Surgical kit and method
The surgical kit and method provide a precise mechanism for femoral neck resection during hip replacement, addressing inaccuracies in conventional procedures by using a mounting portion and resection guide to ensure correct implant seating and leg length restoration.
Patent Information
- Application Number
- JP2025168198
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2019-03-27
- Filing Date
- 2025-10-06
- Publication Date
- 2025-12-11
AI Technical Summary
Conventional hip replacement procedures face challenges in accurately resecting the femoral neck, leading to potential inaccuracies in implant seating and leg length, which can impact the outcome of the surgery.
A surgical kit and method utilizing a mounting portion with guide holes for inserting pins into the femoral head, a body portion attachable to an intramedullary pin, and a resection guide with corresponding guide holes to indicate the correct resection plane, ensuring precise neck resection and restoration of leg length.
The kit and method enable controlled and accurate resection of the femoral neck, improving the seating position of the implant and restoring leg length by providing a precise reference and adjustment mechanism.
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Figure 2025182065000001_ABST
Abstract
Description
[Technical Field]
[0001] The present invention relates to a surgical kit and method for performing controlled resection of the neck of the femur during a hip replacement procedure. [Background technology]
[0002] Hip replacement is a surgical procedure in which the hip joint is replaced with an artificial joint implant. A total hip replacement involves placing an acetabular cup implant in the patient's acetabulum and another implant in the patient's femur. In a partial hip replacement, an implant is placed in the patient's femur, but no acetabular cup is placed in the acetabulum. In either type of procedure, the implant placed in the femur typically includes a stem that is received in the intramedullary canal and a head that has a bearing surface that is received in the acetabulum or acetabular cup implant. The implant also typically includes a neck that extends between the proximal end of the stem and the head.
[0003] In a conventional procedure, the neck of the femur is first resected to place the implant into the intramedullary canal. Resection of the femoral neck provides access to the canal, which can then be prepared to receive the stem of the implant using a broach and reamer. During a hip replacement procedure, restoring leg length is generally the result of good planning and experience and can generally be controlled by preoperative planning. The neck resection can generally be a freehand cut. Once the stem is placed in the canal, the seating position of the implant can generally depend on the location of the cut. If the cut is not positioned correctly, this can result in an inaccurate seating position of the implant. This can result in a negative impact on the leg length of the femur due to implantation.
[0004] U.S. Patent No. 6,503,255 (B1) describes a cutting guide instrument and method for enabling high-precision resection of the head of the neck of a human femur at a predetermined cutting angle relative to the femoral shaft and at a predetermined cutting level relative to the proximal end of the head. A support portion is fixed to the femur during resection. A longitudinal guide carrier is supported by the support portion and aligned along the femoral neck at the predetermined cutting angle relative to the femoral shaft. A cutting guide is supported by the guide carrier and is movable along the axis of the guide carrier to a cutting position corresponding to the predetermined cutting level.
[0005] WO 2002 / 026145 A1 describes a guide instrument for resecting the femoral neck in the context of a total hip arthroplasty, the guide instrument comprising an instrument body with means for receiving a shank or the like mounted in the medullary canal of the femoral neck, the shank having a longitudinal central axis, the instrument body comprising guide means displaceable along the shank and having a leading arrangement for means for performing the femoral neck cut, and at least a rotary ruler attached to the instrument body, the rotary ruler intended to cooperate with the existing femoral head of the femur.
[0006] U.S. Patent No. 5,578,037(A) describes a surgical resection guide that allows a surgeon to resect the femoral neck during a hip arthroplasty procedure, thereby allowing a femoral prosthesis to be implanted within the patient and preserving or closely approximating the anatomical center of rotation of the hip joint. The guide can be used for left or right hip arthroplasty procedures using either an anterior or posterior surgical approach.
[0007] U.S. Patent No. 8,246,621 (B2) describes an instrument kit provided for reaming bone around a head of a bone, the bone including an implanted epiphyseal component. The instrument kit includes a reaming guide and a reamer. The reaming guide is connectable to the epiphyseal component and has a first reamer support feature and a second reamer support feature. The reamer is connectable to one of the first reamer support feature and the second support feature to ream the bone around the epiphyseal component.
[0008] U.S. Patent No. 7,601,155 (B2) describes an intramedullary femoral broach that aligns two instruments. A femoral neck resection guide slides over the broach and centers it on the patient's femoral head to determine the height and angular rotation of the resection. Circular rings on the head and cutting arm ensure the system fits any femur. A template is applied to the femoral broach and locks into place by seating itself against the broach's buttress. The broach is then reinserted into the intramedullary canal. When the template reaches the greater trochanter, the sizer is adjusted to rotate the canal anteversion. The handle of the femoral broach is struck with a mallet until the template is embedded in the intramedullary bone proximal to the femoral neck. A retractor facilitates reaming of the acetabulum through a small anterior incision. The proximal portion bites into the superior acetabular bone, allowing for soft tissue retraction.
