JP2018086200A - Artificial knee joint replacement surgical instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an artificial knee joint replacement surgical instrument in which a resection position and a resection angle of a tibia proximal end articular surface can properly be set by simple adjustment in artificial knee joint uni-condyle replacement surgery.SOLUTION: An artificial knee joint replacement surgical instrument (10) of the present invention includes a cut guide unit (7A) for guiding a cutting blade to resect a knee joint surface, an arm unit (4A) for supporting the cut guide unit in the vicinity of the tibial tuberosity, and a cut guide positioning rod (1A) for use in fastening fixation of the cut guide unit to the tibial tuberosity. A base (3A) of the arm unit comprises resection angle adjustment means for adjusting a backward inclination angle being an angle of inclination in the back-edge direction from the tibial anterior border to the level of the cut guide unit arranged at the tip of the arm unit.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an artificial knee joint replacement surgical instrument used when excising the joint surface at the femoral side proximal end of the tibia in artificial knee joint replacement.

  Total knee replacement (Total Knee Arthroplasty, TKA) as a total knee replacement (total condyles) as a total knee replacement (total knee arthroplasty, TKA) There has been known an artificial knee arthroplasty (UKA) in which one of the inner condyle side and the outer condyle side of a knee joint is partially excised and replaced with an artificial knee joint (Unicompartmental Knee Arthroplasty, UKA).

  In the total knee arthroplasty (TKA), a surgical instrument used for bone resection (so-called osteotomy or osteotomy) of the proximal end of the tibia on the femur side is a tibia of a positioning guide rod. Depending on the method of locking to, it can be roughly classified into an extramedullary type and an intramedullary type.

  For example, a conventional TKA tibial articular surface resection instrument of the extramedullary type has a cut guide portion (tibial slit 7A) having a horizontal slit 7d for inserting and guiding a cutting blade as shown in FIG. When the main fixing (fastening fixing) is performed at an appropriate position on the rough surface, as a preliminary work, the arm 14A of the proximal fixing member 13A attached to the cut guide positioning rod (main rod 1A) is temporarily provided in advance. After the locked (temporarily fixed) cut guide portion (tibial slit 7A) is aligned and positioned, it is firmly fixed (mainly fixed) to the rough surface of the tibia using pins, screws, etc. (See Patent Document 1).

  That is, in this example, the main rod 1A supported by the ankle clamp 8 that grips the periphery of the ankle and the upper end locked by the spike 5A driven into the joint surface of the upper end of the tibia is used for positioning the tibial slit 7A. Used as a rod. And, with respect to the upper end of the main rod 1A whose position is fixed, by shifting the connection point between the lower end and the ankle clamp 8 in two horizontal directions, the inclination in the front-rear direction with respect to the tibia (the front edge-the dorsal edge direction, The femoral head in which the pitch in the X-axis direction shown in the drawing and the inclination in the inner and outer directions with respect to the tibia (the median side of the body—the roll in the Y-axis direction shown in the drawing) is called the “functional axis” (or tibial bone axis). The main fixation (fastening fixation) of the tibial slit 7A to the rough surface of the tibia is performed in a state adjusted (aligned) so as to match a line (Z axis in the drawing) passing from the center to the knee joint center.

  In this state, the formation / guide direction of the slit 7d of the tibial slit 7A is referred to as “horizontal” in the treatment, and a plane (XY plane) orthogonal to the Z axis in the drawing is referred to as a “horizontal plane” in the treatment. This horizontal plane will later become a bone resection surface (osseous surface) by a cutting blade. Further, the slit for guiding the cutting edge (horizontal slit 7d) is tilted forward and backward in the X-axis front-rear direction (around the Y-axis) by pitch (pitck), and the left-tilt right-inclination in the Y-axis left-right direction (around the X axis) is rolled (roll). ), A plan view rotation (turning) around the Z axis is referred to as yaw.

  Further, for example, in the case of a conventional TKA tibial articular surface resection instrument of the intramedullary type, as shown in FIG. 13, a T-rod 1C (hidden line not along the functional axis) driven into the bone marrow cavity of the tibia A cut guide portion (T-) having a horizontal slit 7d for cutting blade insertion / guide is formed by an arm portion 14C projecting in a substantially horizontal direction from a T-rod guide 13C fitted to a shaft member called a temporary reference shaft. This is a reference for alignment adjustment of the cut guide 7C) (see Patent Document 2).

  As in the extramedullary type, the T-cut guide 7C supported (supported) at the tip of the shaft 6C slidably fitted in the arm portion 14C is tilted in the anteroposterior direction relative to the tibia (in the X-axis direction). To the rough tibial surface of the T-cut guide 7C in a state where the pitch angle) and the inward / outward inclination (roll angle in the Y-axis direction) are adjusted to match the functional axis or the tibial bone axis (Z-axis in the drawing). Is fixed (fastened).

