WO2019192793A1

WO2019192793A1 - Surgical rotational tool driver and method

Info

Publication number: WO2019192793A1
Application number: PCT/EP2019/055442
Authority: WO
Inventors: James Anderson; Ian FLATTERS; David Horne
Original assignee: Depuy Ireland Unlimited Company
Priority date: 2018-04-06
Filing date: 2019-03-05
Publication date: 2019-10-10
Also published as: GB201805794D0

Abstract

A surgical rotational tool driver and a method of operating the same. The driver includes a hollow shaft having a proximal end, a distal end and at least one bend. The driver includes a hollow driveline extending within the shaft. The driveline has a universal joint located at each bend. The driveline has a proximal end connectable to a rotational power tool for applying torque. The driveline has a head part extending distally from the distal end of the shaft. The head part includes connection features for connecting to a surgical rotational tool. The connection features include a release mechanism for releasing the head part from the surgical rotational tool. The driver includes an actuation member extending within the substantially hollow driveline. The actuation member is connected to the release mechanism for operating the release mechanism at a position located proximally with respect to the head part.

Description

SURGICAL ROTATIONAL TOOL DRIVER AND METHOD

FIELD OF THE INVENTION This invention relates to a surgical rotational tool driver. This invention also relates to a method of operating a surgical rotational tool driver.

BACKGROUND OF THE INVENTION Surgical rotational tool drivers allow torque to be transmitted to a surgical rotational tool from a rotational power tool. An example of a surgical rotational tool driver is an acetabular reamer driver for use with an acetabular reamer.

Hip replacement is a surgical procedure in which the hip joint is replaced by a prosthetic implant. As part of a hip replacement procedure, an acetabulum of the patient may be prepared for receiving an acetabular cup implant by reaming it to an appropriate size and depth. An acetabular reamer may have a substantially hemispherical dome to be received in the acetabulum. The acetabular reamer may also include features located on an outer surface of the dome for grating the inner surface of the acetabulum as the reamer rotates. The acetabular reamer may be releasably attached to a distal end of an acetabular reamer driver, to allow the surgeon to manipulate it (e.g. to position the dome within the acetabulum and to apply a force for pressing the reamer against the inner surface of the acetabulum as the reamer rotates). A driveline may extend within the acetabular reamer driver for transmitting torque to the acetabular reamer.

The acetabular reamer driver may include a release mechanism for releasing the acetabular reamer from the acetabular reamer driver.

WO 2018/033788 A1 describes a surgical reamer driver device that provides a fully closed tube which prevents the invasion of debris and minimizes abrasion of soft tissue during use. The reamer device includes a minimum number of component assemblies, so as to permit easy replacement and minimize wear. The surgical reamer driver has a housing assembly in a stand-alone, assembled unit, a transmission drive train in a stand-alone, assembled unit enclosed in the housing assembly, and having at least one double universal joint and a surgical tool connector at the distal end thereof, a motor shaft coupling in a standalone, assembled unit at the proximal end thereof, and a handle assembly in a stand-alone, assembled unit at the proximal end thereof, these four basic components forming a driver which in a fully assembled state effectively prevents debris from access in the inner workings of the driver. A method for disassembling the reamer driver includes the steps of: a. actuating a sliding release sleeve to unlock the handle assembly from the housing assembly, thereby permitting the de-encapsulation of the drive train within the housing assembly; b. sliding the handle assembly off of the housing thereby effectively de-encapsulating the drive train; c. pulling the motor shaft coupling out of the housing thereby freeing the drive train from axial constraint on one end; d. unsnapping the drive train on the one end and lifting the one end out of the housing assembly thereby permitting removal of the drive train; and e. pulling the drive train out of the housing assembly, thus removing the drive train from the housing assembly.

WO 2017/029546 A2 describes a system, method and/or reamer driver device provides a fully closed tube which prevents the invasion of debris and minimizes abrasion of soft tissue during use. The reamer device includes a minimum number of component assemblies, so as to permit easy replacement and minimize wear.

US 2013/331841 Al describes a reamer for use in minimally invasive hip replacement surgical approaches is provided. The reamer spindle includes an elongate housing portion that extends along a first axis and a neck or distal portion that extends along a second axis, wherein the second axis extends at an angle of between about 35 degrees and about 65 degrees relative to the first axis. A reamer head is removably connectable to the distal neck portion and has a surface configured to cut bone.

EP 2 954 860 A2 describes an orthopaedic reamer handle, comprising: a reamer portion configured to transmit torque to a reamer head; a driver portion connected to said reamer portion and configured to receive and transmit torque from a driver; and a drive train connecting said reamer portion and said driver portion and configured to transmit torque from said driver portion to said reamer portion, said drive train including: a first drive shaft having a first end and a second end, said first end being connected to said driver portion, said first drive shaft defining a first axis; a first intermediate connector having a first intermediate end and a second intermediate end, said first intermediate end being connected to said second end; an offsetting member having a third end and a fourth end, said third end being connected to said second intermediate end at an acute angle relative to said first axis, said offsetting member defining a second axis; and a second intermediate connector connecting said fourth end to said reamer portion at an acute angle relative to said second axis. WO 2009/091497 A2 describes a surgical instrument for use in minimally invasive surgery, or in open procedures with difficult to access surgical fields. The instrument includes a proximal handle which is connected proximally via a first joint, to a central portion. The central portion is connected distally via a second joint, to a distal effector. The handle is linked rotationally to the distal effector such as via a transmission shaft having two or more joints, such as universal joints, located within the regions of the first and second joints. The resulting instrument provides for full natural motion dexterity and control of the effector end with high precision whereby: 1) flexion of the handle flexes the effector; 2) rotation of the handle about the angle of flexion produces a corresponding rotation of the effector; and 3) opening and closing of the handle operates the effector.

