Description:TECHNICAL FIELD
[1] The present disclosure relates to stem neck trial component. Moreover, the present disclosure relates to a method of assembly of the stem neck trial component.
BACKGROUND
[2] Hip replacement, or hip arthroplasty, is a well-established surgical procedure designed to relieve pain and restore functionality to patients suffering from joint degeneration, arthritis, or hip injuries. The hip joint consists of a ball-and-socket mechanism, where the ball (femoral head) at the top of the thigh bone (femur) fits into a socket in the pelvic bone. Over time, wear and tear or injury can damage these components, leading to pain, reduced mobility, and overall discomfort. Hip arthroplasty replaces these damaged parts with artificial implants, allowing patients to return to daily activities with improved mobility and reduced pain. While significant advances have been made in implant design, technical challenges remain in ensuring proper alignment, stability, and adaptation of the implant to the patient’s unique anatomy, which is critical for successful surgical outcomes.
[3] Existing solutions attempt to address this problem by offering modular trial systems, where surgeons use different neck or head sizes to achieve various offsets. However, these solutions come with their own drawbacks. First, the need for multiple components increases the risk of mismatch or misalignment during surgery, leading to suboptimal outcomes. Additionally, using separate necks or heads for different offsets can be time-consuming and cumbersome during the surgery. A requirement to swap out components mid-surgery also increases the chances of intraoperative errors and prolongs the overall procedure time, which can contribute to greater patient risk and longer recovery periods.
[4] Therefore, in light of the foregoing discussion, there exists a need to overcome the aforementioned drawbacks.

SUMMARY
[5] A primary objective of the present disclosure seeks to provide a stem neck trial component with an adjustable offset. Another primary objective of the present disclosure seeks to provide a method for assembling the stem neck trial component. An aim of the present disclosure is to provide a solution that overcomes at least partially the problems encountered in the prior art.
[6] In a first aspect, the present disclosure provides a stem neck trial component comprising:
a slider element having:
a stem having an offset slot extending longitudinally along the stem, said offset slot having an engagement element;
a flange portion having a top end and a bottom end opposite to the top end, wherein the bottom end of the flange portion is attached to a first end of the stem;
an indicator slot towards a second end of the stem, the second end being opposite to the first end of the stem, said indicator slot passing through the stem, wherein the indicator slot is designed to accommodate an indicator pin; and
an indentation formed circumferentially around the flange portion, between the top end and the bottom end, wherein said indentation is designed to mechanically couple the flange portion with a femoral head element;
the femoral head element having:
a hollow spherical dome having a first cavity and an opening to the first cavity, wherein said first cavity is designed to accommodate at least the flange portion that is inserted through the opening into the first cavity; and
a projection formed corresponding to the indentation of the stem, said projection being formed circumferentially in an inner surface of the hollow spherical dome, wherein said projection is received by the indentation of the stem to mechanically couple the femoral head element with the flange portion of the stem; and
a neck element having:
an elongate structure having a third end and a fourth end opposite to the third end, said fourth end being shaped with a flared configuration, wherein the elongate structure comprises:
a slider slot extending longitudinally along said elongate structure, wherein the slider slot is positioned centrally through said elongate structure, said slider slot being designed to receive the stem of the slider element;
an offset indicator slot along a portion of a length of said elongate structure, wherein the offset indicator slot is designed to accommodate linear movement of the indicator pin within said offset indicator slot when in use, and wherein the offset indicator slot has a plurality of offset markings along a length of the offset indicator slot;
a through-recess passing through the elongate structure, wherein the through-recess has a front end and a back end opposite to the front end, wherein the through-recess is adjacent to the offset indicator slot, and across the plurality of offset markings;
an interlocking arrangement that is arranged within the through-recess of the neck element, wherein a portion of said interlocking arrangement extends outside the front end and the back end of the through-recess, wherein the interlocking arrangement mechanically engages or mechanically disengages with the engagement element of the slider element; and
a broach attachment element that is designed to attach the neck element to a broach, wherein a bottom surface at the fourth end of the neck element is arranged on a first top surface of the broach,
wherein, a mechanical disengagement of the interlocking arrangement allows linear movement of the slider element in the slider slot of the neck element to adjust an offset between the femoral head element and the broach, wherein the indicator pin of the slider element moves linearly through the offset indicator slot, when in use.
[7] In a second aspect, the present disclosure provides a method for assembling the stem neck trial component as claimed in claim 1, the method comprising:
inserting at least the flange portion of the slider element through the opening of the femoral head element into the first cavity, wherein the indentation of the femoral head element is inserted into the corresponding groove of the flange portion to mechanically couple the slider element with the femoral head element;
arranging the interlocking arrangement in the through-recess of the neck element, wherein the portion of said interlocking arrangement extends outside the front end and the back end of the through-recess;
adapting the neck element to receive the stem of the slider element into the slider slot of the neck element, by mechanically engaging or mechanically disengaging the interlocking arrangement of the neck element with the engagement element of the slider element, wherein said mechanically engagement or mechanically disengagement is provided by interacting with the portion of said interlocking arrangement that extends outside the front end and the back end of the through-recess;
receiving the stem into the slider slot of the neck element, by mechanically disengaging the interlocking arrangement, wherein the engagement element faces the interlocking arrangement and the indicator pin is arranged in the offset indicator slot; and
locking the stem of the slider element in the slider slot, by mechanically engaging the interlocking arrangement with the engagement element, and
wherein, the stem neck trial component is attached to a broach via the broach attachment element, when in use.
[8] The aforementioned stem neck trial component and the method of assembly thereof incorporates a mechanism for adjustable offsets within a single trial component, thus eliminating a need for multiple neck or head components. Herein, by embedding the adjustment of the offset directly into the stem neck trial component, it is ensured that there minimized chances of misalignment, thus ensuing surgical precision when compared to conventional trial components. This also streamlines surgery for hip replacement, saving time and allowing for an efficient surgical workflow when compared to performing surgery using conventional trial components. Hence, an overall time duration of the surgery is reduced, thus lowering a risk of intraoperative complications and improving patient safety. Additionally, the stem neck trial component is cost-efficient, thus reducing a need for multiple trial implants and thus lowering cost for healthcare providers. By facilitating precise adjustments and minimizing the number of components needed, this solution improves post-operative outcomes, accelerates patient recovery, and reduces the likelihood of complications arising from improper implant placement or alignment. Overall, it represents a more efficient, precise, and cost-effective approach to hip replacement trials.