  On the other hand, the cut guide portion (cutting head 7B) of a conventional UKA tibial articular surface resection instrument used for the artificial knee joint single condyle replacement (UKA) is an extramedullary type for TKA as shown in FIG. Alignment is adjusted using a sub-rod 6B (lateral bar) protruding in the horizontal direction (X-axis direction) from the main rod 1B similar to that used in the cutting tool (FIG. 12) as a temporary reference axis (patent) Reference 3).

  The main rod 1B has an inclination in the front-rear direction with respect to the tibia (pitch angle in the X-axis direction) and an inclination in the inner and outer directions (roll angle in the Y-axis direction) as a functional axis or a tibial bone axis (Z-axis in the drawing). The main fixing (fastening fixation) to the rough tibial surface of the cutting head 7B is performed in a state adjusted to match.

  In these conventional examples, after the fastening and fixing (main fixing) of each cut guide portion (the tibial slit 7A, the T-cut guide 7C, and the cutting head 7B), the bone cutting of the tibial joint surface by the cutting blade is started. Before, a member that is located in front of each of the cut guide portions and obstructs insertion of the cutting blade, for example, spike 5A other than tibial slit 7A, proximal fixing member 13A, main rod 1A, etc. (above, FIG. 12) Further, the shaft 6C other than the T-cut guide 7C, the T-rod guide 13C, etc. (above, FIG. 13), or the slider 13B, the fixture 5B, etc., other than the cutting head 7B (above, FIG. 14) do not get in the way. Moved to position or removed.

  In these conventional examples, each cut guide portion (tibial slit 7A, T-cut guide 7C, cutting head 7B) having a horizontal slit 7d has an abutment surface with respect to the tibial rough surface as an uneven surface of the tibial rough surface. Although the swivel angle (oscillation angle or yaw angle) around the Z-axis is adjustable so that it can be adjusted according to the pitch angle of the cut guide part relative to the horizontal ( It is not configured so that the X-direction forward tilt-back tilt angle or tilt angle around the Y axis can be adjusted.

JP 2016-49462 A Japanese Patent Laid-Open No. 7-184943 Utility Model Registration No. 3183614

  By the way, according to a standard operation procedure, the “horizontal plane” bone resection (osteotomy) of the proximal end side joint surface of the tibia using the above-described artificial knee joint replacement surgical instrument (tibial resection position guide device) The excision surface is tilted 0-3 ° on the varus side with reference to the “slope (tilt) of the upper joint surface” at the proximal end of the tibia and on the back side (back side) with respect to the horizontal plane. It is ideal to finish the surface so that it is inclined after about 7 °.

  However, in the conventional extramedullary type TKA tibial resection position guide device 40 (FIG. 12), the tibial slit is set so as to incline at a predetermined angle (hereinafter, incline backward) to the dorsal side with respect to the horizontal. 7A has only two to three types for every several degrees of the rearward tilt angle, and there is a problem that it is difficult to finely adjust the rearward tilt angle according to the patient's body shape, walking form, and the like.

  Similarly, the conventional intramedullary type TKA tibial resection position guiding device 60 (FIG. 13) and the UKA tibial resection position guiding device 50 (FIG. 14) also have a backward tilt angle (pitch angle) as in the extramedullary type. Although the adjustment of the rearward tilt angle of each cut guide portion (T-cut guide 7C, cutting head 7B) is not a stepwise adjustment, the reference cut guide positioning rod (in FIG. 13, arm portion 14C and shaft 6C). In FIG. 14, the angle of the main rod 1B) must be finely adjusted manually, and the rear tilt angle of the horizontal slit for actual cutting blade guidance after adjustment is as planned before the operation. There was a problem that it was difficult to confirm whether or not.

  Furthermore, in any type of tibial articular surface resection instrument, it takes time to set the surgical instrument before the operation and to set the posterior tilt angle thereafter, which takes time for the operation. In this respect, the current excision position guide has room for improvement.

  An object of the present invention is to provide an artificial knee joint replacement surgical instrument that can appropriately set the resection position and resection angle of the proximal joint surface of the tibia by simple adjustment in artificial knee joint replacement. That is.

The artificial knee joint replacement surgical instrument of the present invention includes a cut guide portion for guiding a cutting blade for excising the knee joint surface, and an arm portion for supporting the cut guide portion in the vicinity of the rough surface of the tibial proximal end of the tibia. And a base for supporting the arm portion, and a cut guide positioning rod used for fastening and fixing the cut guide portion to the rough tibial surface, along the longitudinal direction of the tibia A cut guide positioning rod provided on the proximal end side of the rod, and provided with a cut guide position adjusting portion for fitting and locking and positioning the base portion of the cut guide support portion;
Resection in which the base of the cut guide support part adjusts the posterior tilt angle of the cut guide part disposed at the tip of the arm part of the cut guide support part, which is the tilt angle in the direction from the tibia leading edge to the posterior edge with respect to the horizontal. An angle adjusting means is included.

