Femoral rear reference size measuring device

Abstract

An orthopedic instrument (10) for knee arthroplasty, the instrument comprising: a base (12) having one or more paddle plates configured for resting against and referencing one or both of a medial condyle and a lateral condyle of a femur; a body (14) coupled to the base for rotation relative to the base, where the body includes a recess and a notch therein and a first indicia (24) along a first face of the body adjacent to the notch; a post (20) received in the recess and movable relative to the body wherein the post has a second indicia (28) for use with the first indicia to determine a posterior dimension of the femur; and an adjustment mechanism (18) having a third marker (30) to indicate rotation of the femur, where the adjustment mechanism is configured to rotate the body to a desired orientation relative to the base based on rotation of the femur.

Description

[0001] Priority claim

[0002] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 351,619, filed on June 13, 2022, priority of which is hereby claimed and which is incorporated herein by reference in its entirety. Technical Field

[0003] The present disclosure relates to knee replacement surgery. More specifically, the present disclosure relates to an instrument for use during a knee replacement surgery procedure. Background Art

[0004] In a total knee replacement (TKA), the patient's distal femur is resected and replaced with a prosthetic femoral implant, and the patient's proximal tibia is resected and replaced with a prosthetic tibial implant. The prosthetic femoral implant articulates with the prosthetic tibial implant to restore joint motion.

[0005] Many factors affect joint motion after TKA surgery. The size and shape of each prosthetic implant will affect joint motion. To this end, the size of the femoral implant is carefully determined, and the anterior-posterior (AP) sizer is used to determine the anterior-posterior dimension of the resected distal femur. In addition, the position and orientation of each prosthetic implant determined by the position and orientation of the corresponding bone resection will affect joint motion. Summary of the invention

[0006] The present patent application provides an exemplary instrument for TKA femoral anterior-posterior (AP) sizing. The instrument can also measure the rotation of the femur to set the rotation of the femoral implant to ensure the alignment of the femoral implant with the patient's anatomical structure. The instrument can be used before resection or otherwise manipulating the patient's knee joint to assess the size and alignment of the femur. The instrument can be used to assist in planning a TKA operation, which includes drilling to position one or more resection guides used to resect the femur.

[0007] In some TKA surgeries, determining the size of the femur and setting the femoral rotation can be complicated. Most TKA surgeries use different instruments for the right knee in contrast to the left knee. In addition, one instrument may be used to determine the size of the femur, while another instrument may be used to determine the rotation of the femur. Therefore, at least two sizers and sometimes other instruments are included in the instrument system. Having additional instruments increases the cost and complexity of the surgery.

[0008] The inventors have recognized that the complexity of TKA surgery for measuring the size of the femur, measuring and setting the rotation can be reduced by providing a single instrument that can measure the anterior-posterior dimension of the femur and measure and set the rotation. In addition, the instrument will be universal and can be used for both the right knee joint and the left knee joint. The inventors have also recognized that the instrument can be used to guide one or more drill bits to drill holes in the femur. The instrument can eliminate the need for a dedicated guide (e.g., a gap reference drill guide). Therefore, the instrument can provide one or more bore holes, for example, which can be used to install a cutting guide. In this way, the number of surgical components can be reduced using the instrument disclosed herein.

[0009] To further illustrate the knee replacement apparatus disclosed herein, a non-limiting list of examples is provided herein. These examples are referred to as aspects and techniques.

[0010] In certain aspects, the technology described herein relates to an orthopedic device for knee replacement surgery, which may optionally include: a base having one or more paddles configured to rest against and reference one or both of the medial and lateral condyles of a femur; a body connected to the base for rotation relative to the base, wherein the body includes a recess and a notch therein and a first marking along a first surface of the body adjacent to the notch; a post received in the recess and movable relative to the body, wherein the post has a second marking that is used with the first marking to determine a posterior size of the femur; and an adjustment mechanism having a third marking to indicate rotation of the femur, wherein the adjustment mechanism is configured to rotate the body relative to the base to a desired orientation based on the rotation of the femur.

[0011] In some aspects, the technology described herein relates to an instrument, which may optionally include multiple retaining mechanisms, each retaining mechanism including a ball and spring assembly, wherein the multiple retaining mechanisms are located between various components, including at least between the base and the body, between the column and the body, and between the column and the stylus.

[0012] In certain aspects, the technology described herein relates to an instrument wherein, optionally, the adjustment mechanism includes a dial with a handle designed for manual adjustment of the dial by a surgeon.

[0013] In some aspects, the technology described herein relates to an instrument wherein, optionally, the column comprises an assembly comprising an outer sleeve, an inner shaft, and a cap, wherein the outer sleeve translates relative to the body but is rotationally fixed relative to the body, but the inner shaft is configured for rotation relative to the outer sleeve and the body.

[0014] In some aspects, the technology described herein relates to an instrument that may also optionally include a stylus coupled to a post via a cap and movable relative to the post, wherein the cap includes a hole for receiving a ball and the stylus includes a plurality of detents, each detent being configured to be engaged by the ball.

[0015] In some aspects, the technology described herein relates to an instrument wherein, optionally, the cap includes one or more grooves and one or more protrusions, and the stylus includes one or more lateral protrusions, each lateral protrusion being configured to be received in one of the one or more grooves.

[0016] In certain aspects, the technology described herein relates to an instrument wherein the inner shaft is optionally configured as a spring for retaining engagement with a ball, wherein the ball is biased against the stylus by the spring.

[0017] In some aspects, the technology described herein relates to an instrument wherein, optionally, the outer sleeve is rotationally fixed relative to the body by a protrusion defining a second indicia, wherein the protrusion is captured in a notch.

