Orthopedic instruments and systems for the placement of cementless femoral stem components in direct anterior approach hip replacement surgery.

Abstract

An orthopedic system for use in direct anterior approach orthopedic hip replacement procedures for the femur of a patient includes a stem insertion device (12) having an offset locking shaft (68) for placing a cementless femoral stem (14) component into the surgically prepared intramedullary canal of the patient.

Description

Technical Field

[0001] The present disclosure generally relates to orthopedic instruments, and more particularly to orthopedic instruments used in direct anterior approach hip replacement surgical procedures.

Background Art

[0002] Arthroplasty is a well-known surgical procedure in which a diseased and / or damaged living joint is replaced with an artificial joint. The artificial joint may include a prosthesis implanted in one or more of the patient's bones. Many hip prostheses include a femoral prosthesis implanted in the patient's femur. The femoral prosthesis typically includes an elongated stem component disposed within the intramedullary canal of the patient's femur and a spherical head component that abuts against the patient's acetabulum or an artificial replacement acetabular cup.

[0003] Some hip replacement procedures are performed using a direct anterior approach. When using the direct anterior approach, the surgeon cannot see through the intramedullary canal of the patient's femur. Due to such restricted access and visibility, it becomes difficult for the surgeon to install certain components, such as a cementless femoral stem component, using instruments designed for other approaches (e.g., posterior approach).

Summary of the Invention

Means for Solving the Problems

[0004] In one embodiment, an orthopedic instrument for implanting a femoral stem component during a direct anterior approach orthopedic hip replacement surgery to a patient's femur includes a stem insertion device. The stem insertion device includes an impact plate defining the proximal end of the stem insertion device and a grip extending from the distal end of the impact plate. The longitudinal axis of the grip extends through the center of the impact plate. The grip includes an outer surface configured to grip during the insertion of the impact plate. The stem insertion device also includes an elongated body extending from the distal end of the grip and a locking mechanism captured within the elongated body. The locking mechanism includes a knob rotatable relative to the elongated body and a locking shaft fixed to the distal surface of the knob and extending through the elongated body, the threaded distal end of the locking shaft extending outward through an opening formed in the distal end of the elongated body. The threaded distal end of the locking shaft is configured to be screwed into and received by a threaded hole formed in the femoral stem component. The longitudinal axis of the grip and the longitudinal axis of the locking shaft define an offset angle of 10 to 30 degrees.

[0005] In one embodiment, the offset angle defined by the longitudinal axis of the grip and the longitudinal axis of the locking shaft is 10 to 20 degrees.

[0006] In an exemplary embodiment, the offset angle defined by the longitudinal axis of the grip and the longitudinal axis of the locking shaft is approximately 12 degrees.

[0007] The stem insertion device may further include an auxiliary extraction plate. The auxiliary extraction plate includes an extraction surface facing the distal end of the elongated body, which extends inward away from the proximal end of the elongated body and is configured to be embedded during the extraction of the femoral stem component.

[0008] In one embodiment, when the threaded distal end of the locking shaft is positioned within the threaded hole of the femoral stem component, rotation of the knob causes rotation of the locking shaft, selectively screwing the threaded distal end of the locking shaft into the threaded hole of the femoral stem component. In such an embodiment, when the threaded distal end of the locking shaft is positioned within the threaded hole of the femoral stem component, rotation of the knob in a first direction causes the threaded distal end of the locking shaft to screw into the threaded hole of the femoral stem component, while rotation of the knob in the opposite direction causes the threaded distal end of the locking shaft to disengage from the threaded hole of the femoral stem component, allowing the locking shaft to be removed therefrom.

[0009] In another embodiment, an orthopedic system for use in a direct anterior approach orthopedic hip replacement surgery for a patient's femur includes an implantable femoral stem component and a stem insertion device. The femoral stem component is configured to be implanted into a surgically prepared intramedullary canal of the patient's femur and includes a longitudinal axis extending upward / downward through the femoral stem component, along with an elongated threaded hole having an upper end that opens to the upper surface of the femoral stem component. The stem insertion device includes an impact plate defining the proximal end of the stem insertion device and a grip extending from the distal end of the impact plate. The longitudinal axis of the grip extends through the center of the impact plate. The grip also includes an outer surface configured to grip the shaft during insertion of the impact plate. The stem insertion device also includes an elongated body extending from the distal end of the grip and a locking mechanism captured within the elongated body. The locking mechanism includes a knob rotatable relative to an elongated body and a locking shaft fixed to the distal surface of the knob, the threaded distal end of the locking shaft extending outward through an opening formed in the distal end of the elongated body and entering the threaded hole of the femoral stem component. When the threaded distal end of the locking shaft of the stem insertion device is positioned within the threaded hole of the femoral stem component, the longitudinal axis of the grip and the longitudinal axis of the locking shaft define an offset angle of 10 to 30 degrees, and the longitudinal axis of the grip is aligned with the longitudinal axis of the femoral stem component.

[0010] In one embodiment, when the threaded distal end of the locking shaft of the stem insertion device is positioned within the threaded hole of the femoral stem component, the offset angle defined by the longitudinal axis of the grip and the longitudinal axis of the locking shaft is 10 to 20 degrees.