  Further, in the artificial knee joint replacement surgical instrument of the present invention, the resection angle adjusting means includes a rotary tilt angle limiting mechanism using a cam, a dial that rotates in conjunction with the rotation of the tilt angle limiting mechanism, A ratchet means or a ball plunger capable of fixing a rearward tilt angle of the cut guide portion positioned at the tip of the arm portion at an arbitrary angle within a predetermined range in conjunction with the rotation of the dial; Features.

Further, in the artificial knee joint replacement surgical instrument of the present invention, the cut guide part is provided with a horizontal slit through which the cutting blade can be inserted in the horizontal direction, and the artificial knee joint replacement surgical instrument is the cut guide. A plurality of fastening pins for fastening and fixing the portion to the rough tibial surface,
The cut guide portion is fastened and fixed to the rough tibial surface by the plurality of fastening pins in a state where the horizontal slit is tilted backward in a range of 0 to 10 ° with respect to the horizontal. .

  According to the artificial knee joint replacement surgical instrument of the present invention, in the artificial knee joint replacement, the horizontal axis at the proximal end of the tibia of the cut guide portion having the cutting blade guide slit extending in the horizontal direction by a simple adjustment operation. It is possible to easily and appropriately set the inclination in the forward and backward tilt direction (pitch angle in the front-back direction of the tibia).

  In the artificial knee joint replacement surgical instrument of the present invention, the resection angle adjusting means includes a rotary tilt angle limiting mechanism using a cam (so-called scotch yoke mechanism), a rotary dial, In conjunction with the rotation angle of the dial, those equipped with ratchet means or a ball plunger capable of fixing the rearward tilt angle of the cut guide portion located at the tip of the arm portion at an arbitrary angle within a predetermined range, The surgeon can tilt the cut guide part in the backward tilt direction (pitch angle of the lowering) by slightly turning the dial installed in front of the surgeon, even with a slight tilt (back tilt) angle. Can be set smoothly. In addition, the setting of the rearward tilt angle of the cut guide portion can be performed more easily and accurately than when a conventional surgical instrument is used, and the time required for treatment can be shortened.

  Furthermore, the artificial knee joint replacement surgical instrument of the present invention further includes a plurality of fastening pins for fastening and fixing the cut guide portion to the rough tibial surface, and the cut guide portion is formed by the plurality of fastening pins. In the case where the horizontal slit is fastened and fixed in a state where it is tilted backward in the range of 0 to 10 ° with respect to the horizontal, it is possible to quickly set the surgical instrument before the operation and the subsequent tilt angle. It is possible to perform accurate bone resection according to the preoperative plan.

It is explanatory drawing explaining the usage type of the instrument for artificial knee joint replacement surgery for extramedullary type TKA in 1st Embodiment of this invention. FIG. 3 is an enlarged view of a proximal fixing member 3A and an arm portion 4A used in the extramedullary type TKA artificial knee joint replacement surgical instrument of the first embodiment. (A), (b), (c) is a partial sectional view seen from the left side and a partial sectional view seen from the front side, explaining the internal mechanism of the proximal fixing member 3A. (A) is the rearward tilt angle of the arm 0 ° (no rearward tilt), (b) is the rearward tilt angle of the arm 5 ° (intermediate position), and (c) is the rearward tilt angle of the arm 10 ° (maximum rearward tilt angle). Shows the state. It is explanatory drawing explaining the usage type of the instrument for artificial knee joint replacement surgery for extramedullary type TKA in 2nd Embodiment of this invention. (A) A side view of an intramedullary type TKA artificial knee joint replacement surgical instrument of the second embodiment, and (b) an enlarged view of a T-rod guide 3C and an arm part 4C used therein. (A), (b), (c) is a partial sectional view seen from the left side and a partial sectional view seen from the front side, explaining the internal mechanism of the T-rod guide 3C. , (A) T-cut guide rearward tilt angle 0 ° [no rearward tilt], (b) T-cut guide rearward tilt angle 5 ° [intermediate position], (c) T-cut guide rearward tilt angle. A state of an inclination angle of 10 ° [maximum rearward inclination angle] is shown. It is explanatory drawing explaining the usage type of the tibial joint surface excision instrument for UKA (single condyle) in 3rd Embodiment of this invention. It is the (a) upper surface perspective view and (b) lower surface perspective view of the slider 3B provided with the arm part 4B used for the tibial articular surface resection instrument for UKA of 3rd Embodiment. (A), (b), (c) are respectively a partial sectional view seen from the left side and a partial sectional view seen from the front side for explaining the internal mechanism of the slider 3B. ) Is the rearward tilt angle of 0 ° (no rearward tilt), (b) is the rearward tilt angle of the arm is 5 ° (intermediate position), and (c) is the rearward tilt angle of the arm is 10 ° (maximum rearward tilt angle). Show. It is a schematic block diagram which shows the structure of the main rod (upper side) and sub rod (horizontal bar) which are used for the tibial articular surface excision instrument for UKA. It is (a) top view, (b) front view, (c) bottom view which shows the structure of the resection guide (cutting head) used for the tibial articular surface resection instrument for UKA. It is a schematic block diagram which shows the whole structure of the conventional extramedullary type TKA tibial articular surface resection instrument corresponding to 1st Embodiment. It is a schematic block diagram which shows the whole structure of the conventional intramedullary type TKA tibial articular surface resection instrument corresponding to 2nd Embodiment. It is a schematic block diagram which shows the whole structure of the tibial joint surface excision instrument used for the conventional artificial knee joint single condyle replacement (UKA) corresponding to 3rd Embodiment.