[0018] In some aspects, the technology described herein relates to an instrument wherein, optionally, the body includes a plurality of guide holes located therein and the base includes a second plurality of guide holes located therein.

[0019] In certain aspects, the technology described herein relates to an instrument wherein, optionally, a base includes a recess, a pawl, and a notch, wherein the adjustment mechanism is a dial rotatably inserted in the recess and configured to selectively engage the pawl with the ratchet, and the notch is configured to receive an arm that connects the base to the body.

[0020] In certain aspects, the technology described herein relates to an instrument in which an arm is selectively engaged by a dial and can travel within an arcuate groove in the dial.

[0021] In certain aspects, the technology described herein relates to an instrument in which the body is optionally rotatable relative to the base up to eighteen degrees (inclusive) via an adjustment mechanism.

[0022] In certain aspects, the technology described herein relates to an orthopedic instrument for knee replacement surgery, which may optionally include: a base having one or more paddles configured to rest against and reference one or both of the medial and lateral condyles of a femur; a body connected to the base for rotation relative to the base, wherein the body includes a recess and a notch located therein and a first marking along a first surface of the body adjacent to the notch; a post assembly received in the recess and movable relative to the body, wherein the post assembly includes an outer sleeve, an inner shaft, and a cap, the outer sleeve translates relative to the body but is fixed relative to the body in rotation, but the inner shaft is configured for rotation relative to the outer sleeve and the body, and wherein the post has a second marking that is used with the first marking to determine the posterior size of the femur; and a stylus connected to the post via the cap and movable relative to the post.

[0023] In certain aspects, the technology described herein relates to an instrument wherein, optionally, the cap includes a hole to receive a ball, and the stylus includes a plurality of detents, each detent being configured to be engaged by the ball.

[0024] In some aspects, the technology described herein relates to an instrument wherein, optionally, the cap includes one or more grooves and one or more protrusions, and the stylus includes one or more lateral protrusions, each lateral protrusion being configured to be received in one of the one or more grooves.

[0025] In some aspects, the technology described herein relates to an instrument wherein optionally, the inner shaft is configured as a spring for retaining engagement with a ball, wherein the ball is biased against the stylus by the spring.

[0026] In some aspects, the technology described herein relates to an instrument wherein, optionally, the outer sleeve is rotationally fixed relative to the body by a protrusion defining a second indicia, wherein the protrusion is captured in a notch.

[0027] In certain aspects, the technology described herein relates to an instrument that may optionally include: an adjustment mechanism having a third mark to indicate rotation of the femur, wherein the adjustment mechanism is configured to rotate the body relative to the base to a desired orientation based on the rotation of the femur; and a plurality of retaining mechanisms, each retaining mechanism comprising a ball and spring assembly, the plurality of retaining mechanisms being located between the various components, the plurality of retaining mechanisms being located between the various components including at least between the base and the body and between the post assembly and the body.

[0028] In certain aspects, the technology described herein relates to an orthopedic device for knee replacement surgery, which may optionally include: a base having one or more paddles configured to rest against and reference one or both of the medial condyle and the lateral condyle of a femur; a body connected to the base for rotation relative to the base, wherein the body includes a recess and a slot therein and a first marking along a first surface of the body adjacent to the slot; a post received in the recess and movable relative to the body, wherein the post has a second marking that is used with the first marking to determine a posterior size of the femur; a stylus connected to the post and movable relative to the post; an adjustment mechanism having a third marking to indicate rotation of the femur, wherein the adjustment mechanism is configured to rotate the body relative to the base to a desired orientation based on rotation of the femur; and a ball and spring assembly configured to hold the stylus together with the post.

[0029] In some aspects, the technology described herein relates to an instrument wherein, optionally, the post includes a cap having a hole for receiving a ball, wherein the stylus includes a plurality of detents, each detent being configured to engage with the ball, wherein the cap includes one or more grooves and one or more protrusions, and wherein the stylus includes one or more lateral protrusions, each lateral protrusion being configured to be received in one of the one or more grooves.

[0030] The above aspects may be combined in any one or any combination and / or may be optionally configured such that all elements or options described may be used or selected therefrom.

[0031] These and other examples and features of the present device will be partially described in the following detailed description. This summary is intended to provide an overview of the subject matter of this patent application. It is not intended to provide an exclusive or exhaustive removal of the present invention. The detailed description is included to provide further information about this patent application. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In the drawings, like numerals may be used to describe similar elements throughout the several views.The drawings illustrate primarily by way of example and not by way of limitation the various examples discussed in this document.

[0033] Figure 1 is a perspective view of a knee replacement instrument according to an example of the present disclosure.

[0034] Figure 1A According to the example of the present disclosure Figure 1 Exploded view of the device.

[0035] Figure 2AAccording to the example of the present disclosure Figure 1 A top plan view of the stylus of the instrument.

[0036] Figure 2B According to the example of the present disclosure Figure 2A A side plan view of a stylus.

[0037] Figure 2C According to the example of the present disclosure Figure 2A and Figure 2B A bottom plan view of the stylus.

[0038] Figure 3 According to the example of the present disclosure Figure 1 A plan view of the front of the apparatus.

[0039] Figure 3A According to the example of the present disclosure Figure 3 A perspective view of the rear portion of the instrument.

[0040] Figure 3B According to the example of the present disclosure Figure 3 A plan view of the side of the instrument.

[0041] Figure 3C According to the example of the present disclosure Figure 3 A first cross-sectional view of the device.

[0042] Figure 3D According to the example of the present disclosure Figure 3 A second cross-sectional view of the device.

[0043] Figure 3E According to the example of the present disclosure Figure 3 A third cross-sectional view of the device.

