Description:FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(Section 10 and Rule 13)

1. TITLE OF THE INVENTION:
A TRIAL LINER ASSEMBLY FOR AN ACETABULUM PROSTHETIC DEVICE
2. APPLICANT:
Meril Corporation (I) Private Limited, an Indian company of the address Survey No. 135/139, Muktanand Marg, Bilakhia House, Pardi, Vapi, Valsad-396191 Gujarat, India.

The following specification particularly describes the invention and the manner in which it is to be performed:

FIELD OF THE INVENTION
[001] The present disclosure relates to an acetabulum prosthetic device. More particularly, the present disclosure relates to a trial liner assembly for an acetabulum prosthetic device.
BACKGROUNDOF THE INVENTION
[002] Typically, during a hip replacement surgery, a proper fit and alignment of a prosthetic device is important for the success of the surgery. Usually, surgeons heavily rely on a performance of trial liners during preoperative assessments to make informed decisions regarding implant selection and placement. However, misalignment between trial liners and implant cups can lead to misleading results and can also result in revision of surgery.
[003] When a trial liner fits well with the trial cup but not with the implant cup, it can introduce significant risks. These risks include post-surgical complications such as instability, dislocation, or impingement, which can compromise a patient's recovery and necessitate additional surgical interventions. Discovering such mismatches during surgery can also cause delays as the surgeons may have to make adjustments or secure a different implant cup. The delay leads to discomfort and inconvenience to the patient undergoing surgery.
[004] A conventional trial liner assembly does not enable a surgeon to test whether the trial liner fits with the actual implant cup. It is possible therefore, that there is a mismatch between the actual liner and the actual implant cup. This may result in a revision surgery, which not only increases the patient’s trauma but also increases the medical cost.
[005] In light of above-mentioned challenges, there is a need for a trial liner assembly that overcomes problems associated with the conventional trial liner assemblies.
SUMMARYOF THE INVENTION
[006] Particular embodiments of the present disclosure are described herein below with reference to the accompanying drawings, however, it is to be understood that the disclosed embodiments are mere examples of the disclosure, which may be embodied in various forms. Well-known functions or constructions are not described in detail to avoid obscuring the present disclosure in unnecessary detail. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present disclosure in virtually any appropriately detailed structure.
[007] The present disclosure relates to a trial liner assembly. In an embodiment, the trial liner assembly includes a trial liner, a fastener and a locking member. The trial liner includes a bearing portion on an inner surface and a first channel extended distally from a center of the bearing portion. The first channel includes a bottom face. The fastener is removably disposed within the trial liner and is configured to detachably couple the trial liner with at least one of a trial acetabular shell or an implant acetabular shell. The locking member is disposed in the first channel and is configured to prevent displacement of the fastener in the proximal direction, wherein at least a portion of the fastener resides between the locking member and the bottom face.
BRIEF DESCRIPTION OF THE DRAWINGS
[008] The summary above and the detailed description of descriptive embodiments, is better understood when read in conjunction with the apportioned drawings. For illustration of the present disclosure, exemplary constructions of the disclosure are shown in the drawings. However, the disclosure is not limited to specific methods and instrumentality disclosed herein. Moreover, those in the art will understand that the drawings are not to scale.
