JP2011172920A - Instrument for orthopedics surgery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a highly versatile orthopedic surgery instrument by which low invasive operation can be accurately carried out, total cost is suppressed inexpensive, and operation time can be shortened. <P>SOLUTION: The instrument for orthopedic surgery includes: an articulation model 1 which has a shape of a bone articulation part of a patient made by rapid prototyping using three-dimensional image data of a bone articulation part acquired from a patient and a three-dimensional alignment shaft hole part 2 formed for inserting an intramedullary alignment rod set by a preoperative program; and a setting guide machine 10 which is coupled to the articulation model 1 and equipped with adjusting parts 12-17 which are adjustable of spaces to a plurality of feature position parts of the articulation model 1, a first mounting part 10a, 20 for mounting the intramedullary alignment rod, a second mounting part 19 for mounting the intramedullary alignment rod, and a third mounting part 18 for mounting bone removal equipment. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an orthopedic surgical instrument based on a three-dimensional preoperative plan.

  In orthopedic surgery, fractures and / or deformed bones are reconstructed and fixed to the alignment of the surgical plan using an implantable fixation material (implant). Artificial joints can also be used to treat patients with joint cartilage and bone aging deformation, congenital bone morphological abnormalities, osteoarthritis caused by fracture healing, or rheumatoid arthritis. is there. The conventional orthopedic surgery using these implants will be described taking knee joint prosthesis replacement as an example.

  FIG. 13 is a schematic diagram showing functional axes (alignment) of the femur and tibia of the knee prosthesis. FIG. 13A shows the functional axes and knee joint positions of the right foot femur FM and tibia TB. FIG. 13B shows a positional relationship and a functional axis mainly in the knee joint in the bent state.

  FIG. 14 is a schematic side view showing a femur FM and a tibia TB in which bones of joint portions have been excised in order to install an artificial knee joint. 14A shows the cutting positions C11 to C15 on the femur FM side, and FIG. 14B shows the femoral component a after installation. FIG. 14C shows the cutting position C21 on the tibial TB side, and FIG. 14D shows the tibial component b and the polyethylene insert c after installation.

  As shown in the drawing, the knee prosthesis is composed of a femoral component a, a tibial component b, and a polyethylene insert c of the joint portion. Since each size varies depending on the patient, usually several different-sized artificial knee joints are prepared in advance.

  In the operation of the knee prosthesis, a deformed cartilage and bone are accurately bone-removed perpendicularly to the functional axis, and an installation surface for fixing the prosthetic joint component is provided.

On the tibial TB side, in order to fix the tibial component b to the tibia, bone is excised from the articular surface to create a flat surface perpendicular to the tibial function axis.
Similarly, on the femur FM side, cartilage and bone deformed from the distal part of the femur FM are excised, and five installation surfaces C11 to C15 are provided for fixing the femoral component a to the femur. The five installation surfaces C11 to C15 are respectively a surface C11 perpendicular to the functional axis of the femur FM, two front and rear surfaces C12, C13 parallel to the functional axis, and two surfaces C14, C15 of inclined installation surfaces of the chamfered portion. is there.

  As described in Non-Patent Document 1, in order to improve the long-term durability of the knee prosthesis, it is important that these bone resections are accurately performed with respect to the functional axis, and Choosing a knee prosthesis size that fits the patient is important.

  As described in Non-Patent Document 2, in the conventional artificial knee joint surgical instrument method, in order to determine the direction of the bone resection surface, an intramedullary rod is inserted into the bone marrow cavity, and the direction is used as a reference. Osteotomy is performed with the angle of bone resection adjusted. However, in this method, it is pointed out that the intramedullary rod of the surgical instrument does not always enter the intended direction in the bone marrow cavity, and the probability that the component is installed at the correct alignment position is low. Furthermore, complications such as invasion of the bone marrow cavity by the intramedullary rod, thrombosis due to bleeding from the intramedullary cord and fat embolism have been reported.

  As this improvement measure, the technique shown in Patent Document 1 which is a method of reflecting the three-dimensional preoperative plan in actual surgery is considered. This method is a technique using a surgical instrument using a special intramedullary rod that can measure the relationship between the direction of the intramedullary rod and the bone resection position in a three-dimensional preoperative plan and reflect the value. However, this method also does not solve the problem of complications such as bleeding and thrombosis caused by invading the bone marrow cavity with an intramedullary rod.

  On the other hand, as a method for accurately guiding the preoperative plan during the operation, there is a method using a navigation device as described in Non-Patent Document 3. In this method, the navigation device is very expensive, and it is necessary to drive an antenna pin equipped with an infrared sensor or the like to make the computer recognize the position of the bone. In addition, there are many problems such as that the operation time is extended due to the necessity of registration work for the computer to recognize the bone position. For this reason, the penetration rate of navigation devices is very low at present.

