JP5252968B2 - Femoral component retention device - Google Patents

Description

  The present invention relates to a holding device for holding a femoral component when the femoral component for an artificial knee joint is attached or detached.

  In the artificial knee joint replacement surgery, provisional reduction is one of the important items in the surgical technique. Temporary reduction is the same as the femoral component before the member (called “femoral component”) installed in the distal femur of the artificial knee joint is actually installed on the bone. A temporary femoral component is temporarily fixed to the distal femur to see if it performs the function of the joint. In many cases, a holder for holding the femoral component is used for installing and removing the simulated femoral component and for installing the actual femoral component. As the holder, a holder having means for contacting the surface of the medial condyle and the lateral condyle of the femoral component and means for grasping the intercondylar notch along the inner contact surface is known (for example, see Patent Document 1). .) However, this holder has the disadvantage that it cannot be used for femoral components without intercondylar notches.

  Therefore, a holder (femoral component holding device 1001 shown in FIG. 22) that can hold various femoral components regardless of the presence or absence of intercondylar notches is used. While holding the inner and outer edges of the femoral component 90 between the pair of arms 1010, the holding device 1001 hangs the hook 1016 at the tip of the arm 1010 on the inner surface of the femoral component 90, and further between the arms 1010. By pressing the outer surface of the femoral component 90 with the arranged table 1020, the femoral component 90 can be reliably held.

After holding the femoral component 90 in the holding device 1001, the femoral component 90 is installed as shown in FIG. The operator holds the grip 1050 of the holding device 1001, places the femoral component 90 on the distal portion 102 of the cut femur 100, and hits the rear end portion (table dial 1028) of the holding device 1001 with a hammer. The femoral component 90 is driven into the distal femur 102.
In the case of temporary reduction, the simulated femoral component 90 fitted in the distal femur 102 is later removed, and the holding device 1001 is also used for the removal.

To retain the femoral component 90 in retainer 1001 and sequentially operating two dial (arm dial 1018 and the dust table dial 1028). As a detailed procedure, first, the arm dial 1018 is loosened, the arm 1010 is opened, the table dial 1028 is loosened, and the table 1020 is moved backward in the grip 1050 direction. Next, the femoral component 90 is disposed between the pair of arms 1010 and the table 1020, and the arm dial 1018 is tightened to close the arm 1010. At this time, the arm dial 1018 is tightened while finely adjusting the position of the femoral component 90 so that the hook 1016 of the arm 1010 is hooked at a predetermined position of the femoral component 90. Then, the table dial 1028 is tightened so that the table 1020 protrudes toward the femoral component 90 and the outer surface of the femoral component 90 is pressed.
JP-A-6-169930

In the conventional femoral component holding device 1001, since it is necessary to operate two dials, it takes time to hold and release the femoral component 90, and it is difficult to perform a quick surgical operation.
Therefore, an object of the present invention is to provide a holding device that can hold and release the femoral component 90 in a short time.

The holding device of the present invention is a holding device for holding a curved femoral component for a knee prosthesis having an outer surface having a right condyle and a left condyle, and an inner surface opposite to the outer condyle. A pair of arms having a hook to sandwich the femoral component from the left and right; a table positioned between the pair of arms; a free end and a fixed end; and a lever interlocking with the arm and the table; A cylinder in which the fixed end of the lever is rotatably supported, a slide pipe coupled to the pair of arms, in which the cylinder is slidably inserted, and the lever and the slide pipe. anda pair of connecting plates for connecting said connecting plate has one end rotatably supported between the free end and the fixed end of the lever, the other end the The slide pipe is slidably moved along the cylinder via the connection plate by being movably held by the ride pipe and tilting the lever toward the cylinder around the fixed end of the lever. The pair of arms coupled to the slide pipe can be brought close to each other, the femoral component is sandwiched from the left and right by the pair of arms, and the outer surface of the femoral component is pressed by the table And when the pair of hooks are hooked on the left and right edges of the inner surface of the femoral component, while the lever is moved from the start position to the end position where the lever is tilted toward the cylinder. It is characterized by being performed.

  According to the present invention, since the femoral component can be held by operating the arm or the table only by moving the lever from the start position to the end position, the time required to hold the femoral component 90 compared to the conventional one. Can be shortened.

  Specifically, in order to press the femoral component with the table and hold the femoral component with the arm, the holding device moves the table relatively close to the femoral component by operating the lever, and moves the arm. Can be close to each other.

The holding device includes a cylinder in which the lever is rotatably supported, and the end position of the lever is in a state where the lever is tilted toward the cylinder, so that the lever can be operated with one hand. Is excellent. Furthermore, since the lever and the cylinder can be grasped together after the lever is tilted to the cylinder side, it is easy to handle the holding device after holding the femoral component.