[9] It is to be appreciated that all the aforementioned implementation forms can be combined. All steps that are performed by the various entities described in the present application, as well as the functionalities described to be performed by the various entities, are intended to mean that the respective entity is adapted to or configured to perform the respective steps and functionalities. It will be appreciated that features of the present disclosure are susceptible to being combined in various combinations without departing from the scope of the present disclosure as defined by the appended claims.
[10] Additional aspects, advantages, features, and objects of the present disclosure would be made apparent from the drawings and the detailed description of the illustrative implementations construed in conjunction with the appended claims that follow.
BRIEF DESCRIPTION OF THE DRAWINGS
[11] The summary above, as well as the following detailed description of illustrative embodiments, is better understood when read in conjunction with the appended drawings. For the purpose of illustrating the present disclosure, exemplary constructions of the disclosure are shown in the drawings. However, the present disclosure is not limited to specific methods and instrumentalities disclosed herein. Moreover, those in the art will understand that the drawings are not to scale. Wherever possible, like elements have been indicated by identical numbers.
[12] Embodiments of the present disclosure will now be described, by way of example only, with reference to the following diagrams wherein:
FIG. 1 illustrates a stem neck trial component, in accordance with an embodiment of the present disclosure;
FIG. 2A illustrates a front view of the stem neck trial component of FIG. 1, FIG. 2B illustrates a perspective view of the stem neck trial component of FIG. 1, FIG. 2C illustrates a perspective view of a cross-sectional view of the stem neck trial component of FIG. 1, and FIG. 2D illustrates a top perspective view of a cross-sectional view of the stem neck trial component of FIG. 1, in accordance with an embodiment of the present disclosure; and
FIGs. 3A, 3B, and 3C illustrate sectional views of different offset assemblies of the stem neck component of FIG. 1, in accordance with an embodiment of the present disclosure.
[13] In the accompanying drawings, an underlined number is employed to represent an item over which the underlined number is positioned or an item to which the underlined number is adjacent. A non-underlined number relates to an item identified by a line linking the non-underlined number to the item. When a number is non-underlined and accompanied by an associated arrow, the non-underlined number is used to identify a general item at which the arrow is pointing.
DETAILED DESCRIPTION OF EMBODIMENTS
[14] The following detailed description illustrates embodiments of the present disclosure and ways in which they can be implemented. Although some modes of carrying out the present disclosure have been disclosed, those skilled in the art would recognize that other embodiments for carrying out or practicing the present disclosure are also possible.
[15] FIG. 1 illustrates a stem neck trial component 100, in accordance with an embodiment of the present disclosure. The stem neck trial component 100 comprises a slider element 102, a femoral head element 104, and a neck element 106. The slider element 102 has a stem 108 having an offset slot 110 extending longitudinally along the stem 108, said offset slot 110 having an engagement element (depicted as a first set of locking teeth 112A and a second set of locking teeth 112B); a flange portion 114 having a top end 116A and a bottom end 116B opposite to the top end 116A, wherein the bottom end 116B of the flange portion 114 is attached to a first end 118A of the stem 108; an indicator slot 120 towards a second end 118B of the stem 108, the second end 118B being opposite to the first end 118A of the stem 108, said indicator slot 120 passing through the stem 108, wherein the indicator slot 120 is designed to accommodate an indicator pin 122; and a indentation 124 formed circumferentially around the flange portion 114, between the top end 116A and the bottom end 116B, wherein said indentation 124 is designed to mechanically couple the flange portion 114 with the femoral head element 104.
[16] The femoral head element 104 has a hollow spherical dome 126 having a first cavity 128 and an opening 130 to the first cavity 128, wherein said first cavity 128 is designed to accommodate at least the flange portion 114 that is inserted through the opening 130 into the first cavity 128; and a projection formed corresponding to the indentation 124 of the slider element 102, said projection (not shown for sake of clarity) being formed circumferentially in an inner surface (not shown for sake of clarity) of the hollow spherical dome 126, wherein said projection is received by the indentation 124 to mechanically couple the femoral head element 104 with the flange portion 114 of the stem 108.
[17] The neck element 106 has an elongate structure 132, an interlocking arrangement 134, and a broach attachment element 136. The elongate structure 132 has a third end 138A and a fourth end 138B opposite to the third end 138A, said fourth end 138B being shaped with a flared configuration, wherein the elongate structure 132 comprises: a slider slot 140 extending longitudinally along said elongate structure 132, wherein the slider slot 140 is positioned centrally through said elongate structure 132, said slider slot 140 being designed to receive the stem 108 of the slider element 102; an offset indicator slot 142 along a portion of a length of said elongate structure 132, wherein the offset indicator slot 142 is designed to accommodate linear movement of the indicator pin 122 within said offset indicator slot 142 when in use, and wherein the offset indicator slot 142 has a plurality of offset markings (depicted as offset markings 144) along a length of the offset indicator slot 142; a through-recess 146 passing through the elongate structure 132, wherein the through-recess 146 has a front end 148 and a back end (not shown for sake of clarity) opposite to the front end 148, wherein the front end 148 is adjacent to the offset indicator slot 142, the front end 148 being across the offset markings 144.
[18] The interlocking arrangement 134 is arranged within the through-recess 146 of the neck element 106, wherein a portion of said interlocking arrangement 134 extends outside the front end 148 and the back end of the through-recess 146, wherein the interlocking arrangement 134 mechanically engages or mechanically disengages with the engagement element 112 of the slider element 102. The broach attachment element (depicted as a peg 136) is designed to attach the neck element 106 to a broach (not shown for sake of clarity), wherein a bottom surface 152 at the fourth end 138B of the neck element 106 is arranged on a first top surface of the broach. A mechanical disengagement of the interlocking arrangement 134 allows linear movement of the slider element 102 in the slider slot 140 of the neck element 106 to adjust an offset between the femoral head element 104 and the broach, wherein the indicator pin 122 of the slider element 102 moves linearly through the offset indicator slot 142, when in use.