[0009] U.S. Patent No. 4,959,066(A) describes an osteotomy guide assembly for femoral neck osteotomy that includes a saddle locator assembly and a saw guide mount. The saddle locator assembly includes a syringe barrel-shaped locating device for locating the saddle region of the proximal femur. The syringe barrel further includes a transverse support bar extending from the syringe barrel. The syringe barrel is temporarily positioned within the medullary canal of the femur and positioned over the intramedullary diaphysis extending from the medullary canal of the femur. A saw guide is used in conjunction with the saddle locator assembly. The saw guide is attached to the support bar by a single locking mechanism that provides two-way positional adjustment of the saw guide relative to the support bar, including anterior-posterior adjustment along the transverse support bar and axially along the femur via a post extending from the saw guide.
[0010] U.S. Patent No. 7,833,275 (B2) describes methods and equipment for performing minimally invasive total hip replacement surgery. An approximately 3.75-5 centimeter (1.5-2 inch) anterior incision is made along the femoral neck. The femoral neck is severed from the femoral shaft and removed through the anterior incision. The acetabulum is prepared to receive an acetabular cup through the anterior incision, and the acetabular cup is placed within the acetabulum through the anterior incision. A approximately 2-3 centimeter (0.8-1.2 inch) posterior incision is made generally aligned with the axis of the femoral shaft to provide access to the femoral shaft. Preparation of the femoral shaft, including reaming and filing, is performed through the posterior incision, and a femoral stem is inserted through the posterior incision and implanted into the femur. A total hip replacement is performed utilizing various novel instruments including an osteotomy guide, an awl for positioning a posterior incision aligned with the axis of the femoral shaft, a tubular posterior retractor, a selectively lockable file handle with an engagement guide, and a selectively lockable temporary neck.
[0011] U.S. Patent No. 5,607,431(A) describes a surgical instrument system for preparing the medullary canal of a femur for implantation of a prosthetic femoral component, which includes a template used to determine the osteotomy location from an x-ray. A gauge is provided for locating and marking this location on the anterior femur. A distal reamer with an elongated drive shaft is used to prepare the canal to receive the distal stem of the femoral component. A metaphyseal template is used to determine the appropriate anteversion / retroversion, and a chisel is used to cut the lateral region of the femur, both guided by the elongated reamer shaft. A proximal broach, also guided by the reamer shaft, is used to shape the proximal medullary canal.
[0012] U.S. Patent No. 7,582,091 (B2) discloses an osteotomy guide for indicating a femoral neck resection on a femur and a method for using the same. The osteotomy guide includes a feature indexing for aligning the guide with a landmark, and a resection guide for indicating the resection relative to the feature indexing.
[0013] U.S. Patent No. 4,621,630(A) describes a femoral neck osteotomy guide comprising a longitudinal rod having a mounting structure at its lower end for securing the rod to the femur at the greater trochanter. A laterally extending support arm is secured to the rod adjacent its lower end, and a guide bar is connected to the support arm. The guide bar has at least one elongated planar surface disposed at a 45° angle relative to the axis of the rod. During use, the rod is aligned with the longitudinal centerline of the femur and attached to the femur at the greater trochanter. The rod is manipulated until the support arm and the longitudinal centerline of the tibia are positioned in the same plane. In this procedure, the elongated planar surface of the guide bar is properly positioned so that an instrument engaging with that surface traverses the femoral neck at a 45° angle relative to the longitudinal centerline of the femur. Summary of the Invention [Means for solving the problem]
[0014] Aspects of the invention are set out in the accompanying independent and dependent claims. Combinations of features from the dependent claims may be combined with features of the independent claims as appropriate and not merely as explicitly set out in the claims.
[0015] According to an aspect of the present invention, there is provided a surgical kit for performing controlled resection of the neck of a femur during a hip replacement procedure, the surgical kit comprising: a mounting portion including at least two guide holes for inserting guide pins into the femoral head while the mounting portion is positioned on the anterior aspect of the femoral head; a body portion connected to the mounting portion, the body portion including an opening for mounting the body portion over an intramedullary pin located in the intramedullary canal of the femur; a resection guide including at least two guide holes having the same arrangement as the guide holes of the mounting portion so as to enable the resection guide to be mounted on the anterior side of the femoral head with the guide pin inserted into the femoral head to position the resection plane indicator of the resection guide relative to the neck of the femur.
[0016] Kits according to embodiments of the present invention can assist in indicating the correct location of the neck resection plane to restore leg length in a hip replacement procedure. Embodiments of the present invention accomplish this by providing a body portion that can be mounted on the femur using an intramedullary pin (such as a starter rod or reamer) positioned in the intramedullary canal of the femur to create an extramedullary reference relative to the intramedullary axis, a mounting portion that can be used to reference the femoral head center while inserting the guide pin into the femoral head, and a resection guide with corresponding guide holes for mounting the resection guide on the guide pin so that the correct resection plane is indicated on the neck of the femur in position relative to the femoral head center.
[0017] The resection plane indicator can, for example, indicate the location of two resection planes, which can allow a neck resection using two angled cuts to be performed. The two resection planes can be oriented at angles of approximately 127°, 129°, or 135° relative to each other.
[0018] The resection plane indicator may comprise a guide slot or a guide surface.
[0019] The guide slot or guide surface may be a cutting slot or cutting guide surface for receiving a blade of a cutting device during resection of the neck.