  Specifically, the holding device further includes a shaft that is slidably inserted into the cylinder, the shaft having the table fixed at one end thereof, and a slide pipe through which the cylinder is slidably inserted. The pair of arms are coupled to the slide pipe, and the holding device further includes a pair of connection plates that connect the lever, the shaft, and the slide pipe, and one end of the connection plate is connected to the lever. The other end of the connection plate is movably held by the shaft and the slide pipe, and the lever is tilted in the direction of the cylinder. The shaft and the slide pipe are slid along the cylinder via the connection plate.

  As a specific example of the connection plate, a slide pin that moves in the direction of the table is coupled to the other end of the connection plate, and the shaft includes a hole through which the slide pin is inserted, and the slide The pipe is arranged on the table side with respect to the slide pin, a spring is arranged between the slide pipe and the slide pin and around the cylinder, and the lever is tilted in the direction of the cylinder, The shaft can be slid in the direction of the table via a slide pin, and the slide pipe can be slid in the direction of the table via the slide pin and the spring.

  The lever has a lever side uneven portion on an inner surface facing the cylinder, and has a slide pipe side uneven portion meshing with the lever side uneven portion on the surface facing the lever, and the lever When moving to the end position, it is preferable that the lever side unevenness and the slide pipe side unevenness mesh with each other to fix the slide pipe and the cylinder. When the slide pipe is fixed, the arm is also fixed, so that the femoral component can be firmly held from the left and right.

  Further, it is preferable that the femoral component is hooked by the hook before being pressed by the table because the femoral component can be held by the hook when pressed by the table.

  It is preferable that an adjustment screw for adjusting the longitudinal position of the table and the shaft is fixed to the cylinder side of the table. Since the distance between the hook and the table can be adjusted using an adjustment screw, the femoral component used can be held securely.

  The adjustment screw has a plurality of adjustment holes formed on a surface facing the cylinder, the cylinder has a protrusion at a position corresponding to the adjustment hole, and the table springs in the cylinder direction. Preferably, after the adjustment screw is rotated and the position of the table is adjusted, the table is moved to the cylinder side and the protrusion is inserted into the adjustment hole. As a result, the table is pulled in the opposite direction to the cylinder, the projection is removed from the adjustment hole of the adjustment screw, the adjustment screw is rotated to adjust the position of the table, and the projection is inserted into the adjustment hole. Thus, the position of the table can be easily adjusted. Further, the spring bias does not cause the projection to come out of the adjustment hole after the table position is adjusted.

  With the holding device of the present invention, it is possible to hold and release the femoral component in a short time compared to the conventional case, which is suitable for quick surgical operation.

<Embodiment 1>
1 and 2 show a femoral component holding device 1 according to the present embodiment. FIG. 1 shows a state before holding the femoral component 90 for the left knee, and FIG. 2 shows a state after holding. In the present specification, terms including “proximal” and “distal” (for example, “proximal side”, “proximal end”, etc.) are used in the description of the holding device 1. In the document, “proximal” and “distal” mean “proximal” closer to the operator and “distal” away from the operator when the operator grasps the femoral component holding device 1. Is. For example, the arm 10 and the table 20 that hold the femoral component 90 are arranged at the “distal end” of the holding device 1.

The holding instrument 1 has a pair of arms 10 for holding the femoral component 90 from the left and right sides, and a table 20 positioned between the pair of arms at the distal end, and a top plate for hammer driving. 80 at the proximal end.
An intermediate portion of the holding device 1 is a grip portion for the operator to grip, and a shaft 50 and a cylindrical cylinder 40 through which the shaft 50 is inserted are arranged. Further, a spring 70 and a slide pipe 60 are disposed on the outer periphery on the distal side of the cylinder 40. The shaft 50, the cylinder 40 and the slide pipe 60 are not fixed and are slidable with respect to each other. Further, the cylinder 40 and the spring 70 are not fixed and are slidable.
A lever 30 is rotatably supported (axially supported) on the proximal side of the holding device 1, and the lever 30 and the slide pipe 60 are connected by a connection plate 32.

Each component of the holding device 1 will be described in detail below with reference to FIGS.
3 and 4 illustrate the cylinder 40 and the lever 30. FIG. The cylinder 40 is a cylindrical member having a shaft insertion hole 46 inside. On the outer surface near the distal end of the cylinder 40, two rods 44 protrude in opposite directions along a straight line perpendicular to the axial direction of the cylinder 40. Near the center of the cylinder 40, two through holes 42 extending in the axial direction of the cylinder 40 are formed at positions facing each other. A slide pin 34 is disposed so as to pass through the two through-holes 42 and to be orthogonal to the axial direction of the cylinder 40. The slide pin 34 is slidable along the longitudinal direction of the through hole 42 (that is, the axial direction of the cylinder 40).