[0011] In an exemplary embodiment, when the threaded distal end of the locking shaft of the stem insertion device is positioned within the threaded hole of the femoral stem component, the offset angle defined by the longitudinal axis of the grip and the longitudinal axis of the locking shaft is approximately 12 degrees.

[0012] In another embodiment, when the threaded distal end of the locking shaft of the stem insertion device is positioned within the threaded hole of the femoral stem component, the longitudinal axis of the locking shaft is aligned with the longitudinal axis of the threaded hole of the femoral stem component.

[0013] In an exemplary embodiment, when the threaded distal end of the locking shaft is positioned within the threaded hole of the femoral stem component, rotation of the knob in a first direction engages the threaded distal end of the locking shaft with the threaded hole of the femoral stem component, while rotation of the knob in the opposite direction disengages the threaded distal end of the locking shaft from the threaded hole of the femoral stem component, allowing the locking shaft to be removed therefrom.

[0014] The stem insertion device may also include an auxiliary extraction plate extending inward away from the proximal end of the elongated body. The auxiliary extraction plate may include an extraction surface facing the femoral stem component when the threaded distal end of the locking shaft of the stem insertion device is positioned within the threaded hole of the femoral stem component, and such an extraction surface is configured to be fitted during the extraction of the femoral stem component.

[0015] In another embodiment, a method for implanting a femoral stem component during the performance of a direct anterior approach orthopedic hip replacement surgery on a patient's femur includes surgically preparing the proximal end of the patient's femur to create a resected plane. The method also includes defining an offset angle of 10 to 30 degrees between the longitudinal axis of the grip of the stem insertion device and the longitudinal axis of the threaded hole formed in the femoral stem component, and screwing the threaded distal end of the locking shaft of the stem insertion device into the threaded hole formed in the femoral stem component so that the longitudinal axis of the grip of the stem insertion device is aligned with the longitudinal axis of the femoral stem component. The distal end of the femoral stem component is then advanced into the intramedullary canal of the patient's femur through the surgically prepared proximal end of the patient's femur. Next, an impact plate on the proximal end of the stem insertion device is fitted to implant the femoral stem component into the intramedullary canal of the patient's femur.

[0016] The method may also include, after the stem insertion device has been fitted into the impact plate, unscrewing the threaded distal end of the locking shaft of the stem insertion device from the threaded hole of the femoral stem component, and then advancing the stem insertion device proximal to the intramedullary canal of the patient's femur.

[0017] In one embodiment, the offset angle defined by the longitudinal axis of the grip of the stem insertion device and the longitudinal axis of the threaded hole of the femoral stem component is 10 to 20 degrees.

[0018] In an exemplary embodiment, the offset angle defined by the longitudinal axis of the grip of the stem insertion device and the longitudinal axis of the threaded hole of the femoral stem component is approximately 12 degrees.

[0019] In one embodiment, the threaded distal end of the locking shaft of the stem insertion device is screwed into a threaded hole formed within the femoral stem component by rotating a knob fixed to the locking shaft, thereby rotating the threaded distal end of the locking shaft and inserting it into the threaded hole of the femoral stem component.

[0020] In another embodiment, the method includes removing the femoral stem component from the intramedullary canal of the patient's femur by fitting into an auxiliary extraction plate that extends inwardly away from the distal end of the grip of the stem insertion instrument.

Brief Description of the Drawings

[0021] For a detailed description, reference is particularly made to the following drawings. [Figure 1] It is a side elevation view of a stem insertion instrument of an orthopedic system used in a direct anterior approach total hip arthroplasty for the patient's femur. [Figure 2] It is a side elevation view of a cementless femoral stem component. [Figure 3] It is a side elevation view of a cementless femoral stem component. [Figure 4] It is a cross-sectional view of the cementless femoral stem components of FIGS. 2 and 3 as viewed from the direction of the arrow along line 4-4 of FIG. 2. [Figure 5] It is a view similar to FIG. 1, but showing the locking mechanism removed from the elongated body of the stem insertion instrument. [Figure 6] It is a side elevation view showing the stem insertion instrument of FIG. 1 fixed to the femoral stem components of FIGS. 2 to 4. Note that a portion of the proximal end of the femoral stem component has been cut away for clarity of explanation. [Figure 7] It is a cross-sectional view of the patient's femur during a direct anterior approach total hip arthroplasty procedure, showing where the surgeon is introducing the femoral stem components of FIGS. 2 to 4 using the stem insertion instrument of FIG. 1. [Figure 8] It is a view similar to FIG. 7, but showing the femoral stem component fitted into the bone tissue of the intramedullary canal of the patient's femur.

Modes for Carrying Out the Invention

[0022] While the concepts of the present disclosure are susceptible to various modifications and alternative forms, specific exemplary embodiments thereof are shown by way of example in the drawings and are described in detail herein. It is to be understood, however, that the present disclosure is not intended to be limited to the particular forms disclosed, but on the contrary, is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.