  FIG. 1 is a perspective view showing a usage state of an extramedullary type TKA artificial knee joint replacement surgery instrument (tibial resection position guide device) according to the first embodiment of the present invention, and FIG. 2 shows the artificial knee joint. It is an enlarged view of 3 A of proximal fixing members and the arm part 4A which are used for the instrument for replacement surgery. FIG. 3 is a diagram for explaining the internal mechanism and operation of the proximal fixing member 3A. In addition, description of the direction in each figure is based on what is called "anatomical orthosis", and the front-rear (abdominal-dorsal) direction along the sagittal plane of the body is the X-axis direction (+: front abdominal side, -: Back side), the left-right direction along the coronal plane perpendicular to the sagittal plane is the Y-axis direction (+: right,-: left), and the vertical direction of the body along the "functional axis" is the Z-axis A direction (+: upward, −: downward) is assumed, and a cross section including the Y axis and the X axis is described as a “horizontal plane”.

  1 is an extramedullary (fixed) type TKA tibial resection position guide device for TKA. In total knee replacement (TKA), the tibia Before the operation for cutting (removing) the entire joint surface (total condyles) of the proximal end of the femur in a flat shape, the cut guide portion (tibial slit 7A) is moved to an appropriate position on the rough surface of the tibia T. It is used as a positioning guide (temporary temporary fixing device) for permanent fixing (fastening and fixing).

  The base part responsible for position fixing (gripping) of the tibial resection position guide device 10 includes, in order from the bottom in FIG. 1, an ankle clamp 8 that fixes the ankle while sandwiching it, and a rod guide part 9 that forms the lower receiver of the main rod 1A. And a main rod 1A which is an expansion / contraction part of the expansion / contraction rod, an adjustment (rotation) base 2A located above the main rod 1A, a proximal fixing member 3A attached to the top of the main rod 1A, and a tibial slit 7A 4A, and a spike shaft 6A and spike holding portion 6D protruding upward from the proximal fixing member 3A and a spike 5A for temporary fixation to the tibia above the main rod 1A It is configured.

  The middle part of the telescopic rod that connects the lower rod guide part 9 and the upper main rod 1A has a button part 9A that can adjust the length of the telescopic rod, that is, the height of the adjustment base 2A with one touch, and this button. A spring mechanism (not shown) for biasing the portion 9A is provided. The adjustment pedestal 2A on the upper part of the telescopic rod includes a sleeve portion and an adjustment nut. By rotating the adjustment pedestal 2A, the amount of protrusion of the main rod 1A above the adjustment pedestal 2A, that is, the Z axis with respect to the ankle clamp 8 of the proximal fixing member 3A. The height of the direction can be adjusted.

  The spike 5A is temporarily fixed so that the upper part of the main rod 1A does not wobble by driving a protrusion (spike) protruding downward from the lower surface (not visible in the figure) into the joint surface of the upper surface of the proximal end of the tibia. ing.

  A tibial slit 7A supported by a proximal fixing member 3A, which will be described later, is attached to the tip shaft portion of the arm portion 4A that protrudes upward from the front side (tibial side) of the proximal fixing member 3A. It has a block shape having a predetermined thickness in the direction, and has a horizontal slit 7d for cutting edge insertion / guide that penetrates in the front-rear direction (X-axis direction).

  A ball plunger as shown in FIG. 2 is disposed on the upper surface of the arm portion 4A, and the tibial slit 7A fitted to the tip of the arm portion 4A is locked by the ball plunger. ing. The main body of the block-shaped tibial slit 7A having a predetermined thickness is provided with a plurality of through holes into which fastening members such as screws and pins can be inserted, and the fastening members are inserted into these through holes. By being inserted and tightened, main fixation (fastening fixation) to the tibia (tibia rough surface) of the tibial slit 7A is performed.

  Here, the greatest feature of the extramedullary type TKA tibial resection position guiding device of the present embodiment is that the upper end of the main rod 1A disposed in the Z-axis direction along the functional axis is the spike 5A as described above. The tilt angle of the tibial slit 7A disposed in the vicinity of the rough tibial surface (pitch angle descending in the −X direction) can be changed even when the position is fixed by the ankle clamp 8 and the lower end is fixed by the ankle clamp 8. It is a point provided with a cutting angle adjusting means.

