Device for orthopedic implant

Abstract

The present application relates to a device for defining a bone cavity. The device includes a connection member, a reamer, and a guide member. The connecting member includes at least one rotatable connecting mechanism for connecting the guide member and the reamer. The reamer and the guiding component are connected to the two opposite ends of the connecting component respectively. The reamer is arranged to rotate about a pivot of the guide member. The guide member serves as a pivot point. The guide member includes a head and a tail. The tail portion of the guide member is connected to an implant.

Description

TECHNICAL FIELD

[0001] The present application relates to a device for orthopedic implants. More particularly, the present application discloses a device for reaming a cavity around an orthopedic implant. BACKGROUND

[0002] Patients with deteriorated hip joints are subjected to hip replacement surgery. In hip replacement surgery, the hip joint is replaced in whole or in part by an artificial implant.

[0003] Normally, a hip joint comprises a femur (thigh bone) which is connected to the pelvis by a ball and socket joint. In hip replacement surgery, a stem prosthesis (or implant) is implanted into the femur to strengthen the hip joint. A conventional stem prosthesis comprises a stem portion which extends axially and a neck portion which is disposed at an angle to the stem portion. The stem prosthesis is inserted into a cavity in the femur, with the neck portion indirectly connecting the stem portion to the pelvis.

[0004] In about 30% of cases, an undesirable gap between the proximal portion of the stem prosthesis and the femur is observed after the stem prosthesis is inserted, resulting in a lack of support for the proximal portion of the stem prosthesis. If the gap is not addressed, it can lead to implant failure and / or femoral fracture.

[0005] Conventional devices are complex in structure and provide limited support to the surrounding area of the implanted prosthesis in the bone cavity.

[0006] Therefore, there is a need for a system which can provide sufficient support to the surrounding area of the implanted stem prosthesis to limit the gap between the implant and the bone, while being simple in structure and easy to use. SUMMARY

[0007] Particular embodiments of the present application will be described herein below with reference to the drawings, it being understood that the disclosed embodiments are merely examples, and that the present application can be embodied in various forms. In order not to obscure the present application with details that are well known in the art, well-known functions or constructions are not described in detail. Therefore, the specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for the claims and as an aid to understanding the application of the present application in various appropriate detailed structures.

[0008] The present application relates to a device for defining a bone cavity, the device comprising a guide member, a reamer and a connecting member. The tail portion of the guide member is configured to be inserted into at least one groove of an implant. The opposite ends of the connecting member are configured to be provided with the guide member and the reamer, respectively. The reamer is configured to rotate around the pivot point of the guide member. The guide member acts as a pivot point. The guide member comprises a head portion and a tail portion. The tail portion of the guide member is configured to be connected to the implant.

[0009] The foregoing features and other features, and advantages of the present application will become more apparent from the following detailed description, taken in conjunction with the accompanying drawings, in which: BRIEF DESCRIPTION OF DRAWINGS

[0010] The above summary of the present application, as well as the following detailed description of exemplary embodiments of the present application, will be better understood in connection with the accompanying drawings, which are described in detail below.

[0011] Figure 1 A perspective view of the device 100 according to an embodiment of the present application is shown.

[0012] Figure 2 An exploded view of the device 100 according to an embodiment of the present application is shown.

[0013] Figure 3 A perspective view of the connecting member 110 of the device 100 according to an embodiment of the present application is shown.

[0014] Figure 4 A perspective view of the reamer 120 of the device 100 according to an embodiment of the present application is shown.

[0015] Figure 5 A perspective view of the guide member 130 of the device 100 according to an embodiment of the present application is shown.

[0016] Figure 6 A schematic view of the device 100 according to an embodiment of the present application coupled with an implant 300 implanted within a femur 200 is shown.

[0017] Figure 7 An exemplary flowchart 700 of operating the device 100 according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0018] Before one embodiment of the present application is described in detail, the following terminology will be defined: the terms "including" and "comprising" and variations thereof as used in this document mean "including, but not limited to"; the term "or" as used in this document is inclusive, meaning and / or; the phrases "coupled to" and "connected to" as used in this document mean including, being included within, interconnected to, containing, being contained within, connected to or with, communicable with, cooperating with, interleafed with, adjacent, bound to or with, having, having a property of, and / or the like; definitions for certain words and phrases are provided throughout this patent document, and one of ordinary skill in the art should understand that such definitions can apply to this document in many, if not most, instances in which such words and phrases are used.