[19] Optionally, the interlocking arrangement 134 comprises a first button 150A and a second button 150B. The first button 150A has a first circular opening 152 on a first surface 154A of the first button 150A, said first circular opening 152 being designed to accommodate a first spring 156A; and a first protrusion 158A from a second surface 154B of the first button 150A, wherein the second surface 154B is adjacent to the first surface 154A. The second button 150B has a second circular opening (not shown for the sake of clarity) on a third surface (not shown for the sake of clarity) of the second button 150B, said second circular opening being designed to accommodate a second spring 156B; and a second protrusion 158B from a fourth surface 154C of the second button 150B, wherein the fourth surface 154C is adjacent to the third surface.
[20] Optionally, the neck element 106 further has a neck block element 160 having a third protrusion 162, wherein said third protrusion 162 has a fifth surface 164 and a sixth surface (not shown for the sake of clarity) opposite to the fifth surface 164, wherein the elongate structure 132 of the neck element 106 further comprises a second cavity 166 passing through the elongate structure 132, said second cavity 166 is arranged between the front end 148 and the back end of the through-recess 146, wherein the second cavity 166 is designed to accommodate the neck block element 160 such that the third protrusion 162 is arranged between the first spring 156A of the first button 150A and the second spring 156B of the second button 150B.
[21] Throughout the present disclosure, the term "stem neck trial component" refers to a portion of a femoral component, where stem and neck of a femur meet. In other words, the term "stem neck trial component" refers to a temporary component that is used during a hip arthroplasty to help a surgeon to determine a correct size, alignment, and fit of a final implant. Herein, the final implant includes a stem neck implant and a femoral stem implant. In this regard, damaged components of the femur are replaced with the final implant. During surgery, before the final implant is implanted, trial components are used that mimic a shape and a size of the final implant. The stem neck trial component 100 in particular, is used to check at least one of: how well the stem neck trial component 100 aligns with the hip socket, whether the offset provides adequate leg length and stability, how much range of motion the hip has. In case the stem neck trial component 100 does not fit correctly, the offset between the femoral head component and the broach can be adjusted before finalizing the final implant. A technical effect of using the stem neck trial component 100 is that a best anatomical fit and function is provided to a patient, which minimizes complications (for example, such as dislocations, discrepancies of leg length, and so forth).
[22] Throughout the present disclosure, the term "slider element" refers to a mechanical component that is designed to move linearly in the slider slot 140. The slider element 102 is used to control and/or adjust the offset between the femoral head component and the broach. The stem 108 of the slider element 102 is an elongated, cylindrical part that extends from the first end 118A to the second end 118B that is opposite to the first end 118A. The flange portion 114 of the slider element 102 is circular or a disc-shaped component that is attached to the first end 118A of the stem 108, wherein the flange portion 114 has a diameter that is wider than the stem 108 itself. The indentation 124 is formed circumferentially around said flange portion 114. The slider element 102 is designed to fit within the indentation 124 of the flange portion 114, to ensure that the slider element 102 and the femoral head component are aligned correctly. The stem 108 has the indicator slot 120, which is designed to receive and guide the indicator pin 122. Herein, the indicator pin 122 is a movable component that fits into the indicator slot 120. The indicator pin 122 is used to provide a visual or mechanical indication of a position (for example, such as extension or retraction) of the stem 108. In this regard, a position of the indicator pin 122 (upon assembly of the stem neck trial component 100) can be correlated with a position of the stem 108. The engagement element 112 is at least one of: a projection, a groove, that is designed to interact with the interlocking arrangement 134.
[23] In an embodiment, the engagement element comprises the first set of locking teeth and the second set of locking teeth opposite to the first set of teeth, arranged longitudinally along the first slot. The first set of locking teeth and the second set of locking teeth allows for a secure mechanical connection between the slider element 102 and the neck element 106. When the stem 108 is inserted into the slider slot 140, the first set of locking teeth and the second set of locking teeth engages with the interlocking arrangement 134. Such mechanism prevents the slider element 102 from moving independently within the slider slot 140. A technical effect of the aforementioned feature is that it facilitates controlled movement of the slider element 102, to adjust the offset between the femoral head element 104 and the broach.
[24] In an embodiment, a number of locking teeth in the first set of locking teeth and the second set of locking teeth is based on the offset between the femoral head structure and the broach. Herein, the number of locking teeth in the first set of locking teeth and the second set of locking teeth is adjusted to match a displacement between the femoral head element 104 and the broach. In this regard, the offset between the femoral head element 104 and the broach is determined. Subsequently, the number of locking teeth in the first set of locking teeth and the second set of locking teeth is adjusted to correspond to the offset. When the engagement element 112 is inserted into the slider slot 140, the first set of locking teeth and the second set of locking teeth mechanically engage with the interlocking arrangement 134. A technical effect of the aforementioned feature is that it facilitates adjusting the number of locking teeth to ensure accurate alignment between the femoral head element 104 and the broach.
[25] Throughout the present disclosure, the term "femoral head element" refers to a spherical component that represents a head of the femur in hip arthroplasty. The femoral head element 104 is designed to move around within the hip socket. When assembling the slider element 102 with the femoral head element 104, the slider element 102 is arranged coaxially with the femoral head element 104. The flange portion 114 is inserted through the opening 130 into the first cavity 128, thus creating a physical connection between the femoral head element 104 and the slider element 102. In this regard, the opening 130 ensures that the flange portion 114 is inserted into the cavity in a correct orientation. The indentation 124 on the flange portion 114 is then mechanically coupled with the projection of the femoral head element 104. Herein, the projection of the femoral head element 104 aligns with the indentation 124 of the slider element 102, thus preventing the femoral head element 104 from dislocating.
