Acetabular reaming drill handle and method for reaming acetabulum

Abstract

The present invention discloses an acetabular reamer handle, which includes a shaft having a distal end, a neck component having a longitudinal axis, a transmission system extending through the shaft and the neck component, and a locking mechanism. The distal head component of the transmission system is mounted for rotation around the longitudinal axis of the neck component and can be connected to the reamer. The distal end of the shaft and the proximal end of the neck component are pivotally attached to allow the shaft to be tilted relative to the longitudinal axis. The tilt allows observation of the acetabulum and / or the reamer portion that was originally shielded. The locking mechanism includes an engagement member having an engagement surface located at the distal end of the shaft. The engagement member can be moved distally to push the engagement surface onto the proximal end of the neck component.

Description

Technical Field

[0001] The present invention relates to an acetabular reaming drill handle and a method for reaming an acetabulum in hip replacement surgery. Background Art

[0002] Hip replacement is a surgical procedure in which the hip joint is replaced by a prosthetic implant. As part of a hip replacement procedure, the patient's acetabulum can be prepared to accommodate an acetabular cup implant by reaming the acetabulum to an appropriate size and depth. The present invention discloses a surgical tool for reaming the acetabulum, which may include a reamer having a substantially hemispherical dome to be accommodated in the acetabulum. The reamer may also include a feature structure located on the outer surface of the dome, which is used to smooth the inner surface of the acetabulum when the reamer rotates. The reamer may be attached to the distal end of a tubular reamer handle to allow a surgeon to manipulate the reamer (e.g., to position the dome in the acetabulum and apply a force for pressing the reamer against the inner surface of the acetabulum when the reamer rotates). A drive train may extend within the reamer handle for transmitting torque to the reamer.

[0003] A variety of reamer shanks may be used.

[0004] One type of reamer shank is an offset reamer shank. Such a reamer shank may include a pair of bends in the tube, thereby forming a dog-leg configuration, which may allow a surgeon to more easily work around soft tissue.

[0005] Another reamer shank may include a single bend.

[0006] Still another reamer shank may be substantially straight (ie, not including a bend).

[0007] WO2003 / 065906 describes a surgical device for holding and rotating an acetabular reaming head. The device comprises a shaft having a length extending from a first end to a second end, the first end being adapted to hold an acetabular reaming head. At least a portion of the shaft diverges from an axis defined by the first and second ends of the shaft, for example, the shaft may comprise a C-shaped divergent portion. Thus, the head held by the device may enter the acetabulum in its true anatomical position while avoiding the shaft from intruding into surrounding body parts.

[0008] During hip replacement surgery, visibility is often quite limited. For example, when using a reamer handle, it may be difficult for the surgeon to inspect the dome of the reamer when the reamer is in the acetabulum (e.g., for assessing reaming depth). In situ, the dome may be at least partially obscured, for example, by soft tissue and / or the reamer handle. To assess reaming depth, the surgeon may remove the reamer handle and reamer from the incision site, or alternatively may remove the reamer handle from the reamer so as to observe the acetabulum and reamer while the reamer is still in situ, but in either case this is inconvenient.

[0009] US 8,052,690 describes an orthopedic reamer driver comprising a tubular housing having at least one first positioning feature structure. A drive shaft within the housing has a drive end. A variable angle cap is pivotally coupled to the housing adjacent the drive end. The variable angle cap comprises at least one leg extending along a side of the housing. Each leg has a second positioning feature structure that selectively engages and disengages with a corresponding first positioning feature structure at a selected angular position among a plurality of angular positions. Each second positioning feature structure holds the variable angle cap at the selected angular position when engaged with the corresponding first positioning feature structure. A variable angle joint is coupled to the drive end, and a reamer drive head is coupled to the variable angle joint.

[0010] US 7,008,430 describes a positioning tool for a glenoid cutting instrument or implant, which is designed to be used with minimally invasive surgery and used in combination with computer-assisted surgery. The positioning tool has a longitudinally extending drive shaft, which has a movable joint at a first end and a drive coupling for connecting to a power source at a second end. A retainer for mounting a cutting tool such as a drill or as an acetabular cutting instrument or for mounting an acetabular implant is connected to a movable joint at the first end of the drive shaft for movement relative to the drive shaft. When the drive shaft rotates, the retainer can rotate around its central axis. The drive shaft includes a bearing mounted thereon, which is pivotally connected to the shaft at a fixed longitudinal position and pivotally connected to a longitudinally extending first arm having a handle. A tracking system that can be utilized by a computer-assisted surgical system is mounted on the first arm. A second arm is provided, which is pivotally connected to the retainer at the first end and pivotally connected to the first arm at the second end. The resulting four-bar linkage allows manipulation of the holder and cutting instrument / implant in any position, while the known geometric relationship between the tracker and the holder allows the computer to display the position of the holder relative to the joint on the cathode ray tube.

[0011] US 2005 / 159751A1 describes an orthopedic reamer driver comprising a tubular housing having at least one first positioning feature structure. A drive shaft within the housing has a drive end. A variable angle cap is pivotally connected to the housing adjacent to the drive end. The variable angle cap comprises at least one leg extending along the side of the housing. Each leg has a second positioning feature structure that selectively engages and disengages with a corresponding first positioning feature structure at a selected angular position among a plurality of angular positions. Each second positioning feature structure holds the variable angle cap at the selected angular position when engaged with the corresponding first positioning feature structure. A variable angle joint is connected to the drive end, and a reamer drive head is connected to the variable angle joint.

