the present handle assembly refers to the end of the assembly towards the locking mechanism and the “proximal end” of the present handle assembly refers to the end of the assembly away from the locking mechanism. Such directional terms used in conjunction with the following description of the drawings should not be construed to limit the scope of the subject disclosure in any manner not explicitly set forth. Additionally, the term “a,” as used in the specification, means “at least one.” The terminology includes the words above specifically mentioned, derivatives thereof, and words of similar import.

“Substantially” as used herein shall mean considerable in extent, largely but not wholly that which is specified, or an appropriate variation therefrom as is acceptable within the field of art.

Furthermore, the described features, advantages and characteristics of the exemplary embodiments of the subject disclosure may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize, in light of the description herein, that the subject disclosure can be practiced without one or more of the specific features or advantages of a particular exemplary embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all exemplary embodiments of the present disclosure.

Referring now to the drawings,FIGS. 1A and 1Billustrate a handle assembly10for receiving an unillustrated surgical tool such as a knee osteotome or any other surgical tool requiring a stable connection with a handle to facilitate tool manipulation. The handle assembly comprises a handle12and a locking mechanism14attached to the handle.

The handle12is an ergonomically shaped handle adapted to be comfortably grasped by a hand of a user. The handle12has a proximal end12a,a distal end12badjacent the locking mechanism14, and a contoured intermediate portion12cbetween the proximal and distal ends12a,12b.As best seen inFIG. 6, the handle12has a tapered receiving cavity30extending from its distal end. The tapered receiving cavity includes a counterbore section41and a tapered wall42.

Referring back toFIG. 1B, the locking mechanism14includes a locking ring16, a collet18, and a deformable or compressible locking pin20engageable with the locking ring and collet, as further discussed below. The locking mechanism is attached to the handle12and received within the tapered receiving cavity30of the handle. Referring toFIGS. 1B and 6, the locking mechanism further includes a retaining ring24, a central ring44, a plate38between the locking ring and the collet, and a biasing member40biasing the collet. Specifically, the locking mechanism is secured to the handle by connection of the central ring's legs84lockingly engaging the retaining band96, as further discussed below.

The locking ring16is configured as shown, e.g., inFIGS. 1A, 1B, 2A, 2B, and 6. The locking ring includes a distal end64and a proximal end66. In accordance with the exemplary embodiment, the locking ring includes a central counterbore or cylindrical indentation59adapted to receive the central ring44. The locking ring includes a central through hole82in the cylindrical indentation for receiving a surgical tool. As shown inFIGS. 2A and 2B, the central through hole82is illustrated as substantially cross-shaped, although the central through hole may be shaped in any other shape suitable for receiving a surgical tool, such as a triangular, square, pentagonal, hexagonal, heptagonal, or octagonal through hole.

The locking ring also includes one or more guide through holes62. The guide through holes62are adapted to receive one or more guide legs84of the central ring44through the locking ring, as further discussed below. In some aspects, the guide through holes62are curved along a circumference of the central indentation59and disposed opposite each other on either side of the central indentation.

Referring toFIG. 2B, the locking ring16also includes a cam28. The cam is disposed about the undersurface of the locking ring for camming against the locking pin20. The cam is configured, e.g., as a curved ramp that extends distally from the proximal end surface. That is, the cam extends further than the main undersurface of the locking ring.

The locking ring also includes a bore or opening50for receiving a button lock52and a position indicator60to indicate whether the locking ring is in a first or second position relative to the handle12. The locking ring further includes scalloped edges58. The scalloped edges are concave edges and adapted to facilitate rotating or twisting the locking ring from the first to the second position and back again.

The locking ring is moveable between first and second positions relative to the handle12. Specifically, the locking ring is operable to lock and unlock the surgical tool to the handle.FIGS. 7A and 7Billustrate the first position andFIG. 8illustrates the second position of the locking ring. The first position is an unlocked position and the second position is a locked position, respectively.