The lever 30 is pivotally supported by a shaft pin 36 near the proximal end of the cylinder 40. Of the end portions of the lever 30, an end portion pivotally supported by the cylinder 40 is a fixed end 35, and an end portion capable of rotating in the direction of the arrow R ₁ is a free end 33. The lever 30 of the present embodiment has a configuration in which one strip and two strips arranged in parallel are partially connected in a U-shaped cross section. One strip extends to the free end 33 and the two strips are connected to the fixed end 35. Between the fixed end 35 and the free end 33, the proximal ends of the two connection plates 32 are pivotally supported by pins 322 on each of the two strips described above. The distal end of each connection plate 32 is pivotally supported by screws 38 on both sides of the slide pin 34.

From the state of FIG. 1, when rotation of the lever 30 in the direction of arrow R _1, the connection plate 32 which has an angle with respect to the axial direction of the cylinder 40, is substantially parallel with the axial direction of the cylinder 40 ( (See FIG. 2). At this time, the slide pin 34 slides from the proximal position to the distal position of the through slot 42.
Conversely, if the rotation operation from the state shown in FIG. 2 the lever 30 in the arrow R ₂ direction, connecting plate 32 returns to the state in which an angle to the axial direction of the cylinder 40, the slide pin 34, the through long hole 42 Slide from the distal position to the proximal position (FIG. 1).

  FIG. 5 illustrates the shaft 50, the table 20, and the top plate 80. In the present embodiment, the shaft 50 is a round bar-like member, and the table 20 is fixed to the distal end, and the top plate 80 is fixed to the proximal end. The table 20 and the shaft 50 are connected by a screw 53 (see FIGS. 9 to 11), and the longitudinal position of the table 20 can be adjusted by the screw 53. A through hole 52 extending in the axial direction of the shaft 50 is formed near the center of the shaft 50. When the respective components are assembled, the position of the through slot 52 substantially coincides with the positions of the two through slots 42 of the cylinder 40 shown in FIG. It is slidably inserted.

  The table 20 includes a table plate 22 made of a rigid body and a buffer pad 24 made of an elastic body. Further, the cushion pad 24 has a convex portion 26 so as to fit a recess (intercondylar fossa) between a right condyle (a medial condyle in the left knee) and a left condyle (a lateral condyle in the left knee) of the femoral component 90. Is formed.

  FIG. 6 illustrates the slide pipe 60. The slide pipe 60 is a cylindrical member having a cylinder insertion hole 66 inside. Two branch plates 64 extending parallel to the proximal direction are provided on the proximal side of the slide pipe 60. Each branch plate 64 is formed with a through hole 642, and both ends of the slide pin 34 shown in FIG. 3 are slidably inserted.

  Near the center of the slide pipe 60, two inclined plates 62 that protrude from the outer surface of the slide pipe 60 and are inclined toward the distal direction are formed. The inclined plate 62 is arranged such that the main surface is parallel to the proximal-distal direction and the main surfaces of the two inclined plates 62 are coplanar. On both surfaces of the distal end of the inclined plate 62, pins 622 and 624 protruding in a direction orthogonal to the main surface of the inclined plate 62 are formed.

  The cylinder insertion hole 66 of the slide pipe 60 has a proximal inner diameter larger than the distal inner diameter, and a spring 70 can be inserted into the expanded diameter portion (see FIGS. 1 and 2). Further, a step corresponding to the inner diameter difference between the proximal side and the distal side is formed on the inner surface of the cylinder insertion hole 66.

Although FIG. 7 shows a pair of arms 10, this can be configured by arranging the same arms 10 in mirror symmetry. The individual arms 10 will be described below.
In the present embodiment, a hook 16 is formed at the tip (distal end) of the arm 10 and extends in a direction perpendicular to the proximal-distal direction. Two inclined plates 12 parallel to the proximal-distal direction are formed on the proximal side of the arm 10 and extend in a direction inclined with respect to the proximal-distal direction. Each inclined plate 12 is formed with through holes 122 and 124 extending along the extending direction of the inclined plate 12. A rod guide 14 having a rod insertion hole 142 is formed near the center of the arm 10 and extends in a direction perpendicular to the proximal-distal direction. When assembled as shown in FIGS. 1 and 2, the pins 622 and 624 of the slide pipe 60 are slidably inserted into the through elongated holes 122 and 124, and the rod 44 of the cylinder 40 is slidable into the rod insertion hole 142. It is inserted.

FIG. 8 illustrates a spring 70 for inserting the distal end side of the cylinder 40. The illustrated spring 70 is a general coil spring and has an inner diameter through which the cylinder 40 can be inserted.
When assembled as shown in FIGS. 1 and 2, the distal end of the spring 70 is inserted into the cylinder insertion hole 66 of the slide pipe 60 from the proximal side, and a step 68 formed on the inner surface of the cylinder insertion hole 66 (FIG. 6) and the proximal end of the spring 70 contacts the distal end of the connecting plate 32.