EP 2 692 302 A2 describes a minimally invasive surgical instrument having a shaft including an internal torque transmission member. The minimally invasive surgical instrument comprises a shaft, and an end effector connected to one end of the shaft. The shaft has at least one curved portion, and the at least one curved portion can transmit torque for operating the end effector in a rolling direction by means of a torque-transmission member therein.

SUMMARY OF THE INVENTION

Aspects of the invention are set out in the accompanying independent and dependent claims. Combinations of features from the dependent claims may be combined with features of the independent claims as appropriate and not merely as explicitly set out in the claims.

According to an aspect of the invention, there is provided a surgical rotational tool driver comprising:

a substantially hollow shaft having a proximal end, a distal end and at least one bend; and

a substantially hollow driveline extending within the hollow shaft, the driveline having:

a universal joint located at each the bend in the shaft;

a proximal end connectable to a rotational power tool for applying torque through the driveline;

a head part extending distally from the distal end of the shaft, the head part including connection features for connecting to corresponding connection features of a surgical rotational tool, the connection features including a release mechanism for releasing the head part from the surgical rotational tool; and

an actuation member extending within the substantially hollow driveline, wherein the actuation member is connected to the release mechanism for operating the release mechanism at a position on the surgical rotational tool driver located proximally with respect to the head part.

The provision of the actuation member within the driveline allows the release mechanism to be operated at a position that is located away from the distal end of the shaft. This may be more convenient for the surgeon, as the distal end of the shaft may not be easily accessible when it is located in the wound. Moreover, the provision of the actuation member within the driveline may allow an outer surface of at least the distal end of the shaft to be substantially free of clutter associated with the features (buttons, catches and the like) of a release mechanism, which may otherwise interfere with and damage soft tissue in the wound. In the absence of such features on its outer surface, the distal end of the shaft may thus have an uncluttered (e.g. smooth) and relatively narrow profile, which may also facilitate its easy insertion and extraction through the wound. The actuation member may be substantially flexible, to allow it to navigate the at least one bend in the shaft. The or each universal joint may include a substantially hollow central portion through which the actuation member extends. This may allow the actuation member to extend within the driveline without interfering with the operation of the driveline. For instance, the or each universal joint may connect an end of a driveline section of the driveline to an end of another driveline section of the driveline. The or each universal joint may include a spider part pivotally attached to the end of each driveline section; and an aperture in the spider part. The actuation member may extend though the aperture.

The surgical rotational tool driver may include an actuation mechanism located along the shaft for withdrawing the actuation member proximally within the driveline. As noted previously, the actuation member may allow an actuation mechanism of the surgical rotational tool driver to be located away from the distal end of the shaft. In one embodiment, the actuation mechanism may be located closer to the proximal end of the shaft than to the distal end of the shaft. In one embodiment, the shaft may include at least two bends located intermediate the distal end of the shaft and the actuation mechanism.

The actuation mechanism may include one or more openings located in a side wall of the substantially hollow driveline. The actuation mechanism may also include an inner sleeve mounted inside the driveline for rotation with the driveline. The inner sleeve may have one or more first members extending through respective ones of the opening(s) in the side wall of the driveline. The inner sleeve may include a central opening having an axial bearing surface within which the actuation member is rotationally received to allow rotation of the inner sleeve with the driveline and relative to the actuation member. For instance, the actuation member may remain substantially stationary. The actuation member may have a part having a radial dimension that is larger than a radial dimension of the central opening of the inner sleeve. The or each first member may be axially slideable within the respective opening(s) located in the side wall of the driveline to allow an edge of the central opening to urge against the part of the actuation member having a larger radial dimension to withdraw the actuation member proximally within the driveline. The actuation mechanism may include one or more openings located in a side wall of the substantially hollow shaft. The actuation mechanism may also include an intermediate sleeve mounted between an outer surface of the drive line and an inner surface of the shaft. The intermediate sleeve may have one or more second members extending through respective ones of the opening(s) in the side wall of the shaft. The intermediate sleeve may include a central opening having an axial bearing surface within which the driveline is rotationally received to allow rotation of the driveline while the intermediate sleeve remains substantially stationary. A part of the central opening may have an increased diameter to form a slot within which the end of the or each first member of the inner sleeve extending through the opening(s) located in the side wall of the driveline is rotationally received. The or each second member may be axially slideable within the respective opening(s) located in the side wall of the shaft to allow an edge of the slot to urge against the end of the or each first member to slide the inner sleeve axially to withdraw the actuation member proximally within the driveline.

The actuation mechanism may include an outer sleeve slideably mounted on an outer surface of the shaft. The outer sleeve may be connected to the or each second member for moving the intermediate member proximally to withdraw the actuation member proximally within the driveline.

The release mechanism may include one or more teeth receivable within openings of the corresponding connection features. The teeth may extend distally from a slideably moveable central shaft of the head part. The actuation member may be attached to the central shaft for withdrawing the teeth from the openings of the corresponding connection features by withdrawing the central shaft proximally by withdrawing the actuation member proximally.

The central shaft may be biased distally. This may allow the teeth of the release mechanism to be inserted and retained in the openings of the corresponding connection features, until the actuation member is withdrawn proximally.

The central shaft may include a central axial bearing surface within which the actuation member is rotationally received to allow rotation of the head part relative to the actuation member. This may allow the driveline and the actuation member to operate substantially independently of each other, so that, for instance, rotation of the driveline does not cause twisting or tangling of the actuation member inside the shaft. For instance, the actuation member may remain substantially stationary. The actuation member may comprise a substantially flexible tension member, such as a wire.

The actuation member may be a polymer. The actuation member may comprise an alloy.