[0044] Figure 4 According to the example of the present disclosure Figure 1 A plan view of the front of the body of the apparatus.

[0045] Figure 4A According to the example of the present disclosure Figure 4 A cross-sectional view of the subject.

[0046] Figure 5 According to the example of the present disclosure Figure 1 A perspective view of the base of the apparatus.

[0047] Figure 5A According to the example of the present disclosure Figure 5 A plan view of the front of the base.

[0048] Figure 5B According to the example of the present disclosure Figure 5AA first cross-sectional view of a base.

[0049] Figure 5C According to the example of the present disclosure Figure 5 A second cross-sectional view of the base.

[0050] Figure 5D yes Figure 5C An enlarged view of a portion of the second cross-sectional view.

[0051] Fig. 6A and Figure 6B According to the example of the present disclosure Figure 1 A plan view of the side of the connecting rod of the apparatus.

[0052] Fig. 7A According to the example of the present disclosure Figure 1 A perspective view of a knob of an instrument.

[0053] Figure 7B According to the example of the present disclosure Fig. 7A A plan view of the rear of the knob.

[0054] Figure 8 is an example of an operation being performed to determine the size of a femur according to the present disclosure Figure 1 Perspective view of the instrument.

[0055] Fig. 9 According to the example of the present disclosure Figure 1 A perspective view of an instrument being operated to set the rotation of subsequent components using the femur as a reference.

[0056] Fig.10 According to the example of the present disclosure Figure 1 A perspective view of an instrument being operated to act as a drill guide having one or more hole guiding drill bits. DETAILED DESCRIPTION

[0057] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. Exemplary embodiments are provided so that the present disclosure will be comprehensive and its scope will be fully conveyed to those skilled in the art. Many specific details (such as examples of specific components, devices and methods) are set forth to provide a comprehensive understanding of the embodiments of the present disclosure. It will be appreciated by those skilled in the art that specific details need not be adopted, and exemplary embodiments may be embodied in many different forms, and none of them should be construed as limiting the scope of the present disclosure. In some exemplary embodiments, known processes, known device structures and known technologies are not described in detail.

[0058] As used herein, "proximal" refers to the direction generally toward the patient's head, and "distal" refers to the opposite direction of proximal, that is, the direction away from the patient's head. As used herein, the terms "front" and "rear" should be given their commonly understood anatomical explanations. Therefore, "rear" refers to the rear of the patient, for example, the rear of the knee. Similarly, "front" refers to the front of the patient, for example, the front of the knee. Therefore, "rear" refers to the opposite direction of "front". Similarly, the terms "inside" and "outside" should also be given their commonly understood anatomical explanations. "Inside" refers to the inside of the knee prosthesis (when in implant orientation), and "outside" refers to the outside. "Inside" refers to the opposite direction of "outside". "Varus" is defined as being related to or synonymous with "inside", or being relatively more medially arranged than the midline or other features or components. "Valgus" is defined as being related to or synonymous with "outside", or being relatively more medially arranged than the midline or other features or components.

[0059] As used herein, the term "varus-valgus" refers to varus to valgus or valgus to varus. Likewise, the terms "proximal-distal," "medial-lateral," and "anterior-posterior" refer to possible directions of reference for each term. Thus, for example, "proximal-distal" or "anterior / posterior" means "proximal to distal" or "distal to proximal."

[0060] Reference Figure 1 , an instrument 10 is shown. The instrument 10 can be configured for anterior-posterior (AP) sizing of the femur, can measure the rotation of the femur, and can set the rotation of the femoral implant to ensure that the femoral implant is aligned with the patient's anatomy.

[0061] The instrument 10 may include a base 12 , a body 14 , a linkage assembly 16 , an adjustment mechanism 18 , a post assembly 20 , and a stylus 22 .

[0062] The base 12 may be coupled to the body 14 via a linkage assembly 16. The body 14 may be movable relative to the base 12 via the linkage assembly 16. The base 12 may be configured to receive an adjustment mechanism 18. The adjustment mechanism 18 may be coupled to the base 12 and may additionally be coupled to the linkage assembly 16. The adjustment mechanism 18 may be movable relative to the base 12 and may drive movement of the linkage assembly 16, as further described herein.

[0063] The body 14 can be configured to receive the linkage assembly 16 and the column assembly 20. The column assembly 20 can be coupled with a stylus 22. The stylus 22 can be movable relative to the column assembly 20 and the body 14. The column assembly 20 can be movable relative to the body 14 (e.g., in a semi-constrained manner), as further discussed herein.

[0064] The device 10 can be configured for use on the left or right knee of the patient. In addition, the device 10 can measure the rotation of the knee joint (left or right), such as the measured orientation up to 9 degrees relative to the neutral position. For example, the measured rotation (angle) can indicate the varus / valgus angle of the patient's knee joint and / or the internal / external rotation of the patient's knee joint.

[0065] The adjustment mechanism 18 can be adjusted throughout an 18 degree range of motion (9 degrees varus and 9 degrees valgus). The adjustment mechanism 18 can have an indication of the femoral Figure 1 A first mark 24 is provided on the body 14 for rotating along the axis A in the body. A second mark 28 may be provided on the body 14 to measure and indicate the appropriate posterior size of a femoral implant (not shown). The second mark 28 may be used in combination with the third mark 30 on the column assembly 20. The stylus 22 may include a fourth mark 32 to measure and indicate the appropriate anterior size of a femoral implant (not shown). Using the second mark 28, the third mark 30 and the fourth mark 32, the instrument 10 may measure the anterior-posterior distance from the posterior condyle of the femur (in contact with the base 12) (see subsequent drawings) to the anterior cortex of the femur. The anterior cortex may serve as a reference for the tip of the stylus 22. This information (anteroposterior distance) may be used to select the profile size of the femoral implant. The profile size may be indicated using one or more of the marks 28, 30 and / or 32 of the instrument 10.