[0012] WO 2018 / 033788 A1 describes a surgical reamer driver device that provides a fully closed tube that prevents the intrusion of debris and minimizes the wear of soft tissue during use. The reamer device includes a minimum number of component assemblies to allow easy replacement and minimize wear. The surgical reamer driver has: a housing assembly in a separate assembly unit; a transmission drive system enclosed in the housing assembly in a separate assembly unit, and the transmission drive system has at least one double universal joint and a surgical tool connector at its distal end; a motor shaft coupling in a separate assembly unit at its proximal end; and a handle assembly in a separate assembly unit at its proximal end, these four basic components form a driver that effectively prevents debris from entering the internal working area of ​​the driver in a fully assembled state. A method for disassembling a reamer driver comprises the following steps: a. actuating a sliding release sleeve to unlock the handle assembly from the housing assembly, thereby allowing the drive train to be unsealed within the housing assembly; b. sliding the handle assembly away from the housing, thereby effectively unsealing the drive train; c. pulling the motor shaft coupling out of the housing, thereby freeing the drive train from axial restraint at one end; d. loosening the drive train at the one end and lifting the one end away from the housing assembly, thereby allowing the drive train to be removed; and e. pulling the drive train out of the housing assembly, thereby removing the drive train from the housing assembly.

[0013] US 2004 / 097947 A1 describes an orthopedic reamer assembly for minimizing surgical trauma, the orthopedic reamer assembly comprising a reamer and a driver. The driver comprises a shaft having a distal end and a longitudinal axis; and a driver head connected to the distal end. The driver head is capable of pivoting about an axis substantially perpendicular to the longitudinal axis. The reamer is connected to the driver head.

[0014] EP 2 954 860 A2 describes an orthopedic reamer handle, comprising: a reamer portion, which is configured to transmit torque to a reamer head; a driver portion, which is connected to the reamer portion and is configured to receive and transmit torque from the driver; and a drive train, which connects the reamer portion and the driver portion and is configured to transmit torque from the driver portion to the reamer portion, the drive train comprising: a first drive shaft, which has a first end and a second end, the first end is connected to the driver portion, and the first drive shaft defines a first axis; a first intermediate connector, which has a first intermediate end and a second intermediate end, the first intermediate end is connected to the second end; a biasing member, which has a third end and a fourth end, the third end is connected to the second intermediate end at an acute angle relative to the first axis, and the biasing member defines a second axis; and a second intermediate connector, which connects the fourth end to the reamer portion at an acute angle relative to the second axis. Summary of the invention

[0015] Aspects of the invention are presented in conjunction with the independent and dependent claims. Combinations of features from the dependent claims may be combined with features of the independent claims as appropriate and not just as explicitly presented in the claims.

[0016] According to one aspect of the present invention, there is provided a reamer shank, the reamer shank comprising:

[0017] a hollow shaft having a distal end;

[0018] a hollow neck member having a longitudinal axis;

[0019] a drive train extending through the shaft and the neck component, wherein a distally located head component of the drive train is mounted for rotation about the longitudinal axis of the neck component and is connectable to an acetabular reamer, and wherein the distal end of the shaft and the proximal end of the neck component are pivotally attached to allow the shaft to tilt relative to the longitudinal axis of the neck component; and

[0020] A locking mechanism comprising an engagement member having an engagement surface at the distal end of the shaft, wherein the engagement surface is substantially circumferential relative to the longitudinal axis of the hollow shaft at the distal end of the shaft, and wherein the engagement member is movable distally to push the engagement surface against the proximal end of the neck component to resist the tilting of the shaft relative to the longitudinal axis of the neck component.

[0021] The inclination of the shaft relative to the longitudinal axis of the neck component can allow for viewing of a portion of the acetabulum and / or reamer that would otherwise be obscured by the reamer handle. This can, for example, allow a surgeon to better view to determine the depth of reaming of the acetabulum without having to remove the reamer and reamer handle from the acetabulum or detach the reamer handle from the reamer. The locking mechanism can be used to prevent undesired tilting of the shaft when the reamer is operated. The locking mechanism can be simple to operate and can have a compact, robust configuration that does not need to include complex parts that would otherwise increase the cost of the reamer handle and / or reduce the reliability of the reamer handle.

[0022] The proximal end of the neck component may comprise a surface for engaging with the engagement surface of the engagement member.The surface of the proximal end of the neck component may be contained in a plane.

[0023] The surface of the proximal end of the neck component may have a surface normal that is oriented at a non-angle α relative to the longitudinal axis of the neck component. Typically, α may be less than 90° to allow for correct operation of the drive train. The angling of the neck component relative to the axis may allow a surgeon to more easily work around soft tissue in an incision site. In some embodiments, 30°≤α≤60°. In some embodiments, α is about 30°. In some embodiments, α is about 45°.

[0024] The surface of the proximal end of the neck component may be contained in a plane having a surface normal oriented parallel to the longitudinal axis of the neck component. In some embodiments, this may allow the acetabular reamer handle to operate as a straight reamer handle (although the reamer handle can be tilted as described above).