[26] Optionally, the femoral head element 104 also has another opening that is opposite to the opening 130 to the first cavity 128, wherein the another opening is arranged co-axially with respect to the opening 130. The another opening is used to release air when the slider element 102 is linearly moved to adjust the offset between the femoral head element 104 and the broach, when in use.
[27] Throughout the present disclosure, the term "neck element" refers to a support structure for the slider element 102, that allows said slider element 102 to move linearly. The neck element 106 has the elongate structure 132, wherein the fourth end 138B is wider or broader than rest of the elongate structure 132, thus creating the flared configuration. Such flared configuration facilitates a connection with the broach, wherein a dimension of the flared configuration corresponds to a dimension of the first top surface of the broach. Herein, the elongate structure 132 comprises the slider slot 140, the offset indicator slot 142, and the through-recess 146. Herein, the term "slider slot" refers to a slot running through the length of the elongate structure 132, and centrally-positioned. The slider slot 140 allows for linear movement of the slider element 102 along the length of the elongate structure 132.
[28] The term "offset indicator slot" refers to a slot that is located along the portion of the elongate structure 132, parallel to the slider slot 140. The offset indicator slot 142 is designed to receive and guide the indicator pin 122, to provide an indication of the offset or position of the slider element 102. Moreover, the plurality of offset markings 144 on the offset indicator slot 142 can be used to visually correlate the position of the indicator pin 122 with the offset of the slider element. In this regard, the plurality of offset markings 144 facilitates streamlining the hip arthroplasty by reducing a need for trial and error. The term "through-recess" refers to a passageway that extends through an entire width of the elongate structure 132. The through-recess 146 is located adjacent to the offset indicator slot 142.
[29] In an embodiment, the plurality of offset markings 144 comprise preset offsets marked along the offset indicator slot 142, wherein said preset offsets correspond to different sizes of a stem neck implant. Herein, the term "preset offsets" represent specific distances that correspond to the different sizes of the stem neck implant. Each preset offset represents a specific size of the stem neck implant. In this regard, by observing the position of the indicator pin 122 relative to the plurality of offset markings 144, the stem neck implant of an appropriate size can be selected. For example, the preset offsets may be -4, 0, +7, and so forth. A technical effect of the aforementioned feature is that facilitates adjusting the offset of the stem neck trial component 100 based on the common sizes of the stem neck implant.
[30] Throughout the present disclosure, the term "interlocking arrangement" refers to a mechanism that fits within the through-recess 146 and is designed to engage or disengage with the engagement element 112 of the slider element 102. The interlocking arrangement 134 is designed to provide a secure and reliable connection between the slider element 102 and the neck element 106. The interlocking arrangement 134 can be designed to allow for intentional disengagement. This may be achieved through a mechanical release mechanism.
[31] In an embodiment, the interlocking arrangement 134 comprises:
a first button 150A having:
a first circular opening 152 on a first surface 154A of the first button 150A, said first circular opening 152 being designed to accommodate a first spring 156A; and
a first protrusion 158A from a second surface 154B of the first button 150A, wherein the second surface 154B is adjacent to the first surface 154A; and
a second button 150B having:
a second circular opening on a third surface of the second button 150B, said second circular opening being designed to accommodate a second spring 156B; and
a second protrusion 158B from a fourth surface 154C of the second button 150B, wherein the fourth surface 154C is adjacent to the third surface,
wherein a portion of the first spring 156A and a portion of the second spring 156B are accommodated inside the first circular opening 152 and the second circular opening, respectively,
wherein when the interlocking arrangement 134 is arranged within the through-recess 146 of the neck element 106, the first button 150A is arranged at the front end 148 such that a portion of the first button 150A extends outside the first end 118A, and the second button 150B is arranged at the second end 118B such that a portion of the second button 150B extends outside the second end 118B, wherein the first spring 156A and the second spring 156B that extend from the first circular opening 152 and the second circular opening, respectively, face towards each other,
wherein the first protrusion 158A and the second protrusion 158B are arranged adjacent to the first set of locking teeth and the second set of locking teeth, respectively, wherein a space between adjacent teeth of each of the first set and the second set accommodate the first protrusion 158A and the second protrusion 158B, respectively.
[32] In this regard, the first button 150A and the second button 150B are arranged within the through-recess 146, wherein the portion of the first button 150A is exposed through the first end 118A and the portion of the second button 150B is exposed through the second end. The first spring 156A is attached within the first circular opening 152 of the first button 150A, and the second spring 156B is attached within the second circular opening of the second button 150B. Herein, the portion of the first spring 156A and the portion of the second spring 156B are attached within the first circular opening 152 and the second circular opening, respectively, such that a remaining portion of the first spring 156A and a remaining portion of the second spring 156B are exposed. Moreover, the first protrusion 158A and the second protrusion 158B engage with the first set of locking teeth and the second set of locking teeth, respectively, when corresponding first spring 156A and the second spring 156B are compressed. Herein, a space between the adjacent teeth in each of the first set and the second set accommodates the corresponding first protrusion 158A and the second protrusion 158B. This compression creates a force that pushes the first button 150A and the second button 150B together.
[33] When the first button 150A and the second button 150B are pushed in a manner that they are brought together, the first spring 156A and the second spring 156B, respectively, are compressed. The first protrusion 158A and the second protrusion 158B, respectively, mechanically disengage with the first set and the second set of locking teeth, to allow linear movement of the slider element 102. Moreover, when the first button 150A and the second button 150B are released, the first spring 156A and the second spring 156B, respectively, expand. The first protrusion 158A and the second protrusion 158B, respectively, mechanically disengage with the first set and the second set of locking teeth, to create a mechanical connection with the engagement element 112, that is secure in nature. A technical effect of the aforementioned feature is that the first button 150A and the second button 150B can be easily used to lock (i.e., mechanically engage) and unlock (i.e., mechanically disengage) to allow linear movement of the slider element 102.
[34] In another embodiment, a single spring is accommodated within the first circular opening 152 and the second circular opening, wherein when the interlocking arrangement 134 is arranged within the through-recess 146 of the neck element 106, only the single spring is shared by the first button 150A and the second button 150B. This single spring is compressed and expanded to mechanically disengage and engage with the engagement means.