[0023] Terms such as anterior, posterior, medial, lateral, superior, inferior, etc., which represent anatomical directions, may be used throughout this specification with respect to the orthopedic implants or prostheses and surgical instruments described herein, as well as with respect to the natural anatomical structures of a patient. Such terms have meanings that are well understood in both the study of anatomy and the field of orthopedic surgery. The use of such anatomical directional terms in the description and claims is intended to be consistent with their well-understood meanings unless otherwise specified.

[0024] Referring to FIGS. 1 - 4, an orthopedic system 10 is illustratively embodied to include an insertion instrument 12 and a femoral stem component, specifically a cementless femoral stem component 14. As will be discussed in more detail below, the insertion instrument 12 is used to place the femoral stem component 14 within the intramedullary canal of a patient's femur during a direct anterior approach total hip arthroplasty procedure.

[0025] As shown in Figures 2 to 4, the femoral stem component 14 is configured to be implanted in the patient's femur 106 during hip replacement surgery. Specifically, the femoral stem component 14 is implanted in a surgically prepared (e.g., reamed) intramedullary canal 104 of the patient's femur 106. The femoral head component (not shown) is fixed to a trunnion 16 formed at the end of the elongated neck 18 of the femoral stem component 14. When placed on the femoral stem component 14, the femoral head component is positioned to be supported by either the patient's biological acetabulum or an artificial acetabular component implanted in the patient's pelvis to replace the patient's acetabulum. In this configuration, the femoral stem component 14 and the biological or artificial acetabulum function collectively as a system to replace the biological joint of the patient's hip.

[0026] The proximal body 20 defines the middle portion of the femoral stem component 14. Thus, the elongated neck 18 extends upward and medially away from the proximal body 20, and the tapered trunnion 16 is formed at the upper / medial end of the neck 18, i.e., opposite the end that engages with the proximal body 20. The tapered stem 22 extends downward away from the opposite end of the proximal body 20. The tapered stem 20 has a rounded distal end 24 that defines the lowest surface of the femoral stem component 14. As can be seen in Figure 4, a threaded hole 26 is formed in the lateral shoulder 28 of the proximal body. As will be discussed in more detail below, the threaded hole 26 receives the distal end of the threaded shaft of the insertion device 12 by screwing it in during the installation (or removal) of the femoral stem component 14.

[0027] In the exemplary embodiments described herein, the femoral stem component 14 is embodied as a cementless femoral stem, i.e., a stem that is implanted without the use of bone cement. Furthermore, the femoral stem component 14 is embodied as a monolithic metal structure. The femoral stem component 14 may be constructed from implant-grade biocompatible metal, but other materials may also be used. Examples of such metals include cobalt, including cobalt alloys such as cobalt-chromium alloy; titanium, including titanium alloys such as Ti6Al4V alloy; and stainless steel. Such metal femoral stem components 14 may also be coated with surface treatments such as hydroxyapatite to enhance biocompatibility. Furthermore, the surfaces of the femoral stem component 14 that engage with biological bone, such as the outer surfaces of the proximal body 20 and the tapered stem 22, may be textured to facilitate fixation of the component to the bone. Such surfaces may also be porous coated to promote internal bone growth for permanent fixation.

[0028] As can be seen in Figure 4, the screw hole 26 of the femoral stem component 14 is angled inward. In particular, as can be seen in Figure 4, the femoral stem component 14 has a longitudinal axis 30 that extends vertically. As can be seen in Figure 4, the longitudinal axis 32 of the screw hole 26 also extends generally vertically, but is angled inward. Therefore, the longitudinal axis 32 of the screw hole 26 and the longitudinal axis 30 of the femoral stem component 14 define an offset angle θ. In exemplary embodiments described herein, the offset angle θ of the screw hole 26 is 10 to 30 degrees. In another exemplary embodiment, the offset angle θ of the screw hole 26 is 10 to 20 degrees. In a specific exemplary embodiment, the offset angle θ of the screw hole 26 is 12 degrees. By offsetting the screw hole 26 inward in this way, the stem insertion device 12 facilitates the placement of the femoral stem component 14 "very close" to the proximal end 108 of the patient's femur 106, even though the intramedullary canal 104 cannot be seen during direct anterior approach hip arthroplasty (see Figures 7 and 8).

[0029] As can be seen in Figure 1, the insertion device 12 has an impact plate 40 at its proximal end. The distal end of the elongated body 42 defines the distal end of the stem insertion device 12. The locking mechanism 44 is captured within the elongated body 42 of the device. The locking mechanism 44 is operable to lock the stem insertion device 12 to the femoral stem component 14 during implantation (or removal) of the stem component.

[0030] In the exemplary embodiments described herein, the impact plate 40 of the stem insertion instrument 12 includes a rounded metal impact surface 46 formed at the proximal end of the impact plate 40. During use, the surgeon holds the stem insertion instrument 12 via the grip 48 and drives the femoral stem component 14 into the surgically prepared proximal end of the patient's femur by striking the impact surface 46 with a surgical hammer, sledge, or other insertion tool (discussed in more detail below). The impact plate 40 also includes a pair of flanges 52 extending radially outward from its center. The flanges 52 serve to protect the surgeon's hand over the grip 48 during insertion. Furthermore, if the stem insertion instrument 12 is used to extract the femoral stem component 14, the flanges 52 can be inserted from their lower surfaces 54.