[0020] The resection guide can include multiple sets of guide holes, each set including at least two guide holes having the same arrangement as the guide holes in the mounting portion, and the multiple sets of guide holes can be positioned within the resection guide such that mounting the resection guide on the anterior aspect of the femoral head with a guide pin inserted into one of the sets of guide holes allows adjustment of the position of the resection plane indicator relative to the neck of the femur.
[0021] The mounting portion may include three guide holes, which may provide additional stability / precision for the attachment of the mounting portion and subsequent resection guide.
[0022] The guide holes on the mounting part are a central guide hole for aligning the attachment portion with the center of the femoral head when the attachment portion is positioned on the anterior aspect of the femoral head; an outer guide hole located on a first side of the central guide hole; and an inner guide hole located on a second side opposite the first side of the central guide hole.
[0023] The surgical kit may further include a plurality of guide pins.
[0024] The opening for mounting the body portion onto the intramedullary pin may be adjustably positionable within the body portion according to the femoral offset of the femur.
[0025] The body portion can include markings for reading the femoral offset of the femur according to the location of the opening for mounting the body portion onto the intramedullary pin while the mounting portion is mounted on the femoral head, and the read femoral offset value can be used to determine the type of neck / head combination to be used in the implant to restore the femoral offset.
[0026] The kit can include multiple resection guides, each of a different shape and / or size according to a respective implant geometry for positioning the resection plane indicator of the selected resection guide relative to the neck of the femur. The implant geometry can include, for example, a standard lateral orientation, a short neck, and / or a coxa vara geometry.
[0027] The mounting portion may include a substantially circular femoral head contacting surface.
[0028] The mounting portion may be referred to by those skilled in the art as a spherometer.
[0029] According to another aspect of the present invention, there is provided a method for performing a controlled resection of the neck of a femur during a hip replacement procedure using a surgical kit, the surgical kit comprising: a mounting portion including at least two guide holes for receiving pins; a body portion connected to the mounting portion, the body portion having an opening; a resection guide including at least two guide holes having the same arrangement as the guide holes of the attachment portion; The method is Mounting the body portion onto an intramedullary pin located within the intramedullary canal of the femur by inserting the pin into the opening in the body portion; disposing a mounting portion on the anterior aspect of the femoral head; Inserting a respective guide pin through a respective guide hole in the mounting portion and into the femoral head; Removing the attachment portion from the femoral head; Mounting a resection guide on the anterior aspect of the femoral head with the guide pin inserted into the femoral head to position a resection plane indicator of the resection guide; Use the resection plane indicator Marking the location of the resection plane on the femoral neck, or and guiding a blade of a cutting device to resect the neck of the femur.
[0030] A method according to an embodiment of the present invention can assist in indicating the correct location of the neck resection plane to restore leg length in a hip replacement procedure. Embodiments of the present invention accomplish this by using a body portion that can be attached to the femur using an intramedullary pin (such as a starter rod or reamer) placed in the intramedullary canal of the femur to create an extramedullary reference to the intramedullary axis, using an attachment portion to reference the center of the femoral head while inserting the guide pin into the femoral head, and using a resection guide with corresponding guide holes to attach the resection guide onto the guide pin so that the correct resection plane is indicated on the neck of the femur in position relative to the center of the femoral head.
[0031] The resection guide can include multiple sets of guide holes. Each set of guide holes can include at least two guide holes having the same arrangement as the guide holes in the mounting portion. The multiple sets of guide holes can be positioned within the resection guide so as to allow adjustment of the position of the resection plane indicator relative to the neck of the femur by mounting the resection guide on the anterior aspect of the femoral head with the guide pin inserted into one of the sets of guide holes. selecting a set of guide holes; and mounting a resection guide on the anterior aspect of the femoral head with the guide pins inserted into one set of the guide holes of the selected set of guide holes.
[0032] The method can include adjustably positioning an opening for mounting the body portion onto the intramedullary pin relative to the remainder of the body portion according to a femoral offset of the femur.
[0033] The method may include, while the mounting portion is mounted on the femoral head, reading a femoral offset of the femur according to a position of an opening for mounting the body portion onto the intramedullary pin relative to a remainder of the body portion according to the femoral offset of the femur.
[0034] The method may include using the femoral offset value to determine the femoral offset of a femoral implant to be installed in a hip replacement procedure.
[0035] The kit can include multiple resection guides, each of a different shape and / or size according to a respective implant geometry for positioning a resection plane indicator of the selected resection guide relative to the neck of the femur. The method can further include selecting one of the resection guides and attaching the selected resection guide onto the anterior aspect of the femoral head with the guide pin inserted into the femoral head. The implant geometry can include, for example, a standard lateral orientation, a short neck, and / or a coxa vara geometry.
[0036] The method may include inserting the intramedullary pin into the intramedullary canal of the femur before mounting the body portion onto the intramedullary pin.
[0037] The mounting portion may include a substantially circular femoral head contacting surface.
