Surgical instrument

Abstract

A surgical instrument that can reduce the difficulty of surgery for vertebral bodies, the surgical instrument comprising: a first member (10) that has a pair of first surfaces (11, 11) parallel to each other and extending along the first direction, and a pair of second surfaces (12, 12) parallel to each other and intersecting the pair of first surfaces (11, 11); and a second member (20) that has a groove portion (20h) for accommodating the first member (10), wherein the groove portion (20h) of the second member (20) has a bottom wall (21) extending along the axial direction of the groove portion (20h), and a pair of side walls (22, 22) parallel to each other and extending along the axial direction of the groove portion (20h); and in the second member (20), the distance between the inner surfaces of the pair of side walls (22, 22) is formed to a length such that the first member (10) and the second member (20) can move relative to each other along the axial direction of the groove portion (20h) in a state where the first direction of the first member (10) and the axial direction of the groove portion (20h) of the second member (20) are set parallel to each other.

Description

Technical Field

[0001] The present invention relates to a surgical instrument. More specifically, the present invention relates to a surgical instrument used in surgeries such as placing an implant between vertebral bodies constituting the spine to fix the interval of the intervertebral space and performing procedures within joints.

Background Art

[0002] The human spine is formed from a plurality of bones called vertebrae. In the spine, the vertebral bodies of the vertebrae arranged from the head to the buttocks are connected via intervertebral discs and joints, and the vertebral arches of the vertebrae arranged vertically are connected by facet joints and ligaments to form the spine (see FIG. 11).

[0003] In such a spinal column, there are diseases such as spondylosis, spondylolisthesis, spinal instability, spinal stenosis, intervertebral disc degeneration, intervertebral disc herniation, and degenerative disc herniation. In diseases due to aging or in athletes, etc., the intervertebral space between vertebral bodies becomes narrower due to degeneration of the intervertebral disc. When the intervertebral space between vertebral bodies becomes narrower, for example, degenerative joint disease changes in the posterior joints may occur, leading to chronic pain, or herniation may occur. In order to return such a state where the intervertebral space between vertebral bodies has become narrower to a normal state, that is, the state before the intervertebral space between vertebral bodies becomes narrower, an implant is placed between the vertebral bodies of the vertebrae.

[0004] Conventionally, when placing an implant between the vertebral bodies of the vertebrae, an invasive surgical operation was performed in which the patient's back was incised to expose the spine and the implant was placed. However, in recent years, in order to reduce the burden on the patient, a surgery for placing an implant between the vertebral bodies of the vertebrae by a less invasive surgery has been performed, and instruments used in that surgery have also been developed (see Patent Document 1).

[0005] Patent Document 1 discloses an expandable introducer for spinal surgery. This expandable introducer for spinal surgery is capable of expanding the space between vertebral bodies by inserting the tip of an expander tube between the vertebral bodies of the spine. Then, by inserting instruments or implants through the space inside the expander tube, operations can be performed in the expanded space between vertebral bodies and implants can be installed between vertebral bodies.

[0006] However, since the cross-section of the expander tube in Patent Document 1 is circular, the size of instruments or implants that can pass through the space inside the expander tube is limited. Moreover, in the case of instruments or implants with a non-circular cross-section, only those with a significantly smaller cross-sectional area compared to the cross-sectional area of the expander tube can be used. For example, although implants with a rectangular (elongated rectangular) cross-section are used, if an attempt is made to ensure a certain thickness (the length of the shorter side) of the implant, only those with a long side significantly smaller than the inner diameter of the expander tube can pass through the inside of the expander tube. Therefore, with the expander tube in Patent Document 1, the types of surgeries that can be performed and the size of implants that can be installed are severely restricted.

[0007] On the other hand, as a dilator tube (sleeve) to be inserted between the vertebral bodies of the vertebrae, a tube with a substantially rectangular cross-section has also been developed (Patent Document 2). The tube in Patent Document 2 is for inserting an implant with a substantially rectangular cross-section between vertebral bodies, and the shape of its internal space is formed to be approximately similar to the cross-section of the implant to be inserted. Therefore, an implant with a substantially rectangular cross-section having a size equivalent to the cross-sectional area of the tube can be stably installed between vertebral bodies.