[0066] Figure 1A yes Figure 1 An exploded view of the device 10 is shown in FIG. 1 , wherein the stylus 22 is removed. Thus, Figure 1A The base 12, the body 14, the linkage assembly 16, the adjustment mechanism 18 and the column assembly 20 are shown. The base 12 may include a paddle 36 ( Figure 1A ), dial recess 38, and flange 40. In addition to second marker 28, body 14 may include recess 42 and drill guide hole 44. Link assembly 16 may include fastener 46, arm 48, and second fastener 50. In addition to first marker 24, adjustment mechanism 18 may include fastener 52 and dial 54. Post assembly 20 may include third marker 30, outer sleeve 60, inner shaft 62, and cap 64. Figure 1A Additional spring and ball assemblies of the instrument 10 are shown and will be discussed in greater detail later.

[0067] Paddle 36( Figure 1AThe base 12 may include a first face 38 of the base 12 that is located on a side of the base 12 that is opposite the paddle 36. The base 12 may include a first face 38 of the base 12 that is located on a side of the base 12 that is opposite the paddle 36. The base 12 may include a second face 38 of the base 12 that is located on a side of the base 12 that is opposite the paddle 36. The base 12 may include a second face 38 of the base 12 that is located on a side of the base 12 that is opposite the paddle 36. The base 12 may include a second face 38 of the base 12 that is located on a side of the base 12 that is adjacent to the paddle 36 but is proximal to the paddle 36.

[0068] The body 14 can have an inverted T-shape with wings extending laterally from a trunk or center portion. A recess 42 can be located in the trunk and can be configured to receive at least a portion of the post assembly 20. The recess 42 can include one or more openings, as further described herein, including a notch along a first side of the body 14. A drill guide hole 44 can be located in the wings of the body 14 and can extend through the body 14 from the first side of the body 14 to the femoral-facing side of the body 14.

[0069] The fastener 46 can couple the arm 48 to the body 14. However, the fastener 46 can allow the arm 48 to pivot relative to the body 14. The arm 48 can extend from a first end (coupled to the fastener 46) to a second end that interfaces with and movably engages with the adjustment mechanism 18. In particular, the arm 48 can be configured as a follower of the adjustment mechanism 18, as further described and shown. A second fastener 50 can be received in a hole in the flange 40 of the base 12 and can extend therethrough to be threaded or otherwise fastened to the femoral-facing side of the body 14. The fastener 50 can be configured to allow the body 14 to pivot relative to the base 12, as further described and shown herein.

[0070] The fastener 52 of the adjustment mechanism 18 can hold the dial 54 in place in a rotatable manner relative to the base 12. As previously described, the dial 54 can selectively rotate up to 9 degrees (including the end points) clockwise and up to 9 degrees (including the end points) counterclockwise relative to the base 12 on the fastener 52. Therefore, the dial 54 can rotate up to 18 degrees (including the end points) on the fastener 52.

[0071] The outer sleeve 60 may have a first hole 66 at or near the distal end, which is configured to receive a fastener 67 (e.g., a pin, a screw, etc.) forming the third mark 30. The outer sleeve 60 may include a second hole 68 at or near the proximal end, which is configured to receive the inner shaft 62. The outer sleeve 60 may be linearly movable in the proximal-distal direction relative to the body 14, but when the fastener 67 is captured in the notch of the body 14, the outer sleeve 60 may not be rotatable relative to the body 14. The inner shaft 62 may be rotatable within the outer sleeve 60. Therefore, the inner shaft 62 may be rotatable relative to the outer sleeve 60 and the body 14. The inner shaft 62 may be retained in the outer sleeve 60 by a fastener 70, which is at least partially received in a channel 72 or a necking region of the inner shaft 62 except the hole of the outer sleeve 60. The cap 64 may be coupled downwardly to the proximal end of the inner shaft 62 and / or above. The cap 64 may be configured to receive the contact pin 22 ( Figure 1A ), and allows the stylus 22 to be movable in a non-proximal direction (eg, forward and backward).

[0072] Figure 1A A spring and ball assembly (also referred to herein as a "retaining mechanism") that can be used with the instrument 10 is shown. The retaining mechanism 73 can be used to reduce undesirable slop or play between components. In some cases, the retaining mechanism 73 can also facilitate a desired amount of engagement between the components (e.g., the retaining mechanism 73 can maintain the relative position of the components when the components are not being handled / manipulated by the surgeon). The first ball 74 and the first spring 76 can engage the outer sleeve 60 from a position mounted within the body 14. At least the second ball 78A, 78B and the second spring 80A, 80B can engage the body 14 from a position mounted within the base 12. The third ball 82 and the third spring 84 can be mounted in the inner shaft 62 and / or the cap 64, and the third ball 84 can pass through a hole in the cap 64 to engage the stylus 22 ( Figure 1A not shown) joined.

[0073] Figures 2A-2C The contact pin 22 is shown in more detail. Figure 2A , the stylus 22 may include a tip portion 84, a curved portion 86, a body 88, and a front end portion 90. The body 88 may include the fourth marking 32, lateral protrusions 92A and 92B, and a retaining feature 94 (only Figure 2C shown).