[0031] As can be seen in Figure 1, the grip 48 extends distally from the distal end of the impact plate 40. The grip 48 includes an outer surface 56 that is sized and molded to be grasped by the surgeon during the insertion of the instrument's impact plate 40. As can be seen in Figure 1, the longitudinal axis 58 of the grip 48 passes through the center of the impact plate 40. In this way, the surgeon can use the grip 48 to precisely center the impact plate 40 during insertion. As can also be seen in Figure 1, the elongated body 42 extends distally away from the distal end of the grip 48. A hole 60 extends through the elongated body 42. Specifically, the hole 60 extends between an opening 62 formed at the proximal end of the elongated body 42 and an opening 64 formed at the opposite distal end of the elongated body 42.

[0032] The locking mechanism 44 includes a knob 66 ​​rotatable relative to an elongated body 42 and a locking shaft 68 fixed to the distal surface of the knob 66. The locking shaft 68 extends away from the knob 66 ​​and includes a threaded distal end 70. The threaded distal end 70 is sized and shaped to screw into a threaded hole 26 of the femoral stem component 14 in order to selectively lock the insertion device 12 to the femoral stem component 14. Specifically, the distal end 70 of the locking shaft 68 has a set of locking threads 72 defined therein. The locking threads 72 are configured to screw into a threaded hole 26 of the femoral stem component 14 in order to secure the insertion device 12 to the femoral stem component 14.

[0033] The locking mechanism 44 can be removably captured within the elongated body 42 of the stem insertion instrument 12, or can be fixed to the elongated body 42 in another way. Specifically, the threaded distal end 70 of the locking shaft 68 can be advanced into the proximal opening 62 of the elongated body 42, then advanced through the hole 60 of the elongated body, and then advanced out through the distal opening 64. Because the diameter of the knob 66 ​​is larger than the proximal opening 62 of the elongated body 42, the knob 66 ​​acts as a stopper during the installation of the locking shaft 68 into the hole 60 of the elongated body. Once the knob 66 ​​is positioned close to the proximal end of the elongated body 42, the threaded distal end 70 of the locking shaft 68 extends outward through the distal opening 64 of the body and enters the threaded hole 26 of the femoral stem component 14. When the surgeon or other user rotates the knob 66, the threads 72 of the locking shaft rotate accordingly. Rotation in one direction (e.g., clockwise) can be used to tighten and secure the stem insertion device 12 to the femoral stem component 14, while rotation in the opposite direction (e.g., counterclockwise) can be used to loosen and separate the stem insertion device 12 from the femoral component 14.

[0034] As can be seen in Figures 1 and 6, the hole 60 in the elongated body of the stem insertion device 12, and therefore the locking mechanism 44 captured therein, is angled inward. In particular, as described above and as can be seen in Figure 1, the longitudinal axis 58 of the grip 48 extends vertically and passes through the center of the impact plate 40. As can be seen in Figure 1, the longitudinal axis 74 of the locking shaft 68 also extends generally vertically, but is angled inward. Thus, the longitudinal axis 58 of the grip 48 and the longitudinal axis 74 of the locking shaft 68 define an offset angle α. The offset angle α of the locking shaft 68 coincides with the offset angle θ of the screw hole 26. Therefore, in the exemplary embodiments described herein, the offset angle α of the locking shaft 68 is 10 to 30 degrees. In another exemplary embodiment, the offset angle α of the locking shaft 68 is 10 to 20 degrees. In a specific exemplary embodiment, the offset angle α of the locking shaft 68 is 12 degrees. Such an inward offset of the locking shaft 68 allows the shaft 68 to be positioned in alignment with the threaded hole 26 of the femoral stem component 14. In other words, when the stem insertion device 12 is fixed to the femoral stem component 14, as shown in Figure 6, the longitudinal axis 74 of the locking shaft 68 is aligned with the longitudinal axis 32 of the threaded hole 26 of the femoral stem component 14. Such an arrangement also aligns the grip 48 with the femoral stem component 14. In particular, when the stem insertion device 12 is fixed to the femoral stem component 14, as shown in Figure 6, the longitudinal axis 58 of the grip 48 and the longitudinal axis 30 of the femoral stem component 14 are aligned with each other. Thus, despite the angled locking connection between the femoral stem component 14 and the device 12, a relatively high impact load transmission efficiency (i.e., impact load transmission efficiency = output / input) is achieved because the driving force is transmitted along a common axis.

[0035] As can be seen in Figures 1 and 6, the stem insertion device 12 also includes an auxiliary extraction plate 80. The auxiliary extraction plate 80 extends inward away from the proximal end of the elongated body 42. The auxiliary extraction plate 80 includes an extraction surface 82 facing the distal end of the elongated body 42 (i.e., the stem component 14 when the stem component is fixed to the stem insertion device 12). The extraction surface 82 is configured to be inserted by a surgical hammer, sledge, or other insertion tool during the extraction of the femoral stem component 14 to drive the femoral stem component 14 outward from the surgically prepared proximal end of the patient's femur. The use of the auxiliary extraction plate 80 is particularly useful during anterior surgical approaches, as the lower surface 54 of the flange 52 of the impact plate 40 may sometimes be close to, or in fact in contact with, soft tissue. Thus, the auxiliary extraction plate 80 provides an alternative insertion surface for use in place of the impact plate 40 in such situations.