The operation of the holding device 1 will be described with reference to FIGS. In addition, in order to make it easy to understand the change in the internal structure of the holding device 1, some of the components shown in FIGS. 9 to 12 are shown in cross section.
FIG. 9 shows a state before the femoral component 90 is held, and the lever 30 is in the “starting position” before the operation of the holding device starts. The free end 33 of the lever 30 is separated from the cylinder 40, in other words, the free end 33 is located on the proximal side. The slide pin 34 connected to the lever 30 via the connection plate 32 also slides in the through-hole 42 of the cylinder 40 and is located on the proximal side. When the slide pin 34 comes into contact with the proximal end of the through hole 42 of the cylinder 40, the lever 30 is in the most raised state, and the free end 33 cannot be separated from the cylinder 40 any more.

The slide pin 34 is also inserted into the through long hole 642 of the slide pipe 60 and the through long hole 52 of the shaft 50. By sliding the slide pin 34 proximally, different actions are performed for each through long hole. Effect. The relationship between the slide pin 34 and each through long hole will be described.
In the relationship between the slide pin 34 and the through long hole 642 of the slide pipe 60, the slide pin 34 is spring-biased proximally by the spring 70 and abuts on the proximal end of the through long hole 642. When the slide pin 34 is slid to the proximal side, the slide pin 34 presses the proximal end of the through long hole 642, and the slide pipe 60 slides to the proximal side.
With respect to the relationship between the slide pin 34 and the through long hole 52 of the shaft 50, the slide pin 34 is not particularly limited in the through long hole 52 and is in a freely slidable state.

As described above, when the slide pipe 60 slides proximally by the slide pin 34, the pair of arms 10 can be opened. When the slide pipe 60 slides proximally, the inclined plate 62 and the pin 624 simultaneously move proximally. Since the pin 624 is inserted into the through long hole 124 formed in the inclined plate 12 of the arm 10, the arm 10 is also moved by the movement of the pin 624. However, since the arm 10 is limited to movement in the inner and outer directions by the rod 44 inserted through the rod insertion hole 142, the pin 624 slides in the through long hole 124 of the inclined plate 12 in an oblique direction. The arm 10 moves in a direction away from the cylinder 40 in the inner and outer directions, that is, the direction in which the pair of arms 10 are opened.
That is, by moving the free end 33 of the lever 30 away from the cylinder 40 (raising the lever 30), the slide pipe 60 slides in the proximal direction and the arm 10 is opened.

  Further, when the shaft 50 is slid proximally by the slide pin 34, the table 20 fixed to the distal end of the shaft 50 is also moved proximally. That is, the shaft 50 and the table 20 move in the proximal direction by moving the free end 33 of the lever 30 away from the cylinder 40 (raising the lever 30).

Figure 10 is a state in which the free end 33 of the lever 30 in FIG. 9 was rotated and moved in the R ₁ direction (a state of tilting the lever 30 in the cylinder 40 direction). The most different from FIG. 9 is that the slide pin 34 has moved to the distal side, so that the slide pipe 60 has also been slid to the distal side. is there.
The slide pipe 60 slides by the movement of the slide pin 34 as follows. A connecting plate 32 and a spring 70 are disposed between the slide pin 34 and the slide pipe 60. As the slide pin 34 moves distally, the distal end of the connection plate 32 presses the proximal end of the spring 70 distally. Since the proximal end of the spring 70 is in contact with the step 68 formed on the inner surface of the cylinder insertion hole 66 of the slide pipe 60, the pressing force applied to the distal end of the spring 70 is The slide pipe 60 is slid in the distal direction through the step 68 that is in contact with.

  As described above, the arm 10 can be moved inward and outward by sliding the slide pipe 60. When the slide pipe 60 slides to the distal side as shown in FIG. 10, the pin 624 slides obliquely toward the distal side through the through-hole 124 of the arm 10, and the pair of arms 10 has the inner and outer sides. The direction moves toward each other, that is, toward the cylinder 40. As a result, the arm 10 can hold the right edge (inner edge in the left knee) 92 and the left edge (outer edge in the left knee) 94 of the femoral component 90. In addition, when the recessed part 95 which latches the hook 16 of the arm 10 is formed in the inner edge part 92 and the outer edge part 94 of the femoral component 90, it is careful to align the hook 16 with the recessed part 95. .

  Note that when the femoral component 90 is pressed by the table 20, the hook 16 of the arm 10 is securely hooked in the recess 95 of the femoral component 90. In a state where the femoral component 90 is in contact with the table 20, it is preferable to adjust the distance between the table 20 and the hook 16 so that the hook 16 is substantially aligned with the recess 95.