[0025] The engagement member may be slidably mounted inside the hollow shaft. The engagement member may be configured to protrude from the distal end of the hollow shaft to push the engagement surface against the proximal end of the neck component. In this way, components of the locking mechanism may be protected by the wall of the shaft, in which case fluid and / or bone fragments in the incision site will not interfere with the operation of the components.

[0026] The engagement member may be resiliently biased distally to push the engagement surface onto the proximal end of the neck component. To achieve this, the locking mechanism may include a coil spring mounted coaxially relative to the distal end of the hollow shaft and proximally relative to the engagement member. The coil spring may be mounted inside the hollow shaft. Again, this may protect the spring from being obstructed by fluid and / or bone fragments in the incision site.

[0027] The engagement member may include a handle component for manually retracting the engagement member in a proximal direction to release the engagement surface from the proximal end of the neck component. This may allow a surgeon to selectively release the shaft to allow the shaft to tilt while keeping the shaft locked during operation of the reamer.

[0028] The acetabular reamer may include one or more locking members extending from the engagement surface to be accommodated in one or more corresponding openings in the proximal end of the neck component. The arrangement may allow the engagement surface to lock on the proximal end of the neck component to resist the tilt of the shaft relative to the longitudinal axis of the neck component. Where more than one such locking member is provided, the locking members may be distributed (e.g., evenly distributed) around the periphery formed by the engagement surface of the engagement member. For example, the acetabular reamer may include two locking members, one of which is located on either side of the plane of the longitudinal axis containing the hollow shaft and the hollow neck component.

[0029] The drive train may include a universal joint at the pivot point between the distal end of the shaft and the proximal end of the neck component. This may allow the angle between the handle component (in which the head component can rotate) and the shaft to be accommodated.

[0030] The acetabular reamer shank may be an offset acetabular reamer shank, wherein the hollow shaft includes a proximal shaft section and a distal shaft section, and wherein the shaft has a bend at an interface between the proximal shaft section and the distal shaft section. The proximal shaft section and the distal shaft section may be rigidly formed, whereby an angle between the longitudinal axis of the distal shaft section and the longitudinal axis of the proximal shaft section may be fixed.

[0031] The engagement surface may be substantially annular, triangular, rectangular, pentagonal or hexagonal.

[0032] According to another aspect of the present invention, a surgical kit is provided, the surgical kit comprising the acetabular reamer handle of the type described above and one or more acetabular reamer of different sizes connectable to the head component of the acetabular reamer handle.

[0033] According to yet another aspect of the present invention, there is provided a method of reaming a patient's acetabulum using a reamer connected to a reamer handle, the reamer handle comprising:

[0034] a hollow shaft having a distal end;

[0035] a hollow neck member having a longitudinal axis;

[0036] a drive train extending through the shaft and the neck component, wherein a distally located head component of the drive train is mounted for rotation about the longitudinal axis of the neck component and connected to the reamer, and wherein the distal end of the shaft and the proximal end of the neck component are pivotally attached to allow the shaft to be tilted relative to the longitudinal axis of the neck component;

[0037] The method comprises:

[0038] inserting the reamer into the acetabulum;

[0039] operating the reamer to remove bone from a surface of the acetabulum; and

[0040] With the reamer positioned in the acetabulum, the shaft is tilted relative to the longitudinal axis of the neck component to view the acetabulum and / or a portion of the reamer that would otherwise be obscured by the reamer handle.

[0041] The inclination of the shaft relative to the longitudinal axis of the neck component allows viewing of a portion of the acetabulum and / or reamer that would otherwise be obscured by the reamer shank without removing the reamer and reamer shank from the acetabulum or detaching the reamer shank from the reamer.

[0042] The method may also include tilting the reamer handle about the longitudinal axis of the neck component to view the acetabulum and / or a portion of the reamer that is otherwise obscured by the reamer handle.

[0043] The method may further include viewing the acetabulum and / or the portion of the reamer that was originally obscured by the reamer handle to determine the depth of the reaming.

[0044] The method may further include operating a locking mechanism of the reamer shank to disengage an engagement member of the locking mechanism from the proximal end of the head component to allow tilting of the shaft relative to the longitudinal axis of the neck component.

[0045] The engagement member may be movable distally to urge the engagement surface against the proximal end of the neck component to resist the tilting of the shaft relative to the longitudinal axis of the neck component.

[0046] The engagement member may be resiliently biased towards the proximal end of the head piece. This may be achieved using a helical spring as described above.

[0047] The engagement member may be slidably mounted on or in the shaft.The method may further comprise manually retracting the engagement member in a proximal direction to release the engagement member from the proximal end of the neck component.

[0048] The engagement member may have an engagement surface at the distal end of the shaft for engaging with the proximal end of the neck component to resist the tilting of the shaft relative to the longitudinal axis of the neck component. The engagement surface is substantially circumferential relative to the longitudinal axis of the hollow shaft at the distal end of the shaft.

[0049] The engagement surface may be substantially annular, triangular, rectangular, pentagonal or hexagonal.