The surgical rotational tool driver may be a reamer driver. For instance, the reamer driver may be an acetabular reamer driver. The surgical rotational tool may be an acetabular reamer. According to another aspect of the invention, there is provided a surgical kit comprising a surgical rotational tool driver of the kind set out above, and a surgical rotational tool having the corresponding connection features.

According to a further aspect of the invention, there is provided a method of operating a surgical rotational tool driver, the method comprising:

connecting one or more connection features of a head of a driveline of a surgical rotational tool driver to a surgical rotational tool, the surgical rotational tool driver comprising:

the driveline, wherein the driveline is substantially hollow and extends within the hollow shaft, the driveline having:

a universal joint located at each the bend in the shaft;

the head part, wherein the head part extends distally from the distal end of the shaft, the connection features including a release mechanism for releasing the head part from the surgical rotational tool; and an actuation member extending within the substantially hollow driveline, wherein the actuation member is connected to the release mechanism; and

using the actuation member to operate the release mechanism at a position on the surgical rotational tool driver located proximally with respect to the head part, to release the head part from the surgical rotational tool.

As noted above, operating the release mechanism at a position on the surgical rotational tool driver located proximally with respect to the head part may be more convenient for the surgeon, who does not need to access the distal end of the shaft (which may be located inside the wound) to effect the release of the surgical rotational tool from the surgical rotational tool driver. As also noted above, since the shaft need not be cluttered with distally located features of a release mechanism on an outer surface thereof, a method of using the surgical rotational tool driver during surgery may be easier to perform. The or each universal joint may include a substantially hollow central portion through which the actuation member extends. As noted above this may allow surgical rotational tool driver to be used without the actuation member interfering with the operation of the driveline. The or each universal joint may connect an end of a driveline section of the driveline to an end of another driveline section of the driveline and may include: a spider part pivotally attached to the end of each driveline section; and an aperture in the spider part. The actuation member may extend though the aperture.

The method may include connecting the proximal end of the driveline to a rotational power tool. The method may also include, prior to operating the release mechanism, applying torque through the driveline.

The substantially hollow driveline may rotate relative to the actuation member while torque is applied through the driveline. As noted above, this can prevent e.g. twisting or tangling of the actuation member. For instance, the actuation member may remain substantially stationary.

The method may include using an actuation mechanism located along the shaft for withdrawing the actuation member proximally within the driveline. As noted above, the actuation member may allow an actuation mechanism of the surgical rotational tool driver to be located away from the distal end of the shaft (e.g. the shaft may include at least two bends located intermediate the distal end of the shaft and the actuation mechanism).

The actuation member may comprise a substantially flexible tension member, such as a wire.

The surgical rotational tool driver may be a reamer driver.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention will be described hereinafter, by way of example only, with reference to the accompanying drawings in which like reference signs relate to like elements and in which:

Figure 1 shows a surgical rotational tool driver in accordance with an embodiment of the invention;

Figure 2A shows a cross section of the surgical rotational tool driver of Figure 1;

Figure 2B shows the surgical rotational tool driver of Figure 1 with a surgical rotational tool attached;

Figures 3 and 4 show the driveline of the surgical rotational tool driver of Figure 1 ;

Figure 5 shows a cross section of the driveline of the surgical rotational tool driver of Figure 1;

Figure 6 shows a cross section of the distal end of the surgical rotational tool driver of Figure 1;

Figure 7 shows a distal end of the driveline of the surgical rotational tool driver of Figure 1 ;

Figure 8 shows some of the features of a universal joint of the driveline of the surgical rotational tool driver of Figure 1;

Figure 9 shows a spider part of a universal joint of a driveline of the surgical rotational tool driver of Figure 1;

Figure 10 shows a cross section of an actuation mechanism of the surgical rotational tool driver of Figure 1 (the driveline is not shown in Figure 10);

Figure 11 shows another cross section of the actuation mechanism of the surgical rotational tool driver of Figure 1 ; and

Figure 12 shows a cut away view of the actuation mechanism of the surgical rotational tool driver of Figure 1 (the driveline is not shown in Figure 12). DETAILED DESCRIPTION

Embodiments of the present invention are described in the following with reference to the accompanying drawings.

Figure 1 shows a surgical rotational tool driver 10 in accordance with an embodiment of the invention. The surgical rotational tool driver includes a substantially hollow shaft 2. The substantially hollow shaft 2 may be elongate. The substantially hollow shaft 2 has a proximal end 4 and a distal end 6.

The substantially hollow shaft 2 includes at least one bend. Each bend is located along the substantially hollow shaft 2, intermediate the proximal end 4 and the distal end 6. In the present embodiment, the surgical rotational tool driver 10 is an offset driver including two bends 22, 24. It is envisaged however that the substantially hollow shaft 2 may include a single bend, or more than two bends.

In the present embodiment, the bend 22 is located distally with respect to the bend 24. Each bend may be located at the interface between two shaft sections of the substantially hollow shaft 2. For instance, in the present embodiment, the substantially hollow shaft 2 includes a distal shaft section 12, an intermediate shaft section 14 and a proximal shaft section 16. The distal shaft section 12 extends distally from the bend 22. The intermediate shaft section 14 extends between the bend 22 and the bend 24. The proximal shaft section 16 extends proximally from the bend 24. Each shaft section may be substantially cylindrical. Each shaft section may have a longitudinal axis. The bend(s) may set the longitudinal axes of the various shaft sections at certain angles (e.g. ± 30°, ± 45°) to each other. The bend(s) in the substantially hollow shaft 2 may allow the surgeon to work around soft tissue in the wound space, while using the surgical rotational tool driver 10. As shown in, for example, Figures 2A and 3 to 5, the surgical rotational tool driver 10 also includes a driveline 30. The driveline 30 is substantially hollow. The driveline 30 extends within the substantially hollow shaft 2. The driveline 30 allows torque to be transmitted through the surgical rotational tool driver 10 by rotating within the substantially hollow shaft 2. In particular, the driveline 30 has a proximal end that may be connected to a rotational power tool for applying torque through the driveline 30.