[0038] The mounting portion may be referred to by those skilled in the art as a spherometer. [Brief explanation of the drawings]
[0039] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which like reference symbols indicate similar elements and in which: [Figure 1A] 1 shows a device mounted on the proximal end of a femur, according to an embodiment of the present invention. [Figure 1B] 1 illustrates a resection guide according to an embodiment of the present invention. [Figure 1C] 1C illustrates the resection guide of FIG. 1B mounted on the proximal end of the femur, in accordance with an embodiment of the present invention. [Figure 2] 1A mounted on a femur and the resection guide of FIG. 1B. (Although FIG. 2 shows both the device of FIG. 1A and the resection guide of FIG. 1B to illustrate the alignment of their respective features with anatomical features of the femur, it will be understood from the description of FIGS. 1A-1C that, for example, the device of FIG. 1A and the resection guide of FIG. 1B are not typically mounted on the femur at the same time.) [Figure 3] 2 shows an anterior view of the mounting portion of the device of FIG. 1 mounted on the anterior aspect of the femoral head. [Figure 4] 2 shows a superior view of a portion of the device of FIG. 1 mounted on a femur. [Figure 5] 1 shows an anterior view of the resection jig mounted on the anterior aspect of the femoral head. DETAILED DESCRIPTION OF THE INVENTION
[0040] Embodiments of the present invention will now be described with reference to the accompanying drawings.
[0041] 1A, 1B, 1C, and 2 illustrate components of a kit 10 for performing controlled resection of the neck of a femur 60 during a hip replacement procedure. As shown, various parts of the kit can be mounted on the femur 60 to define one or more resection planes during a hip replacement procedure.
[0042] The kit 10 includes a mounting portion 310. The mounting portion 310 may be referred to as a spherometer by those skilled in the art. The mounting portion 310 may be mounted on the anterior aspect of the femoral head 62. The mounting portion 310 includes a femur-facing surface. The mounting portion 310 may include a substantially circular femoral head contact surface. The femoral-facing surface may be substantially concave and curved to fit over the femoral head 62. The rim of the femoral-facing surface may be substantially circular to rest against the femoral head 62. In this embodiment, the femoral-facing surface includes a ring 320 that forms a substantially circular femoral head contact surface, which may rest against the femoral head as shown.
[0043] During a hip replacement procedure, the surgeon may attach the mounting portion 310 onto the anterior aspect of the femoral head 62 such that the central axis of the mounting portion 310 (see, for example, the dotted arrow labeled A in FIG. 1A ) is aligned with the femoral head center 312 when the femoral head 62 is viewed from an anterior position. This may generally be accomplished by visual inspection of the anterior aspect of the femur 60 and femoral head 62 while manually positioning the mounting portion 310.
[0044] The mounting portion 310 includes at least two guide holes extending therethrough to allow the guide pins 340, 342, 344 of the kit 10 to be inserted into the femoral head 62 while the mounting portion 310 is positioned on the anterior aspect of the femoral head 62, as shown in FIG. 1A. The distal ends of the guide pins 340, 342, 344 of the kit 10 may be sharpened, fluted, or otherwise configured to facilitate insertion into the femoral head 62.
[0045] In this embodiment, there are three guide holes, but it is contemplated that two of the more than three guide holes may be provided. For example, the central guide hole in this embodiment may be omitted so that only outer and inner guide holes are present. The guide holes in this embodiment are provided in each of the substantially cylindrical members 330, 320, and 334. The substantially cylindrical members 330, 320, and 334 in this embodiment may be connected to the ring 320 such that their positions relative to the ring 320 are fixed.
[0046] The three guide holes in this embodiment include a central guide hole, an outer guide hole located on a first side of the central guide hole, and an inner guide hole located on a second side opposite the first side of the central guide hole. The central guide hole passes through cylinder 330, the outer guide hole passes through cylinder 332, and the inner guide hole passes through cylinder 334. A central guide pin 340 can be inserted into the central guide hole, an outer guide pin 342 can be inserted into the outer guide hole, and an inner guide pin 344 can be inserted into the inner guide hole.
[0047] The central guide hole extends along the central axis of the mounting portion 310 so that, when the mounting portion 310 is mounted on the anterior aspect of the femoral head 62, as described above, the central guide pin 340 can be inserted into the femoral head 62 along the central axis of the mounting portion 310. Thus, when the central guide pin is inserted, it projects directly into the femoral head central portion 312. Similarly, when the mounting portion 310 is mounted on the anterior aspect of the femoral head 62, as described above, the lateral guide pin 342 and the medial guide pin 344 can be inserted into the femoral head 62 through their respective guide holes. The long axes of the guide holes are generally parallel to one another so that the resection guide 200 of the kit 10 can later be mounted on the guide pins, as described in more detail below.
[0048] The kit 10 may also include a body portion 20 connected to a mounting portion 310. The body portion may assist in correct positioning of the mounting portion 310 on the femoral head 62 and may also allow measurements of femoral offset to be taken. Further details regarding the body portion 20 are provided below.
[0049] Once the guide pins 340 , 342 , 344 are inserted into the femoral head 62 , the mounting portion 310 (and body portion 20 ) may be removed from the femur 60 .
[0050] Kit 10 also includes a resection guide 200 (see FIG. 1B), which is a separate component of kit 10 that can be used to indicate the location of one or more resection planes.
