JP2012040150A - Osteotomy pretreatment tool before artificial knee joint replacement - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an osteotomy pretreatment tool which enables a surgeon to confirm the amount of respective bones to be cut quickly, accurately, and easily before the osteotomy for forming the front side surface and the rear side surface at the distal end of a femur during surgery of artificial knee joint replacement, and facilitates osteotomy afterward.SOLUTION: The osteotomy pretreatment tool 1 is used before performing the osteotomy for forming the front bone cutting surface Ab and the rear bone cutting surface Ac of the distal end A2 of the femur for replacing a knee joint K with an artificial knee joint T. The osteotomy pretreatment tool 1 includes at least a gap block 10. The gap block 10 is placed on a proximal end surface Ba of a tibia cut perpendicularly to the functional axis Wb of a tibia B and abuts on the back A33 of the medial condyle and the back A43 of the lateral condyle of the femur A in a flexed position. Then, the gap block 10 keeps a posterior condyle axis Lx passing through the back A33 of the medial condyle and the back A43 of the lateral condyle of the femur A in the flexed position in a state to internally rotate with respect to the proximal end surface Ba of the tibia.

Description

  The present invention relates to an osteotomy pretreatment jig used before performing osteotomy of a distal femur in order to replace a knee joint with an artificial knee joint.

  When replacing a knee joint with an artificial knee joint, an optimal fit for the knee joint from among multiple knee prosthetic knee joints based on fluoroscopic images obtained by an X-ray transmission imaging device or CT tomography device The one with the right dimensions is selected. In addition, a portion of the distal femur and a portion of the proximal tibia are each resected to fit the selected knee prosthesis. At that time, various techniques exist for the osteotomy method and the adjustment method of the tension of the medial collateral ligament and the lateral collateral ligament.

  The proximal tibia is osteotomized by an oscillating cutting tool (bone saw) that is inserted into the slot of the resection guide set in the tibia. By this osteotomy, an osteotomy surface (proximal surface of the tibia) perpendicular to the functional axis of the tibia is formed at the proximal tibia. The distal femur is osteotomized by a bone saw that is inserted into a slot in a dedicated resection guide set in the femur. At this time, first, an osteotomy surface (distal surface of the femur) perpendicular to the functional axis of the femur is formed. Further, another resection guide is attached to the formed distal surface of the femur, and the anterior surface and the posterior surface, and the anterior inclined surface and the posterior inclined surface provided between the distal surface, the anterior surface and the posterior surface, respectively. Four faces of the face are formed by osteotomy.

  Osteotomy at the distal femur should be performed so that the tension balance between the medial collateral ligament and the lateral collateral ligament in the extended and bent positions of the knee joint after the artificial knee joint is attached is approximately equal. Is preferred.

  For example, after adjusting the tension of the medial collateral ligament and lateral collateral ligament so that the functional axes of the femur and tibia are linear in the extended position, the amount of osteotomy in the bent position is adjusted, and the extended position and the bent There is a technique to balance the tension of the position. An artificial knee joint installation jig used in this procedure of bone cutting is described in Patent Document 1.

  The jig includes a spacer placed on the osteotomy proximal to the tibia, a movable block connected to the cylindrical portion of the femoral attachment member attached to the femur and removably fixed to the spacer. have. The movable block incorporates a drive screw, and the femoral attachment member is moved relative to the spacer by operating the drive screw. That is, the distal femur is displaced in a direction perpendicular to the osteotomy surface of the tibia. Thereby, the tension | tensile_strength of the outer side collateral ligament of a bending position and the inner side collateral ligament is made to correspond with the tension | tensile_strength of an extension position. Then, an osteotomy blade is inserted along the guide surface of the support portion provided on the movable block to form a front installation surface (anterior surface) distal to the femur.

  In addition, perform osteotomy at an angle determined in advance by an examination before surgery, etc., and loosen or scrape the soft tissue including the medial collateral ligament and lateral collateral ligament. There are techniques to balance the tension of the collateral ligament and the lateral collateral ligament. In this technique, a femoral dimension measuring device and a cutting block used for osteotomy of the distal femur are described in Patent Document 2.

  The femur dimension measuring device is attached to a reamer rod inserted into the intramedullary canal from the distal femur. The size of the artificial knee joint (prosthesis) adapted to the distal femur is determined by reading from the scale displayed on the femoral dimension measuring device attached to the distal femur before the osteotomy. The cutting block has each slot which can form five surfaces of the femur distal surface, anterior surface, posterior surface, anterior inclined surface, and posterior inclined surface once attached to the distal femur. Yes. According to Patent Document 2, the cutting block is commonly used regardless of the size of the artificial knee joint, and selectively uses only one of the anterior reference and the posterior reference with respect to the femur.

JP 2007-75517 A Japanese Patent Publication No. 11-504532

  By the way, with respect to knee joints having different dimensions and shapes for individuals, artificial knee joints prepared for replacing the knee joints are only prepared in several sizes. Therefore, an artificial knee joint having an optimal size slightly deviating from the ideal size will be replaced. The femoral component of the knee prosthesis is mounted so as to cover the distal femur from the front to the back. Therefore, even if the anterior osteotomy surface distal to the femur is formed in an optimal state with respect to the selected artificial knee joint, if the posterior osteotomy surface is out of the acceptable tolerance range, an artificial knee joint of that size should be used. In some cases, it cannot be adopted.

  Therefore, as in Patent Document 1, adjustment is made so that the tensions of the medial collateral ligament and the lateral collateral ligament match in the extended position and the bent position, and osteotomy is performed along the anterior osteotomy surface at the distal femur. However, it is not known whether the amount of osteotomy on the posterior osteotomy surface of the medial and lateral condyles of the femur is compatible with the femoral component of the selected knee prosthesis. Moreover, even if an artificial knee joint having a size that fits by measuring the distal femur so as to sandwich the anterior osteotomy surface and the posterior osteotomy surface as in Patent Document 2, the cutting block is selected from the anterior reference or posterior. If mounting is biased toward the reference, the dimensional difference will appear biased in either direction.

  Anatomically, the joint surface of the knee joint is not provided at right angles to the functional axes of the femur and tibia and is inclined about 3 ° outward with respect to the functional axis of the tibia, although there are individual differences. . In contrast, in knee replacement surgery, the proximal tibia and distal femur are used as functional axes in consideration of load transmission between the knee prosthesis and the tibia and femur and long-term stability. Osteotomy is performed along a plane perpendicular to the surface. Therefore, in order to offset the articular surface inclination in the flexion position by cutting the proximal tibia perpendicular to the functional axis, the femoral component is There is a technique to attach it by rotating it about 3 °.

  Also, it passes through the attachment part where the medial collateral ligament adheres to the medial epicondyle of the femur and the attachment part where the lateral collateral ligament adheres to the epicondylus lateralis. The condylar axis (transepicondyla axis) is an angle rotated about 4 to 7 ° with respect to the functional axis of the femur, although there are individual differences. Therefore, in order to cancel out the inclination of the joint surface, if the femoral component is attached by rotating it about 3 ° outward from the posterior condylar axis passing through the posterior medial and posterior condyles, the flexion and extension of the externally rotated femoral component The axis does not coincide with the transcondylar axis. As a result, the tension of the medial collateral ligament and the lateral collateral ligament is not constant between the extended position and the bent position, and the movement of the knee joint is not smooth.