[0036] As can be seen in Figures 1 and 5-8, the sides of the stem insertion device 12 are curved inward (i.e., curved inward). Specifically, the sides of the grip 48 and the elongated body 42 work together to define an arched concave surface that curves inward toward the opposite side (i.e., the inside) of the insertion device 12. This configuration provides clearance during the use of the stem insertion device 12. In particular, during direct anterior approach hip arthroplasty, the use of an insertion device with relatively straight sides can result in the device colliding with the greater trochanter of the patient's femur 106. In the case of the insertion device 12, the curved lateral surface provides clearance for the greater trochanter when the surgeon advances the assembled femoral stem component 14 and the stem insertion device 12 into the proximal end 108 of the patient's femur 106 around the greater trochanter.

[0037] In exemplary embodiments, the stem insertion device 12 is formed from a metal material such as stainless steel. In particular, the impact plate 40, grip 48, elongated body 42, and locking mechanism 44 form the assembled metal device. The stem insertion device 12 may be formed by conventional machining techniques, or alternatively, by the use of 3D printing techniques. In the case of 3D printing, the stem insertion device 12 is formed layer by layer.

[0038] When in use, the orthopedic system 10 may be used by a surgeon to implant a femoral stem component 14 into the intramedullary canal 104 of the patient's femur 106 during a direct anterior approach hip replacement surgery. Before implanting the femoral stem component 14, the surgeon performs several preoperative and intraoperative surgical steps to prepare the patient's femur 106 to receive the femoral stem component 14. For example, the surgeon surgically resects the patient's living femoral head using a bone saw to create a surgically prepared proximal end 108 of the patient's femur 106, including, among other features, the resected plane 102. The surgeon also assembles and places several trial components before implanting the femoral stem component 14 to test the fit and function of the component to be implanted.

[0039] Next, the surgeon selects a femoral stem component 14 of the desired size from among the various available sizes. Then, the surgeon installs the stem insertion device 12 into the selected femoral stem component 14. To do this, the surgeon first installs the locking mechanism 44 into the elongated body 42 of the insertion device 12 by advancing the threaded distal end 70 of the locking shaft 68 into the proximal opening 62 of the elongated body 42 and through the hole 60 of the elongated body, so that the threaded distal end 72 of the locking shaft 68 extends through the distal opening 64 of the body. The surgeon then inserts the threaded distal end 72 of the locking shaft 68 into the threaded hole 26 of the selected femoral stem component 14. The surgeon or other user then rotates the knob 66, and thus the threads 72 of the locking shaft, in a direction (e.g., clockwise) to tighten and thus secure the stem insertion device 12 to the femoral stem component 14, as shown in Figure 6.

[0040] As shown in Figure 7, once the insertion device 12 is secured to the femoral stem component 14, the surgeon advances the distal end 24 of the femoral stem component 14 into the intramedullary canal 104 through the surgically prepared proximal end 108 of the patient's femur 106. The surgeon grasps the grip 48 and biases it distally toward the surgically prepared proximal end 108 of the patient's femur 106. In doing so, the femoral stem component 14 is advanced distally and thus further into the intramedullary canal 104 of the patient's femur 106. During such advancement of the femoral stem component 14, as shown in Figure 7, the curved lateral configuration of the insertion device 12 facilitates the advancement of the femoral stem component 14 by the surgeon by providing a gap at the greater trochanter of the patient's femur 106.

[0041] The surgeon continues to advance the grip 48 (and thus the femoral stem component 14) distally into the intramedullary canal 104 of the patient's femur 106 until the stem component 14 engages with the bone tissue, thereby providing the surgeon with tactile indication that the femoral stem component 14 has reached the desired initial depth. As shown in Figure 8, once the femoral stem component 14 is positioned in this manner, the surgeon drives the femoral stem component 14 into the bone tissue by striking the impact plate 40 of the stem insertion instrument 12 with a surgical hammer, sledge, or other insertion tool until the femoral stem component 14 is fully seated within the intramedullary canal 104 of the patient's femur 106.

[0042] Once the femoral stem component 14 is implanted to the desired depth, the surgeon assesses whether the femoral stem component 14 is properly positioned within the intramedullary canal 104. If the surgeon is satisfied with the fit of the femoral stem component 14 within the intramedullary canal 104, the surgeon rotates the knob 66 ​​of the locking mechanism in a direction that loosens the stem insertion instrument 12 from the implanted femoral stem component 14 and thus separates it (for example, counterclockwise). The surgeon then pulls or biases the grip 48 away from the implanted femoral stem component 14, thereby releasing the threaded distal end 72 of the locking shaft 68 of the instrument from the threaded hole 26 of the stem component. Once thus released, the surgeon removes the insertion instrument 12 from the surgically prepared proximal end 108 of the patient's femur. The surgeon then performs the remaining steps of the surgical procedure.