  There is a need for a surgical instrument that is a system having a function of accurately reflecting a three-dimensional preoperative plan in an operation, and that can replace a navigation device and that can be operated at a low cost and can shorten an operation time.

  Furthermore, as a recent new method, as described in Non-Patent Documents 4 and 5, using a rapid prototyping technique, a custom-made surgical instrument adapted to the bone shape of an individual patient is created. Attempts have been made to perform bone resection with a custom-made instrument in close contact with the bone at the joint.

  The accuracy of bone resection is highly dependent on the accuracy of the instrument's adhesion to the bone. And since it is a custom-made instrument pre-operatively prepared, the dimensions of the main part of the instrument cannot be adjusted and changed by a simulation operation immediately before the operation. Similarly, there is no function to adjust the direction of the instrument according to the functional axis even during the operation, so that the compatibility with the bone may be deteriorated depending on the manufacturing crossing of the made-to-order instrument and the quality of the design. It is expected that accuracy will also be affected.

JP 2009-082444 A

All of knee prosthesis [TKA]-For safe and reliable surgery-Publisher: Medical View Co., Ltd., pages 74-81, basic techniques, acquisition of normal alignment, Takaaki Shishido All of artificial knee joint [TKA]-For safe and reliable surgery-Publisher: Medical View Co., Ltd., pages 82-91, Surgical instruments effective for bone cutting, Hiroyuki Nozaki All of artificial knee joint [TKA]-For safe and reliable surgery-Publisher: Medical View Co., Ltd., pages 176-183, Navigation Surgery, Takuji Nakamura CLINICAL ORTHOPEDICS AND RELATED RESEARCH, Number 354, p. 28-38, Surgical With Image Individual Templates, Klaus Radermacher, Dipl-Ing et. al. Computer-aided orthopedic surgery using individual templates created based on images 50 RTHOPEDICS, September 2008 Volume 31, Number 9 p. 927-930, Patient-specific approach in total knee arthroplasty, Adolph V. et al. Lombardi Jr. Patient-specific approach in total knee arthroplasty

As described above, there is a need for a surgical instrument that accurately reflects the three-dimensional preoperative plan in the surgery. However, any of the conventional surgical instruments may invade the bone marrow or the like.
Further, in the method using the latest navigation technology, the operation time is extended, and the surgical instrument is large and expensive, so that it cannot be popularized, and the possibility of invasion by the antenna pin cannot be excluded.

  The present invention has been made in view of the above circumstances, and the purpose of the present invention is to perform the operation accurately with a relatively low invasiveness, keep the total cost low, and reduce the operation time. Another object of the present invention is to provide a highly versatile orthopedic surgical instrument.

  One aspect of the present invention is to insert a surgical instrument having the shape of the bone of the patient, which is prepared by rapid prototyping using data of a three-dimensional shape image of the bone obtained from the patient, and set in the preoperative plan. A bone model in which a three-dimensional alignment shaft hole is formed, and an adjustment unit which is combined with the bone model and can adjust the distance between a plurality of feature positions of the bone model, and guides intramedullary alignment of a surgical plan An installation guide instrument provided with a first mounting portion for mounting a rod, a second mounting portion for mounting an extramedullary alignment rod, and a third mounting portion for mounting a guide of an osteotomy device or a bone drilling device. It is characterized by having.

  According to the present invention, the treatment can be performed accurately with a relatively low invasiveness, the total cost can be kept low, and the operation time can be shortened.

The perspective view which shows the femur full size model which concerns on one Embodiment of this invention. The perspective view which shows the femoral intercondylar model which concerns on the same embodiment. The perspective view which shows the combination relationship of the femoral installation guide instrument based on the embodiment, a femoral intercondylar part model, and a femur model. The perspective view which shows the state which assembled | attached the femur installation guide instrument which concerns on the embodiment, the femoral intercondylar part model, and the femur model. The perspective view which shows the tibial full size model which concerns on the same embodiment. The perspective view which shows the tibia medial epicondyle model which concerns on the same embodiment. The perspective view which shows the combination relationship of the tibial installation guide instrument based on the embodiment, a tibial medial epicondyle model, and a tibial model. The perspective view which shows the state which assembled | attached the tibial installation guide instrument based on the embodiment, the tibial medial epicondyle model, and the tibial model. The perspective view which shows the result of having adjusted the position and angle of the installation guide apparatus with respect to a bone model without the femoral intercondylar part model which concerns on the embodiment. The perspective view which shows the femoral intercondylar part model which used the thermoplastic resin as an intermediate model which concerns on the embodiment. The figure which shows the external appearance structure and mounting state of the position recognition marker which concern on the embodiment. The figure which shows the use condition of the femoral installation guide instrument equipped with the position recognition marker which concerns on the embodiment. The figure which shows the outline of the functional axis (alignment) of the femur and tibia of an artificial knee joint. The figure which shows the femur and tibia which are bone-removed in order to install an artificial knee joint, and the installed artificial knee joint.