  In order to balance the tension of the medial collateral ligament and the lateral collateral ligament, the osteotomy surface of the femur and the osteotomy surface of the tibia must be parallel in both the extended and bent positions. is there. There is a technique for balancing the tension of the medial collateral ligament and the lateral collateral ligament by releasing a part of the soft tissue of the ligament after osteotomy. However, too much incision may loosen the knee joint. Therefore, in order to avoid the need to open the soft tissue as much as possible in the artificial knee joint replacement operation, it is necessary that each osteotomy surface of the femur be parallel to the proximal surface of the tibia in both the extended position and the bent position. I want to be able to cut bone after confirming before cutting the distal femur.

  Even in an ideal knee joint, the flexion and extension axes of the femur and tibia are not constant and do not coincide with the transcondylar axis. Thus, these axial misalignments are absorbed by soft tissue such as the ligaments surrounding the knee joint and the meniscus between the femur and the tibia. When the knee joint is replaced with an artificial knee joint, the soft tissue is replaced with metal, hard resin, or the like, so that the displacement between the flexion / extension axis and the transcondylar axis cannot be sufficiently absorbed.

  For this reason, in an artificial knee joint replacement operation, it is desirable to be able to confirm the exact amount of osteotomy during the operation so that the flexion and extension axis of the artificial knee joint is as close as possible to the transcondylar axis. In addition, in order to reduce the burden on the patient due to surgery, the artificial bones of the appropriate size should be preserved as much as possible to preserve as much bone as possible in the existing knee joint and the amount to be resected by osteotomy should be minimized. I want to be able to select the knee joint.

  Therefore, the present invention can quickly and accurately confirm the amount of each osteotomy before osteotomy for forming an anterior osteotomy surface and a posterior osteotomy surface distal to the femur in an artificial knee joint replacement operation. In addition, the osteotomy pretreatment jig that makes it easy to perform subsequent osteotomy is provided.

  The osteotomy pretreatment jig according to the present invention is used before performing osteotomy for forming an anterior osteotomy surface and a posterior osteotomy surface distal to the femur in order to replace the knee joint with an artificial knee joint. This osteotomy pretreatment jig includes at least a gap block. This gap block is placed on the proximal surface of the tibia, which is cut perpendicular to the functional axis of the tibia, and contacts the posterior medial and posterior condyles of the flexed femur. The gap block holds the posterior condylar axis passing through the medial posterior and posterior lateral condyles of the femur in the bent position in a state of being internally rotated with respect to the proximal surface of the tibia. In this case, the gap block has the posterior condylar axis relative to the proximal tibia to such an extent that the transcondylar axis passing through the attachment of the medial and lateral collateral ligaments to the femur is parallel to the proximal tibia. It is configured so as to be held in an internally rotated state.

  Alternatively, the osteotomy pre-processing jig includes a gap block, a movable main body, a mark, a gap scale, and an osteotomy scale. The movable body is positioned relative to the proximal end of the anterior osteotomy surface distal to the femur. The proximal end of the anterior osteotomy depends on the size of the knee prosthesis prepared in different sizes in multiple stages. The movable main body has a guide hole indicating a position where the peg hole is formed. The peghole is a hole used to place the femoral component of the knee prosthesis at the distal femur. The mark is attached to a mark attachment portion provided on the movable main body and displays a posterior osteotomy surface distal to the femur. The mark attachment portion is provided corresponding to the size of the artificial knee joint selected when positioning the movable main body. The gap scale has a scale indicating the distance from the proximal surface of the tibia to the posterior osteotomy surface distal to the femur. The osteotomy scale has scales that respectively display the distance from the femoral medial posterior condyle and lateral posterior condyle in a direction perpendicular to the posterior osteotomy plane indicated by the mark.

  Moreover, the osteotomy pretreatment jig of another form is further provided with a base plate and a caliper. The base plate is attached to the distal femur formed on the medial and lateral condyles of the femur perpendicular to the functional axis of the flexed femur placed on the gap block. The caliper points to the proximal end of the anterior osteotomy surface that is formed when the anterior part of the distal femur is osteotomized, fixed to the movable body. At this time, the movable body is slidably fitted to the base plate parallel to the distal surface of the femur. The osteotomy scale includes an osteotomy scale for the medial condyle having a scale indicating the distance from the posterior osteotomy surface to the posterior medial condyle, and an external condyle having a scale indicating the distance from the posterior osteotomy surface to the lateral posterior condyle. Including an osteotomy scale. The mark displays the distance from the proximal tibia to the distal posterior osteotomy on the distal femur on the gap scale, the posterior osteotomy amount of the medial condyle on the osteotomy scale for the medial condyle, and lateral The amount of posterior osteotomy of the condyle is displayed on the osteotomy scale for the lateral condyle.

  The gap block is an upper surface that is inclined with respect to the proximal surface of the tibia by an angle corresponding to the angle at which the transcondylar axis (transepicondyla axis) is rotated with respect to the functional axes of the femur and tibia. Have Alternatively, the gap block has an upper surface that is inclined with respect to the proximal surface of the tibia by an angle corresponding to an angle formed by the transcondylar axis and the posterior condylar axis.

  Here, “transepicondylar axis” means the axis passing through the part where the medial collateral ligament adheres to the medial epicondyle of the femur and the part where the lateral collateral ligament adheres to the lateral epicondyle To do. “Functional axis” means an axis that passes from the center of the head of the bone to the center of the rib joint in the extended position through the center of the knee joint. In addition, the “posterior condyle axis” means an axis that passes through the medial posterior and lateral posterior condyles of the femur.

  Further, the movable main body has a mark attachment portion for attaching the mark in one-to-one correspondence with the size of the artificial knee joint. The caliper has a mark for positioning on the movable body in one-to-one correspondence with the size of the artificial knee joint.

  One caliper is selected from the caliper for the outside, the caliper for the inside, and the caliper for the center. The caliper for the outside is fixed to the upper end of the movable body on the lateral condyle side of the femur, and wraps around the lateral condyle to contact the proximal end of the anterior osteotomy surface. The medial caliper is fixed to the upper end of the movable body on the medial condyle side of the femur, and wraps around the medial condyle and abuts on the proximal end of the anterior osteotomy surface. The center caliper is fixed to the central upper end of the movable body facing the part between the lateral and medial condyles of the femur and passes the patella surface of the femur from the front side to the proximal end of the anterior osteotomy surface. Touch.

  Further, the osteotomy scale for the medial condyle and the osteotomy scale for the lateral condyle include a stem, a scale block, and a fixture. The stem moves parallel to the lower surface of the gap block. The scale block is provided with a scale, and is attached to the stem so as to be movable perpendicularly to the lower surface of the gap block. The fixing tool fixes the scale block to the stem. In order to improve operability, the stem is mounted in a slot provided in the gap block parallel to the lower surface of the gap block. The osteotomy scale for the medial condyle and the osteotomy scale for the lateral condyle further include a moving screw that moves the stem along the slot.

  Alternatively, the gap block has a slot provided in parallel to the inclined upper surface. The osteotomy scale for the medial condyle and the osteotomy scale for the lateral condyle include a stem, a scale block, a fixing tool, and a moving screw. The stem is mounted in the slot and moves along the slot. The scale block is provided with a scale, and is attached to the stem so as to be rotatable along a plane perpendicular to the upper surface and the lower surface of the gap block. The fixing tool fixes the scale block to the stem. The moving screw moves the stem along the slot.