[0050] The reamer shank may be an offset reamer shank, wherein the hollow shaft includes a proximal shaft section and a distal shaft section, and wherein the shaft has a bend at an interface between the proximal shaft section and the distal shaft section. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Embodiments of the invention will hereinafter be described, by way of example only, with reference to the accompanying drawings, in which like reference numerals associate with like elements, and in which:

[0052] Figure 1A A side view of an acetabular reamer handle according to an embodiment of the present invention is shown;

[0053] Figure 1B 1 shows a side view of the acetabular reamer handle of FIG. 1 , wherein the acetabular reamer is connected to a distal head component of a drive train of the acetabular reamer handle;

[0054] Figure 2 Shows Figure 1A A cross section of the acetabular reamer handle;

[0055] Figure 3Shows the direction Figure 1A a close up view of the components positioned with the distal end of the shaft of the acetabular reamer handle;

[0056] Figure 4 Shows the direction Figure 1A a close-up cross-section of the component with the distal end of the shaft of the acetabular reamer handle positioned;

[0057] Figure 5 Shows Figure 1A Another side view of the acetabular reamer handle;

[0058] Figure 6 Shows Figure 1A Another cross-section of the acetabular reamer handle;

[0059] Figure 7 Shows Figure 1A An exploded view of the acetabular reamer handle;

[0060] Figure 8 A close-up view showing components positioned toward the distal end of the shaft of an acetabular reamer handle according to another embodiment of the present invention; and

[0061] Fig. 9 Shows the direction Figure 8 Another close up view of the components positioned at the distal end of the shaft of the acetabular reamer handle. DETAILED DESCRIPTION

[0062] Embodiments of the present invention are described below with reference to the accompanying drawings.

[0063] Figure 1 to Figure 7 Various views of an acetabular reamer handle 10 are shown in accordance with an embodiment of the present invention.

[0064] The acetabular reamer handle 10 includes a shaft 20. The shaft 20 has a proximal end 34 and a distal end 32. The shaft 20 is substantially hollow (see, e.g., Figure 2 cross section).

[0065] In this embodiment, the shaft 20 includes a distal shaft section 20A and a proximal shaft section 20B. The shaft sections 20A, 20B are fixedly joined together at a bend 28 in the shaft 20, whereby the longitudinal axis 26 of the distal shaft section 20A is oriented at an angle β to the longitudinal axis 66 of the proximal shaft section 20B (see, e.g., Figure 1A). Each shaft segment 20A, 20B may have a distal end and a proximal end. In the present embodiment, the proximal end of the distal shaft segment 20A is joined to the distal end of the proximal shaft segment 20B at the aforementioned bend 28. The angle β may be in the range of 30°≤β≤60°. Specifically, it is conceivable that in some embodiments, β=30° or β=45°.

[0066] It is also contemplated that the shaft 20 may be substantially straight, without the bend shown in the figures of this embodiment.

[0067] The shaft 20 (including, for example, its constituent shaft sections 20A, 20B) may be generally elongated, cylindrical in shape, and may have a substantially circular cross-section.

[0068] One or more handle components 60 can be disposed on the shaft 20 to facilitate holding the acetabular reamer handle 10 and to allow the surgeon to apply an axial force for pushing the reamer attached to the distal end of the acetabular reamer handle 10 into the inner surface of the patient's acetabulum during reaming. As shown, each handle component 60 can extend radially outward from the side of one of the shafts 20. The handle component 60 can be positioned toward the proximal end of the shaft 20. In the present embodiment, the acetabular reamer handle 10 includes a single handle component 60 that extends radially outward from the side of the attached shaft segment 20B.

[0069] The acetabular reamer handle 10 also includes a neck component 6. The neck component 6 is substantially hollow. The neck component 6 can be substantially cylindrical and can have a substantially circular cross-section. The neck component 6 has a proximal end 62, a distal end 64, and a longitudinal axis 46. As will be described in more detail below, the proximal end 62 of the neck component 6 is pivotally connected to the distal end 32 of the shaft 20 to allow the shaft 20 to tilt relative to the longitudinal axis 46 of the neck component 6.

[0070] The acetabular reamer handle 10 also includes a transmission system 40. The transmission system 40 is Figure 7 , and the components of the drive train 40 are also shown in the exploded view of Figure 1A , Figure 1B , Figure 3 , Figure 5 , Figure 8 and Fig. 9 For clarity, Figure 2 , 4 Only the head member 42 of the drive train 40 (described below) is shown in cross section in Figures 1 and 6. The drive train 40 is elongated and sized to fit within and extend through the hollow shaft 20 and neck member 6.

[0071] The drive train 40 may include a plurality of drive train sections. Generally speaking, in embodiments where the shaft 20 includes one or more bends such as the bend 28, the drive train 40 may include a corresponding drive train section for each shaft section of the hollow shaft 20. In the present embodiment, these drive train sections include a distal drive train section 40A and a proximal drive train section 40B. In order to accommodate any bends in the shaft 20 (as well as the angle between the shaft 20 and the neck component 6, which will be described below), the drive train 40 may include one or more universal joints positioned along its length. In the present embodiment, the drive train 40 includes a first universal joint 48A and a second universal joint 48B, the first universal joint coupling the proximal end of the head component 42 of the drive train 40 to the distal end of the distal drive train section 40A, and the second universal joint connecting the proximal end of the distal drive train section 40A to the distal end of the additional drive train section 40B.