Hereinafter, an embodiment in which the present invention is applied to an artificial knee joint replacement surgery instrument for a knee joint will be described with reference to the drawings.
[Three-dimensional preoperative planning and manufacturing of full-scale bone crops]
First, the entire length of each lower limb of a patient is photographed with a CT apparatus or an MRI apparatus, a three-dimensional bone model is created on the computer from this image data, and a three-dimensional preoperative plan in artificial knee joint replacement is performed. The work up to this point is the same as the preoperative planning of the existing three-dimensional templating system and navigation system for artificial knee joints.

  Next, alignment (function) that enables determination of a three-dimensional installation position on the bone models 1 and 3 and the structures 5 and 8 that fill the gap between the surgical instruments 10 and 21 by using the three-dimensional data based on the preoperative plan. After designing the shaft holes, etc., each is manufactured using rapid prototyping technology.

[Equipment configuration on the femur]
FIG. 1 shows a full-size femur model 1 manufactured using the rapid prototyping technique described above. As shown in the figure, the femoral model 1 has a fixed pin at a position where the three-dimensional alignment shaft hole 2 of the femur designed in the preoperative plan and a 3.2 mm diameter fixing pin of the surgical instrument are installed. The holes 2a to 2d are respectively made.

  In order to combine with the femur model 1, a femoral intercondylar model 5 as an intermediate model shown in FIG. 2 is also produced by a rapid prototyping technique. The inter-femoral intercondylar model 5 is constructed so as to conform to the shape of the inter-condylar portion of the femoral model 1, and is particularly important as a Merckmar for installing an artificial knee joint. The intercondylar reference surface 7 is brought into contact with the femur model 1 so that the mutual shapes are exactly matched.

  In addition, the interfemoral intercondylar model 5 is formed with a three-dimensional alignment shaft hole 5a that matches the three-dimensional alignment shaft hole 2 of the femur model 1 in the axial direction. These two feature models 1 and 5 are used in combination.

  As shown in FIG. 3, a femoral placement guide instrument 10 is used for the above-described feature models 1 and 5. The femoral placement guide instrument 10 has a slide hole portion 10a into which the alignment rod 11 is inserted, and the alignment rod 11 passes through the three-dimensional alignment shaft hole 5a of the interfemoral intercondylar model 5 from the slide hole portion 10a. It is inserted into the three-dimensional alignment shaft hole 2 of the femur model 1 and used in combination.

  The slide hole portion 10a can be slid in the vertical direction in the figure in a state where the femoral installation guide fixing screw 20 is loosened, and the angle at which the alignment rod 11 is held by the internal joint mechanism is also three-dimensional. Can be varied.

  Further, in the femoral placement guide instrument 10, the front surface of the femur is adjusted by adjusting the screws 12 and 13 provided for selecting the distal femur distal end resection guide 18 projecting perpendicularly to the longitudinal direction of the femoral placement guide instrument 10. By adjusting the screws 14, 15, 16, and 17, the contact distance with the femoral condyle can be variably set.

  Each of the screws 12, 13, 16, and 17 has a hollow structure, and a fixing pin (not shown) having a diameter of 3.2 mm, which will be described later, is passed through the fixing pin holes 2a to 2d of the femur model. The femoral placement guide instrument 10 can be fixed to the femur at a position reflecting the three-dimensional surgical plan from the contact position of the screw.

  Further, a rod mounting hole 19 for mounting an extramedullary alignment rod (not shown) at the time of surgery is provided in the upper part of the main body of the femoral placement guide instrument 10.

[Assembly and adjustment of each instrument on the femur side]
FIG. 4 shows a state in which the femoral placement guide instrument 10 is assembled to the femoral intercondylar model 5 and the femoral model 1. A three-dimensional alignment formed on the femoral model 1 by inserting the alignment rod 11 from the front surface of the femoral placement guide instrument 10 so as to pass the slide hole 10a and interposing the inter-femoral condyle model 5 through the three-dimensional alignment shaft hole 5a. Pass through the shaft hole 2.