[35] In an embodiment, when the interlocking arrangement 134 is arranged within the through-recess 146 of the neck element 106, the first button 150A and the second button 150B are pressed towards each other to compress the first spring 156A and the second spring 156B, respectively, to allow the stem 108 of the slider element 102 move linearly inside the slider slot 140 of the neck element 106 such that the indicator pin 122 of the slider element 102 moves linearly inside the offset indicator slot 142, and
the first button 150A and the second button 150B are released to decompress the first spring 156A and the second spring 156B, respectively, to mechanically engage the first protrusion 158A of the first button 150A with the first set of locking teeth, and the second protrusion 158B of the second button 150B with the second set of locking teeth, and lock the slider element 102 inside the slider slot 140, when in use.
[36] In this regard, this mechanism allows for controlled linear movement of the slider element 102. Such mechanism is used to assemble the slider element 102 into the slider slot 140 of the neck element 106. The first protrusion 158A and the second protrusion 158B initially are mechanically disengaged, to allow the stem 108 to be received into the slider slot 140. At a particular position, the first button 150A and the second button 150B are released to mechanically engage the first protrusion 158A and the second protrusion 158B with the first set of locking teeth and the second set of locking teeth, respectively. A technical effect of the aforementioned feature is that it enables linear movement of the slider element 102, and precents the slider element 102 from moving unintentionally.
[37] In an embodiment, the neck element 106 further has a neck block element 160 having a third protrusion, wherein said third protrusion has a fifth surface 164 and a sixth surface opposite to the fifth surface 164,
wherein the elongate structure 132 of the neck element 106 further comprises a second cavity 166 passing through the elongate structure 132, said second cavity 166 is arranged between the front end 148 and the back end of the through-recess 146, wherein the second cavity 166 is designed to accommodate the neck block element 160 such that the third protrusion is arranged between the first spring 156A of the first button 150A and the second spring 156B of the second button 150B,
wherein the first spring 156A of the first button 150A is arranged against the fifth surface 164 of the third protrusion and the second spring 156B of the second button 150B is arranged against the sixth surface of the protrusion.
[38] Herein, the neck block element 160 is positioned within the second cavity 166. The third protrusion on the neck block element 160 is positioned between the first spring 156A of the first button 150A and the second spring 156B of the second spring 156B. Herein, the third protrusion provides a rigid support to the first spring 156A and the second spring 156B, such that when the first button 150A and the second button 150B, respectively, are pressed together, the first spring 156A and the second spring 156B are compressed against the third protrusion. The third protrusion helps to distribute forces from the first spring 156A and the second spring 156B, respectively. A technical effect of the third protrusion is to maintain a stability and an alignment of the neck element 106.
[39] Optionally, the neck block element 160 is snug-fit into the second cavity 166. Alternatively, optionally, the neck block element 160 is fastened into the second cavity 166 using a fastening element. Examples of the fastening element may include, but are not limited to, a screw, a rivet, and a bolt.
[40] In an embodiment, when the interlocking arrangement 134 is arranged within the through-recess 146 of the neck element 106, and when the stem 108 of the slider element 102 is arranged inside the slider slot 140 of the neck element 106, the first button 150A and the second button 150B are pressed towards each other and subsequently released to perform any one of:
mechanically disengage and engage at a first offset value, such that there is a predefined gap 302 between a bottom surface at the bottom end 116A of the flange portion 114 and a second top surface at the third end 138A of the elongate structure 132 of the neck element 106, when in use;
mechanically disengage and engage at a second offset value, such that there is no gap between the bottom surface of the flange portion 114 and the second top surface of the elongate structure 132 of the neck element 106, when in use;
mechanically disengage and engage at a second offset value, such that there is another predefined gap 304 between the bottom surface of the flange portion 114 and the second top surface of the elongate structure 132 of the neck element 106, the another predefined gap 304 being greater than the predefined gap 302, when in use,
wherein the preset offsets comprise the first offset value, the second offset value and the third offset value.
[41] In this regard, when the interlocking arrangement 134 is positioned inside the through-recess 146 of the neck element 106, it interfaces with the stem 108 of the slider element 102 located in the slider slot 140. The pressing of the first button 150A and the second button 150B allows the slider element 102 to be adjusted or toggled between different mechanical configurations. Upon pressing and releasing the first button 150A and the second button 150B, the interlocking arrangement 134 mechanically engages and disengages at a particular offset value. Moreover, the first offset value, the second offset value, and the third offset value correspond to different configurations of gap distances between the flange and the top surface of the elongate structure 132. These offset values are preset, thus allowing the mechanism to switch between them without a need for external calibration during calibration. A technical effect of the aforementioned feature is to facilitate easy switching between configurations, allowing for adapting to different operational requirements. Moreover, the mechanical disengagement and the mechanical engagement mechanism ensures that once any one of the first offset value, the second offset value, and the third offset value is selected, the slider element 102 is securely locked with the interlocking arrangement 134.
[42] Throughout the present disclosure, the term "broach attachment element" refers to a component that is designed to connect the neck element 106 to the broach. Herein, the broach is a specialized tool used to enlarge a hole (specifically, a medullary cavity) in the femur. The bottom surface of the neck element 106 is positioned on the first top surface of the broach, ensuring proper alignment.
[43] When the stem neck trial component 100 is assembled, the interlocking arrangement 134 is mechanically disengaged, which allows the slider element 102 to move freely within the slider slot 140. This movement can be used to adjust the position of the femoral head element 104 relative to the broach. In this regard, as the slider element 102 moves, the indicator pin 122 within the offset indicator slot 142 also moves. Such movement of the indicator pin 122 provides a visual indication of the offset adjustment.