To accommodate the bend(s) in the substantially hollow shaft 2, the driveline 30 includes at least one universal joint. Each universal joint is located at a respective one of the bend(s). In the present embodiment, the driveline 30 includes a universal joint 80 located at the bend 22 and a universal joint 70 located at the bend 24. An example of the universal joints will be described in more detail below in relation to Figures 8 and 9.

Each universal joint may be located at the interface between two driveline sections of the driveline 30. For instance, in the present embodiment, the driveline 30 includes a distal driveline section 30 A, an intermediate driveline section 30B and a proximal driveline section 30C. The distal driveline section 30A extends distally from the universal joint 70 located at the bend 22. The intermediate driveline section 30B extends between the universal joint 70 located at the bend 22 and the universal joint 70 located at the bend 24. The proximal driveline section 30C extends proximally from the universal joint 70 located at the bend 24. The proximal end of the proximal driveline section 30C may be connected to a rotational power tool for applying torque through the driveline 30 as noted above. Each driveline section may be substantially cylindrical.

The various driveline sections of the driveline may be positioned for rotation within a respective one of the shaft sections of the substantially hollow shaft 2. Each driveline section may have a longitudinal axis. The longitudinal axes of the driveline sections may be coaxially aligned with the longitudinal axes of their respective shaft sections. For instance, in the present embodiment, the distal driveline section 30A rotates within the distal shaft section 12, the intermediate driveline section 30B rotates within the intermediate shaft section 14, and the proximal driveline section 30C rotates within the proximal shaft section 16.

As can be seen in Figures 1 to 7, the driveline 30 also includes a head part 40. The head part 40 of the driveline 30 extends distally from the distal end of the substantially hollow shaft 2. In the present embodiment, the head part 40 is located at a distal end of the distal driveline section 30A. The head part 40 may have a substantially cylindrical outer surface. As can be seen in, for instance, Figures 1 , 2A and 6, a diameter of the substantially cylindrical outer surface of the head part 40 may match a diameter of a substantially cylindrical outer surface of the distal shaft section 12, so that there is substantially no change in the outer diameter of the surgical rotational tool driver 10 at the interface between the distal end of the distal shaft section 12 and the head part 40.

The head part 40 is connectable to a surgical rotational tool. The surgical rotational tool may for instance be a reamer, such as an acetabular reamer 100 as shown in Figure 2B. As shown in Figure 2B, the acetabular reamer 100 may, for instance comprise a hemispherical dome 102 for insertion into the acetabulum of a patient. An outer surface of the dome 102 may include features 104 for grating bone away from the inner surface of the acetabulum as the acetabular reamer 100 rotates with the driveline 30.

To implement the connection between the head part 40 and the surgical rotational tool, the head part 40 may include distally located connection features 42 for connection with corresponding connection features of the surgical rotational tool. As shown in, for instance, Figures 6 and 7, the connection features 42 include a release mechanism for releasing the head part 40 from the surgical rotational tool.

In the present embodiment, the release mechanism includes one or more teeth 44 that are receivable within openings of the corresponding connection features of the surgical rotational tool. The teeth 44 extend distally from a slideably moveable central shaft 43 of the head part 40. The central shaft 43 may be substantially cylindrical. The central shaft 43 may be located in a centrally located bore in the head part 40.

The central shaft 43 may be biased distally with respect to the other features of the head part 40 using e.g. a spring 49. The spring 49 (which may, for instance be a helical spring as shown in Figure 2A) may be located in a space located between a distally facing surface of the head part 40 and a proximally facing surface of a flange of the central shaft 43 (see the region labelled 47 in Figure 6).

As will be described in more detail below, the central shaft 43 may be withdrawn proximally (e.g. along the longitudinal axis of the distal driveline section 30A - this is illustrated by the arrow labelled A in Figure 6) to withdraw the teeth 44 from the openings of the corresponding connection features. As shown in, for instance, Figures 2A, 5, 6, 8 and 10 to 12, the surgical rotational tool driver 10 also includes an actuation member 60. As noted above, the driveline 30 is substantially hollow. The actuation member 60 extends within the substantially hollow driveline 30 (see, e.g. Figures 2A, 5 and 6). The actuation member 60 is connected to the release mechanism. This can allow the release mechanism to be operated remotely. In particular, because the actuation member 60 extends within the substantially hollow driveline 30, the release mechanism may be operated at a position on the surgical rotational tool driver 10 that is located proximally with respect to the head part 40. In the present embodiment, the release mechanism is operated by withdrawing the actuation member 60 proximally within the driveline 30. A distal end 62 of the actuation member 60 is attached to the central shaft 43, as shown in Figures 2A and 6. To implement the attachment of the actuation member 60 to the central shaft 43, in the present embodiment the central shaft 43 includes a central axial bearing surface within which the actuation member 60 is rotationally received. The central axial bearing surface of the central shaft 43 includes an axial bore in the central shaft 43. The distal end of the actuation member 60 is received within and extends within the bore. The bore has a narrowed portion 46, which may be located at a proximal end of the bore. The actuation member 60 has a widened part 62, which is located distally with respect to the narrowed portion 46 of the bore.

In use, when the actuation member 60 is withdrawn proximally within the driveline 30 as noted above (see the arrows labelled A, B and C in Figures 2 A and 6), the widened part 62 of the actuation member 60 urges against the narrowed portion 46 whereby the central shaft 43 is moved proximally (e.g. against the bias provided by the spring 49), which in turns disengages the teeth 44 from the above described openings of the corresponding connection features of the surgical rotational tool. This allows the surgical rotational tool to be released from the head part 40 of the driveline 30.