[0043] If the surgeon determines that the femoral stem component 14 needs to be removed and / or repositioned, the surgeon may do so using the impact plate 40 and / or the auxiliary extraction plate 80. Specifically, with the stem insertion device 12 fixed to the implanted femoral stem component 14 (or, if the insertion device 12 had previously been removed from the stem component 14, re-fixed to the stem component 14), the surgeon may use a surgical hammer, sledge, or other insertion tool to insert the lower surface 54 of the flange 52 of the impact plate 40 to drive the femoral stem component 14 away from engagement with the bone tissue of the intramedullary canal 104 of the patient's femur 106. Furthermore, if the lower surface 54 of the flange 52 of the impact plate 40 is positioned near or in contact with soft tissue, the surgeon may use the auxiliary extraction plate 80 instead. To do so, the surgeon inserts the extraction surface 82 of the plate with a surgical hammer, sledgehammer, or other insertion tool to drive the femoral stem component 14 away from engagement with the bone tissue of the intramedullary canal 104 of the patient's femur 106. After the surgeon has extracted the femoral stem component 14 by using the impact plate 40 and / or the auxiliary extraction plate 80, the surgeon can use the stem insertion instrument 12 to reposition the femoral stem component 14 in the desired orientation as described above.

[0044] While the drawings and the above description have illustrated and illustrated the present disclosure in detail, such illustrations and descriptions are by their nature illustrative and should not be considered limiting, and merely illustrate illustrative embodiments. It is understood that all changes and modifications that fall within the spirit of the present disclosure should be protected.

[0045] This disclosure offers several advantages based on various features of the methods, apparatus, and systems described herein. It should be noted that alternative embodiments of the methods, apparatus, and systems of this disclosure do not include all of the features described, but still benefit from at least some of the advantages of such features. Those skilled in the art can easily independently implement methods, apparatus, and systems encompassing the spirit and scope of this disclosure as defined by the appended claims, incorporating one or more features of the present invention.

[0046] [Implementation Method] (1) An orthopedic instrument for implanting a femoral stem component during a direct anterior approach orthopedic hip replacement surgery on the patient's femur, It is equipped with a stem insertion device, and the stem insertion device is An impact plate defining the proximal end of the aforementioned stem insertion device, A grip extending from the distal end of the impact plate, wherein (i) the longitudinal axis of the grip extends through the center of the impact plate, and (ii) the grip has an outer surface configured to grip the impact plate during insertion, A long, slender body extending from the distal end of the aforementioned grip, A locking mechanism captured within the elongated body, comprising: (i) a knob rotatable relative to the elongated body; and (ii) a locking shaft fixed to the distal surface of the knob and extending through the elongated body, wherein the threaded distal end of the locking shaft extends outward through an opening formed in the distal end of the elongated body, and the threaded distal end of the locking shaft is configured to be screwed into and received in a threaded hole formed in the femoral stem component, the locking mechanism comprising: An orthopedic instrument wherein the longitudinal axis of the grip and the longitudinal axis of the locking shaft define an offset angle of 10 to 30 degrees. (2) The orthopedic instrument according to Embodiment 1, wherein the offset angle defined by the longitudinal axis of the grip and the longitudinal axis of the locking shaft is 10 to 20 degrees. (3) The orthopedic instrument according to Embodiment 1, wherein the offset angle defined by the longitudinal axis of the grip and the longitudinal axis of the locking shaft is approximately 12 degrees. (4) The stem insertion device further comprises an auxiliary extraction plate, The auxiliary extraction plate extends inward away from the proximal end of the elongated body, The orthopedic instrument according to Embodiment 1, wherein the auxiliary extraction plate has an extraction surface facing the distal end of the elongated body, which is configured to be inserted during the extraction of the femoral stem component. (5) The orthopedic instrument according to Embodiment 1, wherein rotation of the knob causes rotation of the locking shaft, thereby selectively screwing the threaded distal end of the locking shaft into the threaded hole of the femoral stem component when the threaded distal end of the locking shaft is positioned within the threaded hole of the femoral stem component.