[0008] However, in the tube of Patent Document 2, when the tube is inserted between vertebral bodies, although the space between the vertebral bodies can be widened by the length of the short side of the tube, if the implant placed between the vertebral bodies is thick, the thickness of the tube itself has to be increased, or it will come apart. Then, in patients with a narrow space between the vertebral bodies, the difference between the thickness of the tube and the space between the vertebral bodies becomes large, so a great deal of effort is required to insert the tube, and the burden on the patient also increases. And in some cases, it may be difficult for some patients to insert such a thick tube. That is to say, the tube of Patent Document 2 has limited applicable situations.

[0009] On the other hand, as a tube to be inserted between the vertebral bodies of vertebrae, a tube with an elliptical cross-section has also been developed (Non-Patent Document 1). By using a tube with such a shape, even for an implant with a certain thickness (the length in the short-axis direction of the tube) and a long long side (the length in the long-axis direction of the tube) compared to a tube with a circular cross-section, it can be placed between the vertebral bodies through the space inside the tube.

[0010] Moreover, in Non-Patent Document 1, it is described that if the tube is inserted between the vertebral bodies with the short-axis direction of the tube parallel to the direction in which the vertebral bodies are arranged, and the tube is rotated from the state of being inserted between the vertebral bodies (if the direction in which the vertebral bodies are arranged is made parallel to the long-axis direction of the tube), the space between the vertebral bodies can be widened compared to the state where the tube is inserted. Then, while reducing the burden of inserting the tube between the vertebral bodies, etc., the space between the vertebral bodies can be made wider than the length of the short axis of the tube, so the operation between the vertebral bodies becomes easier and the installation of the implant also becomes easier.

Prior Art Documents

Patent Documents

[0011]

Patent Document 1

Patent Document 2

Non-Patent Documents

[0012] [Non-Patent Document 1] Kenji Nagahama, "Percutaneous Endoscopic Lumbar Interbody Fusion: PETLIF (Petrif)", Spine and Spinal Cord, Vol. 32, No. 9, pp. 843-849, Maruzen Bookstore, September 25, 2019 [Summary of the Invention] [Problems to be Solved by the Invention]

[0013] However, in the case of the tube of Non-Patent Document 1, when the direction in which the vertebral bodies are arranged is parallel to the long axis direction (hereinafter referred to as the expanded state), a force is applied to the tube along the long axis direction from the vertebral body. Then, when the direction of the force and the long axis direction do not completely coincide, a force to return the tube to its original state is applied. Therefore, in order to maintain the posture of the tube in the expanded state, it is necessary to hold the rotation of the tube, so an instrument or an operator for holding the rotation is required, which may increase the difficulty of the procedure.

[0014] In view of such circumstances, an object of the present invention is to provide a surgical instrument that can reduce the difficulty of surgery between vertebral bodies. [Means for Solving the Problems]

[0015] The surgical instrument of the first invention is an instrument used for surgery between vertebrae of the spine, and includes a first member having a pair of first surfaces parallel to each other extending along a first direction, and a pair of second surfaces parallel to each other intersecting the pair of first surfaces extending along the first direction, and a second member having a groove portion for accommodating the first member communicating between a first end portion and a second end portion, wherein the groove portion of the second member has a bottom wall extending along the axial direction of the groove portion, and a pair of side walls parallel to each other extending along the axial direction of the groove portion, and the second member is formed to have a length such that the distance between the inner surfaces of the pair of side walls allows the first member and the second member to be relatively movable along the axial direction of the groove portion with the first direction of the first member and the axial direction of the groove portion of the second member being parallel. [Effects of the Invention]

[0016] According to the first invention, if the first end portion of the first member in the first direction is inserted between the vertebral bodies such that a pair of first surfaces face the vertebral bodies, the distance between the vertebral bodies can be increased. Then, with the first member accommodated in the groove portion, if the second member is moved along the first member, the first end portion of the second member can be disposed between the vertebral bodies. Thereafter, if the first member is removed from the second member, a route communicated between the vertebral bodies can be formed by the groove portion.