Figure 11 is a further free end 33 a state in which the rotation has R ₁ direction of the lever 30 in FIG. 10 (further Killed condition lever 30). The most different from FIG. 10 is that the slide pin 34 has moved distally and has compressed the spring 70.
As the slide pin 34 moves distally, the distal end of the spring 70 is pressed distally. However, at the time of FIG. 10, the arm 10 holds the femoral component 90 and cannot be closed any further, so that the slide pipe 60 cannot slide distally. Therefore, the proximal end of the spring 70 is fixed by the step 68 of the slide pipe 60. Therefore, the spring 70 is compressed by the pressing force applied to the distal end of the spring 70. By providing the spring 70, femoral components having different widths can be accommodated, and any width femoral component can be firmly held.

And Figure 12 is rotated and moved further R ₁ direction free end 33 of the lever 30 in FIG. 11, which is the most close state to the cylinder 40 (a state where the lever 30 completely defeated). At this time, the lever 30 is in the “end position” where the operation of the holding device has been completed. The most different from FIG. 10 is that the slide pin 34 has moved distally, pushing the distal end of the through-bore 52 of the shaft 50 distally, thereby causing the table 20 to move to the femur. Approaching component 90 and table 20 pressing outer surface 98.
Similar to FIG. 11, the spring 70 is further compressed by the distal movement of the slide pin 34. Then, the slide pin 34 comes into contact with the distal end of the through long hole 52 of the shaft 50. When the slide pin 34 further moves to the distal side, the slide pin 34 presses the distal end of the through slot 52 of the shaft 50 to the distal side, and the shaft 50 slides to the distal side. Then, the table 20 fixed to the distal end of the shaft 50 also moves to the distal side together with the shaft 50. The femoral component 90 is already held between the inner and outer edges by the arm 10 and is hooked on the inner surface by the hook 16, but is further securely held by the outer surface 98 being pressed by the table 20.

As shown in FIGS. 9 to 12, the holding device 1 of the present embodiment holds the femoral component 90 from the left and right by a pair of arms 10 (FIG. 10), and the femoral component 90 by the table 20. Pressing the outer surface 98 (FIG. 11) and hooking the pair of hooks 16 to the left and right edges 92 of the inner surface 96 of the femoral component 90 (FIG. 10), the lever 30 in the starting position (FIG. 9). To the end position (FIG. 12).
Moreover, since a series of operation of FIGS. 9-12 can be performed by holding | griping the cylinder 40 and the lever 30 simultaneously, it can be operated with one hand. Therefore, the femoral component 90 is supported with the other hand, and it is easy to finely adjust the hook 16 of the arm 10 so as to be surely engaged with the recess 95 of the femoral component 90.

When the holding device 1 is used for surgery, the free end 33 of the lever 30 can be prevented from moving away from the cylinder 40 by simultaneously holding the lever 30 and the cylinder 40 in the state shown in FIG. Thus, the femoral component 90 can be prevented from falling off while the femoral component 90 is driven into the distal femoral portion 102.
Further, from the state of holding the femoral component to Okiagara the lever 30 (i.e., the free end 33 of the lever 30 in the direction of R ₂ in FIG. 4 by rotational movement, away from the cylinder 40) by the arm 10 and table 20 can simultaneously leave the femoral component and the femoral component 90 can be easily released from the holding device 1.

  Further, in the conventional holding device 1001 as shown in FIG. 23, the proximal side of the table dial 1028 is hit when the femoral component 90 is driven. However, in the present embodiment, since the top plate 80 for driving can be provided, it can be formed into a shape that can be easily hit with a hammer. Furthermore, by designing the size and shape of the top plate 80 so that the distal surface of the top plate 80 can be hit with a hammer, it is easy to remove the simulated femoral component 90.

  It is desirable to use medical instrument materials that can all be sterilized as components of the holding instrument 1. In particular, the buffer pad 24 is preferably formed from a sterilizable resin or rubber, and the other components are preferably formed from a metal material.

<Embodiment 2>
In the femoral component holding device 1 according to the present embodiment, as shown particularly in FIGS. 13 to 16, the lever 30 includes a lever side uneven portion 39 on the inner surface 37 facing the cylinder 40. The slide pipe 60 includes a slide pipe side uneven portion 69 that meshes with the lever side uneven portion 39 on a surface 67 facing the lever 30.
And in the holding fixture 1 of this Embodiment, as shown especially in FIGS. 18-19, the adjustment screw 28 for adjusting the position of the longitudinal direction of the table 20 and the shaft 50 to the cylinder 40 side of the table 20 is shown. Is fixed.
Furthermore, in the holding device 1 of the present embodiment, as shown in FIGS. 20 to 21 in particular, the shape of the arm 10 (mainly the tip portion) is changed compared to the first embodiment.
Other than the above, the second embodiment is the same as the first embodiment.