The actuation member 60 may also by withdrawn proximally while the surgical rotational tool is being mounted on the head part 40. This may allow other connection features 42 of the head part 40 and the corresponding connection features of the surgical rotational tool to be manipulated into the correct position without interference from the teeth 44 of the central shaft 43. During rotation of the driveline 30 to transmit torque to the surgical rotational tool, it is envisaged that the driveline 30 may rotate relative to the actuation member 60. For instance, the actuation member 60 may remain substantially stationary during rotation of the driveline 30. In the present embodiment, the distal end of the actuation member 60 is rotationally received within the bore in the central shaft 43, to allow relative rotation between the actuation member 60 and the driveline 30. The inner bearing surface of the bore, and the surface of (at least the distal end of) the actuation member 60 may be smooth, so as to reduce friction between them as the driveline 30 rotates. It is anticipated that residual friction forces between the actuation member 60 and the inner bearing surface of the bore may cause some rotation of the actuation member 60 while the driveline 30 rotates, although it is anticipated that the angular velocity of the actuation member 60 would typically be substantially lower than that of the driveline 30. Similar considerations apply to the passage of the actuation member 60 through the substantially hollow central portion of the spider part(s) to be described below. Similar considerations also apply to attachment between the actuation member 60 to the inner sleeve 90 of the actuation mechanism to be described below, to allow relative rotation between the actuation member 60 to the inner sleeve 90 during rotation of the driveline 30.

The actuation member 60 may be substantially flexible. This may allow the actuation member 60 to navigate the bend(s) 22, 24 in the substantially hollow shaft 2. In some embodiments, the actuation member 60 may comprise a substantially flexible tension member. The actuation member 60 may, for instance, comprise a substantially flexible wire.

The actuation member 60 may comprise a polymer. In one example, the actuation member 60 may comprise Polytetrafluoroethylene (PTFE). In another example, the actuation member 60 may comprise polyethylene. For instance, an ultra-high molecular weight polyethylene could be used (e.g. Dyneema). In a further example, the actuation member 60 may comprise poly-para-phenylene terepthalamide (Kevlar). The actuation member 60 may, for instance, comprise an alloy. For instance, the alloy may be Nickel Titanium (Nitinol).

As noted above, the actuation member 60 extends within the substantially hollow driveline 30. As noted above, the flexible nature of the actuation member 60 can allow it to navigate the bend(s) 22, 24 in the substantially hollow shaft 2. The universal joint(s) 70 may, in accordance with an embodiment of this invention, be configured to allow the actuation member 60 to pass through it in such a way that it does not interfere with the operation of the universal joint(s) 70 during rotation of the driveline 30.

With reference to Figures 7 and 8, each universal joint 70 in this embodiment includes a pair of yokes, each yoke being located at an end of one of the two driveline sections that the universal joint 70 connects together. Each yoke includes a pair of arms 76. The arms 76 may be arranged at regular intervals around the universal joint (typically, as shown in the figures, the arms 76 of a first yoke are arranged at the 12 o’clock and 6 o’clock positions, while the arms 76 of a second yoke are arranged at the 3 o’clock and 9 o’clock positions.

In accordance with embodiments of this invention, the universal joint(s) 70 may include a substantially hollow central portion, through which the actuation member 60 extends. In the present embodiment, the substantially hollow central portion is comprised of a spider part 80 (see Figure 9).

The spider part 80 may include a body part 88. The body part 88 may be located at the center of the spider part 80. The spider part 80 may also include a number of legs 84. The legs may extend radially outward from the body part 88. The legs 84 may be circumferentially distributed around the body part 88. An end of each leg 84 is pivotally attached to one of the arms 76 of the yokes located at the ends of the driveline sections that the universal joint 70 interconnects. As shown in Figure 8, the ends of the legs 84 may pass through openings in the arms 76 to form pivotal connections 74. These pivotal connections allow the tilting of the driveline sections that the universal joint 70 interconnects, relative to each other, so as to allow the substantially hollow driveline 30 to navigate the bend(s) 22, 24 in the substantially hollow shaft 2.

In the present embodiment, the spider part 80 has four legs 84, which are circumferentially distributed around the body part 88 at the 12 o’clock, 3 o’clock, 6 o’clock and 9 o’clock positions, for pivotal attachment to a respective one of the arms 76. By way of example, the pivotal attachment of two of the legs 84 of a spider part 80 to the arms 76 of a yoke provided at the proximal end of the distal driveline section 30C is shown in Figure 8. The spider part 80 includes an aperture 82. The aperture 82 passes though the body part 88. The aperture 82 is may be centrally located within the body part 88. The actuation member 60 extends though the aperture 82. The intermediate driveline section 30B is omitted in Figure 8 to reveal the path of the actuation member 60 through the driveline and in particular through the aperture 82.

The provision of the aperture 82 in the body part 88 of the or each universal joint 70 of the driveline 30 can allow the actuation member 60 to extend within the substantially hollow driveline 30 while navigating the bend(s) 22, 24 in the substantially hollow shaft 2.

As mentioned above, it is envisaged that, during rotation of the driveline 30 to transmit torque to the surgical rotational tool, the driveline 30 may rotate relative to the actuation member 60. To allow this, the actuation member 60 is rotationally received within the aperture 82 in the body part 88. The inner surface of the aperture 82 and the surface of the actuation member 60 may be smooth, so as to reduce friction between them as the driveline 30 rotates. It is anticipated that residual friction forces between the actuation member 60 and the inner surface of the aperture 82 may cause some rotation of the actuation member 60 while the driveline 30 rotates, although it is anticipated that the angular velocity of the actuation member 60 would typically be substantially lower than that of the spider part 80.