[0019] The specification refers to "one embodiment" "an embodiment" or the like meaning that a particular feature, structure, or characteristic described is included in at least one embodiment. Thus, appearances of the phrases "in one embodiment", "in an embodiment", and similar phrases in various places throughout the specification are not necessarily all referring to the same embodiment, unless otherwise indicated. Enumerated items do not mean that any or all of the items are mutually exclusive and / or mutually inclusive, unless otherwise indicated. The terms "one", "a", and "the" do not exclude a plurality, unless otherwise indicated. Portions of the disclosure provided in terms of a program, software module, or other symbolically represented items, have a relationship to a machine operations and / or instructions for operation. References to such should not be construed as referencing a specific embodiment unless otherwise indicated.

[0020] Although the operations of the exemplary embodiments of the disclosed methods can be described in a particular, sequential order, it should be understood that the disclosed embodiments can encompass operations that are performed in different orders or concurrently. For example, operations described sequentially can in some cases be rearranged or performed concurrently. Moreover, the description and illustrations of the disclosed embodiments are not intended to be limiting. Other embodiments can be used and otherwise modified without departing from the spirit of the disclosure. Furthermore, for ease of explanation, the drawings can not show various ways the disclosed systems, methods, and devices can be used in combination with other systems, methods, and devices.

[0021] Furthermore, the described features, advantages, and characteristics of the embodiments can be combined in any manner. Those skilled in the relevant art will recognize that the embodiments can be practiced with one or more of the specific features or advantages of the embodiments separated into different embodiments. In other words, when a particular feature, advantage or characteristic is described in one embodiment, it can be incorporated into another embodiment to yield still a further embodiment that includes that particular feature, advantage or characteristic, but not other features of that one or more embodiments. These and other changes can be made to the embodiments in light of the above-detailed description. The detailed description is to be understood as including all technical equivalents of the elements described and illustrated.

[0022] In the context of the present application, the gap refers to the space between the bone and the implant after insertion of the implant. The term "cavity" refers to a reshaped or redefined gap in which a filler block is to be inserted. Typically, the size of the cavity corresponds to the size of the filler block.

[0023] The device of the present application is described in the context of a femoral implant in a hip surgery of a patient. However, it is envisaged that at least some embodiments of the present application can involve the use of the device in the context of a humeral implant in a shoulder surgery. In such embodiments, the structure of the device can be substantially as described below, although the overall size and shape of the device can be arranged to allow it to be operated in the humeral region rather than the femoral region. It is also envisaged that at least some embodiments of the present application can involve the use of the device in the context of a (distal) femoral implant or a tibial implant in a knee surgery.

[0024] The present application discloses a device for defining a cavity in a bone, the cavity corresponding to the size of a filler block to be inserted in the peri-implant cavity of an orthopedic implant (or implant).

[0025] Reference is now made to the drawings, Figure 1 An exemplary embodiment of the device 100 is shown, Figure 2 An exploded view of the device 100 is shown. The device 100 is configured to define a cavity in a femur around an implant, the cavity corresponding to the size of a filler block. Typically, the gap left in the femur after implant insertion can be uneven or vary in size due to individual differences. If the gap is not filled, it can lead to implant failure and / or femur fracture. Therefore, in order to reshape or re-size the gap according to the size of a filler block or other filling device to be placed in the femur 200, the device 100 is used. The device 100 is used to perform a milling operation in the exact area to reshape or re-size the gap, thereby defining a cavity in the femur 200.

[0026] The device 100 includes a proximal end 100a and a distal end 100b. The device 100 includes a connecting member 110, a reamer 120 and a guide member 130.