  Alternatively, the osteotomy scale for the medial condyle and the osteotomy scale for the lateral condyle are attached to the mark so as to be movable along the posterior osteotomy line marked on the femur.

  In addition, the mark includes a central window, an inner window, and an outer window in order to make the display portion easy to see. The central window is opened to show the gap scale scale from the front. The medial window opens so that the scale of the osteotomy scale for the medial condyle can be seen from the front. The lateral window is opened so that the scale of the osteotomy scale for the lateral condyle can be seen from the front.

  The osteotomy pretreatment jig of the present invention includes a gap block and is used before osteotomy to form an anterior osteotomy surface and a posterior osteotomy surface distal to the femur in an artificial knee joint replacement operation. The flexed femur can be internally rotated with respect to the proximal surface of the tibia at an angle corresponding to the angle at which the transcondylar axis rotates outwardly with respect to the functional axis. Therefore, it is easy to adjust the tension of the inner collateral ligament and the outer collateral ligament in the extended position and the bent position.

  Further, according to the osteotomy pretreatment jig further provided with the movable main body, the mark, the gap scale, and the osteotomy scale, it is possible to quickly and accurately check the osteotomy amount. As a result, the angle at which the femoral component is rotated relative to the distal femur can be adjusted so that the flexion and extension axis of the artificial knee joint approaches the transcondylar axis passing through the attachment part of the medial collateral ligament and the lateral collateral ligament. The opportunity to change the artificial knee joint selected before the operation to a suitable size can be obtained. And since it has a guide hole for drilling a peg hole as a reference for mounting a bone cutting guide jig etc. for performing subsequent bone cutting, check that the amount of femoral bone cutting is optimal In addition, a peg hole can be provided.

  Thus, during the artificial knee joint replacement operation, the amount of osteotomy at the distal femur can be accurately confirmed before the osteotomy, and the subsequent osteotomy can be performed smoothly. As a result, the operation time can be shortened, and the burden on the patient and the burden on the practitioner can be reduced.

The disassembled perspective view which shows the osteotomy pretreatment jig | tool of the 1st Embodiment of this invention. The front view which shows the functional axis set to the femur and tibia of a left leg. The perspective view which shows the relationship between the knee joint of a left leg and the transcondylar axis. The perspective view which shows the knee joint of the left leg of the bending position to which the artificial knee joint was mounted | worn. FIG. 2 is a front view of a state in which the gap block of the osteotomy pretreatment jig illustrated in FIG. The perspective view of the state which mounted | wore the gap block shown in FIG. 5 with the drill guide for baseplate fixing holes. FIG. 7 is a perspective view just before the drill guide shown in FIG. 6 is removed and the base plate is attached to the distal femur. The perspective view just before mounting | wearing a movable main body with the base plate shown in FIG. The perspective view which expanded the fixing | fixed part of the caliper fixed to the movable main body shown in FIG. FIG. 9 is a side view showing a state where a movable main body is mounted on the base plate shown in FIG. 8. FIG. 11 is a front view of a state in which a gap scale is attached to the gap block shown in FIG. 10 and a mark is attached to the movable main body. The perspective view of the state in which the osteotomy scale for lateral condyles was mounted on the gap block of the osteotomy pretreatment jig shown in FIG. The front view of the state in which the osteotomy scale for medial condyles and lateral condyles was attached to the gap block shown in FIG. The front view of the state which mounted | wore the movable main body shown in FIG. 13 with the mark. The perspective view which shows a part of osteotomy pretreatment jig | tool with which the caliper for centers was mounted instead of the caliper for outer side. The disassembled perspective view which shows the fixed part of the movable main body and caliper of the osteotomy pretreatment jig | tool of the 2nd Embodiment of this invention in a partial cross section. The front view which shows the mark of the pre-bone cutting processing jig of the 3rd Embodiment of this invention, and its periphery. The disassembled perspective view which shows the gap block of the osteotomy pretreatment jig | tool of the 4th Embodiment of this invention, and the osteotomy scale for medial condyles and external condyles with which this is mounted | worn. FIG. 19 is a cross-sectional view of the osteotomy scale for the lateral condyle shown in FIG. 18 and its surroundings. Sectional drawing in case the moving screw of the osteotomy scale for lateral condyles shown in FIG. 19 is a reverse screw. The disassembled perspective view which shows the osteotomy scale for medial condyles and the external condyles with the mark of the osteotomy pretreatment jig | tool of the 5th Embodiment of this invention. The disassembled perspective view which shows the osteotomy scale for medial condyles and lateral condyles attached to the gap block of the osteotomy pretreatment jig | tool of the 6th Embodiment of this invention.

  The osteotomy pretreatment jig 1 according to the first embodiment of the present invention will be described with reference to FIGS. Further, in the present embodiment, the osteotomy pretreatment jig 1 for the knee joint of the left leg will be described as an example. The osteotomy pre-processing jig for the knee joint of the right leg is the same as that of the present embodiment in which the left and right sides are reversed, and thus the description thereof is omitted here.

  In this specification, “distal” indicates a direction away from the trunk of the human body, and “proximal” indicates a direction toward the trunk attachment portion of the limb. “Front” and “rear” indicate the front side and the rear side in an upright posture. “Outside” indicates a direction away from the median plane of the human body, and “inside” indicates a direction approaching the median plane.

  When the knee joint K shown in FIGS. 2 and 3 is replaced with the artificial knee joint T shown in FIG. 4, the distal femur A2 and the proximal tibia B1 are osteotomized, respectively. At this time, as shown in FIG. 2, the functional axis W that passes from the center of the femoral head A1 through the middle of the knee joint K and penetrates the rib D is in its original position, that is, is adjusted to be in a straight line. A load corresponding to the weight is applied to the knee joint K while standing. In order to prevent the load acting on the knee joint K in the extended position Pe from being biased, the proximal tibia B1 is cut perpendicular to the functional axis Wb of the tibia B to form the proximal tibia surface Ba, The distal femur A2 is cut perpendicular to the functional axis Wa of the femur A to form the distal femur Aa. Then, the femur A and the tibia B are arranged so that the functional axes Wa and Wb of the femur A and the tibia B coincide with each other, that is, the femur distal surface Aa and the tibia proximal surface Ba are parallel to each other. Is placed.

  As shown in FIG. 4, the femoral component T1 of the artificial knee joint T is attached to the distal femur A2 so as to cover the range from the front to the rear along the bending direction of the knee joint K. Therefore, the distal femur A2 forms a chamfer by cutting the anterior osteotomy surface Ab, the posterior osteotomy surface Ac, and the corners therebetween in addition to the femur distal surface Aa.

  The femoral component T1 is made so that the thickness of the member covering the distal femur A2 is substantially uniform. Therefore, the bending gap between the posterior osteotomy surface Ac and the tibia proximal surface Ba in the bending position Pf is different from the extension gap between the femoral distal surface Aa and the tibia proximal surface Ba in the extending position Pe. The bone should be cut to approximately the same dimensions.