[0047] (6) When the threaded distal end of the locking shaft is positioned within the threaded hole of the femoral stem component, the knob is rotated in the first direction so that the threaded distal end of the locking shaft is screwed into the threaded hole of the femoral stem component. The orthopedic instrument according to Embodiment 5, wherein rotation of the knob in the direction opposite to the first direction allows the threaded distal end of the locking shaft to be unscrewed from the threaded hole of the femoral stem component, thereby enabling the locking shaft to be removed therefrom. (7) An orthopedic system for use in orthopedic hip replacement surgery with a direct anterior approach to the femur of a patient, An implantable femoral stem component configured to be implanted in a surgically prepared intramedullary canal of the femur of the patient, comprising: (i) a longitudinal axis extending upward / downward through the femoral stem component; and (ii) an elongated threaded hole having an upper end that opens to the upper surface of the femoral stem component; A stem insertion device comprising: (i) an impact plate defining the proximal end of the stem insertion device; (ii) a grip extending from the distal end of the impact plate, wherein (a) the longitudinal axis of the grip extends through the center of the impact plate, and (b) the grip has an outer surface configured to grip the shaft during insertion of the impact plate; (iii) an elongated body extending from the distal end of the grip; and (iv) a locking mechanism captured within the elongated body, comprising (a) a knob rotatable relative to the elongated body, and (b) a locking shaft fixed to the distal surface of the knob, wherein the threaded distal end of the locking shaft extends outward through an opening formed in the distal end of the elongated body and enters the threaded hole of the femoral stem component; An orthopedic system in which, when the threaded distal end of the locking shaft of the stem insertion device is positioned within the threaded hole of the femoral stem component, (i) the longitudinal axis of the grip and the longitudinal axis of the locking shaft define an offset angle of 10 to 30 degrees, and (ii) the longitudinal axis of the grip is aligned with the longitudinal axis of the femoral stem component. (8) The orthopedic system according to Embodiment 7, wherein when the threaded distal end of the locking shaft of the stem insertion device is positioned within the threaded hole of the femoral stem component, the offset angle defined by the longitudinal axis of the grip and the longitudinal axis of the locking shaft is 10 to 20 degrees. (9) The orthopedic system according to Embodiment 7, wherein when the threaded distal end of the locking shaft of the stem insertion device is positioned within the threaded hole of the femoral stem component, the offset angle defined by the longitudinal axis of the grip and the longitudinal axis of the locking shaft is approximately 12 degrees. (10) The orthopedic system according to Embodiment 7, wherein when the threaded distal end of the locking shaft of the stem insertion device is positioned within the threaded hole of the femoral stem component, the longitudinal axis of the locking shaft is aligned with the longitudinal axis of the threaded hole of the femoral stem component.

[0048] (11) When the threaded distal end of the locking shaft is positioned in the threaded hole of the femoral stem component, the knob is rotated in the first direction so that the threaded distal end of the locking shaft is screwed into the threaded hole of the femoral stem component. The orthopedic system according to Embodiment 7, wherein rotation of the knob in the direction opposite to the first direction allows the threaded distal end of the locking shaft to be unscrewed from the threaded hole of the femoral stem component, thereby enabling the locking shaft to be removed therefrom. (12) The stem insertion device further comprises an auxiliary extraction plate, The auxiliary extraction plate extends inward away from the proximal end of the elongated body, The auxiliary extraction plate has an extraction surface that faces the femoral stem component when the threaded distal end of the locking shaft of the stem insertion device is positioned within the threaded hole of the femoral stem component. The orthopedic system according to Embodiment 7, wherein the extraction surface is configured to be fitted during the extraction of the femoral stem component. (13) A method for installing a femoral stem component during the performance of a direct anterior approach orthopedic hip replacement surgery on the femur of a patient, Surgically preparing the proximal end of the patient's femur to create a resected plane, (i) The longitudinal axis of the grip of the stem insertion device and the longitudinal axis of the screw hole formed in the femoral stem component define an offset angle of 10 to 30 degrees, and (ii) the threaded distal end of the locking shaft of the stem insertion device is screwed into the screw hole formed in the femoral stem component such that the longitudinal axis of the grip of the stem insertion device is aligned with the longitudinal axis of the femoral stem component. The distal end of the femoral stem component is advanced into the intramedullary canal of the patient's femur through the surgically prepared proximal end of the patient's femur, A method comprising inserting an impact plate on the proximal end of the stem insertion device to implant the femoral stem component into the intramedullary canal of the femur of the patient. (14) After inserting the impact plate of the stem insertion device, the threaded distal end of the locking shaft of the stem insertion device is unscrewed from the threaded hole of the femoral stem component, The method according to embodiment 13, further comprising advancing the stem insertion device proximal to the intramedullary canal of the femur of the patient. (15) The method according to Embodiment 13, wherein screwing the threaded distal end of the locking shaft of the stem insertion device into the threaded hole formed in the femoral stem component is performed such that the offset angle defined by the longitudinal axis of the grip of the stem insertion device and the longitudinal axis of the threaded hole in the femoral stem component is 10 to 20 degrees.

[0049] (16) The method according to Embodiment 13, wherein screwing the threaded distal end of the locking shaft of the stem insertion device into the threaded hole formed in the femoral stem component is performed such that the offset angle defined by the longitudinal axis of the grip of the stem insertion device and the longitudinal axis of the threaded hole in the femoral stem component is approximately 12 degrees. (17) The method according to Embodiment 13, wherein screwing the threaded distal end of the locking shaft of the stem insertion device into the threaded hole formed in the femoral stem component includes rotating a knob fixed to the locking shaft to rotate the threaded distal end of the locking shaft and insert it into the threaded hole in the femoral stem component. (18) The method according to embodiment 13, further comprising inserting an auxiliary extraction plate extending inward away from the distal end of the grip of the stem insertion instrument in order to extract the femoral stem component from the intramedullary canal of the femur of the patient.