  Thus, the femoral placement guide instrument 10 provided in the femoral placement guide device 10 is fixed as a state in which the femoral placement guide device 10, the femoral intercondylar part model 5, and the femoral model 1 are closely combined with the alignment lot 11 as an axis. The position and angle of the alignment rod 11 are fixed by tightening the screw 20.

  Then, after the slit portion of the femoral distal end resection guide 18 is slid to a level that references the intercondylar bone of the femoral model 1 to adjust and fix the bone resection position, the screws 12 and 13 are attached to the front surface of the femur. Screw in until it touches. Further, the screws 14, 15, 16, and 17 are screwed into the femur model 1 until the screw tips come into contact with each other, and the lengths are adjusted.

[Simulation before operation on the femur]
The position of each adjustment screw 20, 12, 13, 14 to 17 in the full-scale femoral model 1 before the operation is located, the value of the preoperative plan and the installation of the instrument on the femoral model 1 By measuring the length of each adjustment site to determine whether the position values are the same, the installation state of the instrument in accurate alignment is grasped and the operation is started.

[Operation during femoral surgery]
At the time of surgery, the full-size femur model 1 is not used, but the femoral intercondylar model 5 and the femoral placement guide instrument 10 are used in combination. The femoral placement guide instrument 10 and the interfemoral intercondylar model 5 are brought into close contact with the patient's femoral joint so as to obtain the best-fit position that reflects the preoperative simulation.

  Then, without inserting an intramedullary rod into the bone marrow cavity, an extramedullary rod (not shown) is mounted in the rod mounting hole 19 on the upper part of the femoral installation guide instrument 10 to confirm the alignment and to confirm the compatibility of the femoral installation guide instrument 10. Check. By performing an operation to finely adjust each adjustment screw as necessary, a bone resection guide instrument for setting an artificial joint can be placed at the position of the plan before the three-dimensional operation without invading the bone side with an intramedullary rod or the like. Induce.

  As for the details of the three-dimensional position adjustment method on the femur side, the angle is finely adjusted by the femoral bending adjustment screws 14 and 15 in the bending / extension direction. Further, regarding the varus / valgus direction, after finely adjusting the angle with the femoral varus / valgus adjusting screws 16 and 17, two fixing pins (not shown) having a diameter of 3.2 mm are driven into the connector through the hollow holes, and the femoral placement guide instrument 10. To fix. A hole formed by this pin becomes a peg fixing hole described later.

  Further, in the adjustment of the rotation direction, the slit portion of the femoral distal end resection guide 18 is fixed by sliding it to a level that references the bone at the intercondylar portion of the femur, and then the angle is adjusted by the rotation angle adjusting screws 12 and 13. Make fine adjustments.

  The distal end femoral resection guide 18 is fixed to the front surface of the femur by driving two 3.2 mm diameter fixing pins into the rotation angle adjusting screws 12 and 13 having a hollow structure.

  Through these series of operations, the position of the fixing pin for the femoral resection instrument is guided to the resection position of the three-dimensional preoperative plan and reproduced.

  All the instruments including the femoral placement guide instrument 10 and the interfemoral intercondylar model 5 are once removed with only the 3.2 mm-diameter fixing pins remaining on the front surface of the femur. A resection guide (not shown) for a different end of the femur is attached to a 3.2 mm diameter fixing pin remaining on the front surface of the femur, and the distal end of the femur is excised as shown by a cut surface C11 in FIG.

  Subsequently, the two fixing pins left at the distal end of the femur are removed, and a peg (not shown) is inserted into the hole of the pin mark remaining on the bone side and fixed, and the remaining four surfaces (cutting of FIG. 14A) are performed. Surfaces C12-C15) are excised and the artificial knee joint femoral component is placed.

[Effects of preoperative planning on the femoral side]
By adjusting the three-dimensional position of the instrument including the femoral placement guide instrument 10 by a series of operations before the operation, and by the surgical simulation using the full-scale femur model 1, the operator is in a deformed joint state. And the position and size of bone defects and osteophytes can be grasped three-dimensionally before the operation. During the operation, the femoral component of the knee prosthesis can be installed with a relatively minimally invasive and safe and accurate alignment within a short time, and the entire cost can be realized at a low cost.

[Tibial instrument configuration]
FIG. 5 shows a full-size tibial model 3 made using rapid prototyping technology. As shown in the figure, the tibial model 3 has a tibial three-dimensional alignment shaft hole 4 designed in the preoperative plan and fixing pin holes 4a and 4b for installing a fixing pin having a diameter of 3.2 mm. Yes.

