Femoral offset system for knee arthroplasty procedure

Abstract

To provide a femoral offset system that allows comfortable handling, thereby simplifying a workflow in using the femoral offset system in a knee arthroplasty procedure.SOLUTION: A femoral offset system 14 includes: a femur component connectable to a distal portion of a femur; and a femoral offset instrument connectable to the femur component. The femoral offset instrument includes a femur support 16 adapted to connect to the femur component via a connection mechanism.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to a femoral offset system including a femoral offset instrument and to such a femoral offset instrument for use in knee arthroplasty, particularly revision knee arthroplasty. [Background technology]

[0002] Femoral offset instruments make it possible to determine and / or measure and / or verify the femoral offset of a femoral implant on the distal part of the femur. Such instruments are known from the prior art. Summary of the Invention [Problem to be solved by the invention]

[0003] It is an object of the present disclosure to provide a femoral offset system that allows for comfortable handling, thus simplifying the workflow when using the femoral offset system in knee arthroplasty. [Means for solving the problem]

[0004] A first aspect relates to a femoral offset system for use in knee arthroplasty, particularly revision knee arthroplasty. The femoral offset system comprises a femoral component connectable to a distal part of the femur and a femoral offset instrument connectable to the femoral component. The femoral offset instrument comprises a femoral support, which is adapted to be connected to the femoral component via a connection mechanism. A connection mechanism for connecting the femoral offset instrument to the femoral component comprises a fixed peg and a movable peg connected to the femoral offset instrument, a manually operable operating element capable of retracting the movable peg by applying a manual force against a tensile force, and receiving pockets for the fixed peg and the movable peg arranged on the femoral component. To connect the femoral offset instrument to the femoral component, the movable peg is retracted by applying a manual force against a tensile force, the femoral offset instrument and the femoral component are aligned with each other accordingly, the manual force is released, and the movable peg is snapped into the corresponding receiving pocket by the applied tensile force.

[0005] This connection mechanism allows for a fixed, static, non-rotatable, non-displaceable, yet releasable connection of the femoral offset instrument to the femoral component.

[0006] The proposed solution only requires manually pushing in the operating element, thereby retracting the movable peg by applying a manual force against the pulling force, and releasing the operating element. In particular, the proposed solution avoids the use of screws or other connection methods which require more effort.

[0007] According to one embodiment, the fixed peg and the movable peg of the femoral offset instrument are disposed on the femoral support medially and laterally with respect to the marking element, the fixed peg being fixedly connected to the femoral support, and the movable peg being movably disposed on the femoral support.

[0008] Advantageously, the movable peg and the operating element are fixedly connected. The movable peg and the operating element may be fixedly connected via a rigid bond or any other suitable connection method. The movable peg and the manually operable operating element may be realized as an integral component.

[0009] In some exemplary embodiments, the femoral support includes at least one guide groove, the operating element includes a corresponding protrusion disposed in said guide groove, and the femoral support and the operating element are adapted such that the protrusion can slide within the guide groove. When the operating element is operated by applying or releasing a manual force, the operating element moves translationally in the respective direction guided by the guide groove.

[0010] The two guide grooves and the two protrusions may be disposed distally and proximally relative to one another, respectively.

[0011] Advantageously, the operating element is held in the femoral support, for example via a suitable holding mechanism. Despite this holding, the operating element and the femoral support can move relative to each other within a defined range. The holding can be via one or two pins arranged in corresponding recesses in the femoral support, which prevent the projection from slipping out of the guide groove.

[0012] According to a further preferred embodiment, the femoral support comprises at least one femoral attachment member for fixedly connecting the femoral support to the femoral component, and the femoral component comprises at least one corresponding recess for receiving one of the femoral attachment members, e.g., the femoral attachment member extends medially or laterally from the femoral support.

[0013] Advantageously, the femoral support comprises two femoral attachment members, the two femoral attachment members being arranged medially and laterally with respect to the marking element, the fixing peg being fixedly connected to one of the attachment members and the other of the attachment members receiving the operating element. For example, the medially arranged femoral attachment member extends medially from the femoral support. For example, the lateral arranged femoral attachment member extends laterally from the femoral support. If the fixing peg is fixedly connected to the medially arranged femoral attachment member, the fixing peg extends medially therefrom. If the fixing peg is fixedly connected to the lateral arranged femoral attachment member, the fixing peg extends laterally therefrom.

[0014] When the externally disposed mounting member receives the operating element, a pulling force acts in an outward direction, and when no manual force is applied against the pulling force, the movable peg connected to the operating element extends outward from the externally disposed mounting member.

[0015] When the inwardly disposed mounting member receives the operating element, a pulling force acts in an inward direction, and when no manual force is applied against the pulling force, the movable peg connected to the operating element extends inwardly from the inwardly disposed mounting member.