[0051] Resection guide 200 includes at least two guide holes 210. The guide holes 210 of resection guide 200 have the same arrangement as the guide holes of mounting portion 310. This can allow resection guide 200 to be mounted onto guide pins (in this embodiment, guide pins 340, 342, 344) inserted into the femoral head using mounting portion 310, as shown in FIG. 5. Thus, resection guide 200 can be mounted in place on the anterior aspect of femoral head 62 relative to femoral head center portion 312 using guide pins 340, 342, 344 (see FIG. 1C).
[0052] In this embodiment, resection guide 200 includes multiple sets of guide holes 210A, 210B, and 210C. Each set of guide holes 210A, 210B, and 210C has a plurality of guide holes with an arrangement that matches the arrangement of the guide holes in mounting portion 310, as described above, allowing resection guide 200 to be mounted on a guide pin. The purpose of these sets of guide holes 210A, 210B, and 210C is explained below. However, it is contemplated that some embodiments may not include more than one set of guide holes. For example, sets of guide holes 210A and 210C may be omitted, such that resection guide 200 shown in the figures only includes guide holes corresponding to set of guide holes 210B.
[0053] The resection guide 200 includes a resection plane indicator. The resection plane indicator indicates the location of one or more resection planes for resecting the femoral neck. With the resection guide 200 mounted on the guide pins 340, 342, 344 as described above, the resection plane indicator of the resection guide 200 is positioned in a predetermined location relative to the femoral head center 62. This can allow the resection plane(s) for resecting the femoral neck to be determined in a controlled manner.
[0054] In this embodiment, the resection plane indicator of the resection guide 200 comprises guide slots 202 / 204. The first portion 202 of the guide slot indicates a first resection plane, and the second portion 204 of the guide slot indicates a second resection plane. The second resection plane (corresponding to the second portion 204 of the guide slot) may extend substantially parallel to the intramedullary axis of the femur 60 when viewed from an anterior position of the femur 60 (this is shown, for example, in FIG. 2 using a dotted line labeled B). The first resection plane (corresponding to the first portion 202 of the guide slot) extends at an angle θ relative to the second resection plane. This angle θ may be, for example, approximately 127°, 129°, or 135°. While the resection plane indicator in this embodiment indicates two resection planes, it is envisioned that the resection plane indicator may indicate a single resection plane (e.g., the resection plane corresponding to the first portion 202 of the guide slot).
[0055] The resection plane indicator may alternatively include a guide surface. For example, the periphery of the resection plane indicator may include one or more substantially flat surfaces (e.g., surfaces such as surfaces 203, 205 shown in FIG. 2) for indicating the resection plane.
[0056] The guide slots 202 / 204 (or guide surfaces) may be used to mark the resection plane using a pen, scribe, etc. The guide slots 202 / 204 (or guide surfaces) may also be used as cutting slots or cutting guide surfaces to receive the blade of a cutting device during resection of the neck of the femur 60.
[0057] 2, for purposes of this disclosure, the leg length (LL) of the femur 60 may be defined as the distance between the lesser trochanter 64 and the center of the femoral head along a direction parallel to the intramedullary axis B. Referring again to FIG. 2, for purposes of this disclosure, the femoral offset of the femur 60 may be defined as the distance between the center of the femoral head and the intramedullary axis B in a direction perpendicular to the intramedullary axis B.
[0058] Thus, the resection plane indicator can be positioned using the femoral head center 312 as a reference. In this way, the location of the resection plane(s) can be determined in a controlled manner. This further means that the seating position of the implant can be controlled once the implant stem is placed in the intramedullary canal. This can facilitate restoring the leg length and / or femoral offset of the resulting femur 60, particularly, but not necessarily limited to, with femoral implants, when using implant systems with a constant implant neck length. The kit 10 can include a plurality of different shapes and / or sizes of resection guides 200. Each resection guide 200 can be used according to the implant geometry used during the hip replacement procedure. The implant geometry can include, for example, a standard lateral orientation, a short neck, and / or a coxa vara geometry.
[0059] Resection guide 200 may include features for making fine adjustments to the position of the resection plane indicator relative to femoral head center 62. For example, as described above, in this embodiment, resection guide 200 includes multiple sets 210A, 210B, 210C of guide holes. Set 210B in this embodiment may be used for normal, unadjusted mounting of resection guide 200 to position the resection plane indicator relative to femoral head center 62. Set 210A of guide holes is positioned such that when resection guide 200 is mounted on guide pins 340, 342, 344 using this set, the resection plane indicator will be positioned slightly lower relative to femur 60 to indicate the inferior resection of femur 60. This, in turn, allows the surgeon to select a slightly lower seating position, as the position of the femoral neck resection determines the seating position of the implant. Meanwhile, guide hole set 210B is positioned such that when resection guide 200 is mounted on guide pins 340, 342, 344 using this set, the resection plane indicator is positioned slightly higher relative to femur 60 to indicate a superior resection of the femur 60. Again, this in turn allows the surgeon to select a slightly higher seating position, as the location of the femoral neck resection defines the seating position of the implant. In some embodiments, visual indicators 208 (e.g., L for low, N for normal, and H for high) may be provided on the resection guide for the surgeon's reference. It is envisioned that any combination of guide hole sets may be provided on resection guide 200. For example, these sets may include a first set for "normal," unadjusted mounting of resection guide 200 on guide pins 340, 342, 344, plus zero or more "high" sets and zero or more "low" sets.