[009] FIG. 1 illustrates a cross section view of a trial liner assembly 100, according to an embodiment of the present disclosure;
[0010] FIG. 2 illustrates a top view of the trial liner assembly 100, according to an embodiment of the present disclosure;
[0011] FIG. 3 illustrates a front view of the trial liner assembly 100, according to an embodiment of the present disclosure;
[0012] FIG. 4 illustrates a trial liner 1 of the trial liner assembly 100, according to an embodiment of the present disclosure;
[0013] FIG. 5 illustrates a cross-section view of the trial liner 1 of the trial liner assembly 100, according to an embodiment of the present disclosure;
[0014] FIG. 6 illustrates a fastener 2 of the trial liner assembly 100, according to an embodiment of the present disclosure;
[0015] FIG. 7 illustrates a locking member 3 of the trial liner assembly 100, according to an embodiment of the present disclosure;
[0016] FIG. 8 illustrates a trial acetabular shell 4, according to an embodiment of the present disclosure;
[0017] FIG. 9 illustrates an implant acetabular shell 5, according to an embodiment of the present disclosure;
[0018] FIG. 10 illustrates a cross-section view of the trial liner assembly 100, according to an embodiment of the present disclosure;
[0019] FIG. 11 illustrates a disassembled view of the trial acetabular shell 4 with the trial liner assembly 100, according to an embodiment of the present disclosure;
[0020] FIG. 12 illustrates a disassembled view of the implant acetabular shell 5 with the trial liner assembly 100, according to an embodiment of the present disclosure;
[0021] FIG. 13 illustrates an assembled view of the trial acetabular shell 4 with the trial liner assembly 100, according to an embodiment of the present disclosure;
[0022] FIG. 14 illustrates an assembled view of the implant acetabular shell 5 with the trial liner assembly 100, according to an embodiment of the present disclosure;
[0023] FIG. 15 illustrates a cross sectional assembled view of the implant acetabular shell 5 with the trial liner assembly 100, according to an embodiment of the present disclosure; and
[0024] FIG. 16 illustrates a cross sectional assembled view of the trial acetabular shell 4 with the trial liner assembly 100, according to an embodiment of the present disclosure.
DETAILED DESCRIPTION OF THE ACCOMPANYING DRAWINGS
[0025] Prior to describing the disclosure in detail, definitions of certain words or phrases used throughout this patent document will be defined: the terms "include" and "comprise", as well as derivatives thereof, mean inclusion without limitation; the term "or" is inclusive, meaning and/or; the phrases "coupled with" and "associated therewith", as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have a property of, or the like. Definitions of certain words and phrases are provided throughout this patent document, and those of ordinary skill in the art will understand that such definitions apply in many, if not most, instances to prior as well as future uses of such defined words and phrases.
[0026] Reference throughout this specification to “one embodiment,” “an embodiment,” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrases “in one embodiment,” “in an embodiment,” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment, but mean “one or more but not all embodiments” unless expressly specified otherwise. The terms “including,” “comprising,” “having,” and variations thereof mean “including but not limited to” unless expressly specified otherwise. An enumerated listing of items does not imply that any or all of the items are mutually exclusive and/or mutually inclusive, unless expressly specified otherwise. The terms “a,” “an,” and “the” also refer to “one or more” unless expressly specified otherwise.
[0027] Although the operations of exemplary embodiments of the disclosed method may be described in a particular, sequential order for convenient presentation, it should be understood that the disclosed embodiments can encompass an order of operations other than the particular, sequential order disclosed. For example, operations described sequentially may in some cases be rearranged or performed concurrently. Further, descriptions and disclosures provided in association with one particular embodiment are not limited to that embodiment, and may be applied to any embodiment disclosed herein. Moreover, for the sake of simplicity, the attached figures may not show the various ways in which the disclosed system, method, and apparatus can be used in combination with other systems, methods, and apparatuses.
[0028] Furthermore, the described features, advantages, and characteristics of the embodiments may be combined in any suitable manner. One skilled in the relevant art will recognize that the embodiments may be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments. These features and advantages of the embodiments will become more fully apparent from the following description and apportioned claims, or may be learned by the practice of embodiments as set forth hereinafter.
[0029] The present disclosure relates to a hip prosthetic system having a hip prosthetic device (or interchangeably referred to as a hip prosthesis) and a trial liner assembly. The trial liner assembly is used to assess fit, alignment, and stability of a hip prosthesis before selecting and implanting the hip prosthesis permanently. A hip prosthesis typically includes an acetabular shell, a liner, a femoral head, and a femoral stem. The acetabular shell is implanted in a patient’s acetabulum and provides a stable foundation, replacing a damaged socket of a hip joint. The liner is inserted in the acetabular shell to serve a smooth bearing surface for the femoral head. The femoral head may be a ball-shaped part of the hip joint which articulates with the acetabular shell, thereby facilitating hip movement. The femoral stem is an elongated component that is inserted into a femur to provide stability and support for the femoral head. The trial liner assembly is inserted within the acetabular shell during a surgical procedure. The trial liner assembly allows medical practitioners to accurately evaluate and optimize a fit, alignment, and performance of hip implant components before final implantation. According to an embodiment, the trial liner assembly includes a trial liner, a fastener and a locking member. The fastener is removably disposed with the trial liner and is configured to detachably couple the trial liner with an acetabular shell (e.g., at least one of a trial acetabular shell or an implant acetabular shell). In an embodiment, the fastener enables coupling the trial liner with both the trial acetabular shell and the implant acetabular shell so that the alignment of an implant liner can be tested with the implant acetabular shell more accurately and efficiently. The locking member is configured to lock the fastener at a position and prevent the displacement of the fastener in the proximal direction.
