JP2007075517A - Jig for mounting artificial knee joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a jig for mounting an artificial knee joint which can reduce burden on an operator in artificial knee joint mounting surgery. <P>SOLUTION: The jig (1) for mounting an artificial knee joint is used for a knee in a bent state, and has a thigh mounted member (2) mounted to a thigh (F) and a jig body (4) which abuts on a proximal end face (Tb) of a tibia (T) and a distal end face (Fb1) of the thigh bone (F). The thigh mounted member (2) and the jig body (4) are connected to each other to cause a prescribed tense condition to a ligament, relatively movably in a direction vertical to the proximal end face (Tb) of the tibia (T) and engageably at an optional relative position. The jig body (4) has a guide hole (46) to form a mount reference hole common to artificial knee joints with different sizes in the distal end face (Fb1) of the thigh (F) and an indication portion (48) which indicates the installation surface (Fb2) of the thigh bone (F) corresponding to the artificial knee joints with different sizes. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an implant placement jig, and more particularly to an artificial knee joint placement jig.

  Artificial knee joints are sometimes used to treat patients who have osteoarthritis or chronic rheumatism due to wear of the knee cartilage. FIG. 5 is a schematic side cross-sectional view showing a femur and a tibia in which an artificial knee joint is installed. As shown in FIG. 5, the artificial knee joint 100 includes the femur F so as to cover the tibial tray 102 and the surface liner 104 fixed to the proximal end Ta of the tibia T and the distal end Fa of the femur F. And a femoral component 106 secured to the body. In some cases, a spacer (not shown) is inserted between the tibial tray 102 and the tibia T. The femur F and the tibia T are connected to each other by a ligament (not shown) arranged on both the left and right sides and pulled from each other, whereby the femoral component 106 is pressed against the surface liner 104. In such an artificial knee joint 100, the femoral component 106 slides along the surface liner 104 when the knee is moved between a bent position (flexion position) and an extended position (extension position). Since the size of the femur F varies from patient to patient, several different sizes of knee prosthesis 100 are prepared.

  FIG. 6 is a schematic side view showing the tibia and femur partially cut away for placement of the knee prosthesis. As shown in FIG. 6, the proximal end Ta of the tibia T has an installation surface for removing the worn cartilage and fixing the tibial tray 102 to the tibia T, that is, the proximal end surface Tb. Has been excised to form. Similarly, the distal end Fa of the femur F is used to remove worn cartilage and to form five mounting surfaces Fb1-Fb5 for securing the femoral component 106 to the femur F. Has been excised. The five installation surfaces are a distal end surface Fb1, a front installation surface Fb2 and a rear installation surface Fb3 perpendicular to the distal end surface Fb1, and a distal end surface Fb1, a front installation surface Fb2, and a rear installation surface Fb3. Two inclined installation surfaces Fb4 and Fb5. In general, the proximal end surface Tb of the tibia T and the distal end surface Fb1 of the femur F are formed at predetermined distances LT and LF from the proximal end of the tibia T and the distal end of the femur, respectively. Is done. On the other hand, the positions of the installation surfaces Fb <b> 2 to Fb <b> 5 of the femur F change according to the size of the artificial knee joint 100.

  In order to determine the installation position of the artificial knee joint 100, specifically, the positions of the front installation surface Fb2, the rear installation surface Fb3, and the inclined installation surfaces Fb4 and Fb5 of the femur F for attaching the femoral component 106 are determined. In order to do so, an artificial knee joint installation jig has been conventionally used (see, for example, Patent Document 1).

  With reference to FIG.7 and FIG.8, the jig | tool for artificial knee joint installation currently disclosed by patent document 1 and its usage method are demonstrated. 7 and 8 are side views of the artificial knee joint installation jig when the knee is in the extended position and the bent position, respectively.