In some embodiments, the surgical rotational tool driver 10 may include an actuation mechanism. The actuation mechanism may be located along the substantially hollow shaft 2. It is envisaged that the actuation mechanism may be located in a position that is remote from the distal end 6 of the substantially hollow shaft 2. In this position the actuation mechanism may be conveniently accessible by the surgeon. For instance, the actuation mechanism may be located outside the wound space even while the surgical rotational tool driver 10 is being used (i.e. while a surgical rotational tool attached to the head part 40 is located inside the wound space). In some embodiments, the actuation mechanism may be located proximally with respect to a mid-way point located equidistant the proximal end 4 and the distal end 6 of the substantially hollow shaft 2. In some embodiments, the actuation mechanism may be located at the proximal end of the substantially hollow shaft 2. In the present embodiment, the surgical rotational tool driver 10 includes an actuation mechanism that is located along the proximal shaft section 16 of the substantially hollow shaft 2. It is envisaged that the actuation mechanism may instead be located along the intermediate shaft section 14 of the substantially hollow shaft 2.

The actuation mechanism is operable to withdraw the actuation member 60 proximally within the driveline 30. As described above, the withdrawal of the actuation member 60 proximally within the driveline 30 operates the release mechanism for releasing the head part 40 from a surgical rotational tool.

The actuation mechanism of the present embodiment will be described below with reference to Figures 10 to 12.

The release mechanism in this embodiment includes an inner sleeve 90. The inner sleeve 90 may be substantially cylindrical. The inner sleeve 90 is mounted inside the proximal driveline section 30C of the driveline 30 (see Figure 11 - note that the driveline is not shown in Figures 10 or 12, so as to reveal the inner sleeve 90, its attachment to the actuation member 60 and the interaction between the inner sleeve 90 and the intermediate sleeve 100 to be described below). The inner sleeve 90 is configured to rotate with the driveline 30 (e.g. see the arrows labelled D in Figures 10 and 11).

In this embodiment, a proximal end of the actuation member 60 is attached to the inner sleeve 90. To implement the attachment of the actuation member 60 to the inner sleeve 90, the inner sleeve 90 is provided with a central opening that has an axial bearing surface within which the actuation member 60 is rotationally received. In this embodiment, the central opening comprises a bore. The bore has a narrowed portion 92, which may be located at a proximal end of the bore. The actuation member 60 has a widened part 64, which is located proximally with respect to the narrowed portion 92 of the bore. By operating the actuation mechanism to move the inner sleeve 90 proximally, the actuation member 60 may be withdrawn in a proximal direction (see the arrow labelled C in Figure 11) within the driveline 30 as described above.

In this embodiment, the driveline 30 has one or more openings 32 located in a side wall thereof. The openings 32 are slot shaped, with their long dimension substantially parallel to the longitudinal axis of the proximal driveline section 30C. The inner sleeve 90 has one or more first members 94. The first members 94 may be substantially cylindrical, and may extend radially outward from an outer surface of the inner sleeve 90. The first members 94 each extend through a respective one of the opening(s) 32 located in the side wall of the driveline 30 (see also Figure 4). Note that when the driveline 30 rotates, the inner sleeve 90 rotates with the driveline 30, owing to the engagement of the first member(s) 94 with their respective openings 32.

Each first member 94 is slideable back and forth within its respective opening 32 located in the side wall of the driveline 30, along the long dimension of the opening 32. This can allow the inner sleeve 90 as a whole to move back and forth along the longitudinal axis of the proximal driveline section 30C. When the inner sleeve 90 is moved proximally as noted above, an edge of the bore, formed by proximal end of the narrowed portion 92, urges against the widened part 64 of the actuation member 60, thereby to withdraw the actuation member 60 proximally within the driveline 30.

As described above, it is envisaged that, during rotation of the driveline 30 to transmit torque to the surgical rotational tool, the driveline 30 (and hence the inner sleeve 90) may rotate relative to the actuation member 60. For instance, the actuation member 60 may remain substantially stationary during rotation of the driveline 30 and the inner sleeve 90. To allow this, the actuation member 60 may be rotationally received within the bore in the inner sleeve 90. The inner surface of the bore in the inner sleeve 90 and the surface of the actuation member 60 may be smooth, so as to reduce friction between them as the driveline 30 and the inner sleeve 90 rotate. It is anticipated that residual friction forces between the actuation member 60 and the inner surface of the bore in the inner sleeve 90 may cause some rotation of the actuation member 60 while the driveline 30 and the inner sleeve 90 rotate, although it is anticipated that the angular velocity of the actuation member 60 would typically be substantially lower than that of the driveline 30 and the inner sleeve 90. In this embodiment, the actuation mechanism also comprises an intermediate sleeve

100. The intermediate sleeve 100 is mounted between an outer surface of the drive line 30 and an inner surface of the substantially hollow shaft 2. The intermediate sleeve 100 may be substantially cylindrical. In this embodiment, the proximal shaft section 16 has one or more openings 112 located in a side wall thereof. The openings 112 are slot shaped, with their long dimension substantially parallel to the longitudinal axis of the proximal shaft section 16. The intermediate sleeve 100 has one or more second members 104. The second members 104 may be substantially cylindrical, and may extend radially outward from an outer surface of the intermediate sleeve 100. The second members 104 each extend through a respective one of the opening(s) 112 located in the side wall of the proximal shaft section 16.