[0072] The proximal end 34 of the shaft 20 of the acetabular reamer handle 10 (which in this embodiment is formed by an additional shaft section 20B having two shaft sections) can have an opening through which the proximal end 45 of the drive train 40 can pass and protrude. The proximal end 45 of the drive train 40 may include a connection feature structure for connecting to a power tool (such as a rotary drive for applying torque to the drive train 40). In use, the drive train 40 rotates to transmit torque to the distal head component 42 of the drive train 40 through the hollow shaft 20 and the neck component 6. The head component 42 of the drive train 40 can be connected to the reamer 100. Figure 1B A side view of the acetabular reamer handle 10 of FIG. 1 is shown, wherein the acetabular reamer 100 is connected to the head component 42 of the drive train 40. To achieve the connection between the head component 42 and the acetabular reamer 100, the head component 42 may include a distally located connection feature structure 44 for connecting with a corresponding connection feature structure of the acetabular reamer 100. Figure 1B As shown, the acetabular reamer 100 may include, for example, a hemispherical dome 102 for insertion into the acetabulum of a patient. The outer surface of the dome 102 may include features 104 for grinding bone away from the inner surface of the acetabulum when the acetabular reamer 100 rotates with the drive train 40.

[0073] The head component 42 is mounted for rotation about the longitudinal axis 46 of the neck component 6. The rotation axis of the head component 42 can be substantially coaxial with the longitudinal axis 46. In this example, the proximal end of the head component 42 is located inside the neck component 6. The outer surface of the head component 42 (e.g., the outer surface of the proximal end of the head technology in this embodiment) can form a close fit with the inner surface of the neck component 6, so that the head component 42 rides inside the neck component 6 to maintain the coaxial relationship between the rotation axis of the head component 42 and the longitudinal axis 46. In this embodiment, the distal end of the head component 42 protrudes distally from the distal end 64 of the neck component 6 and includes the aforementioned connection feature structure 44 for connecting to the acetabular reamer. The distal end of the head component 42 can be substantially cylindrical and can have a larger diameter than the proximal end of the head component 42 that rotates in the neck component 6. In this embodiment, the distal end of the head component 42 has the same outer diameter as the distal end 62 of the neck component 6 , so that the distal end of the head component 42 is flush with the outer surface of the distal end 62 of the neck component 6 .

[0074] In embodiments where the shaft 20 includes one or more bends, the shaft segments may have different lengths (as measured along their longitudinal axes). For example, in this embodiment, the distal shaft segment 20A is shorter than the additional shaft segment 20B. The head component 42 may be shorter than the shaft segments (as measured along their longitudinal axes 46).

[0075] As previously described, the proximal end 62 of the neck component 6 is pivotally connected to the distal end 32 of the shaft 20. In this embodiment, the pivot connection 70 is formed by a pair of holes 72 located at the distal end 32 of the shaft 20 and a pair of corresponding holes 7 located on the neck component 6, through which the bolt 74 passes. The rotation axis 76 provided by the pivot connection 70 is generally perpendicular to both the longitudinal axis 46 of the neck component 6 and the longitudinal axis 26 of the distal end 32 of the shaft 20 (e.g., the distal shaft segment 20A). Figure 7 As shown, the hole 72 can be located at the end of a pair of arms 36 extending distally from the end of the shaft 20. These arms 36 can provide clearance between the hollow cylindrical portion of the shaft 20 and the proximal end 62 of the neck component 6 to allow the shaft 20 and the neck component 6 to rotate relative to each other about the pivot connection 70.

[0076] The pivot connection 70 between the neck component 6 and the shaft 20 can allow the shaft 20 to be tilted relative to the longitudinal axis 46 of the neck component 6. Such tilting of the shaft 20 relative to the longitudinal axis 46 of the neck component 6 can allow viewing of the acetabulum and / or a portion of the reamer 100 that would otherwise be obscured by the reamer handle 10. This can, for example, allow the surgeon to better view and determine the depth of reaming the acetabulum without having to remove the reamer 100 and reamer handle 10 from the acetabulum or detach the reamer handle 10 from the reamer. Figure 4 The acetabular reamer handle 10 is shown in this embodiment in a non-tilted state. Figure 5 and Figure 6 The shaft 20 is shown tilted (counterclockwise as viewed in these figures) such that the size of the angle between the longitudinal axis 46 of the neck component 6 and the longitudinal axis 26 of the distal shaft section 20A is increased. Figure 4 and Figure 5 and Figure 6 By comparison, it should be appreciated that tilting the shaft 20 in this manner may allow for exposure of portions of the acetabulum and / or reamer 100 that are located beneath the shaft 20 .

[0077] It is noted that the universal joint 48A of the drive train 40 is positioned to coincide with the pivot connection 70 between the distal end 32 of the shaft 20 and the proximal end 62 of the neck component 6. This can allow for angling of the shaft 20 relative to the longitudinal axis 46 of the neck component 6 to be accommodated. As described herein, such angling of the shaft 20 relative to the longitudinal axis of the neck component 6 can exist in the untilted state of the acetabular reamer handle 10 (e.g., due to the angling of the engagement surface 8 as will be described below). The universal joint 48A can also accommodate relative rotation of the shaft 20 and the neck component 6 about the pivot connection 70 to tilt the shaft as described above.

[0078] In addition to Figure 5 and 6 In addition to the tilting of the shaft 20 shown, it is contemplated that the shaft 20 may also be tilted about the longitudinal axis 46 of the neck component 6 (i.e., in a clockwise direction or a counterclockwise direction when viewed along the longitudinal axis 46 from the surgeon's perspective) to again view the acetabulum and / or a portion of the reamer that was originally obscured by the reamer handle 10.