  As shown in FIG. 8, the artificial knee joint installation jig 110 includes a spacer 112 that is a first jig and a block assembly 114 that is a second jig. The spacer 112 has an appropriate thickness. The block assembly 114 includes a rod member 116 attached to the femur F, a guided movable block 118 that can move relative to the rod member 116 in a movement direction 116a perpendicular to the proximal end surface Tb of the tibia T, and And a stylus 120 removably fixed to the guide movable block 118. The movable block with guide 118 has a front guide surface 122a, a rear guide surface 122b, and two inclined guide surfaces 122c, 122d aligned with the front installation surface Fb2, the rear installation surface Fb3, and the two inclined installation surfaces Fb4, Fb5, respectively. ing. The stylus 120 is attached to the anterior guide surface 122a and has a tip portion 120a for indicating the proximal end of the anterior placement surface Fb2 of the femur F. Thus, the tip 120a is located in the same plane as the front guide surface 122a.

  The method of using the artificial knee joint installation jig 110 is generally used to adjust the tension state of the ligament when the knee is in the extended position (first step; see FIG. 7), and then the knee. Is used to match the tension of the ligament when the knee is in the flexed position to the tension of the ligament when the knee is in the extended position (step 2; see FIG. 8), and finally the femur is excised And used to form the installation surface of the femoral component (third step; see FIG. 8). Before using the artificial knee joint installation jig 110, the tibia T and the femur F are excised to form a proximal end face Tb of the tibia T and a distal end face Fb1 of the femur F.

  First, in the first step, as shown in FIG. 7, the knee is in the extended position, and an appropriate thickness as a first jig is provided between the proximal end surface Tb of the tibia T and the distal end surface Fb1 of the femur F. The spacer 112 is inserted. Specifically, since the proximal end surface Tb and the distal end surface Fb1 of the patient on which the knee prosthesis 100 is installed are not parallel, the soft tissue of the ligament that connects the tibia T and the femur F The spacer 112 is inserted between the tibia T and the femur F after releasing a part (not shown) so that the proximal end face Tb and the distal end face Fb1 are parallel. Next, in order to obtain a predetermined tensile force or tension of the ligament, the thickness of the spacer 112 is increased or decreased, and the soft tissue is further released. The tensile force of a predetermined size of the ligament is, for example, a tensile force that the spacer 112 is stably held between the proximal end surface Tb and the distal end surface Fb1 with an appropriate force. Thus, a uniform and predetermined tensile force is applied to the left and right ligaments, thereby adjusting the tension of the ligaments when the knee is in the extended position.

  Next, in the second step, as shown in FIG. 8, the knee is bent 90 degrees and the block assembly 114, which is the second jig, is attached to the distal end face Fb <b> 2 of the femur F. A spacer 112 that is a first jig is disposed between the proximal end surface Tb of the tibia T 118 and the tibia T. The thickness of the spacer 112 is determined in the first step and is the same as the thickness of the spacer 112. Moving the guided movable block 118 in the movement direction 116a with respect to the rod member 116 changes the distance between the tibia T and the femur F, thereby ligament tension when the knee is in a flexed position. The state can be changed. Thus, the tension state of the ligament when the knee is in the bent position can be matched with the tension state of the ligament when the knee is in the extended position. At this position, the guided movable block 118 is fixed to the femur F.

  Finally, in the third step, the spacer 112 is removed, leaving only the guided movable block 118, and the osteotomy blade is moved toward the femur F along the guide surfaces 122 a to 122 d of the guided movable block 118. The femur F is excised. Thus, the installation surfaces Fb2 to Fb5 of the femur F are formed.

  By the way, as mentioned above, since the positions of the installation surfaces Fb2 to Fb5 of the femur F change according to the size of the artificial knee joint 100, the guide surfaces 122a to 122d for forming these installation surfaces Fb2 to Fb5. The guide movable block 118 having different sizes is prepared in accordance with the size of the artificial knee joint 100. Since the size of the knee prosthesis 100 has not been determined at the time when the first step is completed, the movable block with guide 118 having a temporarily selected size is used in the second step.

  Further, the position of the anterior installation surface Fb2 of the femur F is substantially determined according to the shape of the anterior femoral condyle Fc, and is roughly at a position where the tip 120a of the stylus 120 abuts the femur F. Become.