[0030] FIG. 1 illustrates a cross section view of a trial liner assembly 100, according to an embodiment of the present disclosure. FIG. 2 illustrates a top view of the trial liner assembly 100, according to an embodiment of the present disclosure. FIG. 3 illustrates a front view of the trial liner assembly 100, according to an embodiment of the present disclosure. The trial liner assembly 100 has a proximal end 100a and a distal end 100b. The trial liner assembly 100 includes a trial liner 1 (hereinafter referred to as liner 1), a fastener 2 and a locking member 3, according to an embodiment. The fastener 2 is configured to detachably couple the liner 1 with an acetabular shell (either a trial acetabular shell or an acetabular shell of a hip prosthesis) as explained later. The locking member 3 is disposed within the liner 1 and is configured to securely hold the fastener 2 at a desired position within the liner 1.
[0031] The trial liner assembly 100 is used in a preoperative assessment phase of a hip replacement surgery. The trial liner assembly 100 is a temporary component used by medical practitioners to assess fit, alignment, and stability before selecting and implanting a permanent implant. The medical practitioners may use the trial liner assembly 100 to simulate a placement of the final implant within a hip joint of a patient.
[0032] An acetabular component of a hip prosthetic device is used in the hip replacement surgeries to replace a damaged or deteriorated acetabulum, which may be a socket-shaped part of a hip joint. The acetabular component includes an acetabular shell. The acetabular shell forms an outer part of the acetabular component and may be made of a metal or ceramic material. The acetabular shell is designed to fit securely within a patient's acetabulum thereby providing stability and support for the hip joint. The trial liner assembly 100 is inserted inside the acetabular shell to assess a fit and alignment of the liner 1 with respect to the acetabular shell.
[0033] Referring to FIGS. 4 – 5, the liner 1 is designed to mimic the shape, size and contours of a liner to be used with the hip prosthesis. It should be noted that inner structures of the liner 1 are shown in FIG. 4 by dotted lines for better clarity only. The liner 1 is configured to fit within an acetabular shell (a trial acetabular shell and/or an implant acetabular shell) and has a shape generally corresponding to the shape of the acetabular shell. In an embodiment, the liner 1 is cup-shaped. The liner 1 has a proximal end 101a and a distal end 101b. The liner 1 includes a bearing portion 1e disposed in an inner surface of the liner 1. The bearing portion 1e has a concave profile. The bearing portion 1e is configured to receive a femoral head (not shown) of the hip prosthetic device. The femoral head is a ball-shaped part of the hip prosthetic device. The bearing portion 1e has a shape and dimensions corresponding to the shape and dimensions of a distal portion of the femoral head. In the depicted embodiment, the bearing portion 1e is semi-spherical. The liner 1 includes a first channel 1f provided axially and extending from a distal end of the bearing portion 1e towards the distal end 101b of the liner 1. According to an embodiment, the first channel 1f is generally cylindrical. The first channel 1f has a bottom face 1d. The liner 1 includes a second channel 1g extending from a distal end of the first channel 1f to the distal end 101b. The second channel 1g is cylindrical and has a diameter smaller than the diameter of the first channel 1f. According to an embodiment, the first channel 1f is configured to seat down the femoral head and the second channel 1g is configured to get a desired offset value between the liner 1 and the acetabular shell. The second channel 1g may also be used for resting the liner 1 on the surface of the acetabular shell. Therefore, the first channel 1f and the second channel 1g enable a user to achieve the desired offset value which will help the user to choose the correct liner size and prevent misalignment.
[0034] The liner 1 has a groove 1c formed along an inner peripheral surface of the first channel 1f and provided proximally to the bottom face 1d. The groove 1c is configured to receive the locking member 3. The groove 1c may be a channel or a recessed area that runs around a circumference of the first channel 1f of the liner 1. The groove 1c helps in securely holding the locking member 3 in place within the liner 1 during the operation of the trial liner assembly 100.