  In order to combine with the tibial model 3, the tibial medial epicondyle model 8 as an intermediate model shown in FIG. 6 is also produced by rapid prototyping technology. The tibial medial epicondyle model 8 is constructed so as to conform to the shape of the front surface of the medial joint surface of the tibial model 3, and is an arm that conforms to the concave surface of the medial part of the intercondylar bulge, which is particularly important as a Merckmar for artificial knee joint placement. The portion 9 is abutted against the tibial model 3 and is imitated so that the mutual shapes are exactly matched.

  In addition, an intercondylar pin through hole 30 is formed in the medial epicondyle model 8 of the tibia. These two feature models 3 and 8 are used in combination.

  As shown in FIG. 7, a tibial placement guide instrument 21 is used for the above-described feature models 3 and 8. This tibial placement guide instrument 21 has a hole 21a for inserting the intramedullary alignment lot 11 in the upper part thereof before the operation, and the alignment rod 11 is inserted into the alignment hole 4 of the tibial model 3 from the hole 21a of the instrument 21. use.

  A tibial resection block 27 is attached to the tibial placement guide instrument 21 for use. The tibial resection block 27 is combined with the tibial medial epicondyle model 8. A slit 27a is formed in the tibial resection block 27, and the slit 27a is used at the time of bone resection.

  The tibial placement guide instrument 21 is provided with a fixing knob 21b for inserting and fixing a tibial intercondylar fixing pin 29 and adjusting screws 22 and 23. The tibial resection block 27 is provided with adjustment screws 24, 25 and 26 having a hollow structure. A mounting hole 28 for an extramedullary alignment rod is provided on the distal side from the tibia of the tibial placement guide instrument 21.

[Assembly and adjustment of each instrument on the tibial side]
FIG. 8 shows a state where the tibial placement guide instrument 21 is assembled together with the tibial medial epicondyle model 8 and the tibial model 3.
First, the three-dimensional bone of the tibia is brought into contact with the concave surface portion of the tibial model 3 at the side of the characteristic hilly portion so that the back surface of the upper arm portion 9 of the tibial medial epicondyle model 8 follows. Be able to guide the resection level.

  In this state, the alignment rod 11 fixed to the tibial installation guide 21 is inserted into the alignment hole 4 of the tibial model 3. The tibial resection block 27 temporarily attached to the tibial placement guide 21 is adjusted so that the tibial resection block 27 can be accurately combined with the tibial medial epicondyle model 8 and pressed against the front surface of the tibial model 3 so as to be in close contact with the full-size tibial model 3 Fix it.

  Then, the tibial intercondylar fixation pin 29 is inserted through the intercondylar pin through-hole 30 of the tibial medial epicondyle model 8, and further from the hollow type adjusting screws 24, 25 of the tibial resection block 27 to the holes 4a, 4b of the tibial model 3.通 し Pass the fixing pin with a diameter of 2 mm and press it against the tibial model 3 to tighten the fixing knob.

  The adjustment screws 22, 23 of the tibial placement guide 21 and the adjustment screws 25, 25, 26 of the tibial resection block 27 are turned so that the tibial medial epicondyle model 8 is in close contact with the tibial resection block 27 and further in close contact with the tibial model 3. By adjusting, the tibial resection level and posterior inclination necessary for the installation of the human knee joint are fixed at the resection level of the three-dimensional preoperative plan. Here, an unillustrated alignment rod (not shown) is inserted into the rod mounting hole 28, and the three-dimensional installation position is confirmed.

[Tibial pre-operative simulation]
The position of each adjustment screw 21b, 22, 23, 24 to 26 of the surgical instrument is located in the full-size tibial model 3 before the operation, the value of the preoperative plan, the tibial placement guide instrument 21, and the tibial medial epicondyle Whether the installation position of the model matches or the length of each adjustment part is measured, the installation state of the instrument in accurate alignment is grasped and the operation is started.

[Operation during tibial surgery]
In the intra-surgical operation on the tibia side, the intramedullary rod 11 is not inserted into the bone marrow cavity, and invasion to the bone is avoided. Instead, an alignment rod outside the medulla that can be attached to the tibial placement guide instrument 21 is inserted into the alignment rod attachment hole 28 of the tibial placement guide 21 and the operation is advanced while confirming the alignment.

  The tibial medial epicondyle model 8, which is a structure that fills the space between the tibial resection guide 27 and the tibia, is combined and pressed against the medial joint surface of the patient's tibia. At this time, the back surface of the arm 9 at the upper part of the medial epicondylar model 8 of the tibial bone follows the concave surface beside the characteristic hill portion inside the intercondylar ridge. The fixation of the tibial intercondylar fixation pin 29 is released, and the pin 29 is fixed according to the bone in front of the intercondylar ridge. Then, it is confirmed whether the functional axis of the patient matches the direction of the extra alignment rod (not shown).