Below, the characteristic part different from Embodiment 1 among the holding devices 1 for femoral components of this Embodiment is explained in full detail.
As shown in FIGS. 13 to 16, a lever side uneven portion 39 having a triangular section is formed on the inner surface 37 of the lever 30 of the holding device 1, and a slide pipe having a triangular section is formed on the surface 67 of the slide pipe 60. Side uneven portions 69 are formed.

  When the lever 30 is tilted toward the cylinder 40 as shown in FIG. 15A, the lever side uneven portion 39 approaches the slide pipe side uneven portion 69 as shown in FIG. 15B. However, since the lever 30 has not yet reached the final position, there is a gap between the lever side uneven portion 39 and the slide pipe side uneven portion 69. At this time, the slide pipe 60 is in a state of being biased by the spring 70 in the distal direction. That is, the slide pipe 60 can slide in the proximal direction when a force is applied against the spring 70. This means that the arm 10 opens.

Further the free end 33 of the lever rotates and moves in the _{R 1} direction (further defeat lever 30), as shown in FIG. 16 (A), the lever 30 is moved to the final position, as in FIG. 16 (B), The lever side uneven portion 39 and the slide pipe side uneven portion 69 mesh with each other, and the slide pipe 60 and the cylinder 40 are fixed. When the slide pipe 60 is fixed, the arm 10 is also fixed and the arm 10 does not open. Therefore, when the femoral component 90 is driven in or removed, there is no possibility that the fixation of the femoral component 90 is loosened.

  The lever side uneven portion 39 is formed at a position where it engages with the slide pipe side uneven portion 69, and is preferably formed near the free end 33 of the lever 30. Thereby, the lever-side uneven portion 39 and the slide pipe-side uneven portion 69 are unlikely to mesh with each other until the lever 30 moves to the final position. That is, there is an effect that the slide pipe can be prevented from being fixed at an undesired position while the lever is being tilted.

The position of the slide pipe 60 in the far proximal direction varies slightly depending on the size of the femoral component 90 used. Therefore, it is preferable to form the lever side uneven portion 39 long in the far proximal direction so as to surely engage with the slide pipe side uneven portion 69.
It is preferable to set the pitch between the slide-side uneven portion 69 and the lever-side uneven portion 39 to 1 mm to 3 mm because it can cope with variations in the dimensions of the femoral component 90.

In FIG. 13 to FIG. 16, the slide pipe side uneven portion 69 and the lever side uneven portion 39 are formed in a triangular shape, but the present invention is not limited to this, and the slide pipe side uneven portion 69 and the lever side uneven portion 39 are formed. Any shape that engages can be applied.
Further, it is preferable that the heights of the slide pipe side uneven portion 69 and the lever side uneven portion 39 are 0.5 mm or more because the slide pipe side uneven portion 69 and the lever side uneven portion 39 are firmly engaged with each other. In particular, when the height is set to 0.5 mm to 2 mm, the slide pipe side uneven portion 69 and the lever side uneven portion 39 are unlikely to contact each other and the lever 30 moves to the end position until the lever 30 moves to the end position. In this case, the slide pipe side uneven portion 69 and the lever side uneven portion 39 are sufficiently engaged with each other, which is preferable.

In the holding device 1 of the present embodiment, as shown in FIGS. 15A and 16A, an adjustment screw 28 is fixed to the cylinder 40 side of the table 20.
As shown in FIG. 17, the adjustment screw 28 has a screw hole 283 in which a female screw is formed, and a plurality of adjustment holes 282 in a surface 281 facing the cylinder 40. In addition, if an anti-slip 283 is formed around the adjustment screw 28, it is convenient to rotate the adjustment screw 28 by hand.

  As shown in FIG. 18, the adjustment screw 28 is rotatably fixed to the cylinder 40 side of the table 20, and a male screw formed at the distal end of the shaft 50 is screwed into the screw hole 283 of the adjustment screw 28. ing. That is, the table 20 is fixed to the shaft 50 via the adjustment screw 28. When the adjustment screw 28 is rotated, the adjustment screw 28 and the table 20 move along the far proximal direction (the long axis direction of the shaft 50) with respect to the shaft 50.