  In the second step that is actually performed, the position of the movable block with guide 118 (first position) when the distal end portion 120a of the stylus 120 abuts against the front mounting surface Fb2 of the femur F, and the ligament in the bent position If the position of the guided movable block 118 (second position) when the tensioned state is matched with the tensioned state of the ligament in the extended position, the size of the selected guided movable block 118 is the femur. The size of the artificial knee joint adapted to the above, and the process can proceed to the next third step. On the other hand, if the first position and the second position are significantly different, the size of the guide-equipped movable block 118 selected is not the size of the artificial knee joint adapted to the femur. Must be replaced with one of a different size (see paragraph 0031 of Patent Document 1). For example, if the spacer 112 does not enter between the guided movable block 118 and the tibia T when the guided movable block 118 is in the first position, the size of the guided movable block 118 needs to be reduced. On the other hand, when the guided movable block 118 is in the first position with the spacer 112 inserted, if the tension state of the ligament in the bent position is considerably smaller than the tension state of the ligament in the extended position, The size of the guided movable block 118 needs to be increased. When the size of the guided movable block 118 is changed, the second step may be performed again.

European Patent No. 1442711

  Japanese people have more opportunities to sit straight than Westerners, so by matching the tension of the ligaments in the flexed position to the tension of the ligaments in the extended position, the feeling of discomfort and wear after installing the knee prosthesis can be reduced. There is a particular need to reduce. As described above, when the conventional artificial knee joint installation jig 110 is used, the tension state of the ligament in the bending position and the tension state of the ligament in the extension position can be matched. However, when the first position does not coincide with the second position in the second step, the size of the guided movable block 114 needs to be changed, and the operation time may be extended. In detail, it is only after confirming the tension state of the ligament using the temporarily selected movable block 118 with a guide whether it is necessary to change the size of the movable block 118 with a guide. Therefore, if the size of the guided movable block 118 selected does not match the size of the artificial knee joint to be installed, the size of the guided movable block 118 is changed and the tension state of the ligament is confirmed again. Become. This repeated work may be a burden on the operator.

  In addition, there is room for reflecting the operator's request to make the artificial knee joint installation jig easier to use.

  Then, this invention is providing the jig for artificial knee joint installation which can reduce the burden of the operator in the artificial knee joint installation operation.

  In order to achieve the above object, an artificial knee joint installation jig according to the present invention is an artificial knee joint installation jig used when the knee is in a bending position, and includes a femoral attachment member attached to the femur, an excision A jig body that abuts on the proximal end surface of the tibia and the distal end surface of the femur formed by the tibia, and the femoral attachment member and the jig body have a predetermined ligament for connecting the tibia and the femur. In order to generate a tension state, the jig body is connected to each other so as to be movable in a direction perpendicular to the proximal end surface of the tibia and to be locked at an arbitrary relative position. It has a guide hole for forming a reference hole in the distal end surface of the femur, and an instruction unit for indicating the front installation surface of the femur corresponding to the artificial knee joints having different sizes.

  According to the artificial knee joint installation jig configured as described above, when the knee is in the bending position, the femoral attachment member attached to the femur and the jig main body abutting on the proximal end surface of the tibia are A predetermined tension state is given to the ligament connecting the tibia and the femur by relative movement in a direction perpendicular to the proximal end surface, and the ligament is locked in that state. Thereby, for example, it is possible to give a tension state that matches the tension state of the ligament when the knee is in the extended position. Next, using the guide hole of the jig body, an installation reference hole common to artificial knee joints having different sizes is formed in the distal end face of the femur. Furthermore, the size of the knee prosthesis suitable for the patient is selected from the anterior setting surface of the femur corresponding to the knee prosthesis having a different size, which is instructed by the indicator of the jig body. In addition, the front installation surface of a femur is a surface for installing the artificial knee joint formed in the front side of a femur seeing from a patient.

  The jig for installing an artificial knee joint according to the present invention differs from the prior art artificial knee joint installation jig in that the ligament tension state when the knee is in the flexed position matches the tension state of the ligament when the knee is in the extended position. There is no need to temporarily select the size of the knee prosthesis. Instead, after matching the tension state of the ligament in the extended position and the bent position, the size of the artificial knee joint is determined by the indicator of the jig body. In addition, since an installation reference hole common to artificial knee joints of different sizes is formed on the distal end surface of the femur, the step of forming the installation surface of the artificial knee joint after determining the size of the artificial knee joint is, for example, artificial This can be done by fixing a bone resection jig prepared for each size of the knee joint to the femur according to the installation reference hole. Therefore, it is possible to proceed with an artificial knee joint placement operation without repeating the same process, and as a result, the operation time can be shortened and the burden on the operator can be reduced.