  This cutting angle adjusting means is incorporated in the proximal fixing member 3A as a rotary tilt angle limiting mechanism using a cam (so-called scotch yoke mechanism). That is, as shown in FIG. 3, the arm portion 4A of the proximal fixing member 3A is a “lever” with the intermediate support shaft portion P as a fulcrum, and one end on the distal end side (the left side in the drawing) is the tibial slit 7A. The other end of the base end side (right side in the figure) is connected to the crank Q of the Scotch-yoke mechanism that moves up and down as the dial 3d with scale (see FIG. 2) rotates.

  The crank Q converts the rotation operation of the dial 3d with a scale into the vertical movement of the other end (base end) of the arm portion 4A via the disk-like member R connected thereto. Further, a plurality of recesses are formed on the outer circumferential surface of the disk-shaped member R as shown in FIG. 3 so as to engage with ball plungers (not shown) disposed on the corresponding surfaces. It has become. As a result, the proximal fixing member 3A manually and accurately rotates the scaled dial 3d disposed on the front side thereof, thereby displaying the backward tilt angle of the tibial slit 7A on the dial 3d easily and accurately. Within a range of 0 ° to 10 °, it can be changed stepwise from 0.5 ° to 1.0 °.

  Therefore, the tibial resection position guide device 10 (artificial knee joint replacement surgery instrument) according to the present embodiment has a slight inclination (backward inclination) of the cut guide portion by simply turning the dial 3d installed in front of the operator. The angle difference can be set accurately and easily. In addition, this makes it possible to shorten the work (treatment) time compared to conventional surgical instruments.

  Next, although it is the same artificial knee joint replacement surgical instrument (TKA tibial resection position guide device), an intramedullary (fixed) type in which a positioning reference rod (T-rod 1C) is driven into the bone marrow cavity of the tibia explain.

  FIG. 4 is a perspective view showing a use state of an intramedullary type TKA artificial knee joint replacement surgery instrument (tibial resection position guide device) in the second embodiment of the present invention, and FIG. FIG. 5B is a side view of the artificial knee joint replacement surgical instrument, and FIG. 5B is an enlarged view around the T-rod guide 3C and the arm portion 4C used therein. FIG. 6 is a view for explaining the internal mechanism and operation of the T-rod guide 3C. In addition, the code | symbol with the same number is described to the structural member which has the function similar to the member demonstrated in the said 1st Embodiment (FIG. 1).

  4 is an intramedullary (fixed) type TKA tibial resection position guide device 30 for a total knee replacement (TKA). Prior to the operation of cutting (removing) all the joint surfaces (total condyles) of the proximal end of the tibia on the femur side, the arm portion 4C and the shaft 6C are suspended, and the position near the front side of the tibia T is located. After appropriately adjusting the rearward tilt angle of the temporarily fixed cut guide portion (T-cut guide 7C) with respect to the horizontal, the rearward tilt-adjusted T-cut guide 7C is permanently fixed to an appropriate position on the rough tibial surface ( Fastening and fixing).

  As shown in FIG. 4, the base portion of the tibial resection position guiding device 30 projects onto the tibial joint surface as a part of the T-rod 1C driven into the bone marrow cavity of the tibia T and the T-rod 1C. Attached to the scale part 2C, the T-rod guide 3C fitted into the protruding part (scale part 2C) of the T-rod 1C, the protruding arm part 4C for holding the T-cut guide 7C, and the arm part 4C The shaft holding portion 5C and a shaft 6C hanging from the shaft holding portion 5C and supporting the T-cut guide 7C and the T-cut guide holding portion 6E.

  The shaft holding portion 5C and the T-cut guide holding portion 6E are provided with position fixing tightening screws, and these positions and angles can be slid to be held and fixed at arbitrary positions. .

  Further, the T-cut guide holding portion 6E inserted through the shaft 6C and the T-cut guide 7C supported by the shaft holding portion 5C inserted through the arm portion 4C penetrate in the front-rear direction (X-axis direction). A plurality of through-holes through which a horizontal slit 7d for blade insertion / guide and a fastening member such as a screw or a pin can be inserted are provided, and the fastening member is inserted into the through-hole to be tightened. -Final fixation (fastening fixation) to the tibia (tibial rough surface) of the cut guide 7C is performed.

  The feature of the intramedullary type TKA tibial resection position guide device 30 in this embodiment is the same as that of the first embodiment in that the T-cut guide 7C disposed in the vicinity of the rough tibial surface before the fastening member is fixed. It is the point provided with the cutting angle adjustment means which can change a back inclination angle (pitch angle which goes down toward -X direction) continuously.