[0060] As mentioned above, the mounting portion 310 may be connected to the body portion 20. The body portion 20 may assist in the correct positioning of the mounting portion 310 on the femoral head 62 and may also allow measurements of femoral offset to be taken.
[0061] The body portion 20 includes an opening 52 for mounting the body portion 20 over an intramedullary pin 50 located in the intramedullary canal of the femur 60. The intramedullary pin 50 may include, for example, a starter rod or a reamer. The intramedullary pin 50 may be inserted into the intramedullary canal prior to mounting the body portion 20 and mounting portion 310 on the femur 60 to provide an extramedullary reference relative to the intramedullary axis B. Mounting the body portion 20 in this manner may assist in properly positioning the guide pins 340, 342, 344 by providing a reference relative to the intramedullary axis B and providing additional stability, for example, to keep the mounting portion 310 and body portion 20 in place during insertion of the guide pins 340, 342, 344 (and / or during readings, as described below). The opening 52 may comprise, for example, an aperture passing through the body portion 20. Alternatively, the opening 52 may comprise a recess on the body portion into which the intramedullary pin 50 may be received.
[0062] The position of aperture 52 may be adjustably positionable within body portion 20 according to the femoral offset of femur 60. This may allow the body portion to be adjusted so that it fits properly over intramedullary pin 50 with the mounting portion mounted on the anterior aspect of femoral head 62 as described above. Body portion 20 may also include indicia for reading the femoral offset of femur 60 according to the position of aperture 52 relative to mounting portion 310 while mounting portion 310 is mounted on femoral head 62.
[0063] The body portion 20 in this embodiment includes several arms 315 , 302 , 326 .
[0064] A first arm 315 connects the mounting portion 310 to the remainder of the body portion. In this embodiment, when the mounting portion 310 is mounted on the femoral head 62 as described above, the first arm 315 extends in a direction substantially parallel to the intramedullary axis B.
[0065] First arm 315 is connected to second arm 302 of body portion 20. Second arm 302 extends in a direction perpendicular to first arm 315 such that when mounting portion 310 is mounted on femoral head 62 as described above, second arm 302 extends laterally relative to mounting portion 310 along a direction perpendicular to intramedullary axis B and perpendicular to the central axis of mounting portion 310.
[0066] The body portion also includes a third arm 326. The third arm 326 is connected to the second arm 302 at a location lateral to the mounting portion 310. The third arm 326 extends in a direction substantially parallel to the central axis of the mounting portion 310 such that when the mounting portion 310 is mounted on the femoral head 62 as described above, the third arm extends in a direction substantially perpendicular to the intramedullary axis B. An opening 52 may be provided in the third arm 326. In this embodiment, the opening 52 is located at the posterior end of the third arm 326. The other end of the third arm 326 may include a handle 316 for manual positioning and adjustment of the third arm 326, for example, when mounting the opening on the intramedullary pin 50.
[0067] The relative positions of the arms 315, 302, 326 may be adjustable so that the body portion 20 can be adjusted so that it fits properly onto the intramedullary pin 50 once the mounting portion 310 is mounted on the anterior aspect of the femoral head 62 as described above.
[0068] In this embodiment, the second arm 302 is slidably received within an opening located at the upper end 304 of the first arm 315. This can allow the second arm 32 to be slid back and forth in an outer / inner direction relative to the first arm 32. Similarly, the third arm 326 is slidably received within an opening located at the outer end 324 of the second arm 302. This can allow the third arm 326 to be slid back and forth in a rearward / forward direction relative to the second arm 302.
[0069] 3, the upper end 304 of the first arm 315 may include a window through which indicia 306 located on the second arm 302 may be viewed. These indicia 306 may be used to read the femoral offset away from the femur 60 when the mounting portion 310 and body portion 20 are positioned on the femur 60 as described above.
[0070] 4, the outer end 324 of the second arm 326 may include a window through which markings 328 located on the third arm 326 may be viewed. These markings 328 may be used to measure anterior and posterior offsets and to indicate natural femoral deformities when the mounting portion 310 and body portion are positioned on the femur 60 as described above.
[0071] The implant placed in the femur 60 may generally include a stem that is received in the intramedullary canal and a head with a bearing surface that is received in the acetabulum or an acetabular cup implant. The implant also typically includes a neck that extends between the proximal end of the stem and the head. The stem and neck may be integrally formed. The head may be attachable to the end of the neck. A reading using the indicia 306, as well as the size (diameter / radius) of the femoral head 62, can be used to inform the selection of the head to be used to restore the femoral offset.