  In an embodiment of an artificial knee joint placement jig according to the present invention, preferably, the jig body has a spacer disposed on the proximal end surface of the tibia, a removably connected to the spacer, and abuts on the distal end surface of the femur. The femoral attachment member and the movable block are connected to each other so as to be relatively movable in a direction perpendicular to the proximal end surface of the tibia and to be locked at an arbitrary relative position.

  In an artificial knee joint installation jig configured in this way, the jig body can be separated into a spacer and a movable block, so even if the part of the patient's knee incised to install the artificial knee joint is small, By first attaching the movable block to the femur and subsequently inserting the spacer, the jig can be placed on the patient's knee to place the knee prosthesis. Thereby, the burden on the patient and the operator can be reduced.

  In this embodiment, more preferably, the spacer has an upper surface that contacts the movable block, a bracket extending upward from the upper surface, and a pin extending from the bracket in parallel to the upper surface and in the front-rear direction. The lower surface is in contact with the upper surface of the spacer body, and the insertion hole into which the pin is inserted in the fitted state with the lower surface in contact with the upper surface of the spacer.

  In the artificial knee joint installation jig configured as described above, after the movable block is first installed on the femur, the spacer is moved in the front-rear direction while the lower surface of the movable block and the upper surface of the spacer are in contact with each other. By inserting this pin into the insertion hole of the movable block, relative movement in the vertical direction and the horizontal direction between the movable block and the spacer is prevented. Further, the relative movement in the front-rear direction between the movable block and the spacer is also limited by friction between the spacer and the tibia and the movable block. Thus, the spacer can be easily fixed to the movable block, and the burden on the operator during the operation can be reduced. More preferably, the pins are two or more pins extending in parallel to each other. The up-down direction is the direction in which the tibia extends, and the front-back direction and the left-right direction are the patient's front-back direction and left-right direction in the tibia, respectively.

In the embodiment of the artificial knee joint installation jig according to the present invention, the indicating unit may be a scale indicating the front installation surface of the artificial knee joints having different sizes, or the front installation of the artificial knee joints having different sizes. There may be a plurality of guide surfaces aligned with the surface.
In this embodiment, the size of the knee prosthesis can be easily determined by a scale or a guide surface.

In the embodiment of the artificial knee joint installation jig according to the present invention, preferably, the jig main body further includes a handle.
In this embodiment, as a method for confirming the tension state of the human body in the bent position, a method of shaking the jig body is added as an option, and it is possible to provide a jig for installing an artificial joint that meets the demands of more surgeons. Become.

  The artificial knee joint installation jig according to the present invention can reduce the burden on an operator in an artificial knee joint installation operation.

  Hereinafter, an embodiment of an artificial knee joint installation jig according to the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of an artificial knee joint installation jig which is an embodiment of the present invention attached to a knee in a bent position. FIG. 2 is a partially exploded perspective view of the artificial joint jig according to the present invention. In the following description of the artificial knee joint installation jig itself, the direction in which the tibia extends is referred to as the up-down direction, and the front-back direction and the left-right direction of the patient in the tibia are referred to as the front-back direction and the left-right direction, respectively. Therefore, in the bent position, the femur side with respect to the tibia is the posterior side.

  As shown in FIG. 1, the jig 1 is a jig that abuts a femoral attachment member 2 attached to the femur, a proximal end surface Tb of the tibia T formed by resection, and a distal end surface Fb1 of the femur F. And a main body 4. As will be described later, the femoral attachment member 2 and the jig body 4 are arranged in a direction perpendicular to the proximal end surface Tb of the tibia T in order to generate a predetermined tension state in the ligament that connects the tibia T and the femur F. They are connected to each other such that they can move relative to each other and can be locked at an arbitrary relative position.

  As shown in FIG. 2, the femoral attachment member 2 includes a rod portion 6 that is inserted from the distal end face Fb1 of the femur F into the femur F along the axis Fd, and a direction perpendicular to the axis Fd, that is, up and down. And a cylindrical portion 8 connected to the rod portion 6 so as to extend in the direction 8a. In the cylindrical portion 8, a screw thread 10 is formed on the opposite side of the rod portion 6. The cross section of the rod portion 6 is circular, and the jig body 4 can rotate around the rod portion 6 with respect to the femur F.