  In the case of the second embodiment, this cutting angle adjusting means is formed in the T-rod guide 3C fitted into the scale portion 2C of the T-rod 1C, and is similar to the cam in the first embodiment. Is incorporated as a rotary tilt angle limiting mechanism (so-called Scotch-yoke mechanism).

  That is, as shown in FIG. 6, the arm portion 4C of the T-rod guide 3C is a “lever” with the support shaft portion P as a fulcrum, and the tip side (right side in the drawing) is the T-cut guide 7C. The base end side (the left side in the figure) is connected to a crank Q that moves up and down as the dial 3d with scale (see FIG. 5B) rotates.

  The crank Q converts the rotating operation of the dial 3d with a scale into the vertical movement of the arm portion 4C via the disk-shaped member R connected thereto. Further, a plurality of recesses are formed on the outer circumferential surface of the disk-shaped member R as shown in FIG. 6 so as to engage with ball plungers (not shown) disposed on the corresponding surfaces. It has become. As a result, the T-rod guide 3C allows the dial 3d to easily and accurately turn the rearward tilt angle of the T-cut guide 7C by manually rotating the dial 3d with a scale disposed on the front side thereof. Within the displayed range of 0 ° to 10 °, it can be changed in steps of 0.5 ° to 1.0 °.

  In addition, the tibial resection position guide device 10 (artificial knee joint replacement surgery instrument) of the present embodiment has a slight inclination (backward inclination) of the cut guide portion by simply turning the dial 3d installed in front of the operator. The angle difference can be set accurately and easily. Therefore, the artificial knee joint replacement surgery instrument of this embodiment can shorten the work (treatment) time as compared with the conventional surgical instrument.

  Next, a description will be given of a third embodiment relating to a tibial articular surface resecting instrument for tidal bone (tibial resection position guide device) used in single knee condyle replacement (UKA).

  FIG. 7 is a perspective view showing a use state of a UKA artificial knee joint replacement surgical instrument (tibial resection position guide device) according to a third embodiment of the present invention, and FIG. 8 shows the artificial knee joint replacement surgical instrument. It is an enlarged view of the slider 3B and the arm part 4B used for FIG. FIG. 9 is a diagram for explaining the internal mechanism and operation of the slider 3B.

  The tibial resection position guide device 20 of the present embodiment, which is shown in FIG. 7 in its entirety, is one of the joint surfaces on the proximal end side (femoral side) of the tibia T of the knee joint in the artificial knee joint condyle replacement (UKA). A resection position guide instrument used when resecting (unicondyle), and a base portion fixed along the bone axis (Z axis) of the tibia T and the proximal portion of the tibia T as shown in the figure A cut guide portion (cutting head 7B) positioned so as to be in contact with the end (on the + Z side and on the upper side).

  The base portion includes, in order from the bottom in FIG. 7, an ankle clamp 8 that sandwiches and fixes the ankle, a rod guide portion 9 that forms a lower support of the main rod 1 </ b> B, a main rod 1 </ b> B that is a stretchable portion of the telescopic rod, An adjustment (rotation) pedestal 2B positioned above the rod 1B, a fixture 5B for temporarily fixing the adjustment pedestal 2B to the front surface (tibial rough surface) of the tibia T, and a horizontal fixed to the upper part of the adjustment pedestal 2B And a sub-rod 6B, a slider 3B that supports the cutting head 7B, an arm portion 4B, and the like.

  As in the first embodiment, the length of the telescopic rod, that is, the height of the adjusting pedestal 2B can be touched at the middle of the telescopic rod that connects the lower rod guide 9 and the upper main rod 1B. An adjustable button portion 9A and a spring mechanism (not shown) for biasing the button portion 9A are provided. The adjustment pedestal 2B above the telescopic rod includes a sleeve portion and an adjustment nut. By rotating the adjustment pedestal 2B, the amount of protrusion of the main rod 1B above the adjustment pedestal 2B, that is, the horizontal sub rod 6B and the slider 3B inserted therethrough. The height in the Z-axis direction with respect to the ankle clamp 8 can be adjusted.

  Further, as shown in FIG. 10, the sub rod 6B is a member formed in the shape of a square bar, and is fixed in a state of being inserted through a through hole provided in a protruding portion of the main rod 1B on the upper side of the adjustment base 2B. ing. The sub rod 6B is disposed so as to extend in the left-right direction of the knee joint along a horizontal plane orthogonal to the main rod 1B of the telescopic rod.

  Moreover, the upper part of the main rod 1B does not wobble by driving a screw (fastening member) protruding from the front surface (not visible in the figure) of the fixture 5B into the front surface (tibial rough surface) of the proximal end of the tibia. And temporarily fixed.

  Further, a cutting head 7B supported by a slider 3B, which will be described later, is fitted and attached to the distal end shaft portion 4d of the arm portion 4B protruding upward from the front side (tibial side) of the slider 3B. 11 (b) is a front view, (a) is a top view, and (c) is a bottom view, and is a block shape having a predetermined thickness in the vertical direction. The part 24 is integrally formed, and has a horizontal slit 7d and a vertical slit 7e for cutting edge insertion / guide, which penetrate in the front-rear direction (X-axis direction).