[44] In an embodiment, the broach attachment element comprises a peg 136 and an attachment slot corresponding to a broach attachment slot and a broach peg of the broach. In this regard, the term "peg" refers to a protruding part that is designed to fit into a corresponding slot of the broach. The term "attachment slot" refers to a recessed part that receives the corresponding broach peg 136 of the broach. Herein, the peg 136 of the broach attachment element is inserted into the broach attachment slot, and the attachment slot of the broach attachment element receives the broach peg. This ensures that the stem neck trial component 100 and the broach attachment element are held tightly together, allowing them to function as a single, integrated tool during the hip arthroplasty. A technical effect of the aforementioned feature is that it facilitates ease of attachment and detachment, thus ensuring that the stem neck trial component 100 can be easily connected or disconnected as required. Moreover, such connection prevents any unintended movement or detachment from use. Another technical effect of the aforementioned feature is that the stem neck trial component 100 is properly aligned with the broach attachment element, thus contributing to faster workflow and reduced operating time.
[45] Optionally, a material for manufacturing at least one of: the slider element 102, the femoral head element 104, the neck element 106, the indicator pin 122, the neck block element 160, the interlocking arrangement 134 (i.e., the first button 150A, the second button 150B, the first spring 156A of the first button 150A, the second spring 156A of the second button 150A) is at least one of: a titanium material, a cobalt chromium material, a plastic material, a stainless steel 316 (SS 316) material. A technical effect of selecting the material is that it impacts a biocompatibility, a strength, a durability, a weight, and an overall performance of the stem neck trial component 100.
[46] FIG. 2A illustrates a front view of the stem neck trial component 100 of FIG. 1, FIG. 2B illustrates a perspective view of the stem neck trial component 100 of FIG. 1, FIG. 2C illustrates a perspective view of a cross-sectional view of the stem neck trial component 100 of FIG. 1, and FIG. 2D illustrates a top perspective view of a cross-sectional view of the stem neck trial component 100 of FIG. 1, in accordance with an embodiment of the present disclosure.
[47] In FIG. 2A, there is illustrated a cross-sectional view of the femoral head element 104, taken along Y-axis. Herein, the stem neck trial component 100 comprises the slider element 102, the femoral head element 104, the neck element 106. The slider element 102 has the stem 108, the flange portion 114, the indentation 202 formed circumferentially around the flange portion 114. The femoral head element 104 has a hollow spherical dome 126 having the first cavity 128 and an opening 130 (not shown for sake of clarity) to the first cavity 128.
[48] The neck element 106 has the elongate structure 132 having the third end 138A and the fourth end 138B opposite to the third end 138A, said fourth end 138B being shaped with a flared configuration. The elongate structure 132 comprises a slider slot 140 (not shown in this figure for the sake of clarity) extending longitudinally along said elongate structure 132, wherein the slider slot 140 is positioned centrally through said elongate structure 132, the offset indicator slot 142 along a portion of a length of said elongate structure 132, a through-recess 146 (not shown in this figure for the sake of clarity) passing through the elongate structure 132. The slider slot 140 is designed to receive the stem 108 of the slider element 102. The offset indicator slot 142 is designed to accommodate linear movement of an indicator pin 122 within said offset indicator slot 142, when in use, wherein the offset indicator slot 142 has the offset markings 144 along the length of the offset indicator slot 142. An interlocking arrangement 134 is arranged within the through-recess 146. The neck element 106 comprises the peg 136.
[49] In FIG. 2B, there is illustrated a left perspective view of an arrangement of the slider element 102 with the neck element 106. The slider element 102 is arranged within the slider slot 140 of the neck element 106. The elongate structure 132 further comprises a second cavity 166 passing through the elongate structure 132. The interlocking arrangement 134 comprises the first button 150A, the second button 150B, the first spring 156A of the first button 150A, and the second spring 156B of the second button 150B.
[50] In FIG. 2C, there is illustrated the cross-sectional view of the stem neck trial component 100, taken along YZ-axis. Herein, all components of the stem neck trial component 100 are assembled. In this regard, the interlocking arrangement 134 is clearly illustrated, wherein the interlocking arrangement 134 comprises the first button 150A, the second button 150B, the first spring 156A of the first button 150A, and the second spring 156B of the second button 150B. The first spring 156A and the second spring 156B are held by the protrusion 162 of the neck block element 160.
[51] FIGs. 3A, 3B, and 3C illustrate sectional views of different offset assemblies of the stem neck trial component 100 of FIG. 1, in accordance with an embodiment of the present disclosure. The stem neck trial component 100 in FIGs. 3A-3C comprises the slider element 102, the femoral head element 104, the neck element 106, the indicator pin 122, and the neck block element 160.
[52] The interlocking arrangement 134 is arranged within the through-recess 146 of the neck element 106, and the stem 108 of the slider element 102 is arranged inside the slider slot 140 of the neck element 106. In FIG. 3A, the first button 150A and the second button 150B are pressed towards each other and subsequently released to mechanically disengage and engage at a first offset value (for example, such as 0 offset value), such that there is the predefined gap 302 between the bottom surface at the bottom end 116B of the flange portion 114 and a second top surface at the third end 138A of the elongate structure 132 of the neck element 106, when in use. In FIG. 3B, the first button 150A and the second button 150B are pressed towards each other and subsequently released to mechanically disengage and engage at a second offset value (for example, such as -4 offset value), such that there is no gap between the bottom surface of the flange portion 114 and the second top surface of the elongate structure 132 of the neck element 106, when in use. In FIG. 3C, the first button 150A and the second button 150B are pressed towards each other and subsequently released to mechanically disengage and engage at a second offset value (for example, such as +7 offset value), such that there is another predefined gap 304 between the bottom surface of the flange portion 114 and the second top surface of the elongate structure 132 of the neck element 106, the another predefined gap 304 being greater than the predefined gap 302, when in use.