  The jig body 4 includes a spacer 12 disposed on the proximal end surface Tb of the tibia T, a movable block 14 that is detachably fixed to the spacer 12 and abuts on the distal end surface Fb1 of the femur F, and is detached from the movable block 14. And a handle 16 (see FIG. 1) attached thereto.

  The spacer 12 includes a spacer body 18 and a plurality of additional spacers 20 that are pivotally attached to the spacer body 18 so that the spacer body 18 can overlap the spacer body 18. The thickness of the additional spacer is preferably the same thickness as a spacer (not shown) that is selectively inserted between the tibial tray 102 and the tibia T (see FIG. 5). The spacer body 18 has a lower surface 18a that abuts on the proximal end surface Tb of the tibia T and an upper surface 18b that abuts on the movable block 14, and the lower surface 18a and the upper surface 18b are arranged in parallel with each other by a predetermined distance. Has been. The lower surface 18a is preferably relatively large in order to ensure the stability of the tibia T and the jig body 4, but the upper surface 18b ensures a view during surgery if the connection with the movable block 14 is ensured. Therefore, it is preferable that it is relatively small. Therefore, in this embodiment, most of the upper surface side portion of the spacer body 18 is removed (see FIG. 2). The spacer body 18 further includes a handle portion 22 and a connecting portion 24 connected to the movable block 14. The connecting portion 24 has a bracket 26 extending upward from the upper surface 18b and two pins 28 extending from the bracket 26 in the front-rear direction in parallel with the upper surface 18b and in parallel with each other. Further, the additional spacer 20 is rotatably attached to the handle portion 22 via a pin 20a.

  The movable block 14 has a lower surface 14a that contacts the upper surface 18b of the spacer body 18, a rear surface 14b that contacts the distal end surface Fb1 of the femur F, and a front surface 14c opposite to the rear surface. The lower surface 14a, the rear surface 14b, and the front surface 14a are perpendicular to each other, and the rear surface 14b and the front surface 14a are parallel to each other. The lower surface 14a of the movable block 14 is preferably aligned with the posterior installation surface Fb3 of the femur. The bracket 26 of the spacer main body 18 can contact the front surface 14c, and the two pins 28 are inserted in a fitted state with the lower surface 14a of the movable block and the upper surface 18b of the spacer main body 18 in contact with each other. Two insertion holes 30 are provided. As a result, when the pin 28 is inserted into the insertion hole 30, the vertical direction and the horizontal direction between the movable block 14 and the spacer body 18 are blocked, and the relative movement in the front-rear direction 14d is performed. Is limited by the friction between the spacer body 18 and the tibia T and the movable block 14. In that sense, the spacer body 18 is fixed to the movable block 14.

  FIG. 3 is a cross-sectional view of the movable block. FIG. 4 is a plan view of the movable block. As shown in FIGS. 3 and 4, the movable block 14 has two holes, ie, a front hole 32 and a rear hole 34, which extend in the vertical direction 8a and are arranged side by side in the front-rear direction 14d. The front hole 32 and the rear hole 34 partially overlap each other, and a front slot 36 is formed between them. The rear hole 34 is positioned so as to exceed the rear surface 14b, and a rear slot 38 is formed. The inner diameters of the front hole 32 and the rear hole 34 are the same, and the rear hole 34 accepts the cylindrical portion 8 of the femoral attachment member 2 so as to be fitted and slidable in the vertical direction.

  The movable block 14 further has a drive screw 40 for moving the femoral attachment member 2 and the movable block 14 relative to each other, and a support pin 42 that rotatably supports the drive screw 40. The drive screw 40 is slidably and rotatably fitted in the front hole 32, and has an annular recess 40a. Further, the support pin 42 is inserted into a support pin hole 44 provided in the movable block 14 so as to pass through the front hole 32 by shifting the core. The annular recess 40a of the drive screw 40 inserted in the front hole 32 and the support pin 42 inserted in the support pin hole 44 are engaged, and the drive screw 40 is rotatably supported in the front hole 32. Yes.