The collet18is configured as shown, e.g., inFIGS. 1B and 5. The collet includes a distal end90and a proximal end92. The distal end includes a main body portion21and the proximal end includes a tapered flexible portion22. In accordance with the exemplary embodiment, the collet is formed from a single piece of material. The collet is formed in an accordion-like fashion along a length of the collet so as to form a plurality of slits extending along the length of the collet along with a central through hole36. The plurality of slits provide a cage-like structure to the collet. Due to the plurality of slits, the tapered flexible portion is deformable and flexible, e.g., moveable between a first position (e.g., an uncompressed position) and a second position (e.g., a compressed position). The first position of the collet is also a surgical tool receiving position and the second position of the collet is also a surgical tool locking position. The central through hole36is configured to receive the surgical tool. When mounted to the handle12, the collet directly engages the tapered wall42of the tapered receiving cavity30. The collet may be formed from a hard metal such as steel or any other hard metal suitable to be machined so as to be deformable and flexible. Due to the overall configuration and flexibility of the collet, the central through hole diameter can be changed between a first diameter and a second diameter smaller than the first diameter so as to securely engage a tool therein. In other words, the overall diameter of the collet changes between a first diameter and a second diameter when the collet moves between the first and second positions respectively.

The locking pin20is a deformable or compressible locking pin. That is, the locking pin while rigid can have its overall dimension changed upon application of forces applied to it by the locking ring16as further discussed below, and which is resilient enough to return to substantially its original shape and dimensions upon removal of the application of forces. The locking pin can be configured as best shown inFIGS. 1B and 6. In the present exemplary embodiment the locking pin includes a main body23and an anchor portion25, as shown inFIG. 6. The anchor portion25has a smaller diameter than that of the main body23. According to an aspect, there is at least one compressible locking pin20. In further aspects, there may be two or more locking pins as shown inFIG. 1B. The locking pin is oversized relative to the size of a through hole26in the retaining ring24. For example, the locking pin is oversized with an overall height greater than an overall height of the through hole26and greater than an overall height of the retaining ring24. The number of locking pins may correspond to the number of through holes26of the retaining ring24and the number of cams28of the locking ring16. The locking pin directly engages the locking ring16and the plate38of the locking mechanism14.

The compressible locking pin20may be formed from generally compressible polymers or elastomers. Examples of generally compressible polymers or elastomers can include, but are not limited to, a suitably hard polymer such as nylon, polytetrafluoroethylene (PTFE), glass-filled PTFE, ultra-high molecular weight polyethylene such as Tivar®, polyetherimide such as Ultem®, a glass, or any combination of the foregoing. In accordance with the exemplary embodiment, the locking pin is formed from 25% glass-filled PTFE. For example, the locking pin may have a modulus of elasticity of about 1700 N/mm2or a Shore hardness of about 65 Shore D. Advantageously, such material exhibits a low coefficient of friction that facilitates the sliding interaction of the locking pin with the cam28of the locking ring16, as further discussed below.

The retaining ring24is configured as shown, e.g., inFIGS. 3A, 3B, and 6. The retaining ring has a distal end68and a proximal end74. In accordance with the exemplary embodiment, the proximal end is tapered relative to the distal end. The retaining ring includes a central through hole34for receiving the surgical tool. As shown inFIGS. 3A and 3B, the central through hole34is illustrated as substantially cross-shaped, although the central through hole34may be shaped in any other shape suitable for receiving a surgical tool, such as a triangular, square, pentagonal, hexagonal, heptagonal, or octagonal through hole.

The distal end68of the retaining ring24is also configured to include a recessed track35, and preferably two recessed tracks35,35′. The number of recessed tracks is chosen to match the number of recessed cams28on the locking ring16. The recessed track is sized and shaped to receive the cam28therein such that a bottom-most end of the cam is closely adjacent to or slidingly engages the bottom floor of the recessed track.

Positioned along the recessed track35is a through hole26for receiving the locking pin20into and through the through hole. The through hole26has a larger diameter portion toward the distal end of the retaining ring and a smaller diameter portion toward the proximal end, i.e., the through hole can be sloped.

The retaining ring includes at least one indentation70configured to receive one or more guide legs84of the central ring44through the retaining ring, as further discussed below. The indentation includes a flange73for mating engagement with the recess85of the one or more guide legs84of the central ring44. The retaining ring also includes a retaining track71. The retaining track71defines an annular recess for receiving the retaining band96.