[0072] Thus, a surgical kit and method for performing a controlled resection of the femoral neck during a hip replacement procedure have been described. The kit includes a mounting portion. The mounting portion includes at least two guide holes for inserting guide pins into the femoral head while the mounting portion is positioned on the anterior aspect of the femoral head. The kit also includes a resection guide including at least two guide holes having the same arrangement as the guide holes in the mounting portion such that the resection guide can be mounted on the anterior aspect of the femoral head with the guide pins inserted into the femoral head to position the resection plane indicator of the resection guide relative to the neck of the femur. The method also includes disposing the mounting portion on the anterior aspect of the femoral head. The method further includes inserting a respective guide pin into the femoral head through each guide hole in the mounting portion. The method also includes removing the mounting portion from the femoral head. The method further includes mounting the resection guide on the anterior aspect of the femoral head with the guide pins inserted into the femoral head to position the resection plane indicator of the resection guide. The method also includes using a resection plane indicator to either mark the location of a resection plane on the neck of the femur or to guide a blade of a cutting device to resect the neck of the femur.
[0073] While particular embodiments of the present invention have been described above, it will be appreciated that many modifications / additions and / or substitutions may be made within the scope of the invention as claimed.
[0074] [Embodiment] (1) A surgical kit for performing controlled resection of the neck of a femur during a hip replacement procedure, said surgical kit comprising: a mounting portion including at least two guide holes for inserting guide pins into the femoral head while the mounting portion is positioned on the anterior aspect of the femoral head; a body portion connected to the mounting portion, the body portion including an opening for mounting the body portion over an intramedullary pin located in the intramedullary canal of the femur; a resection guide including at least two guide holes having the same arrangement as the guide holes of the mounting portion so as to allow the resection guide to be mounted on the anterior side of the femoral head with the guide pin inserted into the femoral head to position a resection plane indicator of the resection guide relative to the neck of the femur. (2) A surgical kit according to embodiment 1, wherein the resection plane indicator indicates the positions of two resection planes. (3) The surgical kit of embodiment 2, wherein the two resection planes are oriented at an angle of approximately 127°, 129°, or 135° relative to each other. (4) A surgical kit according to any one of embodiments 1 to 3, wherein the resection plane indicator comprises a guide slot or a guide surface. (5) The surgical device of embodiment 4, wherein the guide slot or guide surface is a cutting slot or cutting guide surface for receiving a blade of a cutting device during the resection of the neck.
[0075] (6) A surgical kit according to any one of embodiments 1 to 5, wherein the resection guide includes a plurality of sets of guide holes, each set including at least two guide holes having the same arrangement as the guide holes of the mounting portion, and the plurality of sets of guide holes are each positioned within the resection guide so as to enable adjustment of the position of the resection plane indicator relative to the neck of the femur by mounting the resection guide on the anterior side of the femoral head with the guide pin inserted into one of the sets of guide holes. (7) A surgical kit according to any one of embodiments 1 to 6, wherein the attachment portion includes three of the guide holes. (8) The guide hole of the mounting portion is a central guide hole for aligning the attachment portion with a central portion of the femoral head when the attachment portion is positioned on the anterior side of the femoral head; an outer guide hole located on a first side of the central guide hole; 8. The surgical kit of claim 7, further comprising an inner guide hole located on a second side opposite the first side of the central guide hole. (9) A surgical kit according to any one of embodiments 1 to 8, further comprising a plurality of the guide pins. (10) A surgical kit according to any one of embodiments 1 to 9, wherein the opening for mounting the body portion onto the intramedullary pin is adjustably positionable within the body portion according to the femoral offset of the femur.
[0076] (11) The surgical kit of claim 10, wherein the body portion includes markings for reading the femoral offset of the femur according to the position of the opening for mounting the body portion onto the intramedullary pin while the mounting portion is mounted on the femoral head. (12) A surgical kit according to any one of embodiments 1 to 11, wherein the kit includes a plurality of resection guides, each of which is of a different shape and / or size according to the geometry of a respective implant, for positioning the resection plane indicator of the selected resection guide relative to the neck of the femur. (13) A surgical kit according to any one of embodiments 1 to 12, wherein the attachment portion has a substantially circular femoral head contact surface. (14) A method for performing controlled resection of the neck of a femur during a hip replacement procedure using a surgical kit, the surgical kit comprising: a mounting portion including at least two guide holes for receiving pins; a body portion connected to the mounting portion, the body portion having an opening; a resection guide including at least two guide holes having the same arrangement as the guide holes of the attachment portion; The method comprises: mounting the body portion onto an intramedullary pin located within the intramedullary canal of the femur by inserting the pin into the opening in the body portion; disposing the mounting portion on the anterior aspect of the femoral head; inserting a respective guide pin through each guide hole in the mounting portion and into the femoral head; removing the attachment portion from the femoral head; mounting the resection guide on the anterior aspect of the femoral head with the guide pin inserted into the femoral head to position a resection plane indicator of the resection guide; Using the resection plane indicator, marking the location of the resection plane on the neck of the femur; or and guiding a blade of a cutting device to resect the neck of the femur. (15) The resection guide includes a plurality of sets of guide holes, each set including at least two guide holes having the same arrangement as the guide holes of the mounting portion, and the plurality of sets of guide holes are respectively positioned within the resection guide to enable adjustment of the position of the resection plane indicator relative to the neck of the femur by mounting the resection guide on the anterior aspect of the femoral head with the guide pin inserted into one of the sets of guide holes, and the method further comprises: selecting a set of guide holes; Attaching the resection guide to the anterior aspect of the femoral head with the guide pins inserted into one set of the guide holes of the selected set of guide holes.