[0035] In an embodiment, the liner 1 includes a rim 1b disposed on an outer surface of the liner 1 towards the distal end 101b and a plurality of tabs 1a disposed circumferentially on the outer surface of the liner 1 towards the proximal end 101a. The plurality of tabs 1a may be uniformly or non-uniformly distributed. In the depicted embodiment, the liner 1 includes four tabs distributed evenly.
[0036] The liner 1 can be made of a material such as, without limitation, polypropylene, polyphenylsulfone (PPSU), medical grade acetal copolymer or any other biocompatible material. In an example implementation, the liner 1 is made of medical grade acetal copolymer.
[0037] FIG. 6 illustrates the fastener 2 of the trial liner assembly 100, according to an embodiment of the present disclosure. In an embodiment, the fastener 2 is removably disposed within the liner 1 such that at least a portion of the fastener 2 resides between the bottom face 1d and the locking member 3 and at least a mating portion of the fastener 2 used for coupling the liner 1 with the acetabular shell extends out of the liner 1. The fastener 2 has a proximal end 201a and a distal end 201b. In an embodiment, the fastener 2 includes a head portion 2a disposed towards the proximal end 201a and a first mating portion 2b extended outwardly from the head portion 2a towards the distal end 201b. The head portion 2a includes a groove on a top surface of the head portion 2a. A slot 2c is provided centrally in the groove and extends from the proximal end 201a to at least partially into the first mating portion 2b. The slot 2c enables the user to grasp the fastener 2 while inserting the fastener 2 into the liner 1 and fastening the fastener 2 with the acetabular shell. The first mating portion 2b is configured to mate a corresponding mating portion of the acetabular shell as explained later. The first mating portion 2b can be threaded, semi-threaded or smooth. In the depicted embodiment, the first mating portion 2b has threads along a partial length of the first mating portion 2b from the distal end 201b. The threads are provided along periphery of the first mating portion 2b. The threads of the first mating portion 2b allow a rotational motion thereby, enabling the fastener 2 to be twisted or turned to fasten or unfasten.
[0038] In an embodiment, the fastener 2 is inserted into the liner 1. When the fastener 2 is disposed within the liner 1, a bottom face (not shown) of the head portion 2a contacts the bottom face 1d. The first mating portion 2b is disposed into the second channel 1g of the liner 1 such that at least a portion of the first mating portion 2b (e.g., the threads) extends out of the liner 1 from the distal end 101b of the liner 1 (as depicted in Fig. 10). The diameter of the first mating portion 2b corresponds to the diameter of the second channel 1g and the diameter of the head portion 2a corresponds to the outer diameter of the bottom face 1d.
[0039] The fastener 2 can be made of a material such as, without limitation, stainless steel, titanium, cobalt chromium, or any other biocompatible material. In an example implementation, the fastener 2 is made of grade 17-4 stainless steel.
[0040] FIG. 7 illustrates the locking member 3 of the trial liner assembly 100, according to an embodiment of the present disclosure. The locking member 3 is configured to be removably disposed within the first channel 1f. In an embodiment, the locking member 3 is configured to be removably disposed within the groove 1c of the liner 1. The locking member 3 is configured to prevent displacement of the fastener 2 in the proximal direction once the fastener 2 is inserted into the liner 1. In the illustrated embodiment, the locking member 3 is in the form of a ring having a circular or an oval shaped profile. The locking member 3 may have specific dimensions that conform with the contours of the groove 1c present within the first channel 1f of the liner 1. The locking member 3 fits within the groove 1c such that the locking member 3 does not displace or dislodge from the groove 1c. The locking member 3 includes protruded portions 3a and a cut out portion 3b. The protruded portions 3a are provided on either side of the cut out portion 3b. The protruded portions 3a have a width greater than the width of remaining portion of the locking member 3. As a result, the locking member 3 prevents any displacement of the fastener 2 in the proximal direction once the fastener 2 is inserted into the liner 1. In other words, the locking member 3 functions as a stopper. According to an embodiment, the cutout portion 3b is used for assembling the locking member 3 with the liner 1. Each of the protruded portions 3a includes a hole 3c. The holes 3c enable the user to grip the locking member 3 by a gripping tool (e.g., pliers) and insert the locking member 3 into the liner 1. For example, the user can grip the locking member 3 by inserting the pliers inside the holes 3c and insert the locking member 3 into the liner 1. Once the locking member 3 is disposed within the groove 1c, the locking member 3 may expand inside and help in alignment of the fastener 2 with the liner 1. The locking member 3 can be made of a material such as, without limitation, stainless steel, titanium, cobalt chromium or any other biocompatible material. In an embodiment, the locking member 3 is made of stainless steel.