When actually performing a replacement operation of the femoral component 90, there is a problem in that the strength of fixing is increased or decreased when the femoral component 90 is fixed with the same holding device 1 due to a slight variation in the size of the femoral component for each individual product. For example, when fixing the thin femoral component 90, even if the lever 30 is fully lowered to the final position, the pressing of the femoral component 90 by the table 20 is not sufficient, and the fixing force of the femoral component 90 is weak. There is a fear. Further, when fixing the thick femoral component 90, before the lever 30 is fully lowered to the final position, the pressing of the femoral component 90 by the table 20 becomes too strong and the lever 30 is lowered to the end position. There is a risk that it will not be possible.
In order to solve these problems, the position of the table 20 in the long axis direction of the shaft 50 is preferably adjusted. In the present embodiment, since the adjusting screw 28 can be rotated by hand, the position of the table 20 can be easily adjusted even during surgery.

More preferably, as shown in FIGS. 18 and 19, a shaft step 58 formed on the proximal side of the shaft 50 and a cylinder step 48 formed on the proximal side in the shaft insertion hole 46 of the cylinder 40 are provided. By disposing the spring 72, the table 20 fixed to the distal end of the shaft 50 is spring-biased toward the cylinder 40 (proximal direction).
As shown in FIG. 19, the proximal end of the cylinder 40 is provided with a protrusion 49 that protrudes toward the adjustment screw 28. The protrusion 49 is disposed at a position corresponding to the adjustment hole 282 (see FIG. 17) of the adjustment screw 28.

  In the case of the holding device 1 in which the table 20 is spring-biased and the cylinder 40 is provided with the protrusion 49, the protrusion 49 is inserted into the adjustment hole 282 of the adjustment screw 28 in the state of FIG. 28 cannot be rotated. Therefore, the table 20 is pulled in the distal direction (the direction of the arrow in FIG. 18) to release the adjustment screw 28 from the protrusion 49 (FIG. 19). In this state, the adjusting screw 28 can be rotated. When the table 20 is released after the adjustment of the position of the table 20 is finished, the table 20 is pulled back to the cylinder 40 side (proximal direction) by the spring 72. At this time, the protrusion 49 is inserted into the adjustment hole 282 and the adjustment screw 28 is fixed. That is, the holding device 1 of the present embodiment can not only easily adjust the position of the table 20 but also adjust the position of the table 20 by simply pulling the table 20, rotating the adjusting screw 28, and releasing the table 20. Then, the adjustment screw 28 can be prevented from rotating carelessly.

The number of adjustment holes 282 formed in the adjustment screw 28 can be arbitrarily determined, but is usually determined in consideration of the adjustment pitch of the table 20. For example, when the pitch of the female screw formed in the screw hole 283 is 1.2 mm and the adjustment pitch is set to 0.15 mm, the number of the adjustment holes 282 is determined as 1.2 / 0.15 = 8. it can.
Further, the number of the protrusions 49 can be one or plural.

The arm 10 used in the holding device 1 of the present embodiment has a tip that is thinner than that of the first embodiment. Further, at the time of surgery, the distal end region 10X (hatched portion) of the arm 10 enters the body, but the outer arm 10 is not extended so as to protrude greatly inward in the distal end region 10X. It is designed not to overhang outward. Thereby, the maximum width W1 of the tip region 10X of the arm 10 of the present embodiment (FIG. 21A) is larger than the maximum width W2 of the tip region 10X of the arm 10 of the first embodiment (FIG. 21B). Can also be narrowed. Therefore, it is suitable for the minimally invasive technique (MIS) procedure.
Further, when the rod guide 14 provided in the arm 10 is lengthened, the function of guiding the rod 44 that slides in the rod guide 14 is enhanced, and the sliding of the rod 44, that is, the opening / closing operation of the arm 10 becomes smooth. There are advantages.