[53] FIG. 4 illustrates a flowchart 400 of steps of a method for assembling the stem neck trial component 100 of FIG. 1, in accordance with an embodiment of the present disclosure. At step 402, at least the flange portion 114 of the slider element 102 is inserted through the opening 130 of the femoral head element 104 into the first cavity 128, wherein the projection of the femoral head element 104 is inserted into the corresponding indentation 124 of the flange portion 114 to mechanically couple the slider element 102 with the femoral head element 104. At step 404, the interlocking arrangement 134 is arranged in the through-recess 146 of the neck element 106, wherein the portion of said interlocking arrangement 134 extends outside the front end 148 and the back end of the through-recess 146. At step 406, the neck element 106 is adapted to receive the stem 108 of the slider element 102 into the slider slot 140 of the neck element 106, by mechanically engaging or mechanically disengaging the interlocking arrangement 134 of the neck element 106 with the engagement element 112 of the slider element 102, wherein said mechanically engagement or mechanically disengagement is provided by interacting with the portion of said interlocking arrangement 134 that extends outside the front end 148 and the back end of the through-recess 146. At step 408, the stem 108 is received into the slider slot 140 of the neck element 106, by mechanically disengaging the interlocking arrangement 134, wherein the engagement element 112 faces the interlocking arrangement 134, and the indicator pin 122 is arranged in the offset indicator slot 142. At step 410, the stem 108 of the slider element 102 is locked in the slider slot 140, by mechanically engaging the interlocking arrangement 134 with the engagement element 112, wherein the stem neck trial component 100 is attached to a broach via the broach attachment element, when in use.
[54] Herein, the aforementioned method outlines the assembly of the stem neck trial component 100 by integrating the slider element 102, the femoral head element 104, and the neck element 106. The flange portion 114 of the slider element 102 is inserted through the projection of the femoral head element 104 into the first cavity 128. Herein, the projection on the femoral head element 104 aligns with and is inserted into the indentation 124 of the flange portion 114. This creates a mechanical fit between the slider element 102 and the femoral head element 104, thus ensuring that they are connected for subsequent steps.
[55] Moreover, the interlocking arrangement 134 is placed within the through-recess 146 of the neck element 106, wherein the portion of the interlocking arrangement 134 extends beyond both the front end 148 and the back end of the through-recess 146. This ensures that the interlocking arrangement 134 can interact with other components from both ends, thus enabling mechanical engagement and disengagement for alignment and adjustment of the offset. Thereafter, the interlocking arrangement 134 mechanically disengages and mechanically engages with the engagement element 112 of the slider element 102, by interacting with the portion of the interlocking arrangement 134 that extends from the front end 148 and the back end of the through-recess 146. Such mechanical disengagement and mechanical engagement allow for secure locking and unlocking of the slider element 102 within the slider slot 140 of the neck element 106. Moreover, as the stem 108 of the slider element 102 enters the slider slot 140, the interlocking arrangement 134 is mechanically disengaged to allow the stem 108 to fit properly. During this arrangement, the engagement element 112 on the slider element 102 is aligned to face the interlocking arrangement 134. Additionally, the indicator pin 122 is arranged into the offset indicator slot 142, which serves as a reference for alignment during the assembly of the stem neck trial component 100. Finally, the stem of the slider element 102 is locked into place within the slider slot 140 by mechanically engaging the interlocking arrangement 134 with the engagement element 112. This secures the stem in a fixed position, thus preventing any unwanted movement or disassembly, when in use. Thereafter, the stem neck trial component 100 is arranged on the broach, and mechanically coupled with said broach via the broach attachment element.
[56] Modifications to embodiments of the present disclosure described in the foregoing are possible without departing from the scope of the present disclosure as defined by the accompanying claims. Expressions such as "including", "comprising", "incorporating", "have", "is" used to describe and claim the present disclosure are intended to be construed in a non-exclusive manner, namely allowing for items, components or elements not explicitly described also to be present. Reference to the singular is also to be construed to relate to the plural. The word "exemplary" is used herein to mean "serving as an example, instance or illustration". Any embodiment described as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments and/or to exclude the incorporation of features from other embodiments. The word "optionally" is used herein to mean "is provided in some embodiments and not provided in other embodiments". It is appreciated that certain features of the present disclosure, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the present disclosure, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable combination or as suitable in any other described embodiment of the disclosure.
, Claims:We claim:
1. A stem neck trial component (100) comprising:
a slider element (102) having:
a stem (108) having an offset slot (110) extending longitudinally along the stem, said offset slot having an engagement element (112);
a flange portion (114) having a top end (116A) and a bottom end (116B) opposite to the top end, wherein the bottom end of the flange portion is attached to a first end (118A) of the stem;
an indicator slot (120) towards a second end (118B) of the stem, the second end being opposite to the first end of the stem, said indicator slot passing through the stem, wherein the indicator slot is designed to accommodate an indicator pin (122); and
an indentation (124) formed circumferentially around the flange portion, between the top end and the bottom end, wherein said indentation is designed to mechanically couple the flange portion with a femoral head element (104);
the femoral head element having:
a hollow spherical dome (126) having a first cavity (128) and an opening (130) to the first cavity, wherein said first cavity is designed to accommodate at least the flange portion that is inserted through the opening into the first cavity; and
a projection (202) formed corresponding to the indentation of the stem, said projection being formed circumferentially in an inner surface of the hollow spherical dome, wherein said projection is received by the indentation of the stem to mechanically couple the femoral head element with the flange portion of the stem; and
a neck element (106) having:
an elongate structure (132) having a third end (138A) and a fourth end (138B) opposite to the third end, said fourth end being shaped with a flared configuration, wherein the elongate structure comprises:
a slider slot (140) extending longitudinally along said elongate structure, wherein the slider slot is positioned centrally through said elongate structure, said slider slot being designed to receive the stem of the slider element;
an offset indicator slot (142) along a portion of a length of said elongate structure, wherein the offset indicator slot is designed to accommodate linear movement of the indicator pin within said offset indicator slot when in use, and wherein the offset indicator slot has a plurality of offset markings (144) along a length of the offset indicator slot;
a through-recess (146) passing through the elongate structure, wherein the through-recess has a front end (148) and a back end opposite to the front end, wherein the through-recess is adjacent to the offset indicator slot, and across the plurality of offset markings;
an interlocking arrangement (134) that is arranged within the through-recess of the neck element, wherein a portion of said interlocking arrangement extends outside the front end and the back end of the through-recess, wherein the interlocking arrangement mechanically engages or mechanically disengages with the engagement element of the slider element; and
a broach attachment element that is designed to attach the neck element to a broach, wherein a bottom surface at the fourth end of the neck element is arranged on a first top surface of the broach,
wherein, a mechanical disengagement of the interlocking arrangement allows linear movement of the slider element in the slider slot of the neck element to adjust an offset between the femoral head element and the broach, wherein the indicator pin of the slider element moves linearly through the offset indicator slot, when in use.