Brief Description of the Drawings

[0017]

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Mode for Carrying Out the Invention

[0018] The surgical instrument of the present embodiment relates to a surgical instrument used for surgeries such as placing an implant between vertebral bodies constituting the spine to fix the interval between vertebral bodies and for foraminal enlargement.

[0019] The surgeries and procedures in which the surgical instrument of the present embodiment is used are not particularly limited, and any surgery or procedure in which a treatment between vertebral bodies is performed can be adopted. For example, during surgeries such as posterior lumbar interbody fusion (PLIF) / transforaminal lumbar interbody fusion (TLIF), oblique lateral interbody fusion (OLIF), extreme lateral interbody fusion (XLIF), anterior lumbar interbody fusion (ALIF), etc., it can be used to maintain the space between vertebral bodies or to insert a surgical instrument or bone to be transplanted between vertebral bodies. Also, the surgical instrument of the present invention can be used when collecting tissues, etc. from the spine.

[0020] In the following example, the case of inserting the surgical instrument of the present embodiment between vertebral bodies through Kambin's triangle (TR: Safety triangle, see FIGS. 11 and 12) will be described. However, the position where the surgical instrument of the present embodiment is inserted between vertebral bodies is not limited to Kambin's triangle. For example, the surgical instrument of the present invention may be inserted between vertebral bodies from the lateral side or the posterior side of the vertebra. Note that the two-dimensional planar Kambin's triangle TR is a triangle with the bottom side being the upper endplate of the lower vertebral body, the height being the intervertebral foramen side of the superior articular process, and the upper exiting nerve root (hereinafter sometimes simply referred to as the nerve) being the hypotenuse.

[0021] <The surgical instrument 1 of the present embodiment> As shown in FIGS. 1 and 2, the surgical instrument 1 of the present embodiment includes a first member 10, a second member 20, and a guide member 30. The first member 10 is an instrument used to widen the gap between the vertebral bodies VB of the vertebra V of the spine C. The second member 20 is an instrument used to communicate between the space between the vertebral bodies VB of the spine C and the outside and secure a path for the surgeon to access between the vertebral bodies VB. The guide member 30 is an instrument used to guide the movement of the first member 10 when the first member 10 is introduced between the vertebral bodies VB of the vertebra V of the spine C. Hereinafter, each instrument will be described with reference to the drawings.

[0022] Note that the guide member 30 is not necessarily required for the operation between the vertebral bodies VB described later. However, in order to perform the procedure easily and accurately, it is desirable to use the guide member 30 when inserting the first member 10 and the second member 20 between the vertebral bodies VB. That is, in order to accurately and quickly insert the first member 10 between the vertebral bodies VB of the vertebra V of the spine C, it is desirable to use the guide member 30.

[0023] <The first member 10> As shown in FIGS. 1 and 2(B), the first member 10 is a rod-shaped member extending along the axial direction (the first direction as referred to in the claims). The first member 10 has a pair of first surfaces 11, 11 that are parallel to the axial direction and parallel to each other. The pair of first surfaces 11, 11 are formed as flat planes. Further, the first member 10 has a pair of second surfaces 12, 12 that are parallel to the axial direction and parallel to each other. Moreover, the pair of second surfaces 12, 12 are provided so as to be orthogonal to the pair of first surfaces 11, 11. That is, the cross-section of the first member 10 orthogonal to its axial direction is formed in a substantially rectangular shape with the pair of first surfaces 11, 11 as the long sides and the pair of second surfaces 12, 12 as the short sides.

[0024] The distance W1 between the pair of second surfaces 12, 12 is longer than the distance T1 between the pair of first surfaces 11, 11 (in other words, the distance T1 between the pair of first surfaces 11, 11 is shorter than the distance W1 between the pair of second surfaces 12, 12). The difference between the distance W1 and the distance T1 may be appropriately adjusted according to the patient and the surgery for which the surgical instrument 1 of the present embodiment is used, and is not particularly limited. For example, in the case of using it for an intervertebral fixation surgery, it is desirable that the difference between the distance W1 and the distance T1 be as small as possible (about 1 to 3 mm). As will be described later, when forming a space larger than the distance T1 between the pair of first surfaces 11, 11 between the vertebrae VB, a plurality of first members 10 having different sizes of the distance W1 and the distance T1 may be used. That is, it is preferable to insert the first members 10 with smaller sizes of the distance W1 and the distance T1 between the vertebrae VB and gradually expand the space between the vertebrae VB.