  When bone deformation occurs in the knee joint K, the proximal tibia Ba and the distal femur Aa in the extended position Pe are provided perpendicular to the functional axis W, so that the knee joint K The angle of the joint surface, the rotation axis, the tension of the inner collateral ligament L1 and the outer collateral ligament L2, and the like may change before and after the operation. In such a case, the tensions of the inner collateral ligament L1 and the outer collateral ligament L2 are adjusted. In this embodiment, the description will be continued on the assumption that the tensions of the inner collateral ligament L1 and the outer collateral ligament L2 are balanced.

  In this embodiment, by adjusting the attachment angle of the femoral component T1 of the artificial knee joint T using the osteotomy pretreatment jig 1, the inner collateral ligament L1 and the outer side of the knee joint K in the bent position Pf are adjusted. The tension of the collateral ligament L2 is set to be the same as the tension of the extension position Pe. Specifically, as shown in FIG. 3, the medial attachment portion A32 and the lateral epicondyle (epicondylus) where the medial collateral ligament L1 adheres to the medial epicondyle (epicondylus medialith) A31 of the distal femur A2. Lateral) A transcondylar axis Lx passing through the outer attachment portion A42 where the outer collateral ligament L2 is attached to A41 is only an angle corresponding to an angle at which the external rotation R1 is made with respect to the functional axis Wa of the femur A as shown in FIG. The femoral component T1 of the artificial knee joint T is attached with the external rotation R2 as shown in FIG. 2 and 4 to 15, the inner collateral ligament L1 and the outer collateral ligament L2 are omitted.

  This osteotomy pretreatment jig 1 is used when the femoral component T1 is attached with an external rotation R2 around the functional axis Wa of the femur A by an arbitrary angle R2 and the anterior osteotomy surface Ab and the posterior bone of the femur A Used to confirm the amount of osteotomy of the cut surface Ac. The osteotomy pre-processing jig 1 is formed before the osteotomy of the anterior osteotomy surface Ab and the posterior osteotomy surface Ac of the distal femur A2 after the distal femur distal surface Aa and the proximal tibia Ba are formed. Used for.

  As shown in FIG. 1, the osteotomy pretreatment jig 1 includes a gap block 10, a base plate 20, a movable body 30, a caliper 40, a gap scale 50, and an osteotomy scale 601 for the medial condyle A3. An osteotomy scale 602 for the lateral condyle A4 and a mark 70 are provided.

  As shown in FIGS. 1 and 5, the gap block 10 is installed on the proximal tibia Ba of the bending position Pf. The gap block 10 is fixed with a peg or an anchor pin so as not to move during the treatment. In order to attach the femoral component T1 to the femur A in the bent position Pf as shown in FIG. 4, the gap block 10 attaches the femur A to the proximal surface of the tibia Ba as shown in FIG. The upper surface 11 is inclined in the direction of internal rotation. That is, the upper surface 11 is inclined inward.

  Thus, when the medial condyle posterior A33 of the medial condyle A3 and the lateral posterior condyle A43 of the lateral condyle A4 of the femur A are brought into contact with the upper surface 11 of the gap block 10, the femur A is in contact with the proximal tibia Ba. It will be in a state of internal rotation. The inclination angle 11a of the upper surface 11 of the gap block 10 is set so as to be substantially the same as the angle at which the transcondylar axis Lx rotates outward with respect to the femur A. The rear central portion of the gap block 10 is cut away so as not to interfere with the anterior cruciate ligament and the posterior cruciate ligament when the gap block 10 is installed on the proximal tibia Ba.

  As shown in FIG. 1, several types of gap blocks 10 with different angles are prepared in accordance with the angle at which the transcondylar axis Lx is set. A gap block 10 having an appropriate inclination angle 11a is selected based on information confirmed in advance by the X-ray diagnostic apparatus. Further, the spacer 101 shown in FIG. 1 is attached to the tibia so that the tension of the medial collateral ligament L1 and the external collateral ligament L2 is substantially the same in the extended position Pe as shown in FIG. 2 and the bent position Pf shown in FIG. It may be inserted between the proximal face Ba and the gap block 10. In some cases, it is necessary to adjust the tension by adjusting soft tissues such as the inner collateral ligament L1 and the outer collateral ligament L2.

  As shown in FIG. 7, the base plate 20 is installed on the femoral distal surface Aa provided on the medial condyle A3 and the lateral condyle A4 of the femur A. The angle of flexion between the femur A and the tibia B is based on the lower surface 12 of the gap block 10 sandwiched between the tibia proximal surface Ba and the medial posterior condyle A33 and lateral posterior condyle A43 of the femur distal A2. This can be confirmed by the angle of the base plate 20 to be performed.

  The base plate 20 includes guide pins 21, a fixing hole 22, and a slide guide 23. The guide pin 21 is fitted into a mounting hole Ad provided on the distal femur Aa as shown in FIG. The attachment hole Ad is formed by the drill guide 102 shown in FIG. The drill guide 102 is fitted into the central slot 13 provided in the gap block 10. The attachment holes Ad formed in the medial condyle A3 and the lateral condyle A4 are provided at the same distance from the tibia proximal surface Ba. The fixing hole 22 is provided obliquely with respect to the femoral distal surface Aa, and fixes the base plate 20 so as not to easily float from the femoral distal surface Aa by mounting an anchor pin. The slide guide 23 protrudes on the surface opposite to the guide pin 21 and extends perpendicularly to the proximal tibial surface Ba, that is, the lower surface 12 of the gap block 10.

  As shown in FIGS. 1 and 8, the movable main body 30 has a groove 31, a caliper fixing portion 32, a guide hole 33, and a mark attachment portion 34. As shown in FIG. 8, the groove 31 is provided on the side facing the distal femur Aa and fits with the slide guide 23 of the base plate 20. The caliper fixing portions 32 are respectively provided at positions facing the three locations of the outer side, the inner side, and the central portion near the front of the femur A. One guide hole 33 is provided on each outer side of the groove 31, and indicates the position of the peg hole Ta drilled in the distal femur Aa of the medial condyle A3 and the distal femur Aa of the lateral condyle A4. Yes. The peg hole Ta is a mounting hole for fixing the femoral component T1 of the artificial knee joint T. After the amount of osteotomy is confirmed, a drill is inserted into this guide hole 33, and the peg hole Ta is processed into the femur distal surface Aa. The mark attaching portion 34 is provided for attaching the mark 70 as shown in FIGS. 11 and 14, and is shown corresponding to each size of the artificial knee joint T in which different sizes are prepared in a plurality of stages. As shown in FIG. 1 and FIG.

  In this embodiment, the caliper 40 is fixed to the caliper fixing portion 32 on the outer side of the movable main body 30 with screws 401 as shown in FIGS. 1 and 8 to 11. The caliper 40 includes a base portion 41 and an arm portion 42. The base 41 has a structure that can move in a direction perpendicular to the femoral distal surface Aa, and is fastened with a screw 401 to be fixed at an arbitrary position. The base portion 41 is engraved with a number 43 and positioning marks 44 corresponding to the artificial knee joints T having different sizes in a plurality of stages. The base 41 is fixed in accordance with the surface 44 of the movable body 30 facing the base plate 20 with the mark 44 of the number 43 of the size of the selected artificial knee joint T in the same manner as the mark 70 is mounted. The mark 44 is inscribed above the number 43.