[0074] The stylus 22 may or may not be connected to the rest of the instrument 10 ( Figure 1 and Figure 1A) for use with the stylus 22. The use of the stylus 22 can be determined by the surgeon. The stylus 22 can have a slender and relatively thin flat shape. The body 88 can extend along the longitudinal axis LA. The curved portion 86 can be connected to the body 88 (e.g., in an integral manner) and can extend along the longitudinal axis, but can also extend in a second direction (e.g., distally) to the tip portion 84. The tip portion 84 can be connected to the curved portion 86. The tip portion 84 can be configured via the curved portion 86 and the body 88 to be used as a reference to an anatomical point on the femur (e.g., the anterior cortex of the femur).

[0075] The front end portion 90 can be connected to the body 88 (e.g., in an integral manner). The front end portion 90 can include a necked or reduced material area to facilitate manipulation by the surgeon. Lateral protrusions 92A and 92B can extend to the front end portion 90. The lateral protrusions 92A and 92B can extend longitudinally from the front end portion 90 to the curved portion 86 along the length of the body 88. The lateral protrusions 92A and 92B form a reduced thickness area relative to the thickness of the rest of the body 88. The lateral protrusions 92A and 92B are configured to mate with mating features (e.g., grooves and / or protrusions on the proximal side of the cap 64) to facilitate manipulation by the surgeon. Figure 1 and Figure 1A The features of cap 64 in combination with lateral projections 92A and 92B may retain stylus 22 on cap 64 but may allow stylus 22 to selectively move along longitudinal axis LA. Thus, once stylus 22 is coupled to cap 64, stylus 22 may be movable only along longitudinal axis LA.

[0076] The fourth mark 32 may be located on the first surface 96 (eg, the top surface) of the body 88. The fourth mark 32 may be based on the contact pin 22 from the cap 64 ( Figure 1 and Figure 1A ) extends to the distance of the anterior cortex or other features on the femur as a reference for the profile size of the femoral implant. The fourth mark 32 may include a line and / or a number that can be aligned with a corresponding line (mark) on the cap 64.

[0077] The stylus 22 may have a second surface 98. The second surface 98 may be opposite the first surface 96. The retention feature 94 may be formed in the body 88 and may extend into the second surface 98 so as to have an opening at the second surface 98. The retention feature 94 may include a detent or other feature configured to receive the third ball 82 ( Figure 1A ) extending from the cap 64. For example, the retaining features 94 can have a position along the longitudinal axis LA corresponding to the fourth markings 32. Therefore, each retaining feature 94 can have a longitudinal position corresponding to one of the fourth markings 32.

[0078] The third spring 84 ( Figure 1A ) A retaining force may be applied on the stylus 22 via the third ball 82. While applying this force, the stylus 22 may be captured and held by the generally opposing forces of the grooves and protrusions using the lateral protrusions 92A and 92B.

[0079] Figure 3-3E Various side views of the device 10 are shown. Figure 3 A first side 100 is shown (the anterior portion when the instrument 10 is mounted to the femur). The components of the instrument 10 have been previously referenced. Figure 1 and Figure 1A A discussion was held.

[0080] Figure 3A A second side 102 is shown (the posterior portion when the instrument 10 is mounted to the femur). Figure 3A The structure of the cap 64 is shown in greater detail. In particular, the third ball 82 is captured in a recess 104 in the cap 64. The recess 104 may extend into a first surface 106 in the cap 64. As previously described, the third ball 82 may extend from the first surface 106 to engage the stylus 22.

[0081] The cap 64 may include arms 108A and 108B. The arms 108A and 108B may extend from the first surface 106. The arms 108A and 108B may include grooves 110A and 110B, protrusions 112A and 112B, and fifth markings 114A and 114B.

[0082] The recesses 110A and 110B may be sized to receive the lateral projections 92A and 92B ( Figures 2A-2C ). The protrusions 112A and 112B can extend back toward each other to form a restriction or capture structure at the proximal side of the cap 64. The protrusions 112A and 112B can be formed by multiple portions of the stylus 22 ( Figures 2A-2C ) are engaged, for example, with multiple parts of the main body 88 ( Figures 2A-2C ) engagement. As previously described, the protrusions 112A and 112B can be engaged by the stylus 22 and capture the stylus 22. As previously described, the third ball 82 pressed against the stylus 22 facilitates such engagement. The fifth markings 114A and 114B (e.g., lines) can be located on the proximal side of the protrusions 112A and 112B, respectively. As previously described, the fifth markings 114A and 114B can interact with the fourth marking 32 of the stylus 22.

[0083] Figure 3A Also shown is a recess 116 in the body 14. The recess 116 is configured to receive the flange 40 therein. The recess 116 and the flange 40 may be shaped to allow pivotal movement of the body 14 relative to the base 12 on the second fastener 50.

[0084] Figure 3B A side view of the instrument 10 is shown. Figure 3C Shown along Figure 3 Cross-sectional view of line CC. Figure 3C The base 12, the body 14, the linkage assembly 16, the adjustment mechanism 18 and the column assembly 20 are shown. As previously mentioned, the base 12 may include a paddle 36 ( Figure 3C 4. The column assembly 20 may include a third marker 32 (part of the fastener 67, which may simply be a mark, line, etc.), an outer sleeve 60, an inner shaft 62, and a cap 64. Figure 3C Also shown are the first ball 74 and first spring 76 and the third ball 82 and third spring 84 .

[0085] Figure 3D Shown along Figure 3 A second cross-section of line DD. Figure 3D The view of FIG. 1 shows a portion of the body 14 and the base 12, and also shows the second ball 78A and the second spring 80A. The second ball 78A can be pressed against the base 12 (e.g., the flange 40) by the second spring 80A. The engagement of the second ball 78A (and the second ball 78B not shown) can reduce unnecessary play or sloshing between the base 12 and the body 14.

[0086] Figure 3E Shown along Figure 3 A third cross section of line EE. Figure 3E A portion of the body 14 is shown along with the fastener 46 and a portion of the arm 48 of the linkage assembly 16 .