[0027] The connecting member 110 includes a first end 110a and a second end 110b. At least one end of the connecting member 110 includes at least one rotatable connecting mechanism. The rotatable connecting mechanism connects the connecting member 110 with the reamer 120 and / or the guide member 130. In one embodiment, both ends of the connecting member 110 are provided with the rotatable connecting mechanism, connecting with the reamer 120 and the guide member 130, respectively. The connecting member 110 can be of any suitable shape, such as a cuboid, a sphere, a cylinder, a trapezoid, etc. In one embodiment, the connecting member 110 is a rounded trapezoid. The connecting member 110 can be made of any suitable biocompatible material, such as titanium, cobalt-chromium alloy, stainless steel or any other metal alloy. In one embodiment, the connecting member 110 is made of 17-4PH stainless steel.

[0028] In the assembled exemplary embodiment of the connecting member 110, the reamer 120, and the guide member 130, the connecting member 110 is provided with holes. The connecting member 110 includes at least two holes. In one embodiment, the at least two holes include a first hole 111 and a second hole 112. The first hole 111 and the second hole 112 extend from a first face 113 to a second face (not shown) of the connecting member 110. The first hole 111 and the second hole 112 can be positioned at predetermined locations along the length of the connecting member 110. In one embodiment, the first hole 111 is disposed near a first end 110a of the connecting member 110 and the second hole 112 is disposed near a second end 110b of the connecting member 110. Thus, the first hole 111 and the second hole 112 are spaced apart by a predetermined distance for milling bone around a proximal portion of the implant stem. The predetermined distance varies depending on the diameter of the implant stem and the patient's bone anatomy.

[0029] The first hole 111 and the second hole 112 can have equal or different diameters. In one embodiment, the first hole 111 has a smaller diameter than the second hole 112. The first hole 111 has a diameter of at least 5 mm. The second hole 112 has a diameter of at least 5 mm. The inner surfaces of the first hole 111 and the second hole 112 can be smooth, threaded, or half-threaded. In one embodiment, the inner surfaces of the first hole 111 and the second hole 112 are smooth. Alternatively, the first hole 111 and the second hole 112 can be tapered.

[0030] In one exemplary embodiment, the connecting member 110 can include a length adjustment mechanism for adjusting the distance between the first hole 111 and the second hole 112. The length adjustment mechanism can provide the surgeon with length adjustment options during the surgery.

[0031] The first hole 111 of the connecting member 110 is configured to allow at least a portion of the reamer 120 to pass through. The second hole 112 of the connecting member 110 is configured to allow the guide member 130 to pass through.

[0032] In one embodiment, the first hole 111 or the second hole 112 or both include a rotation mechanism. For example, the first hole 111 includes the rotation mechanism to facilitate rotation of the reamer 120. The rotation mechanism includes, but is not limited to, a bushing, a bearing, or the like. As a result of the rotation mechanism, the reamer 120 is configured to be rotatably connected with the first hole 111 of the connecting member 110. In one embodiment, the reamer 120 and the first hole 111 are connected to the connecting member 110 via a bearing (not shown).

[0033] Alternatively, the first hole 111 and the second hole 112 can comprise other structures to facilitate the connection of the reamer 120 to the connecting member 110 and the connection of the guide member 130 to the connecting member 110. For example, the holes can comprise snap-fit slots or slot-fit slots configured to receive at least a portion of the reamer 120 or the guide member 130.

[0034] The reamer 120 can comprise, but is not limited to, a cylindrical reamer, a tapered reamer, an expanding reamer, an adjustable reamer, and the like. In one embodiment, the reamer 120 is a cylindrical reamer. The reamer 120 comprises an adapter 121, a shaft portion 122, and a blade portion 123. Figure 4 The adapter 121 is disposed at the top of the reamer 120, the blade portion 123 is disposed at the bottom of the reamer 120, and the shaft portion 122 is located between the adapter and the blade portion 123. The adapter 121, the shaft portion 122, and the blade portion 123 can form a unitary unit or comprise connecting mechanisms to assemble the reamer 120. In one embodiment, the reamer 120 is a unitary unit comprising the adapter 121, the shaft portion 122, and the blade portion 123. The reamer 120 can be made of any suitable biocompatible material, such as stainless steel, titanium, cobalt-chrome alloy, or any other metal alloy.