Each second member 104 is slideable back and forth within its respective opening 112 located in the side wall of the proximal shaft section 16, along the long dimension of the opening 112. This can allow the intermediate sleeve 100 as a whole to move back and forth along the longitudinal axis of the proximal shaft section 16 (which may be parallel to the longitudinal axis of the proximal driveline section 30C). The intermediate sleeve 100 includes a central opening having an axial bearing surface within which the (proximal driveline section 30C of the) driveline 30 is rotationally received to allow rotation of the driveline 30 while the intermediate sleeve remains substantially stationary. Note that when the driveline 30 rotates, the intermediate sleeve 100 cannot rotate with the driveline 30, owing to the engagement of the second member(s) 104 with their respective openings 112.

In this embodiment, a part of the central opening of the intermediate sleeve 100 has an increased diameter to form an inwardly facing circumferential slot 106. As can be seen in the Figures, the slot 106 may be substantially annular in shape. An outer end of the or each first member 94 of the inner sleeve 90 extending through the opening(s) 32 located in the side wall of the proximal driveline section 30C is rotationally received within the annular slot 106. This allows the inner sleeve 90 to rotate with the driveline 30 as described above, while the outer end of the or each first member 94 rides within the slot 106. On the other hand, when the intermediate sleeve 100 as a whole is moved back and forth along the longitudinal axis of the proximal shaft section 16 as noted above, the edges of the slot 106 urge against the or each first member 94, which in turn moves the or each first member 94 within its respective opening 32, whereby the inner sleeve 90 moves axially with along the intermediate sleeve 100. Accordingly, by moving the intermediate sleeve 100 in a proximal direction, the inner sleeve 90 can also be moved proximally, in turn to proximally withdraw the actuation member 60 within the driveline 30 to operate the release mechanism.

As shown in Figure 12, the intermediate sleeve 100 may include one or more apertures 108. The aperture(s) 108 may extend radially through the sidewall of the intermediate sleeve 100 and in this embodiment the aperture(s) 108 open out into the slot 106. The aperture(s) 108 may allow the first members 94 to pass through them for assembly with the inner sleeve 90 during manufacture of the surgical rotational tool driver 10. The inner sleeve 90 may include one or more radially extending bores located in an outer curved (cylindrical) surface thereof, into which the first members 94 may be inserted.

In this embodiment, the actuation mechanism further comprises an outer sleeve 50. The outer sleeve 50 is slideably mounted on an outer surface of the (proximal shaft section 16 of the) substantially hollow shaft 2. The outer sleeve 50 may be substantially cylindrical. Proximal and/or distal ends of the outer sleeve 50 may be tapered in towards longitudinal axis of the proximal shaft section 16, to provide the surgical rotational tool driver 10 with a smooth profile.

In this embodiment, the outer sleeve 50 is connected to the or each second member 104. In particular, the outer ends of each of the second member(s) 104 may extend radially outward through the opening(s) 112, to be received in a respective opening 52 located in the outer sleeve 50 (e.g. see Figure 10). The openings 52 of the outer sleeve 50 within which the second member(s) 104 are received may be shaped to conform with the outer surfaces of the second member(s) 104, so as to form a press fit between the openings 52 and the second member(s) 104.

The connection of the outer sleeve 50 to the second member(s) 104 allows the outer sleeve 50 to be moved back and forth along the longitudinal axis of the proximal shaft section 16 thereby the move intermediate sleeve 100 axially. As described above, this in turn moves the inner sleeve 90 axially, so that the actuation member 60 can be withdrawn proximally to operate the release mechanism.

The outer sleeve 50 thus provides the surgeon with a means by which to manually operate the actuation mechanism, which in turn operates the release mechanism as described above. It is envisaged that in embodiments in which the central shaft 43 is biased distally (e.g., by the spring 49), when the surgeon releases outer sleeve 50, each of the inner sleeve 90, the intermediate sleeve 100 and the outer sleeve 50 may return to a locking position of the actuation mechanism under the tension in the actuation member 60. This locking position may thus be a default position of the actuation mechanism. A release position of the actuation mechanism may be reached by manually moving the outer sleeve 50 (and thus the inner sleeve 90 and the intermediate sleeve 100) proximally.

A surgical rotational tool driver according to an embodiment of this invention may be included in a surgical kit. The kit may also include one or more differently sized acetabular reamers 100 connectable to the head part of the driveline of the surgical rotational tool driver.

A method of operating a surgical rotational tool driver 10 of the kind described above may include connecting the one or more connection features 42 of the head part 40 of the substantially hollow driveline 30 to a surgical rotational tool. As noted previously, this may involve withdrawing the actuation member 60 proximally (e.g. by operating the release mechanism), to allow connection features 42 of the head part 40 and the corresponding connection features of the surgical rotational tool to be manipulated into the correct position without interference from the teeth 44 of the central shaft 43.

The surgical rotational tool may, for example, be an acetabular reamer driver of the kind shown in Figure 2B.

Having attached the surgical rotational tool to the surgical rotational tool driver 10, the method may then include applying torque through the driveline 30. This may involve connecting a rotational power tool to the proximal end of the driveline 30 as noted above, and then operating the rotational power tool.

The method may also include operating the release mechanism described above to release the head part 40 from the surgical rotational tool by withdrawing the actuation member 60 proximally within the driveline 30.

Accordingly, there has been described a surgical rotational tool driver and a method of operating the same. The driver includes a hollow shaft having a proximal end, a distal end and at least one bend. The driver includes a hollow driveline extending within the shaft. The driveline has a universal joint located at each bend. The driveline has a proximal end connectable to a rotational power tool for applying torque. The driveline has a head part extending distally from the distal end of the shaft. The head part includes connection features for connecting to a surgical rotational tool. The connection features include a release mechanism for releasing the head part from the surgical rotational tool. The driver includes an actuation member extending within the substantially hollow driveline. The actuation member is connected to the release mechanism for operating the release mechanism at a position located proximally with respect to the head part.

Although particular embodiments of the invention have been described, it will be appreciated that many modifications/additions and/or substitutions may be made within the scope of the claimed invention.