[0087] Figure 4 and Figure 4A The main body 14 and the column assembly 20 are shown, wherein the column assembly 20 is relative to Figure 3C The position in the shift. Figure 4 In addition to the second marking 28 , the recess 42 , and the drill guide hole 44 , the body 14 may include wings 118A and 118B, second drill guide holes 120A and 120B, a stem 122 , and a notch 124 .

[0088] Wing 118A may define one of the drill guide hole 44 and the second drill guide hole 120A. The second drill guide hole 120A may be offset by a desired amount (e.g., 2 mm) relative to the drill guide hole 44. Wing 118A may extend laterally from the trunk 122. Similarly, wing 118B may define one of the drill guide hole 44 and the second drill guide hole 120B. The second drill guide hole 120B may be offset by a desired amount (e.g., 2 mm) relative to the corresponding drill guide hole 44. Wing 118B may extend laterally from the trunk 122.

[0089] The trunk 122 may have a proximal-distal elongated shape and may have the second marking 28 on a first face thereof. The trunk 122 may define a recess 42 therein. A notch 124 may extend from the first face to communicate with the recess 42.

[0090] like Figure 4 and Figure 4A As shown, the third marker 30 (a portion of the fastener 67) can be retained in the notch 124. The third marker 30 can include a protrusion 126 (e.g., a head or other feature of the fastener 67) captured by the notch 124. This arrangement of the captured protrusion 126 can limit the outer sleeve 60 ( Figure 4A ) but may allow limited translation of the outer sleeve 60 relative to the body 14 (as indicated by the length of the slot 124).

[0091] Figure 5-5D Other features of the base 12 are shown. As previously described, these features may include paddles 36 (only Figure 5 ), the dial recess 38 and the flange 40. Now refer to Figure 5A The base 12 may further include one or more drill guide holes 128A and 128B, a slot 130 , and a first hole 132 and a second hole 134 .

[0092] The first of the drill guide holes 128A can be positioned adjacent to the first of the paddles 36, and the second of the drill guide holes 128B can be positioned adjacent to the second of the paddles 36. The drill guide holes 128A and 128B are optional and may not be used by some surgeons to secure the base 12 to the femur. The notch 130 can extend from its proximal side into the dial recess 38. The notch 130 can be configured to receive at least a portion of the arm 48 ( Figure 1A ). The first hole 132 can be located within the dial recess 38, such as at the center thereof. The first hole 132 can be configured to be threadedly connected to or otherwise receive a distal portion of the fastener 52 ( Figure 1A The second hole 134 can be located in the flange 40 and can be configured to receive the second fastener 50 therein ( Figure 1A ).

[0093] Figure 5B Shown along Figure 5A The cross section of line BB. Figure 5C A cross section through a portion of the dial recess 38 is shown. Figure 5D yes Figure 5C An enlarged view of a portion of the dial recess 38 .

[0094] Figure 5B The dial recess 38, the flange 40, the first hole 132 and the second hole 134 are shown. Figures 5B-5D As shown in FIG. 1 , a protrusion or detent 136 may be located within the dial recess 38 so as to protrude from a side 138 of the base 12 that forms the dial recess 38. Although Figures 5B-5D A single detent 136 is shown in FIG, but multiple detents or other engagement features may be used in other examples. Figure 5D As best shown in , the pawl 136 may be an arm having a tapered or inclined ramp surface 140 and a peak 142 adjacent to the ramp surface 140 .

[0095] Fig. 6A and Figure 6B Various aspects of the arm 48 are shown. Fig. 6A As shown, arm 48 can have an elongated length with a body 144, a first end 146, and a second end 148. First end 146 can be opposite second end 148. First end 146 can include a hole 150. Second end 148 can include a pin 152. Hole 150 can be configured to receive fastener 46 ( Figure 1A The pin 152 may be configured to be received in a channel or groove 154 ( Fig. 7A ). The groove 154 may have an arcuate or curved shape, and may include, for example, a cam groove.

[0096] Fig. 7A and Figure 7B A dial 54 is shown. Fig. 7A As shown in FIG. 1 , the dial 54 includes a first mark 24 along a surface 155. The dial 54 may include a handle portion 156 ( Fig. 7A ), the handle portion 156 has a hole 158 ( Figure 7B ), the hole 158 is configured to receive the fastener 52 ( Figure 1A ). The dial 54 may also include a ratchet 160 having a detent 161 along a second side 162 thereof.

[0097] The shape of the detent 161 can be designed to engage with the pawl 136 ( Figure 5D ) of the slope surface 140 and the peak 142 ( Figure 5D) interaction. The engagement of the pawl 136 with the catch 161 can hold the dial 54 relative to the base 12 ( Figure 1A ), unless selectively rotated by the surgeon. Fig. 6A and Figure 6B ) (and particularly the pin 152) and the channel or groove 154 can cause the body 14 ( Figure 1A ) pivots with the pivoting of the dial 54. When the pin 152 ( Fig. 6A and Figure 6B ) reaches one of the ends of the channel or groove 154, the pin 152 and the channel or groove 54 can also limit the rotation of the dial 54. For example, the limit to the rotation of the dial 54 can be about 9 degrees (including the end points) clockwise and about 9 degrees (including the end points) counterclockwise from the neutral position.