[0041] Upon inserting the fastener 2 into the liner 1, the locking member 3 is inserted into the liner 1 and disposed within the groove 1c. A bottom face of the locking member 3 mates with the top surface of the head portion 2a of the fastener 2 such that the head portion 2a resides between the locking member 3 and the bottom face 1d of the liner 1. Thus, the locking member 3 secures the fastener 2 within the liner 1 and prevents the fastener 2 from moving or dislodging during the use of the trial liner assembly 100. Therefore, the trial liner assembly 100 remains properly aligned and functional during the preoperative assessment phase of the hip replacement surgery.
[0042] FIG. 8 illustrates a trial acetabular shell 4, according to an embodiment of the present disclosure. The trial acetabular shell 4 is an acetabular shell component temporarily utilized during the preoperative assessment phase to evaluate fit and alignment with the liner 1 using the trial liner assembly 100. The trial acetabular shell 4 is designed to mimic shape, size and contour of an acetabular shell to be used in the final hip prosthesis (hereinafter, referred to as an implant acetabular shell). One embodiment of such an acetabular shell is an implant acetabular shell 5 (depicted in FIG. 9).
[0043] The trial acetabular shell 4 has a proximal end 401a and a distal end 401b. In an embodiment, the trial acetabular shell 4 includes a receiving portion 4b configured to receive the liner 1. The receiving portion 4b has a concave profile generally matching an outer profile of the liner 1. The outer surface of the liner 1 has a convex profile and is configured to rest with the receiving portion 4b. The receiving portion 4b has a second mating portion 4c (depicted in Fig. 16) provided at the distal end 401b. The second mating portion 4c is configured to mate with the first mating portion 2b of the fastener 2. In an embodiment, the second mating portion 4c includes threads that are complementary to the threads of the first mating portion 2b. In the illustrated embodiment, the threads of the first mating portion 2b are male threads and the threads on the second mating portion 4c are female threads. The trial acetabular shell 4 includes a top surface 4a and an outer surface 4d. The trial acetabular shell 4 is suitably dimensioned and is made of any suitable biocompatible material.
[0044] The trial acetabular shell 4 is coupled with the liner 1 to evaluate the fit and alignment of the implant liner with the implant acetabular shell 5. FIG. 11 illustrates a disassembled view of the trial acetabular shell 4 with the trial liner assembly 100, according to an embodiment of the present disclosure. The trial liner assembly 100 is aligned with the trial acetabular shell 4 as shown in Fig. 11. The trial liner assembly 100 is then inserted into the trial acetabular shell 4 and assembled with the trial acetabular shell 4 as shown in Fig. 13. Bottom surfaces of the plurality of tabs 1a contact the top surface 4a of the trial acetabular shell 4 and the receiving portion 4b contacts the outer surface of the liner 1. The fastener 2 is then rotated. When the fastener 2 is twisted into place, the first mating portion 2b and the second mating portion 4c interlock with each other thereby creating a secure attachment between the trial liner assembly 100 and the trial acetabular shell 4. For example, the threads of the second mating portion 4c engage with the threads of the first mating portion 2b, thereby coupling the trial liner assembly 100 with the trial acetabular shell 4 as depicted in Fig. 16. In an embodiment, the trial liner assembly 100 is temporarily coupled within the trial acetabular shell 4 to assess the fit and alignment of the prosthetic device. The fastener 2 detachably couples the trial liner assembly 100 with the trial acetabular shell 4. The liner 1 interfaces with the trial acetabular shell 4. Since the liner 1 and the trial acetabular shell 4 generally mimic the implant liner and the implant acetabular shell 5, respectively, a size of the implant liner which may fit with the implant acetabular shell 5 may be gauged from the fitment of the liner 1 within the trial acetabular shell 4. If there is a misalignment, that means that the implant liner would not fit the implant acetabular shell 5 and that another size of the implant liner may need to be used.