[0016] The femoral component may include two corresponding recesses for receiving the two femoral attachment members, the recesses being disposed medially and laterally relative to one another, and receiving pockets for receiving the fixed pin and the mobile pin extending in the medial and lateral directions, respectively, from the recesses.

[0017] According to one embodiment, the femoral component is a trial femoral implant and / or a femoral cutting guide. The femoral component, in particular the trial femoral implant or the femoral cutting guide, is temporarily connectable during a knee arthroplasty procedure.

[0018] According to one embodiment, the marking element is an offset eyeballing. This marking element allows for visual estimation of the femoral offset. In combination with the offset bushing, the marking element allows for the femoral offset to be determined and / or measured and / or verified. The offset bushing is a separate part that can be connected to a femoral offset instrument. The offset bushing, held by the femoral support, is rotatable about an axis of rotation. According to a further embodiment, the marking element and the offset bushing may allow for guiding a drill to prepare the femoral cone using the drill.

[0019] A second aspect of the present disclosure relates to a femoral offset instrument for a femoral offset system according to the described embodiments, the femoral offset instrument comprising a femoral support adapted to be connected to a femoral component via a connection mechanism comprising a fixed peg and a movable peg connected to the femoral offset instrument, and a manually operable operating element allowing for retraction of the movable peg by application of manual force against a pulling force.

[0020] According to a further embodiment, the femoral offset instrument may be designed as described above with respect to the femoral offset system.

[0021] A third aspect of the present disclosure relates to a femoral component for a femoral offset system according to the described embodiments, the femoral component being connectable to a distal portion of the femur and including receiving pockets for fixed and movable pegs of a femoral offset instrument.

[0022] According to a further embodiment, the femoral component may be designed as described above with respect to the femoral offset system.

[0023] A fourth aspect of the present disclosure relates to a set of femoral offset systems and / or femoral offset instruments and / or femoral components comprising at least two femoral offset systems according to a described embodiment and / or at least two femoral components according to a described embodiment and / or at least two femoral components according to a described embodiment, wherein the at least two femoral offset systems and / or the at least two femoral components and / or the two femoral components differ at least in size or shape.

[0024] Further advantageous embodiments can be derived from the following description of exemplary embodiments with reference to the drawings, in which: [Brief description of the drawings]

[0025] [Figure 1] Schematic showing the femoral offset instrument in different views a) and b) and c). [Diagram 2] Schematic diagram of a portion of the femoral offset instrument in different views a) and b). [Diagram 3] 2A and 2B are schematic views showing a femoral component according to an embodiment from different perspectives a) and b). [Figure 4] 1A and 1B are schematic diagrams showing a femoral offset system according to an embodiment in different views a) and b). [Diagram 5] 13A and 13B are schematic views of a femoral component according to another embodiment, showing different views a) and b). [Figure 6] 13A and 13B are schematic diagrams illustrating a femoral offset system according to another embodiment; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] Figure 1 illustrates a schematic of a femoral offset instrument 10. The femoral offset instrument 10 may be used in a femoral offset system 14, such as depicted in Figures 4 and 6, with a femoral component 12, such as depicted in Figures 3 and 5.

[0027] The femoral offset system 14 is designed for use in knee arthroplasty, particularly revision knee arthroplasty.

[0028] The femoral offset instrument 10 is a right- or left-only instrument with respect to a right or left femur. This means that the femoral offset instrument 10 has a right or left orientation, as indicated, for example, by an "R" or "L" marked on the instrument. In the following examples, a left-only instrument is described.

[0029] The distal, proximal, medial, and lateral directions for the left femur are indicated by arrows D / P, M / L, respectively.

[0030] The femoral component 12 is temporarily connectable to a distal portion of a femur (not shown).

[0031] The femoral offset instrument 10 is connectable to the femoral component 12 via a connection mechanism (see, for example, FIGS. 4 and 6). The connection mechanism allows the femoral offset instrument 10 to be fixedly, statically, non-rotatably and non-displaceably, but releasably, connected to the femoral component 12. The design and function are exemplarily described below with reference to the figures.

[0032] The femoral offset instrument 10 comprises a femoral support 16. The femoral support 16 is adapted to be connected to the femoral component 12 via a connection mechanism. According to an embodiment, the femoral offset instrument 10 comprises a marking element 18 that provides a marking of the offset.

[0033] Figure 1a) shows the femoral offset instrument 10 in an exploded view in an unloaded state, while Figures 1b) and c) show the femoral offset instrument 10 in a loaded state.