Claims

1. An orthopedic instrument for implanting a femoral stem component during a direct anterior approach orthopedic hip replacement surgery on the patient's femur, It is equipped with a stem insertion device, and the stem insertion device is An impact plate defining the proximal end of the aforementioned stem insertion device, A grip extending from the distal end of the impact plate, wherein (i) the longitudinal axis of the grip extends through the center of the impact plate, and (ii) the grip has an outer surface configured to grip the impact plate during insertion, A long, slender body extending from the distal end of the aforementioned grip, A locking mechanism captured within the elongated body, comprising: (i) a knob rotatable relative to the elongated body; and (ii) a locking shaft fixed to the distal surface of the knob and extending through the elongated body, wherein the threaded distal end of the locking shaft extends outward through an opening formed in the distal end of the elongated body, and the threaded distal end of the locking shaft is configured to be screwed into and received in a threaded hole formed in the femoral stem component; An orthopedic instrument wherein the longitudinal axis of the grip and the longitudinal axis of the locking shaft define an offset angle of 10 to 30 degrees.

2. The orthopedic instrument according to claim 1, wherein the offset angle defined by the longitudinal axis of the grip and the longitudinal axis of the locking shaft is 10 to 20 degrees.

3. The orthopedic instrument according to claim 1, wherein the offset angle defined by the longitudinal axis of the grip and the longitudinal axis of the locking shaft is approximately 12 degrees.

4. The aforementioned stem insertion device further comprises an auxiliary extraction plate, The auxiliary extraction plate extends inward away from the proximal end of the elongated body, The orthopedic instrument according to claim 1, wherein the auxiliary extraction plate has an extraction surface facing the distal end of the elongated body, which is configured to be inserted during the extraction of the femoral stem component.

5. The orthopedic instrument according to claim 1, wherein the rotation of the knob causes the locking shaft to rotate, thereby selectively screwing the threaded distal end of the locking shaft into the threaded hole of the femoral stem component when the threaded distal end of the locking shaft is positioned within the threaded hole of the femoral stem component.

6. When the threaded distal end of the locking shaft is positioned within the threaded hole of the femoral stem component, rotating the knob in the first direction causes the threaded distal end of the locking shaft to screw into the threaded hole of the femoral stem component. The orthopedic instrument according to claim 5, wherein rotation of the knob in the direction opposite to the first direction causes the threaded distal end of the locking shaft to disengage from the threaded hole of the femoral stem component, thereby allowing the locking shaft to be removed therefrom.

7. An orthopedic system for use in orthopedic hip replacement surgery with a direct anterior approach to the femur of a patient, An implantable femoral stem component configured to be implanted in a surgically prepared intramedullary canal of the femur of the patient, comprising: (i) a longitudinal axis extending upward / downward through the femoral stem component; and (ii) an elongated threaded hole having an upper end that opens to the upper surface of the femoral stem component; A stem insertion device comprising: (i) an impact plate defining the proximal end of the stem insertion device; (ii) a grip extending from the distal end of the impact plate, wherein (a) the longitudinal axis of the grip extends through the center of the impact plate, and (b) the grip has an outer surface configured to grip the shaft during insertion of the impact plate; (iii) an elongated body extending from the distal end of the grip; and (iv) a locking mechanism captured within the elongated body, comprising (a) a knob rotatable relative to the elongated body, and (b) a locking shaft fixed to the distal surface of the knob, wherein the threaded distal end of the locking shaft extends outward through an opening formed in the distal end of the elongated body and enters the threaded hole of the femoral stem component; An orthopedic system in which, when the threaded distal end of the locking shaft of the stem insertion device is positioned within the threaded hole of the femoral stem component, (i) the longitudinal axis of the grip and the longitudinal axis of the locking shaft define an offset angle of 10 to 30 degrees, and (ii) the longitudinal axis of the grip is aligned with the longitudinal axis of the femoral stem component.

8. The orthopedic system according to claim 7, wherein when the threaded distal end of the locking shaft of the stem insertion device is positioned within the threaded hole of the femoral stem component, the offset angle defined by the longitudinal axis of the grip and the longitudinal axis of the locking shaft is 10 to 20 degrees.

9. The orthopedic system according to claim 7, wherein when the threaded distal end of the locking shaft of the stem insertion device is positioned within the threaded hole of the femoral stem component, the offset angle defined by the longitudinal axis of the grip and the longitudinal axis of the locking shaft is approximately 12 degrees.

10. The orthopedic system according to claim 7, wherein when the threaded distal end of the locking shaft of the stem insertion device is positioned within the threaded hole of the femoral stem component, the longitudinal axis of the locking shaft is aligned with the longitudinal axis of the threaded hole of the femoral stem component.

11. When the threaded distal end of the locking shaft is positioned within the threaded hole of the femoral stem component, rotating the knob in the first direction causes the threaded distal end of the locking shaft to screw into the threaded hole of the femoral stem component. The orthopedic system according to claim 7, wherein rotation of the knob in the direction opposite to the first direction causes the threaded distal end of the locking shaft to disengage from the threaded hole of the femoral stem component, thereby allowing the locking shaft to be removed therefrom.

12. The aforementioned stem insertion device further comprises an auxiliary extraction plate, The auxiliary extraction plate extends inward away from the proximal end of the elongated body, The auxiliary extraction plate has an extraction surface that faces the femoral stem component when the threaded distal end of the locking shaft of the stem insertion device is positioned within the threaded hole of the femoral stem component. The orthopedic system according to claim 7, wherein the extraction surface is configured to be fitted during the extraction of the femoral stem component.

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