1 is a perspective view of a femoral component holding device according to Embodiment 1. FIG. FIG. 6 is a perspective view showing a usage state of the femoral component holding device according to the first embodiment. FIG. 3 is a perspective view of a cylinder and a lever of the femoral component holding device according to the first embodiment, showing a state where the lever is raised. It is a perspective view of the cylinder and lever which are used for the femoral component holding device concerning Embodiment 1, and shows the state where the lever fell. It is a perspective view of the shaft, table, and top plate used for the femoral component holding device according to the first embodiment. 3 is a partially cutaway perspective view of a slide pipe used in the femoral component holding device according to Embodiment 1. FIG. 3 is a perspective view of a pair of arms used in the femoral component holding device according to Embodiment 1. FIG. FIG. 3 is a perspective view of a spring used in the femoral component holding device according to the first embodiment. 6 is a partial cross-sectional perspective view for explaining the operation of the femoral component holding device according to Embodiment 1. FIG. 6 is a partial cross-sectional perspective view for explaining the operation of the femoral component holding device according to Embodiment 1. FIG. 6 is a partial cross-sectional perspective view for explaining the operation of the femoral component holding device according to Embodiment 1. FIG. 6 is a partial cross-sectional perspective view for explaining the operation of the femoral component holding device according to Embodiment 1. FIG. FIG. 6 is a perspective view of a femoral component holding device according to a second embodiment. FIG. 6 is a partially cutaway perspective view of a slide pipe used for a femoral component holding device according to a second embodiment. It is a side view of the holding device for femoral components which concerns on Embodiment 2 (A, B). It is a side view of the holding device for femoral components which concerns on Embodiment 2, and has shown the state which the lever moved to the end position (A, B). FIG. 10 is a perspective view of an adjustment screw used in a femoral component holding device according to a second embodiment. 10 is a partial cross-sectional front view for explaining the operation of the femoral component holding device according to Embodiment 2. FIG. 10 is a partial cross-sectional front view for explaining the operation of the femoral component holding device according to Embodiment 2. FIG. 6 is a perspective view of a pair of arms used in a femoral component holding device according to Embodiment 2. FIG. (A) is a partial front view of the femoral component holding device according to the second embodiment, and (B) is a partial front view of the femoral component holding device according to the first embodiment. It is a perspective view of the conventional holding device for femoral components. It is a perspective view explaining the surgical technique using the conventional holding device for femoral components.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Holding device for femoral components 10 Arm 16 Hook 20 Table 28 Adjustment screw 282 Adjustment hole 30 Lever 32 Connection plate 39 Lever side uneven part 40 Cylinder 42 Cylinder penetration long hole 49 Projection part 50 Shaft 52 Shaft penetration long hole 60 Slide Pipe 642 Slide-through long hole 68 Step difference 69 Slide pipe side uneven part 70 Spring 80 Top plate 90 Femoral component 96 Inner surface of femoral component 98 Outer surface of femoral component

Claims (7)

A holding device for holding a curved femoral component for a knee prosthesis having an outer surface having a right condyle and a left condyle and an inner surface opposite to the outer surface,
A pair of arms each having a hook and sandwiching the femoral component from the left and right;
A table positioned between the pair of arms;
A lever having a free end and a fixed end and interlocking with the arm and the table;
A cylinder in which the fixed end of the lever is rotatably supported;
A slide pipe coupled to the pair of arms and having the cylinder slidably inserted therein;
A pair of connection plates that connect the lever and the slide pipe ;
One end of the connection plate is rotatably supported between the fixed end and the free end of the lever, and the other end is held movably on the slide pipe,
The pair of pipes coupled to the slide pipe by sliding the slide pipe along the cylinder through the connection plate by tilting the lever in the direction of the cylinder around the fixed end of the lever. The arms of each other
The femoral component is clamped from the left and right by the pair of arms, the outer surface of the femoral component is pressed by the table, and the pair of hooks are hooked on the left and right edges of the inner surface of the femoral component. This is performed while the lever is moved from the start position to the end position where the lever is tilted toward the cylinder . The holding device further has a slidably inserted through shafts bets the table is fixed to one end before Symbol cylinder,
Before Symbol shaft is connected to the lever by the connecting plate,
Wherein the other end of the connection plate is movably held by the shafts bets,
By defeating the lever in the direction of the cylinder, the holding device of claim 1 through the connection plate, characterized in that it slides along the shafts bets on the cylinder. A slide pin that moves in the direction of the table is coupled to the other end of the connection plate,
The shaft has a hole through which the slide pin is inserted,
The slide pipe is disposed closer to the table than the slide pin,
A spring is disposed between the slide pipe and the slide pin and around the cylinder;
By tilting the lever in the direction of the cylinder, the shaft is slid in the direction of the table via the slide pin, and the slide pipe is slid in the direction of the table via the slide pin and the spring. The holding device according to claim 2 , wherein the holding device is moved. The cylinder side of the table, holding according to any one of claims 2 or 3 adjusting screw for adjusting the longitudinal position of the said table shaft, characterized in that it is fixed Instruments. The adjustment screw has a plurality of adjustment holes formed on a surface facing the cylinder,
The cylinder has a protrusion at a position corresponding to the adjustment hole,
Another spring is disposed between the step formed in the shaft and the step formed in the insertion hole of the cylinder through which the shaft is inserted,
The table is spring-biased in the cylinder direction by the another spring, and after adjusting the position of the table by rotating the adjustment screw, the table moves to the cylinder side to the adjustment hole. The holding device according to claim 4 , wherein the protrusion is inserted. Said lever has a lever-side irregular portion on the inner surface facing the cylinder,
The slide pipe has a slide pipe side uneven portion that meshes with the lever side uneven portion on a surface facing the lever,
6. The slide pipe and the cylinder are fixed by engaging the lever side uneven portion and the slide pipe side uneven portion when the lever is moved to the end position . The holding device according to any one of claims. The holding device according to any one of claims 1 to 6 , wherein the femoral component is hooked by the hook before being pressed by the table.

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