[0034] In the illustrative embodiment, the femoral bearing 16 includes two femoral attachment members 20 for fixedly connecting the femoral bearing 16 to the femoral component 12. A medial disposed femoral attachment member 20M extends medially from the femoral bearing 16. A lateral disposed femoral attachment member 20L extends laterally from the femoral bearing 16.

[0035] Each mounting member 20 may have a flat end 44 combined with two rounded ends 46, which allows for easier positioning of the mounting members 20 and improved accuracy in positioning.

[0036] The femoral offset instrument 10 includes a fixed peg 22 and a movable peg 24, both of which are connected to the femoral offset instrument 10. The fixed peg 22 is fixedly connected to the femoral support 16. In the illustrated embodiment, the fixed peg 22 is connected to a medially disposed femoral attachment member 20M. The movable peg 24 is movably disposed on the femoral support 16.

[0037] The fixing peg 22 may have a flat end 48 combined with two rounded ends 50, which allows for easier positioning of the fixing peg 22 and improved accuracy during positioning.

[0038] In the embodiment, the movable peg 24 is fixedly connected to an operating element 26 of the femoral offset instrument 10. According to the embodiment, the movable peg 24 and the operating element 26 are realized as an integral component. In the embodiment, the externally disposed femoral attachment member 20L receives the operating element 26.

[0039] Thus, the fixed peg 22 and the movable peg 24 of the femoral offset instrument 10 are positioned on the femoral support 16 medial and lateral to the marking element 18 .

[0040] The operating element 26 is manually operable, and the movable peg 24 can be retracted by applying a manual force against the pulling force. In the embodiment, the pulling force is provided by a spring 30. According to the embodiment, the pulling force acts in an outward direction. The movable peg connected to the operating element 26 extends outward from the outwardly arranged mounting member 20L (see FIG. 1 ) in the absence of a manual force against the pulling force. The movable peg can be retracted in an inward direction by applying a manual force against the pulling force on the operating element 26.

[0041] In the embodiment, the femoral support 16 comprises two guide grooves 32. The operating element 26 comprises two corresponding protrusions 34, one of which is formed by the movable peg 24. The protrusions 34 are arranged in the respective guide grooves 32, and the femoral support 16 and the operating element 26 are adapted so that the protrusions 34 can slide in the guide grooves 32. When operating the operating element 26 by applying or releasing a manual force, the operating element moves translationally in the respective direction guided by the guide grooves 32. In the embodiment, the two guide grooves 32 and the two protrusions 34 are arranged distally and proximally relative to each other.

[0042] In this embodiment, the operating element 26 is held on the femoral support 16, for example via a suitable holding mechanism. Despite this holding, the operating element 26 and the femoral support 16 can move relative to each other within a predetermined range. The holding is performed via two pins 36 arranged in corresponding recesses 38 of the femoral support 16, which prevent the projections 34 from falling out of the guide grooves 32.

[0043] With respect to the femoral component 12, the connection mechanism comprises two recesses 40 disposed on the femoral component 12 for receiving corresponding femoral attachment members 20. The recesses 40M, 40L are disposed medially and laterally relative to each other.

[0044] The femoral component 12 further includes two receiving pockets 42 for the fixation peg 22 and the mobile peg 24. The receiving pocket 42M for receiving the fixation pin 22 extends in a medial direction from the medially disposed recess 40M, and the receiving pocket 42L for receiving the mobile pin 24 extends in a lateral direction from the laterally disposed recess 40L.

[0045] To connect the femoral offset instrument to the femoral component, the following procedure may be performed.

[0046] The femoral offset instrument and femoral component are positioned relative to one another by placing the inboard mounted mounting member 20M within the inboard recess 40M such that the fixation peg 22 engages the receiving pocket 42M.

[0047] The movable peg 24 is retracted by applying manual pressure to the operating element 26 against the pulling force such that the movable peg 24 retracts in an inward direction.

[0048] The femoral offset instrument 10 and femoral component 12 are aligned with one another by positioning the outboard mounting member 20L within the recess 40L, the manual pressure is released, and the movable peg 24 is snapped outwardly into the corresponding receiving pocket 42L by the applied pulling force.

[0049] The proposed solution only requires manually pushing in the operating element 26, thereby retracting the movable peg 24 by applying a manual force against the pulling force, and releasing the operating element 26. In particular, the proposed solution avoids the use of screws or other connection methods which require more effort.

[0050] According to one embodiment, the femoral component is a trial femoral implant (see Figures 3 and 4).

[0051] According to a further embodiment, the femoral component is a femoral cutting guide (see Figures 5 and 6).