  A through hole in the horizontal (X-axis) direction for attaching the fastening screw 21 (not visible because the screw 21 is fitted in the drawing) is formed in the lower portion of the base portion 22, and as shown in FIG. 11C. A hole 25 is provided on the bottom surface of the base portion 22 for fitting a shaft support portion (tip shaft portion 4d) of the arm portion 4B described later.

  In addition, as shown in FIG. 11B, four holes 26 that pass through the bending portion 23 in the front-rear (X-axis) direction are provided in the lower portion of the bending portion 23. A screw for fixing the cutting head 7B to the front surface of the tibia T is inserted.

  The horizontal slit 7d is provided as a guide portion that guides the cutting blade so that the cutting blade (saw blade or blade) can cut a desired position at the proximal end of the tibia T. Is formed in a width that can be inserted. The vertical slit 7e is also a guide part for guiding the cutting blade, and the groove width is formed to be a groove width through which the cutting blade can be inserted, similarly to the horizontal slit 7d.

  The cutting head 7B is fixed by fitting the cylindrical tip shaft portion 4d of the arm portion 4B into a hole 25 provided on the lower surface (bottom surface) of the cutting head 7B and tightening it with a screw 21. Therefore, by loosening the screw 21, the entire cutting head 7B can be rotated in the left-right direction along the horizontal plane to be aligned.

  The UKA tibial resection position guide device 20 configured as described above is also characterized in that the positions of the main rod 1B and the sub rod 6B arranged in the Z-axis direction along the functional axis are fixed by the fixture 5B. Even when the lower end is fixed in position by the ankle clamp 8, the resection angle adjusting means can change the backward tilt angle (pitch angle descending in the -X direction) of the cutting head 7B disposed in the vicinity of the rough surface of the tibia It is a point equipped with.

  As in the first embodiment, this cutting angle adjusting means is incorporated in the slider 3B as a rotary tilt angle limiting mechanism (so-called Scotch-yoke mechanism) using a cam, as shown in FIG. Further, the arm portion 4B of the slider 3B is a “lever” having the intermediate support shaft portion P as a fulcrum, and the distal end shaft portion 4d on the distal end side (the left side in the drawing) is connected to the cutting head 7B. The other end (shown on the right side) is connected to a crank Q of a scotch-yoke mechanism that moves up and down as the dial 3d with scale (see FIG. 8) rotates.

  The crank Q converts the rotation operation of the dial 3d with a scale into the vertical movement of the other end (base end) of the arm portion 4A via the disk-like member R connected thereto. Furthermore, a plurality of recesses are formed on the outer circumferential surface of the disk-shaped member R as shown in FIG. 9 so as to engage with ball plungers (not shown) disposed on the corresponding surfaces. It has become. As a result, the slider 3B manually and accurately rotates the scaled dial 3d disposed on the front side of the slider 3B, so that the backward tilt angle of the cutting head 7B is displayed from 0 ° displayed on the dial 3d. Within a range of 10 °, it can be changed stepwise from 0.5 ° to 1.0 °.

  That is, the conventional UKA tibial resection position guide device 50 has means for adjusting the vertical (front-rear) tilt of the cutting head 7B along the sagittal plane of the body, as shown in FIG. First, in order to adjust the inclination of the cutting head 7B and the horizontal slit 7d with respect to the horizontal plane, such as forward inclination and backward inclination, the fixture 5B is released (fastened), and the main rod 1B and the sub rod 6B are attached to the tibia T. There was no choice but to adjust the angle.

  On the other hand, in the UKA tibial resection position guide apparatus 20 of this embodiment, as shown in FIG. 7, the slider 3B that supports the cutting head 7B has an inclination angle of the arm portion 4B extended from the slider 3B. Arm angle adjusting means for changing is provided. Thereby, the tibial resection position guide device 20 for UKA of this embodiment sets the inclination angle (rear inclination angle θ) of the arm portion 4B from the horizontal plane to 0 ° [horizontal, FIG. 9 (a)] to 10. It was possible to change to [the state of FIG. 9 (c)].

  For example, in the case of FIG. 9A in which the base portion Q of the arm portion 4B is at the bottom dead center of the crank, the cutting head 7B exhibits a backward tilt angle θ = 0 °, and the base portion Q of the arm portion 4B is In the case of FIG. 9C at the top dead center, the cutting head 7B shows a backward tilt angle θ = 10 °. Further, in the state of FIG. 9B, which is an intermediate point of rotation and an intermediate point of the crank upper and lower sides, the backward tilt angle θ of the cutting head 7B is 5 °. Further, the synchronous rotation of the scaled dial 3d and the disk-shaped member R is not provided with a limiter, and can continue to rotate without limitation in the same direction.