[0045] FIG. 9 illustrates an implant acetabular shell 5, according to an embodiment of the present disclosure. The implant acetabular shell 5 is implanted in a patient’s acetabulum during the implantation procedure. The implant acetabular shell 5 is made of a suitable biocompatible material and has a desired shape and suitable dimensions as per requirements based upon, for example, the patient’s anatomy. The implant acetabular shell 5 has a proximal end 501a and a distal end 501b. The implant acetabular shell 5 includes a receiving portion configured to receive the liner 1. The receiving portion of the implant acetabular shell 5 has a concave profile generally matching an outer profile of the liner 1. The implant acetabular shell 5 has a third mating portion 5c (depicted in Fig. 15) disposed centrally at the distal end 501b. The third mating portion 5c is configured to mate with the first mating portion 2b of the fastener 2. In an embodiment, the third mating portion 5c includes threads that are complementary to the threads of the first mating portion 2b. In the illustrated embodiment, the threads of the first mating portion 2b are male threads and the threads of the third mating portion 5c are female threads. The implant acetabular shell 5 includes a plurality of recesses 5b provided circumferentially on an inner surface of the implant acetabular shell 5 towards the proximal end 501a. The plurality of recesses 5b are configured to receive the plurality of tabs 1a. The implant acetabular shell 5 has an outer surface 5d configured to fit in the patient’s acetabulum.
[0046] The implant acetabular shell 5 is coupled with the liner 1 to evaluate the fit and alignment of the implant liner with the implant acetabular shell 5. For example, since the liner 1 mimics the implant liner, the user can assess the expected alignment of the implant liner with the implant acetabular shell 5 based upon the fitment of the liner 1 with the implant acetabular shell 5. When there is a perfect fit, it helps the user to determine that the implant liner and the implant acetabular shell 5 would also perfectly fit with each other. Further, when there is any misalignment, the user can determine that the implant liner and the implant acetabular shell 5 would not fit and consequently, the user can choose a different implant liner. Thus, the trial liner assembly 100 enables the user to test the alignment and fit of the implant liner with the implant acetabular shell 5 during the preoperative phase itself and allows the user to decide a correct size of the implant liner and the implant acetabular shell before the actual implantation. As a result, the chances of revision surgeries become negligible.
[0047] FIG. 12 illustrates a disassembled view of the implant acetabular shell 5 with the trial liner assembly 100, according to an embodiment of the present disclosure. The trial liner assembly 100 is aligned with the implant acetabular shell 5 as shown in Fig. 12. The trial liner assembly 100 is then inserted into the implant acetabular shell 5 and assembled with the implant acetabular shell 5 as shown in Fig. 14. The plurality of tabs 1a fit within the plurality of recesses 5b. Further, the receiving portion of the implant acetabular shell 5 contacts the outer surface of the liner 1 and the rim 1b rests on an inner surface 5a (as shown in FIG. 9) of the receiving portion of the implant acetabular shell 5. The outer surface of the liner 1 rests within the receiving portion of the implant acetabular shell 5. The fastener 2 is then rotated. When the fastener 2 is twisted into place, the first mating portion 2b and the third mating portion 5c interlock with each other thereby creating a secure attachment between the trial liner assembly 100 and the implant acetabular shell 5. For example, the threads of the third mating portion 5c engage with the threads of the first mating portion 2b, thereby coupling the trial liner assembly 100 with the implant acetabular shell 5 as depicted in Fig. 15.
[0048] Though the coupling of the fastener 2 with the trial acetabular shell 4 and the implant acetabular shell 5 has been explained herein using a threaded coupling mechanism, it should be understood that other suitable coupling techniques such as, snap fit mechanism, friction fit mechanism, etc. can be used and it will be apparent to a person skilled in the art that the first mating portion 2b, the second mating portion 4c and third mating portion 5c are designed accordingly.