[0052] According to an embodiment, the marking element 18 is an offset eyeballing that allows for visual estimation of the femoral offset. During knee arthroplasty, the offset eyeballing helps the surgeon to determine the femoral offset to be used for positioning the implant. In combination with an offset bushing, not shown in the figures, the marking element 18 allows for determining and / or measuring and / or verifying the correct femoral offset. The offset bushing is a separate part that can be connected to a femoral offset instrument. The offset bushing held by the femoral support 16 is rotatable about an axis of rotation. According to a further embodiment, the marking element 18 and the offset bushing may allow for guiding a drill to prepare the femoral cone using the drill.

Claims

1. A femoral offset system (14) for use in knee arthroplasty, particularly revision knee arthroplasty, comprising: a femoral component (12) connectable to a distal portion of a femur; and a femoral offset instrument (10) connectable to the femoral component (12); The femoral offset instrument (10) comprises a femoral support portion (16); the femoral support (16) is adapted to be connected to the femoral component (12) via a connection mechanism; The connection mechanism includes: A femoral offset system (14) comprising: a fixed peg (22) and a movable peg (24) connected to the femoral offset instrument (10); a manually operable operating element (26) capable of retracting the movable peg (24) by applying a manual force against a tensile force; and receiving pockets (42, 42M, 42L) disposed on the femoral component (12) for the fixed peg (22) and the movable peg (24).

2. 2. The femoral offset system (14) of claim 1, wherein the fixed peg (22) and the movable peg (24) of the femoral offset instrument (10) are positioned on the femoral support (16) medially and laterally relative to a marking element (18) of the femoral offset instrument (10).

3. 2. The femoral offset system (14) according to claim 1, wherein the movable peg (24) and the operating element (26) are fixedly connected, in particular the movable peg (24) and the operating element (26) are realised as an integral component.

4. 2. The femoral offset system of claim 1, wherein the femoral support portion includes at least one guide groove, the operating element includes a corresponding protrusion disposed within the guide groove, and the femoral support portion and the operating element are adapted such that the protrusion is adapted to slide within the guide groove.

5. The femoral offset system (14) of claim 4, wherein the movable peg (24) defines a protrusion (34) disposed within the guide channel (32).

6. The femoral offset system (14) of claim 1 , wherein the manipulative element (26) is carried by the femoral support (16).

7. 2. The femoral offset system of claim 1, wherein the femoral support (16) comprises at least one femoral attachment member (20) for fixedly connecting the femoral support (16) to the femoral component (12), the femoral component (12) comprising at least one corresponding recess (40) for receiving one of the femoral attachment members (20).

8. 3. The femoral offset system of claim 2, wherein the femoral support portion (16) comprises two femoral mounting members (20, 20M, 20L) arranged medially and laterally with respect to the marking element (18), the fixation peg (22) being fixedly connected to one of the mounting members (20M) and the other of the mounting members (20L) receiving the operating element (26).

9. 9. The femoral offset system of claim 8, wherein the femoral component (12) comprises two corresponding recesses (40, 40M, 40L) for receiving the two femoral attachment members (20, 20M, 20L), the recesses (40, 40M, 40L) being disposed medially and laterally with respect to one another, and the receiving pockets (42, 42M, 42L) for receiving the fixed peg (22) and the mobile peg (24) extending in a medial and lateral direction, respectively, from the recesses (40, 40M, 40L).

10. The femoral offset system (14) of claim 1, wherein the femoral component (12) is a trial femoral implant and / or a femoral cutting guide.

11. The femoral offset system (14) of claim 2, wherein the marking element (18) is an offset eyepiece.

12. 12. A femoral offset instrument (10) for a femoral offset system (14) according to any one of claims 1 to 11, said femoral offset instrument (10) comprising a femoral support (16), said femoral support (16) adapted to be connected to said femoral component (12) via a connection mechanism, The connection mechanism includes: A femoral offset instrument (10) comprising a fixed peg (22) and a movable peg (24) connected to the femoral offset instrument (10), and a manually operable operating element (26) capable of retracting the movable peg (22) by applying manual force against a pulling force.

13. 12. A femoral component (12) for a femoral offset system (14) according to any one of claims 1 to 11, said femoral component (12) being connectable to a distal portion of a femur and comprising receiving pockets (42, 42M, 42L) for fixed and movable pegs (22) and (24) of a femoral offset instrument (10).

14. 12. A set of femoral offset systems (14), comprising at least two femoral offset systems (14) according to any one of claims 1 to 11, wherein the at least two femoral offset systems (14) differ in at least one size or shape.

15. A set of femoral offset instruments (10), comprising at least two femoral offset instruments (10) as described in claim 12, wherein at least two of the femoral offset instruments (10) differ in at least size or shape.

16. A set of femoral components (12), comprising at least two femoral components (12) as described in claim 13, wherein at least two of the femoral components (12) differ in at least size or shape.

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