[0025] Further, for the first member 10, the end face of the first end portion 10a in its axial direction (the end portion located on the left side in FIGS. 1 and 2) is formed as a flat surface orthogonal to the pair of first surfaces 11, 11 and / or the pair of second surfaces 12, 12. Moreover, a pair of inclined surfaces 11f, 11f are formed on the first end portion 10a. The pair of inclined surfaces 11f, 11f are formed such that the distance therebetween becomes shorter as they approach the end face of the first end portion 10a. In other words, the pair of inclined surfaces 11f, 11f are formed to incline toward the other first surface 11 as they approach the end face of the first end portion 10a.

[0026] And, a through hole 10h penetrating the end face of the first end portion 10a and the end face of the second end portion 10b (the end portion located on the right side in FIGS. 1 and 2) is formed in the first member 10. The through hole 10h is formed parallel to the axial direction of the first member 10 (see FIG. 1(C)). The through hole 10h communicates with a recess 10d formed in the end face of the first end portion 10a for accommodating a stopper 32 of a guide member 30 described later (see FIG. 1(B)). The recess 10d is a substantially hemispherical recess having a radius of curvature larger than the radius of the through hole 10h, and is formed in a size capable of accommodating the stopper 32 of the guide member 30.

[0027] <Second member 20> As shown in FIGS. 1 and 2(C), the second member 20 is a gutter-shaped member having a groove portion 20h extending along the axial direction. Specifically, the second member 20 includes a flat bottom wall 21 extending along the axial direction, and a pair of flat side walls 22, 22 extending along the axial direction provided on both sides of the bottom wall 21. One end edge of the pair of side walls 22, 22 (the lower end edge in FIGS. 1(B) and (C)) is connected to the side edge of the bottom wall 21. And the pair of side walls 22, 22 are provided parallel to each other and with their inner surfaces substantially orthogonal to the inner surface of the bottom wall 21. That is, the second member 20 has a groove portion 20h extending along the axial direction surrounded by the bottom wall 21 and the pair of side walls 22, 22. Note that the outer surfaces of the pair of side walls 22, 22 are also formed as flat surfaces, and the pair of side walls 22, 22 are formed as surfaces parallel to each other.

[0028] The groove portion 20h of the second member 20 is open between the edges located on the side opposite to the bottom wall 21 in the pair of side walls 22, 22 (the upper edges in FIGS. 1(B) and 1(C), which may be hereinafter referred to as upper edges). Further, the second member 20 has openings of the groove portion 20h formed at its first end portion 20a (the end portion located on the left side in FIGS. 1 and 2) and second end portion 20b (the end portion located on the right side in FIGS. 1 and 2). That is, the groove portion 20h of the second member 20 is a groove with an open upper portion that communicates between the first end portion 20a and the second end portion 20b.

[0029] The groove portion 20h of the second member 20 is formed to have a size capable of accommodating the above-described first member 10 (see FIG. 1). Moreover, when the first member 10 is accommodated in the groove portion 20h such that the axial direction of the groove portion 20h is parallel to the axial direction of the first member 10, the first member 10 and the second member 20 are formed to be relatively movable (slidable) along the axial direction of the groove portion 20h. Specifically, the distance W2 between the inner surfaces of the pair of side walls 22, 22 is the same as (the state where the inner surfaces of the pair of side walls 22, 22 and the pair of second surfaces 12, 12 of the first member 10 are in surface contact) or slightly longer than the distance W1 between the surfaces of the pair of second surfaces 12, 12 of the first member 10 (see FIGS. 1(B) and 1(C)). For example, the difference between the distance W1 and the distance W2 is formed to be 1 mm or less. Then, even when the first member 10 and the second member 20 are relatively moved, they can be moved while maintaining their axial directions substantially parallel.