  In the present embodiment, a case where the size of the artificial knee joint T selected in advance is “2” will be described as an example. The caliper 40 shown in FIGS. 9 and 10 is aligned with the mark 44 of the number “2”. The arm portion 42 is provided integrally with the base portion 41, and turns around the outer side condyle A <b> 4 of the femur A so that the edge 421 near the movable main body 30 abuts on the anterior side A <b> 21 of the femoral distal A <b> 2. The position where the edge 421 of the arm portion 42 abuts on the front A21 of the femur A indicates the proximal end Ab1 of the anterior osteotomy surface Ab formed when the front osteotomy of the distal femur A2 is performed. Yes. The arm portion 42 is provided at an angle along the front osteotomy surface Ab. Therefore, as shown in FIG. 10, when viewed from the outside of the femur A, the anterior osteotomy surface Ab is indicated by the arm portion 42. As shown in FIG. 10, the caliper 40 makes the guide hole 33 of the movable main body 30 to the femoral distal surface Aa in a state where the tip of the arm portion 42 is in contact with the front A21 of the femoral distal A2. Position it.

  As shown in FIGS. 1, 11, and 13, the gap scale 50 is attached to the central slot 13 provided in the central portion of the gap block 10. The scale portion 51 of the gap scale 50 extends perpendicularly to the lower surface 12 of the gap block 10, and the posterior osteotomy surface Ac from the proximal tibia Ba to the distal femur A 2 with respect to the lower surface 12 of the gap block 10. A scale 52 for displaying the distance up to is engraved in units of 1 mm. The interval between the scales 52 may be 0.5 mm, and is not limited to 1 mm. Further, the scale 52 is provided long in the width direction of the scale portion 51 every 5 mm.

  As shown in FIGS. 1 and 12, the osteotomy scale 601 for the medial condyle A3 and the osteotomy scale 602 for the lateral condyle A4 include a stem 61, a scale block 62, a fixing tool 63, and a moving screw 64. Prepare each. The stem 61 has a base 611 inserted in slots 141 and 142 formed in parallel to the lower surface 12 of the gap block 10, and is movable in the width direction. The scale block 62 is placed on the guide 612 of the stem 61 that extends perpendicularly to the lower surface 12 of the gap block 10, and the scale 621 that can be seen from the same direction as the scale 52 of the gap scale 50 is engraved in units of 1 mm. ing. The fixing tool 63 is a screw attached to a screw hole 622 that passes through the scale block 62 toward the guide 612 of the stem 61, and the scale block 62 is fixed to the stem 61 at an arbitrary position by tightening. be able to. The osteotomy scale 601 for the medial condyle A3 displays the reference line 623 of the scale block 62 to indicate the distance from the upper surface 11 of the gap block 10 to the posterior osteotomy surface Ac of the medial condyle A3 of the femur A. Fix to the upper surface 11 of the gap block 10 on the A3 side. The osteotomy scale 602 for the lateral condyle A4 displays the reference line 623 of the scale block 62 to indicate the distance from the upper surface 11 of the gap block 10 to the posterior osteotomy surface Ac of the lateral condyle A4 of the femur A. Fix to the upper surface 11 of the gap block 10 on the A4 side. The moving screw 64 is engaged with a rack 613 formed on the base 611 of the stem 61 and rotates to move the stem 61 along the slots 141 and 142 together with the scale block 62.

  In the mark 70, an osteotomy line 71 indicating the posterior osteotomy surface Ac of the femur A is marked over the entire length in the width direction, and is attached to one of the mark attachment portions 34 of the movable body 30. In this embodiment, since the case where the size of the artificial knee joint T selected in advance is “2” is described as an example, the mark 70 is “2” displayed on the movable main body 30 in FIG. It is attached to a mark attachment portion 34 provided next to the number 35. That is, the mark 70 is attached to the mark attachment portion 34 having the same number 35 as the mark 44 to which the base portion 41 of the caliper 40 is aligned. The mark 70 attached to the mark attachment portion 34 of “2” indicates the posterior osteotomy surface of the distal femur A2 for attaching the femoral component T1 when the artificial knee joint T of size “2” is selected. The position of Ac is displayed. Further, as shown in FIG. 14, the mark 70 displays the gap from the proximal tibia Ba to the posterior osteotomy surface Ac of the distal femur A2 on the gap scale 50, and the posterior osteotomy of the medial condyle A3. The amount is displayed on the osteotomy scale 601 for the medial condyle A3, and the posterior osteotomy amount of the lateral condyle A4 is displayed on the osteotomy scale 602 for the lateral condyle A4. When an artificial knee joint T of another size is selected, the mark 70 is attached to the mark mounting portion 34 on which the size number 35 is displayed next. For example, when the artificial knee joint T of size “3” is selected, the mark 70 is attached to the mark attachment portion 34 on which the number 35 “3” is displayed next. At this time, the caliper 40 is also attached to the movable main body 30 according to the mark 44 of the number 43 of the selected size.

  The osteotomy pretreatment jig 1 configured as described above is used before the anterior osteotomy surface Ab and the posterior osteotomy surface Ac of the distal femur A2 are actually formed. It is possible to know in detail how much the amount of cut is, and how much the gap between the proximal surface of the tibia Ba and the posterior osteotomy surface Ac of the distal femur A2 at the bending position Pf is. Then, since the amount of osteotomy on both the front side and the rear side of the femur A and the gap after osteotomy in the extended position Pe and the bent position Pf are known, the balance between them can be confirmed. In addition, it is possible to confirm whether there is a possibility that the size next to the artificial knee joint T selected in advance may be more suitable by simply changing the mounting position of the caliper 40 and the mark 70. When the amount of osteotomy is confirmed and the size of the artificial knee joint T to be applied is determined, the peg hole Ta is formed using the guide hole 33 provided in the movable main body 30.

  By the way, when the caliper 40 interferes with an incised surgical field or an instrument attached to the periphery, the caliper 40 for the center shown in FIG. 15 is used. The center caliper 40 is attached to a caliper fixing portion 32 provided at the center of the movable main body 30. The caliper 40 includes a base 41, an arm portion 42, and a raising base 45. Similar to the caliper 40 for the outside, the base 41 is engraved with a number 43 indicating the size of the artificial knee joint T and a mark 44 corresponding thereto. The base portion 41 is fixed to the caliper fixing portion 32 with a screw 402 with the raising base 45 interposed therebetween so that the bulges of the medial condyle A3 and the lateral condyle A4 of the distal femur A2 cross the patella surface A5 of the femur A from the front side. . The arm part 42 extends straight from the base part 41, and the tip is bent toward the femur A side. The tip of the arm portion 42 points to the proximal end Ab1 of the anterior osteotomy surface Ab of the femur A by an edge 421 closer to the femur distal surface Aa.

  If neither the outer caliper 40 nor the center caliper 40 interferes with the instrument or the like and cannot be used, the inner caliper 40 is used. The inner caliper 40 is fixed to an inner caliper fixing portion 32 provided at the inner upper end of the movable main body 30 facing the inner condyle A3 of the distal femur A2, and wraps around the inner condyle A3 and moves toward the anterior osteotomy surface. An edge 421 facing the movable body 30 abuts on the proximal end Ab1 of Ab. The caliper 40 for the inside is made symmetrically with the caliper 40 for the outside. The caliper 40 having the best workability may be selected from the caliper 40 for the outside, the caliper 40 for the inside, and the caliper 40 for the center according to the environment such as the surgical field.