  The outer diameter of the drive screw 40 and the pitch thereof are respectively equal to the outer diameter of the cylindrical portion 8 and the pitch of the thread 10 formed thereon. Thus, the drive screw 40 and the cylindrical portion 8 are engaged with each other via the front slot 36, and when the drive screw 40 supported by the support pin 42 rotates, the cylindrical portion 8 is in relation to the drive screw 40. It is configured to move in the vertical direction 8a. The drive screw has a hexagon hole 40b for receiving a hexagon wrench that rotates the drive screw.

  The posterior slot 38 is formed larger than the rod portion 6 of the femoral attachment member 2, and thus the femoral attachment member 2 can be rotated concentrically with the posterior hole 34. The rotation angle is preferably about 10 degrees on each of the left and right sides.

  Furthermore, as shown in FIG. 2, the movable block 14 includes a reference guide hole 46 for forming an installation reference hole common to artificial knee joints of different sizes in the distal end face Fb1 of the femur F, and artificial prostheses of different sizes. It has an instruction portion 48 that indicates the front installation surface of the femur corresponding to the knee joint, and a fixed guide hole 50 into which a pin for fixing the movable block 14 to the femur F is inserted.

  Three reference guide holes 46 are provided on the left and right, and one fixed guide hole 50 is provided on the left and right.

  The instruction unit 48 has a scale 48a that indicates the front placement surface Fb2 of artificial knee joints of different sizes, and is indicated by lines with numerals 55, 60, 65, and 70 in FIG. Moreover, the instruction | indication part 48 has the some guide surface 48b aligned with the front installation surface Fb2 of the artificial knee joint from which size differs. In the present embodiment, the guide surface 48b includes a guide surface aligned with the scale 48a and a guide surface arranged therebetween. The guide surface 48b forms a slit, and the width of the slit is preferably wide enough to accept a blade for resecting the femur.

Next, a method of using the artificial knee joint installation jig according to the present invention will be described.
First, the femoral member 2 and the movable block 14 are assembled. Specifically, the drive screw 40 is inserted into the front hole 32, the support pin 42 is inserted into the support pin hole 44 and the annular recess 40 a of the drive screw 40, and the drive screw 40 is rotatably supported in the front hole 32. . Next, when the cylindrical portion 8 of the femoral attachment member 2 is inserted into the rear hole 34 and the thread 10 of the cylindrical portion 8 is engaged with the drive screw 40, the drive screw 40 is rotated with a hexagon wrench or the like. The femoral attachment member 2 and the movable block 14 are relatively moved in the vertical direction 8a.

  The knee is bent 90 degrees, the rod portion 6 of the femoral attachment member 2 is inserted into the bone marrow cavity of the femur F, and the rear surface 14b of the movable block 14 is brought into contact with the distal end surface Fb1 of the femur F. Next, the spacer body 18 and the auxiliary spacer 20 are combined so as to have the same thickness as the predetermined gap between the femur F and the tibia T measured when the knee is in the extended position, and the spacer 12 (18, 20), and this spacer 12 is inserted between the movable block 14 and the proximal end face Tb of the tibia T. The auxiliary spacer 20 that is not used is rotated around the pin 20 a and is separated from the spacer body 18. When inserting the spacer 12, the pin 28 of the spacer 12 and the insertion hole 30 of the movable block 14 are aligned, and the pin 28 is inserted into the insertion hole 30 to connect and fix the movable block 14 and the spacer 12. .

  Next, the drive screw 40 is rotated with a hexagon wrench or the like, and the movable block 14 is lowered with respect to the femoral attachment member 2, that is, the distance between the femur F and the tibia T is widened, and the tension state of the ligament in the bending position is increased. Match with the tension state of the ligament in the extended position. A method for confirming whether the tension state of the ligament in the bending position matches the tension state of the ligament in the extension position is a method of rotating the drive screw 40 until the torque of the hexagon wrench reaches a predetermined value, and There is a method of checking the stability or rattling of the jig body 2 attached between the femur F and the tibia T by shaking the handle 16 attached to the movable block 14 by hand. The latter method is a method that depends on the experience of the operator, but depending on the operator, is one of the very effective methods.

  When the desired tension state of the ligament is obtained, a drill is inserted into the middle hole of the reference guide hole 46 provided on each of the left and right of the movable block 14, and the reference hole provided in the distal end face Fb1 of the femur F is inserted. Form. When re-opening the installation reference hole, another reference guide hole 46 may be used.