[0098] Figure 8 The instrument 10 is shown mounted to the distal portion 200 of the femur 202. As previously described, the instrument 10 is in the process of measuring the proximal-distal dimension of the femur 202 using the post assembly 20 and the stylus 22. Briefly, the base 12 can be positioned for use via the paddle 36 ( Figure 8 only one is shown) contacts the anterior and posterior condyles 206 ( Figure 8 Only one condyle is shown). The post assembly 20 can be moved relative to the body 14 to an appropriate posterior reference height. The stylus 22 can be moved relative to the body 14 and the post assembly 20 so as to be referenced to a second portion of the femur 202 (e.g., by being referenced to an anatomical feature (e.g., anterior cortex)). The markings discussed above (second, third, fourth, fifth, etc.) can be used to measure the anterior-posterior dimensions of a femoral implant and select an appropriate profile size for the femoral implant.

[0099] Fig. 9 The instrument 10 is shown mounted to the distal portion 200 of the femur 202 and in the process of measuring the rotation of the femur 202. In particular, the adjustment mechanism 18 can be rotated clockwise relative to the base 12 to rotate the body 14 relative to the base 12 and the femur 202 via the linkage mechanism 16. The rotation of the femur 202 and the body 14 is indicated using the first marking 24 on the dial 54. Fig. 9 The rotation to 9 degrees shown in is purely exemplary and is illustrated to illustrate the rotational capability of the instrument 10 to measure rotation of the femur 202 for installation of implants, guides, etc. The rotation of the femur is determined by visual alignment with the Whiteside line, which extends from the center of the intercondylar notch to the deepest point of the trochlear groove.

[0100] Fig.10The instrument 10 is shown mounted to the distal portion 200 of the femur 202 and in the process of using one of the drill guide holes 44 and the drill guide hole 128B. Once the proximal-distal size and rotation of the femur 202 have been determined, one of the drill guide holes 44 and the drill guide hole 128B can be used. In particular, the drill guide hole 128B can be used to guide the first tool 208 (e.g., a drill, pin, fastener, etc.) into the femur 202. Once placed, the drill, pin, fastener, etc. can be removed or can be used to help install the base 12 to the femur 202. A similar process can be repeated using the drill guide hole 128A.

[0101] A second tool 210 (e.g., a drill) can be guided by one of the drill guide holes 44 of the body 14 to form a recess in the femur 202. The recess can be used to mount a cutting guide or other instrument (e.g., via bone screws, pins, fasteners, etc.) to perform a resection or other surgical technique on the femur 202. The process of using the second tool 210 can be repeated using a second one of the drill guide holes 44 to guide drilling on a second side of the body 14.

[0102] Alternatively, the instrument 10 may include a set of modular accessories that are not specifically shown. The instrument 10 and the accessories may be provided together as a system. In this way, a surgeon or another user may select a first accessory from the system and attach or use the first accessory with the instrument 10. As the surgical procedure proceeds, the surgeon may select a second accessory from the system and attach or use the second accessory with the instrument 10 or with the first accessory. Therefore, in some examples, when the second accessory is attached, the first accessory may be left in place. Various different coupling mechanisms (e.g., dovetail joints) and locking mechanisms (e.g., keys, ball detents) may be used to selectively receive and retain the desired modular accessories on the instrument 10. More information about modular accessories for the instrument 10 may be found in U.S. Pat. No. 10,166,034B2, entitled "Knee Arthroplasty Instrument" to Claypool et al., the disclosure of which is incorporated herein by reference in its entirety.

[0103] Unless otherwise indicated, the components described herein may be unitary (i.e., a single-part structure) or may be coupled together in a known manner (e.g., using mechanical mechanisms known in the art, such as interference fits, coupling features such as threads, mating elements, etc.).

[0104] The above detailed description includes the description of the accompanying drawings, which form a part of the detailed description. The accompanying drawings show specific examples in which the present invention can be put into practice by way of illustration. These examples are also referred to as "examples" in this article. These examples may include elements other than the elements shown or described. However, the inventors have also contemplated examples that only provide the elements shown or described. In addition, the inventors have also contemplated examples of any combination or permutation of those elements (or one or more aspects thereof) shown or described in relation to a specific example (or one or more aspects thereof) or other examples (or one or more aspects thereof) shown or described herein.

[0105] In the event of an inconsistency in usage between this document and any document incorporated by reference, the usage in this document controls.

[0106] In this document, as is common in patent documents, the terms "a" or "an" include one or more, independent of any other instance or use of "at least one" or "one or more".

[0107] In this document, the term "or" is used to refer to a non-exclusive or, such that "A or B" includes "A but not B," "B but not A," and "A and B," unless otherwise noted. In this document, the terms "including" and "in which" are used as the plain English equivalents of the respective terms "comprising" and "wherein." Furthermore, in the following claims, the terms "including" and "comprising" are open-ended, i.e., systems, devices, articles, compositions, formulations, or methods that include elements other than the elements listed after the term in a claim are still deemed to fall within the scope of the claim. Furthermore, in the following claims, the terms "first," "second," and "third," etc. are used merely as labels and are not intended to impose numerical requirements on their objects.

[0108] The above description is intended to be illustrative rather than restrictive. For example, the above examples (or one or more aspects thereof) may be used in combination with each other. For example, those skilled in the art may use other examples after reading the above description. The abstract is provided to comply with the provisions of Section 1.72 (b) of Chapter 37 of the Code of Federal Regulations of the United States, so that readers can quickly determine the nature of the technical disclosure. The premise of submitting this document is that this document will not be used to interpret or limit the scope or meaning of the claims. In addition, in the above detailed description, various features can be combined together to simplify the present disclosure. This should not be interpreted as meaning that the disclosed features that are not claimed for protection are essential to any claim. On the contrary, the subject matter of the present invention may be less than all the features of the specific disclosed examples. Therefore, the attached claims are incorporated into the detailed description as examples or instances, each claim exists alone as a separate example, and it is conceivable that these examples can be combined with each other in various combinations or arrangements. The scope of the present invention should be determined with reference to the attached claims and the full range of equivalents enjoyed by these claims.