[0030] Note that the height T2 (the length from the inner surface of the bottom wall 21 to the upper edge of the side wall 22) of the pair of side walls 22, 22 of the groove portion 20h of the second member 20 is not particularly limited. It may be the same as the distance T1 between the surfaces of the pair of first surfaces 11, 11 of the first member 10, or may be shorter or longer than the distance T1. As will be described later, when the first end portion 20a of the second member 20 is inserted between the vertebral bodies VB with the first end portion 10a of the first member 10 disposed between the vertebral bodies VB, it is desirable that the distance T2 be equal to or slightly longer than the distance T1.

[0031] A flange portion 25 that is held when the second member 20 is moved is provided at the second end portion 20b of the second member 20. This flange portion 25 also has a function of restricting the movement of the second member 20. When the end face of this flange portion 25 is disposed at a predetermined position of the second end portion 10b of the first member 10, the end face of the first end portion 10a of the first member 10 protrudes from the end face of the first end portion 20a of the second member 20 by a predetermined length (see Fig. 1(A)). Note that if the second member 20 can be operated and positioned even without the flange portion 25, the flange portion 25 is not necessarily provided.

[0032] <Guide member 30> As shown in Figs. 1 and 2(A), the guide member 30 has a wire portion 31 and a stopper 32 provided at the tip of the wire portion 31.

[0033] The wire portion 31 is formed of a material having a certain degree of flexibility and high tensile strength. For example, a known guide wire used in posterior spinal surgery or fracture treatment using percutaneous pedicle screws (PPS) can be used as the wire portion 31. This wire portion 31 is inserted into the through hole 10h of the first member 10 described above, and its diameter is smaller than the diameter of the through hole 10h of the first member 10.

[0034] The stopper 32 is provided at the tip (first end portion) of the wire portion 31. This stopper 32 is a sphere formed of, for example, a material equivalent to that of the wire portion 31. This stopper 32 is a sphere, and its diameter is formed larger than the diameter of the wire portion 31 and the diameter of the through hole 10h. This stopper 32 is provided so that the first member 10 does not fall off from the tip of the wire portion 31 when the rear end of the wire portion 31 is inserted into the through hole 10h of the first member 10 from the first end portion 10a. In other words, the stopper 32 is provided so that the first end portion 10a of the first member 10 does not move ahead of the stopper 32 even when the first member 10 is moved along the wire portion 31.

[0035] In addition, it is desirable that the sphere forming the stopper 32 is formed such that its radius is substantially the same as the radius of curvature of the recess 10d of the first member 10. Also, the stopper 32 is not limited to a sphere, but if it is a sphere, when inserting the wire portion 31 of the guide member 30 into the triangle TR of the cambium, it is possible to prevent damage to blood vessels, nerves, etc. by the tip of the wire portion 31.

[0036] <Surgical example using the surgical instrument 1 of the present embodiment> Hereinafter, with reference to the drawings, a case of performing a surgery for placing an implant IP between vertebral bodies VB using the surgical instrument 1 of the present embodiment will be described. In the following description, it is assumed that the procedure is performed while confirming the position of the surgical instrument 1 of the present embodiment in the patient's body under fluoroscopy.

[0037] In addition, in the surgery, in addition to the first member 10, the second member 20, and the guide member 30 described above, cases where a shaver 40 (see Fig. 13(A)), an implant insertion instrument 45 (see Fig. 13(B)), an instrument for performing a procedure between vertebral bodies VB, etc. are used are also described. For these shavers 40, implant insertion instruments 45, and other instruments, commercially available known instruments can be used. These shavers 40, implant insertion instruments 45, and other instruments may also be included in the surgical instrument 1 of the present embodiment.

[0038] In the drawings, in order to make the relationship between the surgical instrument 1 of the present embodiment and the vertebral body VB during surgery easy to understand, tissues such as the patient's muscles existing around the spine C are omitted. Also, Figs. 6 to 10 show the interference state between the surgical instrument 1 of the present embodiment and the vertebra VB, and thus the surgical instrument 1 of the present embodiment and the vertebra VB, etc. are described. However, in Figs. 3 to 5 and Fig. 14, only the surgical instrument 1 of the present embodiment is described in order to make the relevance of each instrument easy to understand.