[0079] The pivot connection 70 between the neck component 6 and the distal end 32 of the shaft 20 may include a locking mechanism. The locking mechanism may be used to resist undesired tilting of the shaft 20 relative to the longitudinal axis 46 of the neck component 6. In this way, the relative orientation of the neck component 6 and the shaft 20 may be fixed in place while the patient's acetabulum is being reamed. As will be described in detail below, the locking mechanism may be simple to operate and may have a compact, robust configuration that does not need to include complex parts that would otherwise increase the cost of the reamer handle 10 and / or reduce the reliability of the reamer handle.

[0080] In this embodiment, the locking mechanism includes an engagement member 50 having an engagement surface 51. By comparing, for example, FIGS. 1 and Figure 7 It will be appreciated that the engagement surface 51 is substantially circumferential relative to the longitudinal axis of the hollow shaft at the distal end of the shaft (in this embodiment, the axis corresponds to the longitudinal axis 26 of the distal shaft segment 20A). The engagement member 50 is located at the distal end 32 of the shaft 20. In this embodiment, the engagement surface 51 is substantially annular. It is also contemplated that the engagement surface may have a different shape (e.g., triangular, rectangular, pentagonal, or hexagonal). The engagement member 50 may be substantially tubular and may have a cross-sectional shape corresponding to the shape of the engagement surface 51.

[0081] The drive train 40 may pass through the center of the engagement member 50. The engagement member 50 may be mounted inside or outside the shaft 20. In one embodiment, the engagement member 50 may be mounted as a sleeve on the outer surface of the distal shaft section 20A.

[0082] In the present embodiment, the engagement member 50 is slidably mounted inside the shaft 20 and protrudes from the distal end 32 of the shaft 20 to engage with the proximal end 62 of the neck component 6 .

[0083] The engagement member 50 is movable distally to push the engagement surface 51 against the proximal end of the neck component 6 to resist tilting of the shaft 20 relative to the longitudinal axis 46 of the neck component 6 .

[0084] In one embodiment, the engagement member 50 may be mounted on a thread (comprising a first thread on the shaft and a second thread on the engagement member 50) to allow the engagement member to be moved distally (by rotation of the engagement member 50 about the thread in a first direction) so as to push the engagement surface 51 against the proximal end of the neck component 6. By rotating the engagement member 50 in a second direction opposite to the first direction, the engagement member 50 may be moved proximally so that the engagement surface 51 is disengaged from the proximal end of the neck component 6.

[0085] In other embodiments, the engagement member 50 may be resiliently biased distally to push the engagement surface 51 against the proximal end of the neck component 6. For example, in the present embodiment, the locking mechanism includes a spring, such as a coil spring 80. The coil spring 80 may be coaxially mounted relative to the distal end 32 of the shaft 20 and proximally mounted relative to the engagement member 50. In an embodiment in which the engagement member 50 is mounted as a sleeve on the outside of the shaft 20, the coil spring 80 may also be mounted on the outside of the shaft 20. In the present embodiment, the coil spring 80 is located inside the shaft 20 together with the engagement member 50. As shown in the figure, the coil spring 80 in this embodiment is located between the engagement member 50 and a circumferential lip 56 provided on the inner surface of the shaft 20 (for example, Figure 4 ). Thus, the coil spring 80 is arranged to bias the engagement member 50 distally such that the engagement member protrudes from the distal end 32 of the shaft 20, as described above.

[0086] In use, the engagement surface 51 of the engagement member 50 is urged (e.g. by a spring of the locking mechanism) against the proximal end 62 of the neck component 6. This resists any pivoting movement of the neck component 6 relative to the shaft 20 (including tilting of the shaft 20 discussed above).

[0087] In this embodiment, the proximal end 62 of the neck component 6 is provided with an engagement surface 8, against which the engagement surface 51 of the engagement member 50 can be pressed to resist the above-mentioned tilting of the shaft 20. The engagement surface 8 and the engagement surface 51 can be substantially flat to provide a stable and secure contact therebetween.

[0088] As can be seen from the figure, in this embodiment, the engagement surface 8 of the neck component 6 can be set to form a certain angle with the longitudinal axis 46. Specifically, the engagement surface 8 can be contained in a plane having a surface normal that is oriented at a non-zero angle α relative to the longitudinal axis 46 of the neck component 6. Typically, α can be less than 90° to allow proper operation of the universal joint 48A of the drive train 40. The angling of the neck component 6 relative to the shaft 20 can allow the surgeon to more easily work around the soft tissue in the incision site. In a non-tilted position of the longitudinal axis 26 of the distal end 32 of the shaft 20 (e.g. Figure 1A ), the longitudinal axis may be parallel to the surface normal of the joining surface 8.

[0089] In some embodiments, 30°≤α≤60°. In some embodiments, α is about 30°. In some embodiments, α is about 45°.

[0090] It should be noted that in embodiments where the shaft 20 includes a bend, such as the bend 28, the (non-oblique) angling of the neck component 6 relative to the shaft 20 and the bend 28 may be combined to configure the acetabular reamer handle 10 as an offset reamer handle. It is contemplated that the angles α and β may be equal in size and opposite in direction to form a dog-leg arrangement in which the longitudinal axis 46 of the neck component 6 is substantially parallel to the longitudinal axis 66 of the proximal shaft segment 20B.