[0035] The shaft portion 122 is operatively connected to the rotation mechanism disposed within the first hole 111 of the connecting member 110. The connection enables the reamer 120 to rotate relative to the connecting member 110.

[0036] In one exemplary embodiment, the reamer 120 comprises a housing connected to the connecting member 110, the housing covering at least a portion of the reamer 120. In one embodiment, the housing covers the shaft portion 122 of the reamer 120. The housing comprises suitable connecting mechanisms such that the reamer 120 is free to rotate within the housing. The blade portion 123 of the reamer 120 extends from the housing to enable unrestricted reaming or milling operations.

[0037] The adapter 121 of the reamer 120 is connected to an external rotation mechanism, such as a power tool (not shown). The external rotation mechanism provides rotational power to the reamer 120. As the reamer 120 rotates, the connecting member 110 remains stationary due to the rotational connection between the first hole 111 and the reamer 120.

[0038] The diameter of the blade portion 123 can vary depending on the width of the cavity to be reamed. In one embodiment, the blade portion 123 is detachably connected to the stem portion 122. In reaming a femur, the blade portion 123 of the appropriate diameter can be connected. Alternatively, the blade portion 123 can have a uniform diameter or a tapered diameter.

[0039] The second aperture 112 of the connecting member 110 is connected to the guide member 130 by any suitable mechanism, such as a snap fit, a press fit, etc. In one embodiment, the guide member 130 and the connecting member 110 are connected by a press fit mechanism. The guide member 130 can be of any suitable shape. In one embodiment, the guide member 130 is cylindrical. The guide member 130 can be made of any suitable biocompatible material, such as stainless steel, titanium, cobalt-chrome alloy, or any other suitable metal alloy.

[0040] The guide member 130 includes a head portion 131 and a tail portion 132. In one embodiment, the guide member 130 is rotatably connected to the connecting member 110 by the second aperture 112. The second aperture 112 can include any suitable mechanism to facilitate rotational connection with the guide member 130. The mechanism includes, for example, a bearing, a bushing, etc. In one embodiment, the second aperture 112 includes a bearing (not shown). The second aperture 112 serves as a pivot point for the device 100 to rotate about the implant 300 within the cavity of the bone.

[0041] Further, the connecting member 110 can include a height adjustment mechanism, such that the connecting member 110 can be inserted to a desired height level on the implant 300. In one embodiment, the height adjustment mechanism includes a stopper 133. The stopper 133 can be disposed at any suitable position along the length of the connecting member 110. Figure 5 The stopper 133 prevents further movement of the connecting member 110 beyond a pre-set length.

[0042] At least a portion of the guide member 130 is disposed in connection with the implant 300. In one embodiment, the tail portion 132 of the guide member 130 is connected to the implant 300. Figure 6 The guide member 130 and the implant 300 can be connected by any suitable method, such as a snap fit, a press fit, a friction fit, fastening, a threaded mechanism, etc. In one embodiment, the guide member 130 and the implant 300 are connected by a threaded mechanism. In one embodiment, the tail portion 132 of the guide member 130 is disposed to be inserted into at least a portion of a recess of the implant 300. As shown in Figure 6 the guide member 130 is connected to the recess of the implant 300 implanted in the bone 200.

[0043] Figure 6 An assembled exemplary embodiment of the implant 300, femur 200 and the device 100 is shown. As shown, after the implant 300 is implanted, the device 100 is mounted on the implant 300 to ream a cavity corresponding to the size of the filler block to be inserted into the cavity. In one embodiment, the surgeon selects the appropriate size of the filler block according to the size of the femur. Alternatively, a standard size filler block can be used. Although Figure 6 One embodiment of the implant is shown, but the device of the present application can also be used with other known implants.

[0044] The tail 132 of the guide member 130 is inserted into at least a portion of the groove of the implant 300, while the reamer 120 is positioned outside and adjacent to the implant. The connecting member 110 supporting the tail 132 of the guide member 130 and the reamer 120 can be located on top of the implant 300. The method of reaming a cavity is described below Figure 7

[0045] Figure 7 A flow chart of the method of operation 700 of the device 100 to ream a cavity of a desired size according to one embodiment is shown. The device 100 is used to ream a bone, such as the femur 200.