[0049] Thus, the trial liner assembly 100 allows the user to test the fitment of the implant acetabular shell 5 with the implant liner with the help of the liner 1, the trial acetabular shell 4 and the implant acetabular shell 5 and select an appropriate size of the implant liner for a perfect fit. This presents several advantages. Advantageously, the present disclosure ensures a precise alignment and compatibility between the trial liner assembly 100 and the acetabular shell thereby minimizing a risk of mismatch between an implant during the hip replacement surgery that could lead to post-surgical complications. The present disclosure also enhances an accuracy of preoperative assessments thereby enabling surgeons to make informed decisions about an implant selection and placement. Additionally, the usage of the trial liner assembly 100 reduces a likelihood of delays and inconvenience during a surgery. Furthermore, an enhanced compatibility of the trial liner assembly 100 with the acetabular shell mitigates a risk of instability, dislocation, and impingement post-surgery thereby promoting better patient outcomes and minimizing a need for additional interventions.
[0050] The scope of the invention is only limited by the appended patent claims. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary and that the actual parameters, dimensions, materials, and/or configurations will depend upon the specific application or applications for which the teachings of the present invention is/are used. , Claims:We Claim:
1. A trial liner assembly (100) comprising:
a trial liner (1) comprising a bearing portion (1e) on an inner surface and a first channel (1f) extended distally from a center of the bearing portion (1e), the first channel (1f) comprising a bottom face (1d);
a fastener (2) removably disposed within the trial liner (1) and configured to detachably couple the trial liner (1) with at least one of a trial acetabular shell (4) or an implant acetabular shell (5); and
a locking member (3) removably disposed in the first channel (1f) and configured to prevent displacement of the fastener (2) in the proximal direction;
wherein at least a portion of the fastener (2) resides between the locking member (3) and the bottom face (1d).
2. The trial liner assembly (100) as claimed in claim 1, wherein the fastener (2) comprises a head portion (2a) and a first mating portion (2b) extended distally from the head portion (2a), the first mating portion (2b) is configured to mate with at least one of: a second mating portion (4c) of the trial acetabular shell (4) and a third mating portion (5c) of the implant acetabular shell (5), wherein, a top surface of the head portion (2a) contacts a bottom surface of the locking member (3) and a bottom face of the head portion (2a) contacts the bottom face (1d) of the trial liner (1) and at least a portion of the first mating portion (2b) extends out of the trial liner (1) from a distal end (101b) of the trial liner (1).
3. The trial liner assembly (100) as claimed in claim 2, wherein the first mating portion (2b) comprises threads provided along periphery of the first mating portion (2b) for at least a partial length of the first mating portion (2b) from a distal end (201b) of the fastener (2).
4. The trial liner assembly (100) as claimed in claim 2, wherein the fastener (2) comprises a groove on the top surface of the head portion (2a) and a slot (2c) provided centrally in the groove and extending at least partially into the first mating portion (2b).
5. The trial liner assembly (100) as claimed in claim 1, wherein the bearing portion (1e) has a concave profile.
6. The trial liner assembly (100) as claimed in claim 1, wherein the liner (1) includes an outer surface having a convex profile configured to rest within a receiving portion (4b) of the trial acetabular shell (4) or a receiving portion of the implant acetabular shell (5).
7. The trial liner assembly (100) as claimed in claim 1, wherein the liner (1) includes a plurality of tabs (1a) provided circumferentially on an outer surface of the trial liner (1) towards a proximal end (101a) of the trial liner (1), the plurality of tabs (1a) configured to fit within a plurality of recesses (5b) of an implant acetabular shell (5).
8. The trial liner assembly (100) as claimed in claim 1, wherein the trial liner (1) comprises a rim (1b) disposed on an outer surface of the trial liner (1) towards a distal end (101b) of the trial liner (1) and configured to rest on an inner surface (5a) of the receiving portion of the implant acetabular shell (5).
9. The trial liner assembly (100) as claimed in claim 1, wherein the liner (1) comprises a second channel (1g) extending from a distal end of the first channel (1f) to a distal end (101b) of the liner (1), the second channel (1g) having the diameter smaller than the diameter of the first channel (1f).
10. The trial liner assembly (100) as claimed in claim 1, wherein the locking member (3) is configured to be removably disposed within a groove (1c) provided in the first channel (1f) proximal to the bottom face (1d).
11. The trial liner assembly (100) as claimed in claim 10, wherein the locking member (3) comprises a cut out portion (3b) and protruded portions (3a) provided on either side of the cut out portion (3b) and having a width greater than a width of remaining portion of the locking member (3).