  In addition, the position of the anterior placement surface Fb2 adapted to the femur F is determined from the scale 48a and the guide surface 48 of the pointing portion 48 and the shape of the anterior femoral condyle Fc, thereby determining the size of the artificial knee joint. To do. If desired, after fixing the movable block 14 to the femur F by inserting a fixing pin into the left and right fixed guide holes 50 of the movable block 14 and temporarily fixing the movable block 14 to the femur F, the guide surface of the determined front installation surface Fb2 The bone excision blade may be moved toward the femur F along 48 to form the anterior installation surface Fb2 of the femur F.

  Finally, the artificial knee joint installation jig 1 is removed, and, for example, the osteotomy jig is fixed to the distal end face Fb1 of the femur F using the installation reference hole formed in the femur F. Installation surfaces Fb2 to Fb5 are formed.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the invention described in the claims. Needless to say, these are also included within the scope of the present invention.
In the above embodiment, the jig body 4 is constituted by the spacer 12 and the movable block 14. However, if the jig body 4 can be inserted from the incision portion of the patient's knee, the jig in which the spacer 12 and the movable block 14 are integrated. The main body 4 may be adopted.
In the above embodiment, the handle 16 is fixed to the movable block 14, but may be fixed to the spacer body 18.

1 is a perspective view of an artificial knee joint jig according to the present invention attached to a knee in a bent position. FIG. 1 is a partially exploded perspective view of an artificial joint jig according to the present invention. FIG. It is sectional drawing of a movable block. It is a top view of a movable block. It is a schematic side sectional view showing a femur and a tibia in which an artificial knee joint is installed. 1 is a schematic side view showing a tibia and a femur partially cut away. FIG. It is a side view explaining the usage method of the conventional artificial knee joint installation jig when a knee exists in an extended position. It is a side view explaining the usage method of the conventional artificial knee joint installation jig when a knee exists in a bending position.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Jig for artificial knee joint installation 2 Femur attachment member 4 Jig main body 12 Spacer 14 Movable block 14a Lower surface 16 Handle 18 Spacer main body 18b Upper surface 20 Additional spacer 26 Bracket 28 Pin 30 Insertion hole

Claims (6)

An artificial knee joint placement jig used when the knee is in a flexed position,
A femoral attachment member attached to the femur;
A jig body that abuts the proximal end surface of the tibia and the distal end surface of the femur formed by resection, and
The femoral attachment member and the jig main body are movable relative to each other in a direction perpendicular to the proximal end surface of the tibia in order to generate a predetermined tension state in the ligament that connects the tibia and the femur, and at an arbitrary relative position. Can be locked together with each other,
The jig body indicates a guide hole for forming an installation reference hole common to artificial knee joints of different sizes on the distal end surface of the femur and an anterior installation surface of the femur corresponding to artificial knee joints of different sizes. And an artificial knee joint placement jig characterized by comprising: The jig body includes a spacer disposed on a proximal end surface of the tibia, and a movable block that is removably coupled to the spacer and abuts against a distal end surface of the femur.
The femoral attachment member and the movable block are connected to each other so as to be movable relative to each other in a direction perpendicular to the proximal end surface of the tibia and to be locked at an arbitrary relative position. Jig for artificial knee joint installation.   The spacer has an upper surface that contacts the movable block, a bracket extending upward from the upper surface, and a pin extending in parallel with the upper surface and in the front-rear direction from the bracket, and the movable block includes an upper surface of the spacer body. The lower surface which contacts, The insertion hole which inserts the said pin in a fitting state in the state which this lower surface and the upper surface of the said spacer main body contact | abutted is provided. Jig for artificial knee joint placement.   The artificial knee joint installation jig according to any one of claims 1 to 3, wherein the instruction unit has a scale for indicating the front installation surface of the artificial knee joints having different sizes.   The artificial knee joint installation jig according to any one of claims 1 to 4, wherein the instruction unit includes a plurality of guide surfaces aligned with the front installation surfaces of artificial knee joints having different sizes.   The artificial knee joint installation jig according to any one of claims 1 to 5, wherein the jig body further includes a handle.

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