[0077] (16) The method of claim 14 or claim 15, comprising adjustably positioning the opening for mounting the body portion onto the intramedullary pin relative to the remainder of the body portion according to a femoral offset of the femur. (17) The method of claim 16, further comprising reading the femoral offset of the femur according to the position of the opening for mounting the body portion onto the intramedullary pin relative to the remainder of the body portion according to the femoral offset of the femur while the mounting portion is mounted on the femoral head. (18) The method of embodiment 17, comprising using the femoral offset value to determine the femoral offset of a femoral implant to be installed in the hip replacement procedure. (19) The kit includes a plurality of the resection guides, each of which is of a different shape and / or size according to the geometry of a respective implant for positioning a resection plane indicator of a selected resection guide relative to the neck of the femur, and the method includes: selecting one of the resection guides; A method according to any one of embodiments 14 to 18, further comprising attaching the selected resection guide onto the anterior aspect of the femoral head with the guide pin inserted into the femoral head. (20) A method according to any one of embodiments 14 to 19, comprising inserting the intramedullary pin into the intramedullary canal of the femur before mounting the body portion onto the intramedullary pin.
[0078] (21) A method according to any one of embodiments 14 to 20, wherein the attachment portion has a substantially circular femoral head contact surface.
Claims
1. 1. A surgical kit for performing controlled resection of the neck of a femur during a hip replacement procedure, said surgical kit comprising: an attachment portion including at least two guide holes for inserting guide pins into the femoral head while the attachment portion is positioned on the anterior side surface of the femoral head, and an O-ring shaped portion that contacts the femoral head while the attachment portion is positioned on the anterior side surface of the femoral head, wherein the surface of the O-ring shaped portion that contacts the femoral head when the attachment portion is attached on the anterior side surface of the femoral head is circular when viewed from the extension direction of the guide pins; a body portion connected to the mounting portion, the body portion including an opening for mounting the body portion over an intramedullary pin located in the intramedullary canal of the femur; a resection guide including at least two guide holes having the same arrangement as the guide holes of the mounting portion so as to allow the resection guide to be mounted on the anterior side of the femoral head with the guide pin inserted into the femoral head to position a resection plane indicator of the resection guide relative to the neck of the femur.
2. the resection plane indicator comprises a guide slot or guide surface that indicates the location of the first and second resection planes; the guide slot comprises a first portion that indicates the first resection plane and a second portion that indicates the second resection plane; the guide surface comprises a first planar surface that indicates the first resection plane and a second planar surface that indicates the second resection plane; The surgical kit of claim 1 , wherein the first resection plane is oriented at an angle relative to the second resection plane.
3. The surgical kit of claim 2 , wherein the predetermined angle is 127°, 129°, or 135°.
4. The surgical kit of claim 2 , wherein the guide slot or guide surface is a slot or surface for guiding a blade of a cutting device during the resection of the neck.
5. 5. The surgical kit of claim 1, wherein the resection guide includes a plurality of sets of guide holes, each set including at least two guide holes having the same arrangement as the guide holes of the mounting portion, and the plurality of sets of guide holes are respectively positioned within the resection guide to enable adjustment of the position of the resection plane indicator relative to the neck of the femur by mounting the resection guide on the anterior side of the femoral head with the guide pin inserted into one set of the plurality of sets of guide holes.
6. The surgical kit according to any one of claims 1 to 5, wherein the attachment portion includes three of the guide holes.
7. The guide hole of the mounting portion is a central guide hole for aligning the attachment portion with a central portion of the femoral head when the attachment portion is positioned on the anterior side of the femoral head; an outer guide hole located on a first side of the central guide hole; The surgical kit of claim 6, further comprising an inner guide hole located on a second side of the central guide hole opposite the first side.
8. The surgical kit according to any one of claims 1 to 7, further comprising a plurality of said guide pins.
9. the body portion includes a first arm, a second arm, and a third arm; the first arm connects the mounting portion to the body portion and extends in a direction parallel to the intramedullary axis when the mounting portion is mounted on the femoral head; the second arm extends perpendicular to the first arm, is slidably received in an opening at an upper end of the first arm, and is slidable in an outward / inward direction relative to the first arm; the third arm is slidably received within an opening at an outer end of the second arm and is slidable in a rearward / forward direction relative to the second arm; the opening is located at a rear end of the third arm; 9. The surgical kit of claim 1, wherein when the mounting portion is mounted on the femoral head, the opening is adjustably positionable within the body portion by adjusting the relative positions of the first to third arms to mount the opening onto the intramedullary pin.
10. the second arm includes markings for reading a femoral offset of the femur; the first arm includes a window at the upper end of the first arm for viewing the indicia; the femoral offset is the distance between the center of the femoral head and the intramedullary axis in a direction perpendicular to the intramedullary axis; The surgical kit of claim 9 , wherein the indicia are visible through the window while the mounting portion is mounted on the femoral head.