Claims

1 A surgical rotational tool driver comprising:

a universal joint located at each said bend in the shaft;

2. The surgical rotational tool driver of claim 1, wherein the or each universal joint includes a substantially hollow central portion through which the actuation member extends.

3. The surgical rotational tool driver of claim 2, wherein the or each universal joint connects an end of a driveline section of the driveline to an end of another driveline section of the driveline and comprises:

a spider part pivotally attached to said end of each driveline section; and an aperture in the spider part,

wherein the actuation member extends though the aperture.

4. The surgical rotational tool driver of any preceding claim comprising an actuation mechanism located along the shaft for withdrawing the actuation member proximally within the driveline.

The surgical rotational tool driver of claim 4, wherein the actuation mechanism comprises:

one or more openings located in a side wall of the substantially hollow driveline; and

an inner sleeve mounted inside the driveline for rotation with the driveline, the inner sleeve having one or more first members extending through respective ones of said opening(s) in the side wall of the driveline;

wherein the inner sleeve includes a central opening having an axial bearing surface within which the actuation member is rotationally received to allow rotation of the inner sleeve with the driveline and relative to the actuation member;

wherein the actuation member has a part having a radial dimension that is larger than a radial dimension of the central opening of the inner sleeve; and

wherein the or each first member is axially slideable within the respective opening(s) located in the side wall of the driveline to allow an edge of the central opening to urge against the part of the actuation member having a larger radial dimension to withdraw the actuation member proximally within the driveline.

The surgical rotational tool driver of claim 5, wherein the actuation mechanism comprises:

one or more openings located in a side wall of the substantially hollow shaft; and

an intermediate sleeve mounted between an outer surface of the drive line and an inner surface of the shaft, the intermediate sleeve having one or more second members extending through respective ones of said opening(s) in the side wall of the shaft;

wherein the intermediate sleeve includes a central opening having an axial bearing surface within which the driveline is rotationally received to allow rotation of the driveline while the intermediate sleeve remains substantially stationary;

wherein a part of the central opening has an increased diameter to form a slot within which the end of the or each first member of the inner sleeve extending through the opening(s) located in the side wall of the driveline is rotationally received; and wherein the or each second member is axially slideable within the respective opening(s) located in the side wall of the shaft to allow an edge of the slot to urge against the end of the or each first member to slide the inner sleeve axially to withdraw the actuation member proximally within the driveline.

7. The surgical rotational tool driver of claim 6, wherein the actuation mechanism comprises an outer sleeve slideably mounted on an outer surface of the shaft, wherein the outer sleeve is connected to the or each said second member for moving the intermediate member proximally to withdraw the actuation member proximally within the driveline.

8. The surgical rotational tool driver of any of claims 4 to 7, wherein the actuation mechanism is located closer to the proximal end of the shaft than to the distal end of the shaft.

9. The surgical rotational tool driver of any of claims 4 to 8, wherein the shaft includes at least two bends located intermediate the distal end of the shaft and the actuation mechanism.

10. The surgical rotational tool driver of any preceding claim, wherein the release mechanism comprises one or more teeth receivable within openings of the corresponding connection features, wherein the teeth extend distally from a slideably moveable central shaft of the head part, and wherein the actuation member is attached to the central shaft for withdrawing the teeth from the openings of the corresponding connection features by withdrawing the central shaft proximally by withdrawing the actuation member proximally.

11. The surgical rotational tool driver of claim 10, wherein the central shaft is biased distally.

12. The surgical rotational tool driver of claim 10 or claim 11, wherein the central shaft includes a central axial bearing surface within which the actuation member is rotationally received to allow rotation of the head part relative to the actuation member.

13. The surgical rotational tool driver of any preceding claim, wherein the actuation member comprises a substantially flexible tension member.

14. The surgical rotational tool driver of claim 13, wherein the substantially flexible tension member comprises a wire.

15. The surgical rotational tool driver of any preceding claim, wherein the actuation member comprises a polymer or an alloy.

16. The surgical rotational tool driver of any preceding claim, wherein the surgical rotational tool driver is a reamer driver.

17. The surgical rotational tool driver of claim 16, wherein the surgical rotational tool is an acetabular reamer.

18. A surgical kit comprising a surgical rotational tool driver according to any preceding claim and a surgical rotational tool having said corresponding connection features.

19. A method of operating a surgical rotational tool driver, the method comprising:

said driveline, wherein the driveline is substantially hollow and extends within the hollow shaft, the driveline having:

a universal joint located at each said bend in the shaft;

said head part, wherein the head part extends distally from the distal end of the shaft, said connection features including a release mechanism for releasing the head part from the surgical rotational tool; and an actuation member extending within the substantially hollow driveline, wherein the actuation member is connected to the release mechanism; and

20. The method of claim 19, wherein the or each universal joint includes a substantially hollow central portion through which the actuation member extends.

21. The method of claim 20, wherein the or each universal joint connects an end of a driveline section of the driveline to an end of another driveline section of the driveline and comprises:

wherein the actuation member extends though the aperture.

22. The method of any of claims 19 to 21, comprising:

connecting the proximal end of the driveline to a rotational power tool; and prior to operating the release mechanism, applying torque through the driveline.

23. The method of claim 22, wherein the substantially hollow driveline rotates relative to the actuation member while torque is applied through the driveline.

24. The method of any of claims 19 to 23, comprising using an actuation mechanism located along the shaft for withdrawing the actuation member proximally within the driveline.

25. The method of claim 24, wherein the shaft includes at least two bends located intermediate the distal end of the shaft and the actuation mechanism.

26. The method of any of claims 19 to 25, wherein the actuation member comprises a substantially flexible tension member.

27. The method of any of claims 19 to 26, wherein the surgical rotational tool driver is a reamer driver.