[0091] According to an alternative embodiment, it is contemplated that the engagement surface 8 of the neck component 6 may be contained in a plane having a surface normal that is found oriented parallel to the longitudinal axis 46 of the neck component 6. This may allow the acetabular reamer shank 10 to operate as a straight reamer shank (although the reamer shank can be tilted as described herein).

[0092] In order to release the engagement surface 51 from the proximal end 62 of the neck component 6, the engagement member 50 can be retracted in the proximal axial direction against the bias provided by the spring 80. The engagement member 50 may include or be connected to a handle 52, which may include one or more gripping surfaces. The handle 52 can be grasped by the surgeon and retracted in the proximal direction to retract the engagement member 50. In the present embodiment, the handle 52 is connected to the engagement member 50 by a pair of arms 54 extending substantially parallel to the distal end 32 of the shaft 20. The arms 54 extend through corresponding holes 55 in the wall of the shaft 20, whereby the handle 52 can be located outside the shaft 20 for the surgeon to operate.

[0093] When the proximal end 62 (e.g., the engagement surface 8) is released from the engagement surface 51 by retraction of the engagement member 50, the neck component 6 and the shaft 20 are free to pivot about the pivot connection 70, whereby the shaft 20 can be freely tilted as described herein to view portions of the acetabulum and / or reamer 100 that may otherwise be obscured. After viewing the acetabulum and / or reamer, the surgeon can return the shaft 20 to its initial position (e.g., with the longitudinal axis 26 of the distal end 32 of the shaft 20 parallel to the surface normal of the engagement surface 8) and release the handle 52, so that the engagement surface 51 reengages and presses against the proximal end 62 of the neck component 6. In this way, the surgeon can resume reaming while the shaft 20 is locked to prevent undesired tilting.

[0094] Figure 8 and Fig. 9 Components positioned toward the distal end 32 of the shaft 20 of the acetabular reamer handle 10 are shown according to another embodiment of the present invention. Figure 8 and Fig. 9 The embodiment of FIG. 1 to FIG. 2 is similar in many respects to FIG. Figure 7 , and only the differences therebetween will be described in detail below. Figure 3and Figure 4 as well as Figure 5 and Figure 6 similar, Figure 8 and Fig. 9 The acetabular reamer handle 10 is shown in a non-tilted configuration ( Figure 8 ) for hole enlargement and in an inclined configuration ( Fig. 9 ) for viewing the acetabulum and / or the portion of the reamer 100 that would otherwise be obscured by the acetabulum reamer handle 10.

[0095] In this embodiment, the acetabular reamer handle 10 includes one or more locking members 58. The locking members 58 extend distally from the substantially annular engagement surface 51 of the engagement member 50. Figure 8 As shown, the locking members 58 can be received in corresponding openings 88 located in the proximal end 62 of the neck component 6 (e.g., in the engagement surface 8). The locking members 58 and the openings 88 can cooperate to lock the engagement surface 51 on the proximal end 62 of the neck component 6. Specifically, due to the distally protruding orientation of the locking members 58, when the locking members 58 are located in their corresponding openings 88, any attempt to tilt the shaft 20 relative to the longitudinal axis 46 of the neck component 6 causes the locking members 58 to be laterally pressed against the sidewalls of their corresponding openings 88. Therefore, when the locking members 58 are received in their corresponding openings 88, these locking members can resist tilting of the shaft 20. Conversely, when the engagement member 50 is retracted proximally as described above, the locking members 58 are withdrawn from their corresponding openings 88, whereby the shaft 20 can be moved as described above. Fig. 9 Tilt as shown.

[0096] The cross-section of the locking member 58 can be triangular, wherein the apex of the triangle points distally. In the present embodiment, the apex of the substantially triangular locking member 58 points distally along the longitudinal axis 26 of the distal shaft segment 20A. The opening 88 can have an inner surface conforming to the shape of its corresponding locking member 58.

[0097] Where more than one such locking member 58 is provided, the locking members 58 may be distributed (e.g., evenly distributed) around the perimeter formed by the engagement surface 51 of the engagement member 50. For example, the acetabular reamer 10 may include two locking members 58, one on either side of a plane containing the longitudinal axis 46 of the hollow shaft 20 and the hollow neck component 6.

[0098] The acetabular reamer handle 10 according to an embodiment of the present invention may be included in a surgical kit. The kit may also include one or more acetabular reamer 100 of different sizes that can be connected to the head component of the drive train of the acetabular reamer handle.

[0099] In one embodiment, a method of reaming a patient's acetabulum may include connecting an acetabular reamer 100 to a reamer handle 10 of the type described above. The method may also include inserting the acetabular reamer 100 into the patient's acetabulum. The method may also include operating the acetabular reamer 100 to remove bone from the surface of the acetabulum. The method may also include tilting the shaft 20 relative to the longitudinal axis 46 of the neck component 6 with the acetabular reamer 100 in the acetabulum to view a portion of the acetabulum and / or the acetabular reamer 100 that was originally obscured by the reamer handle 10. The method may also include tilting the reamer handle 10 about the longitudinal axis 46 of the neck component to view a portion of the acetabulum and / or the acetabular reamer 100 that was originally obscured by the reamer handle 10. By viewing the portion of the acetabulum and / or the acetabular reamer 100 that was originally obscured by the reamer handle 10, the depth of the reaming may be determined.