[0046] In step 701, the device 100 is connected to the implant 300 when the surgeon finds a gap between the implant 100 and the femur 200 and deems it necessary. The surgeon places the tail 132 of the guide member 130 into the groove of the implant 300.

[0047] Step 702 is optionally performed by the surgeon, as the connecting member 110 can or can not include a length adjustment mechanism. After the device 100 is connected, the surgeon adjusts the length of the connecting member 110 so that the blade 123 of the reamer 120 is placed in the gap between the implant 300 and the femur 200. Initially, a smaller size reamer 120 can be selected so that it can be easily inserted into the gap between the implant 300 and the bone.

[0048] In step 703, the adapter 121 of the reamer 120 is connected to an external rotating mechanism, such as a power drill. The external rotating mechanism rotates the reamer 120 and the blade 123, thereby initiating the reaming action. The surgeon reshapes the gap in the femur 200 to form a cavity so that the cavity can be filled by inserting the filler block.

[0049] ​In step 704, the surgeon can insert at least one trial filler block into the cavity to check and select the appropriate trial filler block. The surgeon can repeat this step by inserting trial filler blocks of different thicknesses in sequence until the most appropriate trial filler block is selected. The filler block corresponding to the most appropriate trial filler block is then selected. By following the procedure and selecting the appropriate size of the filler block, the cavity can be adequately filled, ensuring the longevity of the implant 300. The thickness of the trial filler block can be between 5 mm and 10 mm, or as otherwise specified.

[0050] In step 705, the device 100 is detached from the implant 300 by loosening the fasteners (not shown). The appropriate filler block is then selected.

[0051] In step 706, the filler block is attached / inserted into the cavity. After the filler block is inserted, the surgeon attaches the filler block to the implant 300 via the fasteners.

[0052] Thus, the milling device brings great ease to a complex surgical procedure and aids in milling the cavity to the desired size, followed by the insertion of the filler block into the cavity to support the stem prosthesis.

[0053] The scope of the application is limited only by the claims that follow. More particularly, all parameters, dimensions, materials, and arrangements described herein are meant to be exemplary and that the actual parameters, dimensions, materials, and / or arrangements will depend upon the specific application or applications for which the teachings of the present application is / are used.

Claims

1. A device (100) for defining a bone cavity, characterized in that, Comprising: a. a connecting member (110) comprising at least one rotatable connecting mechanism disposed near at least one end of the connecting member (110); b. a reamer (120); and c. a guide member (130) comprising a head portion (131) and a tail portion (132), the guide member (130) serving as a pivot point, the tail portion (132) of the guide member (130) being disposed to connect with an implant (300); wherein the reamer (120) and the guide member (130) are connected at opposite ends of the connecting member (110), respectively; and wherein the reamer (120) is disposed to rotate about the pivot point of the guide member (130).

2. The apparatus (100) according to claim 1, characterized in that At least one of the connecting member (110), the reamer (120), and the guide member (130) is made of a biocompatible material.

3. The apparatus (100) according to claim 1, characterized in that The connecting member (110) comprises a first hole (111) and a second hole (112).

4. The apparatus (100) according to claim 3, characterized in that The first hole (111) and the second hole (112) comprise a rotating mechanism.

5. The apparatus (100) according to claim 4, characterized in that The rotating mechanism comprises one of a bushing or a bearing.

6. The apparatus (100) according to claim 3, characterized in that The first hole (111) and the second hole (112) comprise a slot fit or a snap fit slot.

7. The apparatus (100) according to claim 3, characterized in that An inner surface of the first hole (111) and the second hole (112) is one of a smooth surface, a threaded surface, or a half-threaded surface.

8. The apparatus (100) according to claim 3, characterized in that At least one of the first hole (111) and the second hole (112) is tapered.

9. The apparatus (100) according to claim 1, characterized in that The reamer (120) comprises: an adapter (121), a blade portion (123), and a stem portion (122) between the adapter (121) and the blade portion (123), the adapter (121) being connected with an external rotating mechanism to provide a rotating capability to the reamer (120).

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