Next, details of the three-dimensional position adjustment method of the tibial placement guide instrument 21 will be described.
The rotation direction is finely adjusted using tibial rotation adjusting screws 24 and 25 on the front surface of the tibial resection block 27.
Regarding the posterior inclination, the probe portions at the tips of the tibia posterior inclination adjusting screws 22 and 23 on the shaft portion of the tibial placement guide instrument 21 are pressed percutaneously or from the top of the skin against the tibia anterior surface and the tibia crest. Fine adjustment is performed using screws 22 and 23.

  The varus / valgus is finely adjusted using the varus / valgus angle adjusting screw 26 on the side surface of the tibial resection block 27. While confirming the extraneous rod (not shown) mounted in the alignment rod mounting hole 28, the position of the three-dimensional preoperative plan is appropriately corrected by finely adjusting these three-dimensional axes during the operation as necessary.

  Then, the tibial placement guide 21 is fixed by a 3.2 mm diameter fixing pin hole through the hollow type adjusting pins 24 and 25 on the front surface of the tibial resection block 27, and the bone is excised from the slit 27a of the tibial resection block 27 to obtain an artificial knee joint. Place the tibial component properly.

[Tibial preoperative planning and effects after surgery]
By adjusting the three-dimensional position of the instrument including the tibial placement guide instrument 21 by a series of operations before the operation, and by the surgical simulation using the full-size tibial model 3, the operator can determine the deformed joint state and bone. The position and size of the defect and osteophyte can be grasped three-dimensionally and can be operated. During the operation, the artificial knee joint tibial component can be installed with a relatively minimally invasive, safe and accurate alignment in a short time in accordance with the preoperative plan, and the overall cost can be realized at a low cost.

[Modification of intermediate model]
In the embodiment described above, the femoral intercondylar part model 5 for the femur model 1 and the tibial medial epicondyle model 8 for the tibial model 3 are each designed in the virtual space of the computer at the stage of preoperative planning, and used as intermediate models in advance. Although described as being prepared, some surgeons may reduce the incision range of the operative field for reasons such as reducing the physical burden on the patient. The tibia medial epicondyle model 8 may be too large to correctly contact the patient's bone.

  Therefore, after the surgeon arbitrarily adjusts the position of the installation guide instrument relative to the bone model, for example, a thermoplastic resin material such as an olefin elastomer or a styrene elastomer is used and heated to a plastic state, so that the surgical instrument and bone Using the cured intermediate model, the intermediate model is formed by filling and fixing the intermediate, and after forming, the intermediate model is cured by, for example, applying cold water to the thermoplastic resin to determine the shape. It can also be used during actual surgery.

  By using this method, the incision range of the surgical field is assumed at the operator's discretion, and the intermediate model is interposed so as to fill the space between the surgical instrument in an appropriate part of the bone model. The three-dimensional shape can be accurately traced. Using the cured thermoplastic resin as an intermediate model, a through hole of an intramedullary alignment rod may be further formed between the bone model 1 (3) and the installation guide device 10 (21).

  In this way, even if the surgical field is limited based on the judgment of the doctor performing the operation, the shape and part of the intermediate model to be matched with the bone affected part are molded while considering the presence of cartilage tissue etc. in the bone joint part. An intermediate model that matches the affected bone area of a patient can be directly produced using a plastic resin.

  FIG. 9 shows the result of adjusting the position and angle of the installation guide instrument 10 relative to the bone model 1 by the position adjustment operation in FIG. Here, at the time of the adjustment, cylindrical sleeves 31, 31,... 3 are respectively provided at positions corresponding to the rotation angle adjustment screws 12 and 13 and femoral varus adjustment screws 16 and 17 of the femoral placement guide instrument 10. Adjustment is performed through the pin holes 2a to 2d of the bone model 1 through the fixing pins having a diameter of 2 mm, and then the sleeves 31 and 31 for the femur model 1 are removed even after the femoral placement guide instrument 10 is removed. ,... Are temporarily fixed with fixing pins (not shown).

  In this way, an intermediate model is prepared in place of the femoral intercondylar model 5 with the adjustment position of the femoral placement guide instrument 10 left by the sleeves 31, 31,. At the time of production, a thermoplastic resin in a heated plastic state, such as an olefin-based elastomer, is molded so as to cover all the femur model 1 in the range including the sleeves 31, 31,. To cure. When the thermoplastic resin is cured, the temporary fixing with the fixing pins of the sleeves 31, 31,... Is released, and the interfemoral intercondylar model, which is an intermediate model, is completed.