[0100] The method may further include operating the locking mechanism of the reamer shank 10 to disengage the engagement member 50 of the locking mechanism from the proximal end of the head component 42 to allow the aforementioned tilting of the shaft 20 relative to the longitudinal axis 46 of the neck component.

[0101] The method may also include manually retracting the engagement member 50 in a proximal direction to release the engagement member 50 from the proximal end 62 of the neck component 6, as described in more detail above.

[0102] Thus, an acetabular reamer handle has been described, the acetabular reamer handle comprising a shaft having a distal end, a neck component having a longitudinal axis, a drive train extending through the shaft and the neck component, and a locking mechanism. The distal head component of the drive train is mounted for rotation around the longitudinal axis of the neck component and can be connected to a reamer. The distal end of the shaft and the proximal end of the neck component are pivotally attached to allow the shaft to be tilted relative to the longitudinal axis. The tilt allows viewing of the acetabulum and / or the reamer that would otherwise be obscured. The locking mechanism includes an engagement member having an engagement surface located at the distal end of the shaft. The engagement member can be moved distally to push the engagement surface onto the proximal end of the neck component.

[0103] Although specific embodiments of the invention have been described, it will be appreciated that numerous modifications / additions and / or supplements may be made within the scope of the invention as claimed.

Claims

1. An acetabular reaming drill handle, the acetabular reaming drill handle comprising: a hollow shaft having a distal end; a hollow neck member having a longitudinal axis; a drive train extending through the shaft and the neck component, wherein a distally located head component of the drive train is mounted for rotation about the longitudinal axis of the neck component and is connectable to an acetabular reamer, and wherein the distal end of the shaft and the proximal end of the neck component are pivotally attached to allow the shaft to be tilted relative to the longitudinal axis of the neck component; as well as a locking mechanism comprising an engagement member having an engagement surface at the distal end of the shaft, wherein the engagement surface is substantially circumferential relative to a longitudinal axis of the hollow shaft at the distal end of the shaft, and wherein the engagement member is movable distally to urge the engagement surface against the proximal end of the neck component to resist the tilting of the shaft relative to the longitudinal axis of the neck component; wherein the proximal end of the neck component includes a surface for engaging the engagement surface of the engagement member, wherein the surface of the proximal end of the neck component is contained in a plane having a surface normal; as well as Wherein in a non-inclined position of the longitudinal axis of the distal end of the hollow shaft, the longitudinal axis of the distal end of the hollow shaft is parallel to the surface normal of the surface of the proximal end of the neck component. 2 . The acetabular reamer handle of claim 1 , wherein the surface normal is oriented at a non-zero angle α relative to the longitudinal axis of the neck component, wherein α<90°.

3. The acetabular reamer drill handle according to claim 2, wherein 30°≤α≤60°.

4. The acetabular reamer handle of claim 3, wherein α is approximately 30°.

5. The acetabular reamer handle of claim 3, wherein α is approximately 45°.

6. The acetabular reamer handle of claim 1, wherein the surface normal is oriented parallel to the longitudinal axis of the neck component.

7. The acetabular reamer handle of claim 1, wherein the engagement member is slidably mounted inside the hollow shaft and is configured to protrude from the distal end of the hollow shaft to push the engagement surface onto the proximal end of the neck component.

8. The acetabular reamer handle of claim 1, wherein the engagement member is resiliently biased distally to urge the engagement surface against the proximal end of the neck component.

9. The acetabular reamer handle of claim 8, wherein the locking mechanism comprises a coil spring mounted coaxially with respect to the distal end of the hollow shaft and proximally with respect to the engagement member.

10. The acetabular reamer handle according to claim 9, wherein the coil spring is mounted inside the hollow shaft.

11. The acetabular reamer handle of claim 1, wherein the engagement member comprises a handle component for manually retracting the engagement member in a proximal direction to release the engagement surface from the proximal end of the neck component.

12. An acetabular reamer drill shank according to claim 1, comprising one or more locking members extending from the engagement surface to be received in one or more corresponding openings in the proximal end of the neck component for locking the engagement surface on the proximal end of the neck component to resist the tilting of the shaft relative to the longitudinal axis of the neck component.

13. The acetabular reamer handle of claim 1, wherein the drive train includes a universal joint at a pivot point between the distal end of the shaft and the proximal end of the neck component.

14. The acetabular reamer shank of claim 1, wherein the acetabular reamer shank is an offset acetabular reamer shank, wherein the hollow shaft comprises a proximal shaft section and a distal shaft section, wherein the shaft has a bend at an interface between the proximal shaft section and the distal shaft section.

15. The acetabular reamer handle of claim 14, wherein the proximal and distal shaft sections are rigidly formed, whereby an angle between the longitudinal axis of the distal shaft section and the longitudinal axis of the proximal shaft section is fixed.

16. An acetabular reamer handle according to any preceding claim, wherein the engagement surface is substantially annular, triangular, rectangular, pentagonal or hexagonal.

17. A surgical kit comprising an acetabular reamer handle according to any preceding claim and one or more acetabular reamer of different sizes connectable to the head component of the acetabular reamer handle.

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