Claims

1. An orthopedic device for knee replacement, the device comprising: a base having one or more paddles configured to rest against and reference one or both of the medial and lateral condyles of a femur; a body coupled to the base for rotation relative to the base, wherein the body includes a recess and a notch therein and a first marking along a first face of the body adjacent to the notch; a post received in the recess and movable relative to the body, wherein the post has a second marking for use with the first marking to determine a posterior dimension of the femur; and An adjustment mechanism has a third marking to indicate rotation of the femur, wherein the adjustment mechanism is configured to rotate the body relative to the base to a desired orientation based on the rotation of the femur.

2. The apparatus of claim 1, wherein: The instrument also includes a plurality of retaining mechanisms, each retaining mechanism including a ball and spring assembly, and the plurality of retaining mechanisms are located between various components, including at least between the base and the body, between the column and the body, and between the column and the stylus.

3. The apparatus according to any one of claims 1 to 2, wherein: The adjustment mechanism includes a dial having a handle configured for manual adjustment of the dial by a surgeon.

4. The apparatus according to any one of claims 1 to 3, wherein: The post includes an assembly including an outer sleeve that translates relative to the body but is rotationally fixed relative to the body, an inner shaft configured for rotation relative to the outer sleeve and the body, and a cap.

5. The apparatus of claim 4, wherein: The instrument also includes a stylus coupled to the post by the cap and movable relative to the post, the cap including a hole to receive the ball, and the stylus including a plurality of detents, each detent being configured for engagement by the ball.

6. The apparatus of claim 5, wherein: The cap includes one or more grooves and one or more protrusions, and the contact pin includes one or more lateral protrusions, each lateral protrusion being configured to be received in one of the one or more grooves.

7. The apparatus according to any one of claims 5 to 6, wherein: The inner shaft is configured as a spring for retaining engagement with the ball, the ball being biased against the stylus by the spring.

8. The apparatus of any one of claims 4 to 7, wherein: The outer sleeve is rotationally fixed relative to the body by a projection defining the second indicia, the projection being captured in the notch.

9. The apparatus of any one of claims 1 to 8, wherein: The body includes a plurality of guide holes therein, and the base includes a plurality of second guide holes therein.

10. The apparatus of any one of claims 1 to 9, wherein: The base includes a recess, a pawl, and a notch, the adjustment mechanism is a dial rotatably inserted in the recess and configured to selectively engage the pawl with the ratchet, and the notch is configured to receive an arm connecting the base to the body.

11. The apparatus of claim 10, wherein: The arm is engaged by the dial and is capable of traveling within an arcuate slot in the dial.

12. The apparatus of any one of claims 1 to 11, wherein: The main body can be rotated relative to the base by eighteen degrees, including eighteen degrees, via the adjustment mechanism.

13. An orthopedic device for knee replacement, the device comprising: a base having one or more paddles configured to rest against and reference one or both of the medial and lateral condyles of a femur; a body coupled to the base for rotation relative to the base, wherein the body includes a recess and a notch therein and a first marking along a first face of the body adjacent to the notch; a post assembly received in the recess and movable relative to the body, wherein the post assembly includes an outer sleeve, an inner shaft, and a cap, the outer sleeve translating relative to the body but being rotationally fixed relative to the body, but the inner shaft being configured for rotation relative to the outer sleeve and the body, and the post having a second marking for use with the first marking to determine the posterior size of the femur; and A stylus is coupled to the post via the cap and is movable relative to the post.

14. The apparatus of claim 13, wherein: The cap includes a hole to receive a ball, and the stylus includes a plurality of detents, each detent being configured to be engaged by the ball.

15. The apparatus of claim 14, wherein: The cap includes one or more grooves and one or more protrusions, and the contact pin includes one or more lateral protrusions, each lateral protrusion being configured to be received in one of the one or more grooves.

16. The apparatus of any one of claims 14-15, wherein: The inner shaft is configured as a spring for retaining engagement with the ball, the ball being biased against the stylus by the spring.

17. The apparatus of any one of claims 13 to 16, wherein: The outer sleeve is rotationally fixed relative to the body by a projection defining the second indicia, the projection being captured in the notch.

18. The apparatus of any one of claims 13 to 17, wherein: The apparatus further comprises: an adjustment mechanism having a third marking to indicate rotation of the femur, wherein the adjustment mechanism is configured to rotate the body relative to the base to a desired orientation based on the rotation of the femur; and A plurality of retaining mechanisms, each retaining mechanism comprising a ball and spring assembly, wherein the plurality of retaining mechanisms are located between various components, including at least between the base and the body and between the column assembly and the body.

19. An orthopedic device for knee replacement, the device comprising: a base having one or more paddles configured to rest against and reference one or both of the medial and lateral condyles of a femur; a body coupled to the base for rotation relative to the base, wherein the body includes a recess and a notch therein and a first marking along a first face of the body adjacent to the notch; a post received in the recess and movable relative to the body, wherein the post has a second marking for use with the first marking to determine a posterior dimension of the femur; a stylus coupled to the post and movable relative to the post; an adjustment mechanism having a third marking to indicate rotation of the femur, wherein the adjustment mechanism is configured to rotate the body relative to the base to a desired orientation based on the rotation of the femur; and A ball and spring assembly is configured to retain the stylus with the post.

20. The apparatus of claim 19, wherein: The post includes a cap having a hole for receiving the ball, the contact pin includes a plurality of detents, each detent is configured to be engaged by the ball, the cap includes one or more grooves and one or more protrusions, and the contact pin includes one or more lateral protrusions, each lateral protrusion is configured to be received in one of the one or more grooves.

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