The retaining ring includes one or more plunger bores72. The plunger bores72are adapted receive the plunger98and the biasing member100, as shown inFIG. 1B.

The central ring44is configured as shown, e.g., inFIGS. 1A, 1B, 4A, 4B, and 8. The central ring includes a distal end76and a proximal end86. In accordance with the exemplary embodiment, the proximal end includes one or more legs84. The legs extend proximally from the central ring. The legs are tapered toward the proximal end and disposed opposite each other. The legs include a retaining track80and a recess85. The retaining track80is adapted to receive the retaining band96. The retaining band96is adapted to engage the retaining track71of the retaining ring24and the retaining track80of the legs84, so that the retaining ring24and the central ring44remain in place relative to each other. The recess85is configured for mating engagement with the flange73of the retaining ring24. The central ring includes a central through hole32for receiving a surgical tool. As shown inFIGS. 4A and 4B, the central through hole32is illustrated as substantially cross-shaped, although the central through hole may be shaped in any other shape suitable for receiving a surgical tool, such as a triangular, square, pentagonal, hexagonal, heptagonal, or octagonal through hole.

The central ring44includes one or more status indicators88a,88bthat operate in concert with the position indicator60on the locking ring16to indicate whether the locking ring is in the first or second position, as further described below. The central ring also includes a bore or opening78that is sized and adapted to receive the pin46and the biasing member48, as shown inFIG. 1B.

Referring toFIGS. 1B and 6, the plate38is disposed between the locking ring16and the collet18. The plate is configured as a washer having a central through hole for receiving the surgical tool. The plate is sized to mount within the handle12.

The biasing member40is configured as shown, e.g., inFIGS. 1B and 6. In accordance with the exemplary embodiment, the biasing member40may be a compression spring, as shown, or any other suitable biasing member such as an elastomer, leaf spring, plastic, and the like. The biasing member exerts a biasing force distally to bias the collet18towards the locking ring16.

The plunger98and the biasing member100are configured as shown, e.g., inFIG. 1B. The plunger and biasing member work in concert to exert a biasing force distally against the locking ring16and the central ring44. This biasing force acts to stabilize the handle assembly10upon insertion of a tool.

Referring toFIGS. 1B and 6, the retaining ring24, the plate38, the collet18, and the biasing member40are all assembled into the tapered receiving cavity30of the handle12. The biasing member40is seated with the bottom end of the tapered receiving cavity30. The collet18is disposed distal to or on top of the biasing member and directly engages the biasing member. The plate38is disposed distal to the collet18and between the collet and the retaining ring24, and directly engages the collet.

The locking pin20is positioned between the locking ring16and the plate38. In accordance with the exemplary embodiment, the locking pin is mounted in the through hole26of the retaining ring24. Due to the overall size of the locking pin, a portion of the top of the locking pin extends proud of the uppermost end of the through hole26, and a portion of the bottom of the locking pin extends out from the bottom-most end of the through hole and retaining ring.

The plunger98and the biasing member100are also inserted into the plunger bore72of the retaining ring24. The button52is inserted radially inwardly into the bore or opening50of the locking ring16. The locking ring16is disposed distal to the retaining ring24.

Due to the oversizing of the locking pin20, the locking pin directly engages the cam28when the locking ring is moved from its first position to its second position.

The biasing member48and the pin46are inserted radially inwardly into the bore or opening78of the central ring44. The central ring44is seated within the cylindrical indentation59of the locking ring16. Specifically, the legs84of the central ring44are inserted into and through the guide through holes62and into mating engagement with the indentations70of the retaining ring24. Lastly the retaining band96is inserted into the retaining track71of the retaining ring24and the retaining track80of the central ring44. In this regard, the arrangement of the central ring44, the locking ring16, the retaining ring24, and the collet18are adapted to bring each central through hole82,34,36,32into alignment with each other, thereby allowing the handle assembly10to receive a surgical tool smoothly into and through each through hole.