[0039] Also, the following procedures are described on the premise that they are performed while confirming the relative positions of each instrument and the vertebra VB by fluoroscopic images. When fluoroscopic images are not used, the relative positions of each instrument and the vertebra VB are to be confirmed using an endoscope or the like.

[0040] First, a hole (hereinafter simply referred to as an introduction hole) for inserting the surgical instrument 1 of the present embodiment is formed in the back of the patient on whom the procedure is to be performed. The position where the introduction hole is formed varies depending on the patient, but when the surgical instrument 1 of the present embodiment is inserted into the introduction hole, through the triangle TR of the cambine (see FIGS. 10 and 11), it is formed at a position where the tip of the guide member 30, the first end portion 10a of the first member 10, and the first end portion 20a of the second member 20 can be inserted between the vertebral bodies VB.

[0041] When the introduction hole is formed in the back, first, the guide member 30 is inserted through the introduction hole and through the triangle TR of the cambine into the intervertebral disc between the vertebral bodies VB (see FIGS. 3(A) and 6(A)). Note that the proximal end of the wire portion 31 of the guide member 30 is positioned outside the patient's body through the introduction hole.

[0042] When the wire portion 31 of the guide member 30 is arranged, the first member 10 is inserted from the rear end of the wire portion 31. Specifically, the wire portion 31 is inserted into the through hole 10h from the end face of the first end portion 10a of the first member 10 (see Fig. 3(B)). Then, the first member 10 is moved along the wire portion 31 (see Fig. 6(B)). Then, the first end portion 10a of the first member 10 is inserted into the intervertebral disc between the adjacent vertebral bodies VB (see Fig. 4(A) and Fig. 7(A)). At this time, the first member 10 maintains its posture such that its pair of first surfaces 11, 11 intersect the direction in which the vertebral bodies V are arranged. That is, the first end portion 10a of the first member 10 is inserted into the intervertebral disc between the adjacent vertebral bodies VB in a posture such that its pair of first surfaces 11, 11 respectively contact the opposing surfaces of the vertebral body VB (see Fig. 7(A)). Then, if the gap between the adjacent vertebral bodies VB is narrower than the distance between the pair of first surfaces 11, 11 of the first member 10, the gap between the adjacent vertebral bodies VB will be widened to the distance T1 between the pair of first surfaces 11, 11. At this time, if a pair of inclined surfaces 11f, 11f are provided at the first end portion 10a of the first member 10, the first end portion 10a of the first member 10 can be inserted between the vertebral bodies VB with a relatively small force. Note that even when the first end portion 10a is inserted between the vertebral bodies VB, the second end portion 10b of the first member 10 is exposed outside the patient's body.

[0043] When the first end portion 10a of the first member 10 is inserted into the intervertebral disc between the adjacent vertebral bodies VB, the first member 10 is rotated around the wire portion 31 to widen the gap between the adjacent vertebral bodies VB (see FIGS. 4(A) and 7(A)). Specifically, a handle 50 is attached to the second end portion 10b of the first member 10 (see FIGS. 4(A) and (B)), and the first member 10 is rotated until the pair of second surfaces 12, 12 of the first member 10 come into contact with the opposing surfaces of the vertebral bodies VB respectively (until rotated by 90 degrees) (see FIGS. 4(B) and 7(B)). Then, since the distance W1 between the pair of second surfaces 12, 12 is longer than the distance T1 between the pair of first surfaces 11, 11 of the first member 10, the gap between the adjacent vertebral bodies VB is widened compared to when the first end portion 10a of the first member 10 was inserted. That is, the gap between the adjacent vertebral bodies VB is widened up to the distance W1 between the pair of second surfaces 12, 12. Moreover, since the pair of second surfaces 12, 12 are flat surfaces parallel to each other, the first member 10 is stably arranged between the adjacent vertebral bodies VB even in the rotated state. That is, even if a force is applied to narrow the gap between the adjacent vertebral bodies VB, the first member 10 is less likely to return to its original state (i.e., the state of being inserted into the intervertebral disc) and is more likely to be maintained in the rotated state.