  The caliper 40 shown in FIGS. 1, 8, 9, and 10 is an outer caliper 40 because it is applied to the left leg. When the osteotomy pretreatment jig is for the right leg, the inner caliper has the same shape as the outer caliper 40 of the left leg osteotomy pretreatment jig 1. Similarly, the caliper 40 for the inside of the osteotomy pre-processing jig 1 for the left leg can be used as a caliper for the outside of the osteotomy pre-processing jig for the right leg.

  The osteotomy pretreatment jig 1 configured as described above includes a gap block 10. The gap block 10 is placed on the proximal tibia surface Ba and supports the posterior medial condyle A33 and the lateral posterior condyle A43 of the flexed femur A, so that the flexed femur A is attached to the proximal tibia Ba. Is held in an internally rotated state.

  If the gap block 10 having the upper surface formed at an angle corresponding to the angle corresponding to the angle at which the transcondylar axis Lx is externally rotated with respect to the functional axis Wa of the femur is used, the transcondylar axis Lx is moved near the tibia. It can be arranged substantially parallel to the lateral surface Ba. As a result, the amount of osteotomy should be estimated and the size of the artificial knee joint T selected so that the tension on the medial collateral ligament L1 and the lateral collateral ligament L2 is the same in both the extended position and the flexion position. Can be easily performed.

  In this manner, since the osteotomy pretreatment jig 1 can be used to specifically confirm the amount of osteotomy before osteotomy, the subsequent osteotomy and the artificial knee joint T can be smoothly mounted. Can do. Therefore, since the operation time is shortened, the burden on the patient can be reduced and the burden on the operator who performs the operation can also be reduced.

  As described above, the osteotomy pretreatment jig 1 is used when osteotomy of the distal femur A2 is performed, so that the flexion / extension axis (rotation axis) of the artificial knee joint T is the transcondylar axis Lx of the femur A. Can be set to approach. As a result, the tension of the inner collateral ligament L1 and the outer collateral ligament L2 is expected to be stable from the extended position Pe to the bent position Pf. That is, since the artificial knee joint T can be held firmly and can be smoothly bent and extended, long-term stability can be expected.

  The osteotomy pretreatment jig 1 of the second to seventh embodiments according to the present invention will be described with reference to FIGS. 16 to 21. At this time, only a different part compared with the osteotomy pretreatment jig 1 of the first embodiment will be shown and described. Other configurations are the same as the osteotomy pretreatment jig 1 of the first embodiment, and therefore, the description and drawings of the first embodiment are referred to for details. Moreover, in the figure, the structure which has the same function as the osteotomy pretreatment jig 1 of the first embodiment is given the same reference numeral in the figure, and the description thereof is omitted.

  The movable main body 30 and caliper 40 of the osteotomy pretreatment jig 1 according to the second embodiment of the present invention are shown in FIG. The caliper fixing portion 32 of the movable main body 30 of the present embodiment is formed in a trapezoidal groove that extends toward the bottom portion 321, a so-called “groove”. The base portion 41 of the caliper 40 has a constricted portion 47 that fits into the caliper fixing portion 32 formed in the trapezoidal groove. The caliper 40 is mounted by being slid along the trapezoidal groove, and is fixed by a screw 403 that is disposed obliquely so that the tip contacts the constricted portion 47. By being configured in this way, the number 43 and the mark 44 indicating the size of the artificial knee joint T are not hidden by the hand operating the knob 404 of the screw 403. Therefore, the caliper 40 can be easily positioned. Further, since the screw 403 does not penetrate the base portion 41 of the caliper 40, the number 43 indicating the size of the artificial knee joint T can be displayed on the portion according to the position of the mark 44. This makes it easier to match the mark 44 to the size number 43.

  The mark 70 of the osteotomy pretreatment jig 1 according to the third embodiment of the present invention will be described with reference to FIG. The mark 70 has a central window 72, an inner window 73, and an outer window 74. The central window 72 is opened so that the scale 52 of the gap scale 50 can be seen from the front, and the position of the scale 721 marked in the center can be easily confirmed. The central window 72 is open to the extent that the number 35 of the mark mounting portion 34 to which the mark 70 is attached can also be seen. Therefore, it is easy to confirm the position where the mark 70 is attached.

  The medial window 73 opens so that the scale 621 of the osteotomy scale 601 for the medial condyle A3 can be seen from the front, and the lateral window 74 allows the scale 621 of the osteotomy scale 602 for the lateral condyle A4 to be seen from the front. Is open. Since the inner window 73 and the outer window 74 are opened larger than the width of the minor scale 621 of the osteotomy scale 601 for the medial condyle A3 and the osteotomy scale 602 for the lateral condyle A4, respectively, which position is indicated. It is easy to determine whether you are doing.

  The gap block 10 of the osteotomy pretreatment jig 1 according to the fourth embodiment of the present invention, the osteotomy scale 601 for the medial condyle A3, and the osteotomy scale 602 for the lateral condyle A4 are shown in FIGS. This will be described with reference to FIG. The gap block 10 is provided with slots 151 and 152 parallel to the inclined upper surface 11. The stems 61 of the osteotomy scale 601 for the medial condyle A3 and the osteotomy scale 602 for the lateral condyle A4 are inserted along the slots 151 and 152. The base portion 611 of the stem 61 has an engaging portion 614 that is partially swelled, and a screw hole 615 through which the moving screw 64 is passed is formed in the engaging portion 614. Accordingly, as shown in FIG. 19, the gap block 10 has an insertion hole 16 through which the engaging portion 614 passes along the slots 151 and 152.

  The head 616 of the stem 61 protruding from the slots 151 and 152 of the gap block 10 toward the front of the tibia B has a disk shape perpendicular to the lower surface 12 of the gap block 10 when viewed from the front of the tibia B. The scale block 62 is attached to the head 616, and is fixed by the fixture 63 so that the reference line 623 of the scale 621 coincides with the upper surface 11 of the gap block 10. Further, since the head 616 of the stem 61 has a disk shape, the scale block 62 is aligned perpendicularly to the lower surface 12 of the gap block 10 and fixed by the fixture 63 regardless of the inclination angle of the upper surface 11 of the gap block 10. can do.

  In the moving screw 64, an outer peripheral groove 641 in which the O-ring 65 is mounted is formed between the knob 642 and the screw portion 643. In addition, an inner peripheral groove 161 is formed in the insertion hole 16 of the gap block 10 at a position opposite to the outer peripheral groove 641. An O-ring 65 is attached to the outer circumferential groove 641 so that about half of the wire diameter protrudes from the groove. The moving screw 64 to which the O-ring 65 is attached is combined in a state where the moving screw 64 is screwed to the engagement portion 614 of the stem 61 to the middle. In this state, the stem 61 and the moving screw 64 are inserted into the slots 151 and 152 and the insertion hole 16 of the gap block 10, and the O-ring 65 is fitted into the inner peripheral groove 161 of the insertion hole 16. The O-ring 65 restricts the movement screw 64 from moving in the axial direction when the movement screw 64 is rotated in the U direction shown in FIG.