2. The stem neck trial component (100) as claimed in claim 1, wherein the engagement element (112) comprises a first set of locking teeth and a second set of locking teeth opposite to the first set of teeth, arranged longitudinally along the first slot.
3. The stem neck trial component (100) as claimed in claim 2, wherein a number of locking teeth in the first set of locking teeth and the second set of locking teeth is based on the offset between the femoral head structure and the broach.
4. The stem neck trial component (100) as claimed in claim 3, wherein the interlocking arrangement (134) comprises:
a first button (150A) having:
a first circular opening (152) on a first surface (154A) of the first button, said first circular opening being designed to accommodate a first spring (156A); and
a first protrusion (158A) from a second surface (154B) of the first button, wherein the second surface is adjacent to the first surface; and
a second button (150B) having:
a second circular opening on a third surface of the second button, said second circular opening being designed to accommodate a second spring (156B); and
a second protrusion (158B) from a fourth surface (154C) of the second button, wherein the fourth surface is adjacent to the third surface,
wherein a portion of the first spring and a portion of the second spring are accommodated inside the first circular opening and the second circular opening, respectively,
wherein when the interlocking arrangement is arranged within the through-recess (146) of the neck element (106), the first button is arranged at the front end (148) such that a portion of the first button extends outside the first end (118A), and the second button is arranged at the second end (118B) such that a portion of the second button extends outside the second end, wherein the first spring and the second spring that extend from the first circular opening and the second circular opening, respectively, face towards each other,
wherein the first protrusion and the second protrusion are arranged adjacent to the first set of locking teeth and the second set of locking teeth, respectively, wherein a space between adjacent teeth of each of the first set and the second set accommodate the first protrusion and the second protrusion, respectively.
5. The stem neck trial component (100) as claimed in claim 4, wherein when the interlocking arrangement (134) is arranged within the through-recess (146) of the neck element (106), the first button (150A) and the second button (150B) are pressed towards each other to compress the first spring (156A) and the second spring (156B), respectively, to allow the stem (108) of the slider element (102) move linearly inside the slider slot (140) of the neck element such that the indicator pin (122) of the slider element moves linearly inside the offset indicator slot (142), and
the first button and the second button are released to decompress the first spring and the second spring, respectively, to mechanically engage the first protrusion (158A) of the first button with the first set of locking teeth, and the second protrusion (158B) of the second button with the second set of locking teeth, and lock the slider element inside the slider slot, when in use.
6. The stem neck trial component (100) as claimed in claim 4, wherein the neck element (106) further has a neck block element (160) having a third protrusion (162), wherein said third protrusion has a fifth surface (164) and a sixth surface opposite to the fifth surface,
wherein the elongate structure (132) of the neck element further comprises a second cavity (166) passing through the elongate structure, said second cavity is arranged between the front end (148) and the back end of the through-recess (146), wherein the second cavity is designed to accommodate the neck block element such that the third protrusion is arranged between the first spring (156A) of the first button (150A) and the second spring (156B) of the second button (150B),
wherein the first spring of the first button is arranged against the fifth surface of the third protrusion and the second spring of the second button is arranged against the sixth surface of the third protrusion.
7. The stem neck trial component (100) as claimed in claim 1, wherein the plurality of offset markings (144) comprise preset offsets marked along the offset indicator slot (142), wherein said preset offsets correspond to different sizes of a stem neck implant.
8. The stem neck trial component (100) as claimed in 7, wherein when the interlocking arrangement (134) is arranged within the through-recess (146) of the neck element (106), and when the stem (108) of the slider element (102) is arranged inside the slider slot (140) of the neck element, the first button (150A) and the second button (150B) are pressed towards each other and subsequently released to perform any one of:
mechanically disengage and engage at a first offset value, such that there is a predefined gap (302) between a bottom surface at the bottom end (116B) of the flange portion (114) and a second top surface at the third end (138A) of the elongate structure (132) of the neck element, when in use;
mechanically disengage and engage at a second offset value, such that there is no gap between the bottom surface of the flange portion and the second top surface of the elongate structure of the neck element, when in use;
mechanically disengage and engage at a second offset value, such that there is another predefined gap (304) between the bottom surface of the flange portion and the second top surface of the elongate structure of the neck element, the another predefined gap being greater than the predefined gap, when in use,
wherein the preset offsets comprise the first offset value, the second offset value and the third offset value.
9. The stem neck trial component (100) as claimed in claim 1, wherein the broach attachment element comprises a peg 136 and an attachment slot corresponding to a broach attachment slot and a broach peg of the broach.
10. A method for assembling the stem neck trial component (100) as claimed in claim 1, the method comprising:
inserting at least the flange portion (114) of the slider element (102) through the opening (130) of the femoral head element (104) into the first cavity (128), wherein the indentation (124) of the femoral head element is inserted into the corresponding groove of the flange portion to mechanically couple the slider element with the femoral head element;
arranging the interlocking arrangement (134) in the through-recess (146) of the neck element (106), wherein the portion of said interlocking arrangement extends outside the front end (148) and the back end of the through-recess;
adapting the neck element to receive the stem (108) of the slider element into the slider slot (140) of the neck element, by mechanically engaging or mechanically disengaging the interlocking arrangement of the neck element with the engagement element (112) of the slider element, wherein said mechanically engagement or mechanically disengagement is provided by interacting with the portion of said interlocking arrangement that extends outside the front end and the back end of the through-recess;
receiving the stem (108) into the slider slot of the neck element, by mechanically disengaging the interlocking arrangement, wherein the engagement element faces the interlocking arrangement and the indicator pin (122) is arranged in the offset indicator slot (142); and
locking the stem (108) of the slider element in the slider slot, by mechanically engaging the interlocking arrangement with the engagement element, and
wherein, the stem neck trial component is attached to a broach via the broach attachment element, when in use.