  In addition, the dial 3d of each embodiment is arrange | positioned in the front side which is an operator side, and the rotating shaft of the dial 3d and the disk-shaped member R is a back | inner side direction (X-axis direction minus | minus) seeing from an operator. Side). This arrangement prevents the operation of the operation dial 3d from being hindered even when there is no space left and right.

  As described above, a plurality of hemispherical concave portions are formed at a predetermined pitch on the outer peripheral surface of the disk-shaped member R, and a ball plunger (not shown) is provided at a position corresponding to the outer peripheral surface. At the same time, a scale corresponding to each of the hemispherical recesses is marked on the surface of the dial 3d in increments of 0.5 ° or 1 °, for example. As a result, the desired rearward tilt angle can be set quickly and accurately.

  With the above configuration, the tibial resection position guiding device of the present invention is disposed in the vicinity of the rough tibial surface even when the upper end and the lower end of the base portion disposed in the Z-axis direction along the functional axis are fixed. It is possible to change the rearward tilt angle (pitch angle descending in the −X direction) of the cut guide portion.

  In addition, the adjustment of the tilt can be performed by using the rotary dial facing the front of the operator who is the operator, using the scales engraved as a guide, so even if there is no margin on the left and right of the operative field, The backward tilt angle can be easily reproduced or readjusted. Therefore, the tibial resection position guide device of the present invention appropriately sets the resection angle of the proximal tibia joint surface by simple adjustment in artificial knee joint condyle replacement, and accurately resects the joint surface as scheduled. can do. In addition, the work (treatment) time can be shortened as compared with conventional surgical instruments.

  As mentioned above, although embodiment of this invention was described in detail, this invention is not limited to the above-mentioned embodiment, A various change, improvement, etc. are possible in the range which does not deviate from the summary of this invention. is there.

  For example, the rear tilt angle fixing structure using the ball plunger can be replaced by another mechanism such as a ratchet mechanism.

  Further, in the above embodiment, the case where the backward tilt angle of the cutting head can be adjusted in the range of 0 to 10 ° is exemplified, but the adjustment range of the subsequent tilt angle may be capable of tilting backward at a larger angle, Or it is good also as a structure in which the forward tilt to the near side (it is a minus range if it says in a back tilt angle) is possible.

1A Main rod 2A Adjustment base 3A, 13A Proximal fixing member 3d Dial 4A, 14A Arm part 5A Spike 6A Spike shaft 6D Spike holding part 7A Tibial slit 7d Slit (horizontal)
8 Ankle clamp 9 Rod guide part 9A Button part 1B Main rod 2B Adjustment base 3B, 13B Slider 4B, 14B Arm part 5B Fixture 6B Sub rod (lateral bar)
7B Cutting head 7e Slit (vertical)
1C T-rod 2C Scale part 3C, 13C T-rod guide 4C, 14C Arm part 5C Shaft holding part 6C Shaft 6E T-cut guide holding part 7C T-cut guide 10, 20, 30, 40, 50, 60 Tibial resection Position guide device T Tibia P Support shaft part Q Crank R Disk-shaped member

Claims (3)

A cut guide portion for guiding a cutting blade for excising the knee joint surface;
A cut guide support portion comprising an arm portion for supporting the cut guide portion in the vicinity of the rough surface of the tibial bone at the leading edge of the proximal end of the tibia and a base portion for supporting the arm portion;
A cutting guide positioning rod used for fastening and fixing the cutting guide portion to the rough surface of the tibia, which is disposed along a longitudinal direction of the tibia, and on the proximal end side of the rod, the cutting guide A cut guide positioning rod provided with a cut guide position adjusting portion for fitting, locking and positioning the base portion of the support portion, and
Resection in which the base of the cut guide support part adjusts the posterior tilt angle of the cut guide part disposed at the tip of the arm part of the cut guide support part, which is the tilt angle in the direction from the tibia leading edge to the posterior edge with respect to the horizontal. An artificial knee joint replacement surgical instrument comprising an angle adjusting means. The resection angle adjusting means is
A rotary tilt angle limiting mechanism using a cam, and a dial that rotates in conjunction with the rotation of the tilt angle limiting mechanism;
A ratchet means or a ball plunger capable of fixing a rearward tilt angle of the cut guide portion positioned at the tip of the arm portion at an arbitrary angle within a predetermined range in conjunction with the rotation of the dial; The artificial knee joint replacement surgical instrument according to claim 1, wherein The cut guide part is provided with a horizontal slit through which the cutting blade can be inserted in the horizontal direction,
A plurality of fastening pins for fastening and fixing the cut guide portion to the rough tibial surface;
The cut guide portion is fastened and fixed to the rough tibial surface by the plurality of fastening pins in a state where the horizontal slit is tilted backward in a range of 0 to 10 ° with respect to the horizontal. The artificial knee joint replacement surgical instrument according to claim 2.

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