  The osteotomy scales 601 and 602 for the medial condyle A3 and the lateral condyle A4 of the osteotomy pretreatment jig 1 configured as described above are configured so that the stem 61 and the scale block 62 are rotated by turning the moving screw 64 in the U direction. Moves in the width direction indicated by the arrow So. When it is desired to remove the osteotomy scales 601 and 602 from the gap block 10, the osteotomy scales 601 and 602 can be pulled out of the gap block 10 by pulling the knob 642 of the moving screw 64. As described above, the osteotomy scale 601 for the medial condyle A3 and the osteotomy scale 602 for the lateral condyle A4 according to the present embodiment can be easily inserted and removed as necessary.

  Further, as shown in FIG. 20, it is also preferable to use a so-called reverse screw in which the screw pitch of the screw portion 643 of the moving screw 64 and the screw hole 615 of the engaging portion 614 is reversed from that in FIG. The direction in which the stem 61 and the scale block 62 advance when the moving screw 64 is rotated in the U direction is the direction indicated by the same arrow Si as the direction in which the screw advances in the axial direction when a normal screw is turned. Therefore, it is easy to understand intuitively for the operator, and the operability is improved. Since the position in the width direction is adjusted by turning the moving screw 64, the scale 621 can be adjusted with high accuracy. The configuration related to the moving screw 64 of the present embodiment can also be applied to the moving screw 64 of the first embodiment.

  The osteotomy scales 601 and 602 for the medial condyle A3 and the lateral condyle A4 of the osteotomy pretreatment jig 1 according to the fifth embodiment of the present invention will be described with reference to FIG. These osteotomy scales 601 and 602 are attached to the mark 70 as shown in FIG. The osteotomy scales 601 and 602 are used for confirming how much the medial condyle A3 and the lateral condyle A4 are removed when the osteotomy is performed along the posterior osteotomy surface Ac of the femur A. . Therefore, the osteotomy scales 601 and 602 of this embodiment are configured to measure the osteotomy amount with reference to the posterior osteotomy surface Ac.

  The osteotomy scales 601 and 602 include a scale block 62, a pressing piece 66, and a fixture 63. The scale block 62 is graduated in units of 1 mm with reference to the osteotomy line 71 marked on the mark 70, and extends vertically toward the gap block 10 side. The base 625 of the scale block 62 is cut into a wedge shape. The arm portion 75 of the mark 70 extending toward the medial condyle A3 and the lateral condyle A4 has a trapezoidal cross-sectional shape with the side facing the movable main body 30 as the base. The base 625 of the scale block 62 cut into a wedge shape matches the bottom surface 751 of the arm portion 75 of the mark 70 and one inclined surface 752. The pressing piece 66 has a through-hole 661 that matches the other inclined surface 753 of the arm portion 75 of the mark 70 and that is opened in the center. The fixing tool 63 is a screw, and the screw hole 626 of the base portion 625 of the scale block 62 is passed through the through hole 661 of the press piece 66 so that the arm portion 75 of the mark 70 is sandwiched between the press piece 66 and the base portion 625 of the scale block 62. Screwed into. The osteotomy scales 601 and 602 have no structural difference between the medial condyle A3 and the lateral condyle A4, and those having the same shape can be used.

  The osteotomy scales 601 and 602 of the osteotomy pretreatment jig 1 configured as described above can freely slide along the arm portion 75 of the mark 70 when the fixture 63 is loosened. Can be moved. Further, since the mark 70 is used as a reference, it is not necessary to move the position of the scale block 62 along the guide 612 of the stem 61 in order to adjust according to the gap block 10 in which the inclination angle of the upper surface 11 is different. The osteotomy pretreatment jig 1 of this embodiment can measure the amount of osteotomy of the medial condyle A3 and the lateral condyle A4 simply by loosening the fixture 63 and moving it in the width direction.

  The osteotomy scales 601 and 602 for the medial condyle A3 and the lateral condyle A4 of the osteotomy pretreatment jig 1 according to the sixth embodiment of the present invention will be described with reference to FIG. These osteotomy scales 601 and 602 are attached to guide grooves 171 and 172 provided on the front side in parallel with the upper surface 11 of the gap block 10 as shown in FIG. The guide grooves 171 and 172 are examples of slots provided in parallel to the upper surface 11 and have a so-called T-slot shape. The osteotomy scales 601 and 602 include a scale block 62, an anchor piece 67, and a fixture 63. The scale block 62 is marked with a scale 621 based on the upper surface 11 of the gap block 10 in units of 1 mm. Specifically, the scale 621 is composed of ruled lines and dots that mark every 5 mm. Similar to the scale block 62 of the fifth embodiment, the scale 621 is provided so as to reach the side surface of the scale block 62. The base 625 of the scale block 62 has a through hole 627 that is larger than the opening width of the guide grooves 171 and 172 and through which the fixture 63 is inserted. Further, the scale block 62 is formed to be thin enough that the reference need not be re-adjusted even if the gap block 10 has a different inclination angle of the upper surface 11. The anchor piece 67 is disposed in the guide grooves 171 and 172 and is fitted to the screw of the fixture 63. One of the anchor piece 67 and the fixture 63 may be a male screw and the other a female screw. Therefore, a stud bolt may be attached to the anchor piece 67, a screw hole may be provided in the fixture 63, and they may be fastened together. In addition, the osteotomy scales 601 and 602 are similar in structure to the medial condyle A3 and the external condyle A4 as in the osteotomy scales 601 and 602 of the fifth embodiment, and the same shape can be used.

  The osteotomy scales 601 and 602 of the osteotomy pretreatment jig 1 configured as described above can fix the scale block 62 at any position in the guide grooves 171 and 172. Further, by loosening the fixture 63, the scale block 62 can be freely moved along the guide grooves 171 and 172, and the angle can be easily adjusted around the screw of the fixture 63. Therefore, the osteotomy scales 601 and 602 can be easily attached to or detached from the gap block 10. Further, even if the inclination angle of the upper surface 11 of the gap block 10 changes, the operability does not change.

  In the osteotomy pretreatment jig 1 shown in each of the above-described embodiments, the configuration having the same function can be used by replacing the corresponding configuration in the other embodiments. Further, the shape of each component is not limited to the shape illustrated in each embodiment as long as the same function is achieved.

  For example, the fixtures of the osteotomy scales 601 and 602 in the first, third, and fourth embodiments may be attached from the side surface instead of the front side of the scale block 62. In the fifth embodiment, the arm portion 75 of the mark 70 is a round bar or a square bar, and the osteotomy scales 601 and 602 have through-holes that match the cross-sectional shape of the arm portion 75 in the base portion 625 of the scale block 62. It may be possible to fix it at any position with a fixing tool.

  Further, when the mark 70 is attached to the mark mounting portion 34 of the movable main body 30, it may be fixed with a screw so as to be firmly held, or the structure of the O-ring groove of the moving screw 64 of the fourth embodiment is adopted. You may do it. Furthermore, the scale block 62 of the osteotomy scales 601 and 602 of the first embodiment may be finely adjusted by adopting the same mechanism as the moving screw 64 with respect to the guide 612 of the stem 61.

  The gap block 10 only needs to be able to relatively position the femur A and the tibia B so that the femur A in the bent position is internally rotated with respect to the proximal tibia Ba. Therefore, the gap block 10 is not limited to the shape in which the upper surface 11 is inclined as shown in each embodiment, but the portion that supports the lateral posterior condyle A43 is located on the proximal tibia Ba rather than the portion that supports the medial condyle posterior A33. Anything higher than that is acceptable. That is, the upper surface 11 of the gap block 10 is not limited to a flat inclined surface, and may have a step. In addition, in order to change the angle at which the femur A is internally rotated, the inclination angle 11a of the upper surface 11 is not replaced for each gap block, but two blocks that separately support the medial condyle posterior A33 and the lateral condyle posterior A43 are provided. The gap block 10 may be configured by being connected.