  FIG. 10 shows a femoral intercondylar model 32 as an intermediate model produced as described above. Although it is slightly irregular because it is made by placing the clay-like thermoplastic resin in a plastic state on the femur model 1 with fingers, its inner surface exactly matches the femur model 1 and the sleeve 31 , 31,... Can also be accurately maintained.

  Therefore, even when the femoral placement guide instrument 10 is attached to the patient's femoral joint during actual surgery, the femoral placement is adjusted by the preoperative doctor by interposing the interfemoral intercondylar model 32. The installation position and direction of the guide instrument 10 can be reproduced very accurately.

[In-situ instrument location check and adjustment]
In addition to the above-described embodiment, it is also conceivable to use a position recognition marker as a guide instrument in order to increase the installation accuracy of the surgical instrument on the bone of the patient during surgery.

  FIG. 11A shows an external configuration of the position recognition marker 40 attached to the femoral placement guide instrument 10. This position recognition marker 40 is formed by projecting three position marks 42, 42,... Having the same spherical shape on the surface of a triangular flat plate-like marker body 41. These position marks 42, 42,... Are painted so as to have different colors, for example, and the positional relationship can be easily grasped by pattern matching processing and color recognition processing in a computer described later.

  In addition, a pair of positioning convex portions 43 and 43 matching the rod mounting hole 19 of the femoral placement guide instrument 10 are formed on the back side of the marker body 41 of the position recognition marker 40, and one end of the side of the marker body 41 is formed. The contact portion 44 with the flange-shaped femur placement guide instrument 10 is formed.

  FIG. 11B illustrates a state in which the position recognition marker 40 is attached to the femoral placement guide instrument 10 and is being used during knee joint replacement for the femur FM.

  FIG. 12 shows a three-dimensional measurement for confirming the installation position of the femoral placement guide instrument 10 equipped with the position recognition marker 40 as shown in FIG. 11B in the state of being placed on the patient's femur during the operation. The state which is image | photographing with the camera 51 is illustrated.

  The three-dimensional measurement camera 51 is a stereo type digital camera having two imaging optical systems on the left and right sides, and is mounted on a stand 52. Pixel signals obtained by the three-dimensional measurement camera 51 are sent to the computer 53 in real time. Here, it is assumed that the computer 53 includes, for example, a computer main body 53B, a display 53D, a keyboard 53K, and a mouse 53P as a pointing device, which are mounted on a console that can move in the operating room.

  In the above-described configuration, when the operator visually confirms the installation position of the femoral placement guide instrument 10 with respect to the affected part, the position recognition marker for the three-dimensional measurement camera 51 is placed in the alignment rod mounting hole 19 of the surgical instrument. 40 is worn, and the position recognition marker 40 and the bone affected part are photographed by the three-dimensional measurement camera 51 so that they are within the same imaging range. Using the 3D measurement function program previously installed in the computer 53, the 3D solid bone model used in the operation plan in the virtual space in the computer, and the image data during the operation, which is actually taken, are used. , The relative displacement between the bone affected area and the femoral placement guide instrument 10 is calculated based on the angle and the distance, and the calculation results are displayed as numerical values on the display 53D, for example.

  Of course, the three-dimensional shape data and the like of the femoral placement guide instrument 10 and the position recognition marker 40 attached to the femoral placement guide instrument 10 are included in the three-dimensional measurement function program in advance.

  The surgeon repeats the operation of finely adjusting the surgical instrument including the femoral placement guide instrument 10 with reference to the display content on the display 53D and photographing the state using the three-dimensional measurement camera 51 as necessary. As a result, the femoral placement guide instrument 10 can be accurately placed according to the preoperative plan.

  In the computer 53, not only the relative angle and distance of the affected bone part and the femoral placement guide instrument 10 are displayed on the display 53D but also other informing means such as an intermittent beep interval and the like. By changing the pitch and expressing the relative angle and distance of the bone affected area and the femoral placement guide instrument 10, the surgeon can continue adjusting without listening to the affected area while listening to the beep sound. It is possible to make it possible.

  In this way, a marker for position recognition is attached to the installation guide instrument, and the relative positional relationship with the bone affected part compared with the preoperative plan in the three-dimensional space is calculated with the three-dimensional measurement camera 51 as the imaging means. By calculating with the computer 53 as the means, it can be installed more accurately according to the preoperative plan.

  The position marks 42, 42,... In the position recognition marker 40 are arranged as indices indicating the position and angle in the three-dimensional space of the femoral placement guide instrument 10 to which the position recognition marker 40 is attached. The shape, color, etc. are not limited to this embodiment.