In operation,FIGS. 7A, 7B, and 8illustrate how the locking ring16assumes the first and second positions to receive and then anchor the surgical tool in the locking mechanism14. When the locking ring is in the first position (e.g., the unlocked position), a user (e.g., a surgeon or other medical provider) may insert a surgical tool into and through the central through holes32,34,36,82of the central ring44, the locking ring16, the retaining ring24, and the collet18, respectively.

Once the surgical tool is properly inserted into the locking ring, retaining ring, and the collet, the user rotates the locking ring16to the second position (e.g., the locked position), as shown inFIG. 8. Referring toFIG. 6, when the user rotates the locking ring, the cams28cam against the upper surfaces of the locking pins20, thereby causing the bottom surfaces of the locking pins to press against the plate38situated beneath the retaining ring24. The proximal end of the plate, in turn, presses against the distal end90of the collet18, thereby causing the flexible portion22of the collet to be pushed proximally against the tapered wall42of the tapered receiving cavity30. The proximally-directed force on the collet forces the flexible portion of the collet to flex inwardly against the surgical tool, exerting a tight grip on the surgical tool to lock the surgical tool relative to the handle assembly10. The proximally-directed force on the collet also biases the collet proximally, counter to the biasing force exerted by the biasing member40, thereby compressing the biasing member.

When the retaining ring24is sufficiently turned to the second position such that the lowest portions of the cams28are in contact with and camming against the upper surfaces of the locking pins20, the greatest force is translated from the locking pins20to the collet18via the plate38. In the second position, the locking ring16locks relative to the center ring44, thereby locking the surgical tool in position. Referring toFIG. 8, in order to maintain the locking ring16locked relative to the center ring44, when moved to the second position, the pin46is biased radially outwardly such that the radially outermost portion of the pin is received in a bore or opening50provided on the locking ring16. When received in the bore50, the pin46is partially within the locking16and the center ring44, thereby preventing rotation of the locking ring16relative to the center ring44. In this position, the surgical tool is both anchored to and locked in the locking mechanism14.

Referring toFIG. 8, when it is desired to unlock and release the surgical tool from the locking mechanism14, a user depresses the button lock52that is radially disposed on the locking ring16. Depressing the button lock allows the locking ring to move from the second position (e.g., the locked position) to the first position (e.g., the unlocked position), shown inFIGS. 7A and 7B. As shown inFIG. 8, the radially innermost end54of the button lock52is contacted by the radially outermost end56of the pin46. Pushing the button lock52radially inwardly moves the pin46radially inwardly counter to the radially outward biasing force of the biasing member48. At the point at which the radially outermost end56of the pin46is pushed out of the bore50by the button lock52, the locking ring16is free to rotate relative to the center ring44. Referring toFIGS. 7A and 7B, the user may then rotate the locking ring16to return to the first position (e.g., the unlocked position) relative to the center ring44. Although shown in accordance with the exemplary embodiment as being turned in a counterclockwise direction to the first position, in accordance with other aspects the locking ring16may be turned clockwise to the first position, depending on the direction of slope of the cams28on the undersurface of the locking ring16.

As the locking ring24is moved from the second position (e.g., the locked position) shown inFIG. 8to the first position (e.g., the unlocked position) shown inFIGS. 7A and 7B, the locking pins20decompress as they are free from camming engagement with the cams28. As the locking pins decompress, they exert a reduced force on the plate38which, in turn, reduces the force exerted by the flexible portion22of the collet18against the surgical tool. The reduced force on the plate also reduces the force exerted by the collet against the biasing member40, thereby allowing the biasing member to bias the collet distally toward the locking ring16. When the locking ring reaches the first position, the force exerted by the locking pins on the plate38is essentially minimal. In such a state, the flexible portion22of the collet18relaxes from clamping engagement with the surgical tool, whereby the surgical tool may be readily extracted from the locking mechanism14.

The exemplary embodiments of the handle assembly discussed herein provide numerous advantages over conventional surgical tool handles. For example, the handle assembly10eliminates play of the surgical tool within the handle. The handle assembly thus greatly enhances user control of the knee osteotome or other surgical tool during a surgical procedure. Further, it is to be understood that while the present disclosure is useful for firmly holding a knee osteotome, the handle assembly disclosed herein is equally suitable to firmly holding different types of surgical tools or other tools.