  DESCRIPTION OF SYMBOLS 1 ... Bone cutting pretreatment jig | tool, 10 ... Gap block, 11 ... Upper surface, 12 ... Lower surface, 141, 142 ... Slot, 151, 152 ... Slot, 171, 172 ... Guide groove (slot), 20 ... Base plate, 30 ... Movable body, 33 ... guide hole, 34 ... mark attachment, 40 ... caliper, 44 ... mark, 50 ... gap scale, 52 ... scale, 601,602 ... bone cutting scale, 61 ... stem, 62 ... scale block, 621 ... Scale, 63 ... Fixing tool, 64 ... Moving screw, 70 ... Mark, 71 ... Osteotomy line, 72 ... Central window, 73 ... Inner window, 74 ... Outer window, A ... Femur, Aa ... Distal surface of femur, Ab ... anterior osteotomy surface, Ab1 ... proximal end, Ac ... posterior osteotomy surface, A2 ... distal femur, A3 ... medial condyle, A32 ... medial attachment, A33 ... medial condyle posterior, A4 ... lateral condyle, A4 ... lateral attachment part, A43 ... posterior lateral condyle, A5 ... patella surface, Ba ... proximal tibia, L1 ... medial collateral ligament, L2 ... lateral collateral ligament, Lx ... transcondylar axis (transepicondyla axis), K Knee joint, T artificial knee joint, T1 femoral component, Ta peghole.

Claims (13)

An osteotomy pretreatment jig used before performing osteotomy for forming an anterior osteotomy surface and a posterior osteotomy surface in order to replace the knee joint with an artificial knee joint,
Placed on the proximal surface of the tibia, cut perpendicular to the functional axis of the tibia, abutting the posterior medial and lateral condyles of the flexed femur, and the posterior medial condyle of the flexed femur And a gap block for holding a posterior condylar axis passing through the lateral posterior condyle in a state of being internally rotated with respect to the proximal surface of the tibia. The gap block has the posterior condylar axis relative to the proximal surface of the tibia to such an extent that the transcondylar axis passing through the attachment portion of the medial collateral ligament and the lateral collateral ligament to the femur is parallel to the proximal surface of the tibia. The osteotomy pretreatment jig according to claim 1, wherein the jig is held in an internally rotated state. Positioned with respect to the proximal end of the anterior osteotomy surface of the distal femur determined in accordance with the size of the artificial knee joint prepared in different sizes in a plurality of stages, and the artificial knee joint in the distal femur A movable body provided with a guide hole indicating a position to pierce a peg hole for installing the femoral component of
A mark for displaying a posterior osteotomy surface of the distal femur mounted on a mark attachment portion provided on the movable body corresponding to the size of the artificial knee joint selected when positioning the movable body;
A gap scale having a scale indicating the distance from the proximal surface of the tibia to the posterior osteotomy surface distal to the femur;
The osteotomy scale further comprising a scale for displaying a distance to each of the posterior medial condyle and the posterior lateral condyle in a direction perpendicular to the posterior osteotomy surface indicated by the mark. The osteotomy pretreatment jig described in 1. A base plate attached to the distal femur formed on the medial and lateral condyles of the femur perpendicular to the functional axis of the femur in a flexed position placed on the gap block;
A caliper that is fixed to the movable body and points to a proximal end of an anterior osteotomy surface formed when the anterior portion of the distal femur is osteotomized;
The movable body slide fits to the base plate parallel to the distal femur surface;
The osteotomy scale displays an osteotomy scale for a medial condyle having a scale that displays a distance from the posterior osteotomy surface to the posterior medial condyle, and a distance from the posterior osteotomy surface to the lateral posterior condyle. An osteotomy scale for the lateral condyles having a scale,
The mark displays the distance from the proximal surface of the tibia to the posterior osteotomy surface on the gap scale, displays the posterior osteotomy amount of the medial condyle on the osteotomy scale for the medial condyle, The osteotomy pretreatment jig according to claim 3, wherein the amount of posterior osteotomy of the lateral condyle is displayed on the osteotomy scale for the lateral condyle. The gap block has a transcondylar axis passing through a portion where the medial collateral ligament adheres to the medial epicondyle distal to the femur and a portion where the lateral collateral ligament adheres to the lateral epicondyle. The osteotomy pretreatment jig according to claim 4, further comprising an upper surface that is inclined with respect to the proximal surface of the tibia by an angle corresponding to an angle of rotation with respect to the functional axis. The osteotomy pretreatment according to claim 3, wherein the movable body has a mark attachment portion for attaching the mark in one-to-one correspondence with the size of the artificial knee joint. jig. 5. The osteotomy pretreatment jig according to claim 4, wherein the caliper has a mark for positioning on the movable main body in a one-to-one correspondence with the size of the artificial knee joint. . The caliper is
An outer caliper that is fixed to the upper end of the movable body on the outer condyle side, wraps around the outer condyle, and contacts the proximal end of the anterior osteotomy surface;
An inner caliper that is fixed to the upper end of the movable body on the inner condyle side, wraps around the inner condyle, and contacts the proximal end of the anterior osteotomy surface;
For a center that is fixed to a central upper end of the movable body that faces a portion between the lateral condyle and the medial condyle and that abuts the proximal end of the anterior osteotomy surface beyond the patella surface of the femur from the front. The osteotomy pretreatment jig according to claim 4, wherein one of the calipers is selected and attached. The osteotomy scale for the medial condyle and the osteotomy scale for the lateral condyle are:
A stem that moves parallel to the lower surface of the gap block;
A scale block mounted on the stem that is provided with the scale and is movable perpendicularly to the lower surface of the gap block;
The osteotomy pretreatment jig according to claim 4, further comprising a fixture that fixes the scale block to the stem. The stem is attached to a slot provided in the gap block parallel to the lower surface of the gap block,
The osteotomy pretreatment according to claim 9, wherein the osteotomy scale for the medial condyle and the osteotomy scale for the lateral condyle further include a moving screw that moves the stem along the slot. jig. The gap block has a slot provided in parallel to the upper surface,
The medial condyle osteotomy scale and the lateral condyle osteotomy scale are mounted on the slot and moved along the slot, and the scale is provided on a surface perpendicular to the upper surface and the lower surface. A scale block mounted on the stem so as to be rotatable along the stem, a fixture for fixing the scale block to the stem, and a moving screw for moving the stem along the slot. The osteotomy pretreatment jig according to claim 5. The osteotomy scale for the medial condyle and the osteotomy scale for the lateral condyle are:
The osteotomy pretreatment jig according to claim 4, wherein the osteotomy pretreatment jig is attached to the mark so as to be movable along an osteotomy line indicating the posterior osteotomy surface marked on the mark. The mark is
A central window showing the gap scale scale from the front,
A medial window showing the scale of the osteotomy scale for the medial condyle from the front;
The osteotomy pretreatment jig according to claim 4, further comprising an outer window that allows a scale of the osteotomy scale for the outer condyles to be seen from the front.

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