  In addition, although the said embodiment demonstrated the case where it applied to each artificial joint instrument of the femur side of a knee joint, and the tibia side, this invention does not specify the joint site | part which replaces an artificial joint.

  In addition, in orthopedic surgery for the purpose of fixing an implant, it is applicable to any surgery in which an alignment rod and a bone resection guide or a drill pin are installed at a bone position in a surgical plan.

  In addition, the method of directly molding the intermediate model filling the space between the bone and the surgical instrument to guide to the preoperative plan position using thermoplastic resin is limited to the surgical instrument and surgical method. It can be applied to almost all plastic surgery for bone.

  In addition, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention in the implementation stage. Further, the functions executed in the above-described embodiments may be combined as appropriate as possible. The above-described embodiment includes various stages, and various inventions can be extracted by an appropriate combination of a plurality of disclosed constituent elements. For example, even if some constituent requirements are deleted from all the constituent requirements shown in the embodiment, if the effect is obtained, a configuration from which the constituent requirements are deleted can be extracted as an invention.

1 ... Full-scale femur model,
2 ... 3D alignment shaft hole of femur,
3 ... Full-scale tibial model,
4 ... 3D alignment shaft hole of tibia,
5 ... Femoral intercondylar model,
6 ... Reference surface of the front of the femur 7 ... Reference surface between the femoral condyles,
8 ... Tibial medial epicondyle model,
9 ... arm part (in the tibial medial epicondyle model),
10 ... Femoral placement guide instrument,
11 ... Alignment rod,
12, 13 ... Femoral rotation angle adjusting screw,
14, 15 ... Femoral flexion adjustment screw,
16, 17 ... thighbone valgus adjustment screw,
18 ... Guide distal resection guide,
19: Extraneous alignment rod mounting hole for the femur,
20 ... Femoral placement guide fixing screw,
21 ... Tibial placement guide instrument,
22, 23 ... Tibial posterior tilt adjustment screw,
24, 25 ... tibial rotation adjustment screw,
26 ... Tibial valgus adjustment screw,
27 ... Tibial resection block,
28 ... tibia extraneous alignment rod mounting hole,
29 ... Tibial intercondylar fixation pin,
30: Intercondylar pin through hole,
31 ... Sleeve,
32 ... model of femoral condyles
40: Position recognition marker,
41 ... Marker body,
42 ... Position mark,
43 ... positioning convex part,
44 ... abutting part,
51 ... 3D measuring camera,
52 ... Stand,
53. Computer.

Claims (7)

A three-dimensional alignment shaft hole for inserting a surgical instrument having the shape of the above-mentioned patient's bone and set in the preoperative plan, created by rapid prototyping using the data of the three-dimensional shape image of the bone obtained from the patient The bone model that formed the part,
An adjustment unit that can be combined with the bone model and can adjust an interval between a plurality of feature positions of the bone model, a first attachment unit for attaching a rod for guiding intramedullary alignment of an operation plan, and an extramedullary alignment rod An orthopedic surgical instrument comprising: a second mounting portion to be mounted; and an installation guide instrument provided with a third mounting portion for mounting a guide of a bone resection device or a bone drilling device.   An abutting portion produced by rapid prototyping using data of a three-dimensional shape image of a bone obtained from a patient, which is interposed between the bone model and the installation guide instrument, and matches the shape of the bone model The orthopedic surgical instrument according to claim 1, further comprising an intermediate model in which a through-hole penetrating the rod, drill or pin is formed. The orthopedic surgical instrument is for a femoral knee joint,
3. The orthopedic surgical instrument according to claim 2, wherein the abutting portion of the intermediate model abuts on an anterior flat surface portion and an intercondylar portion of a femoral knee joint. The orthopedic surgical instrument is for the tibial knee joint,
3. The orthopedic surgical instrument according to claim 2, wherein the abutting portion of the intermediate model abuts on a hill-shaped portion inside the intercondylar bulge of the tibial knee joint. The orthopedic surgical instrument is for the tibial knee joint,
The orthopedic surgical instrument according to claim 1, wherein the second mounting portion of the installation guide instrument has an adjustment screw that can be adjusted so that the extramedullary alignment rod is positioned on the tibial rough surface and the tibial crest. .   Further comprising an intermediate model made of a thermoplastic resin, which is combined between the bone model and the installation guide instrument and mounted with a guide member for the adjustment unit of the installation guide instrument in a plastic state. The orthopedic surgical instrument according to claim 1.   The orthopedic surgical instrument according to claim 1, further comprising a position recognition marker instrument on which at least three index members are arranged, which is attached to the installation guide instrument.

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