[0044] Note that the handle 50 may be fixed to the second end portion 10b of the first member 10. However, if the handle 50 is made detachable from the second end portion 10b of the first member 10, the handling property of the first member 10 and the like can be improved.

[0045] When the first member 10 is rotated, the second member 20 is moved along the first member 10. Specifically, the second member 20 is moved along the first member 10 such that the second end portion 10b of the first member 10 is inserted into the groove portion 20h from the first end portion 20a of the second member 20. Then, with the first member 10 accommodated in the groove portion 20h of the second member 20, the first end portion 20a of the second member 20 is inserted into the gap between the adjacent vertebral bodies VB (see FIGS. 4(C) and 8(A)). And when the second member 20 is inserted until the end face of the flange portion 25 reaches a predetermined position of the second end portion 10b of the first member 10, the edge of the first end portion 20a of the second member 20 is arranged at a position retreated by a predetermined amount from the end face of the first end portion 10a of the first member 10. Note that even in this state, the insertion amount of the first end portion 10a of the first member 10 into the gap between the adjacent vertebral bodies VB is adjusted so that the edge of the first end portion 20a of the second member 20 is inserted into the gap between the adjacent vertebral bodies VB.

[0046] When the second member 20 is moved along the first member 10, the second member 20 is arranged such that its pair of side walls 22, 22 face the pair of second surfaces 12, 12 of the first member 10, respectively. Moreover, the second member 20 is in a state where its bottom wall 21 is in contact with the first surface 11 (the lower surface in FIG. 8) located on the nerve side (exiting nerve root side) of the pair of first surfaces 11, 11 of the first member 10. Then, the nerve can be protected from an instrument or the like operated at the position of the triangle TR of the cambine by the bottom wall 21 and the side walls 22 of the second member 20. Moreover, since the outer surfaces of the pair of side walls 22, 22 of the second member 20 are in contact with the opposing surfaces of the vertebral bodies VB, respectively, even when a force is applied to narrow the gap between the adjacent vertebral bodies VB, the second member 20 makes it easier to maintain the gap between the vertebral bodies VB. Note that even when the first end portion 10a is inserted between the vertebral bodies VB, the second end portion 20b of the second member 20 is in a state of being exposed outside the patient's body.

[0047] When the first end portion 20a of the second member 20 is inserted into the gap between the adjacent vertebral bodies VB, the first member 10 and the guide member 30 are removed (see FIGS. 5(B), 8(B), and 9(A)), and only the second member 20 remains between the vertebral bodies VB (see FIGS. 5(C) and 9(B)). Then, since the second end portion 20b of the second member 20 is exposed outside the patient's body, a route (space) communicating from outside the patient's body to between the vertebral bodies VB is formed by the groove portion 20h of the second member 20 (see FIGS. 8(C) and 9(B)).

[0048] Thus, if a route (space) communicating from outside the patient's body to between the vertebral bodies VB is formed by the groove portion 20h of the second member 20, a shaver 40 or other instruments (such as a ring curette, etc.) can be inserted between the vertebral bodies VB through this route (groove portion 20h) (see FIG. 10), and the intervertebral disc or the vertebral bodies VB themselves between the vertebral bodies VB can be resected. Note that the shaver 40 may also be provided with a through hole penetrating in the axial direction through which the guide member 30 can be inserted, and the insertion of the shaver 40 and the resection operation by the shaver 40 may be performed with the guide member 30 inserted. Then, since the movement range of the shaver 40 can be limited, it becomes easier to prevent the shaver 40 from contacting the surrounding tissues during the insertion of the shaver 40 and the resection operation by the shaver 40.

[0049] Also, through this route (groove portion 20h), the implant IP can be placed at a predetermined position between the vertebral bodies VB by the implant insertion instrument 45 (see Fig. 9(B)). Moreover, since the groove portion 20h of the second member 20 is open on the side opposite to the bottom wall 21, even if the instrument or the implant IP is larger than the cross-sectional area of the groove portion 20h, as long as its width is shorter than the distance W2 between the inner surfaces of the pair of side walls 22, 22, it can be inserted between the vertebral bodies VB through the route (groove portion 20h). For example, an implant IP with a height suitable for between the vertebral bodies VB is used, and although the width of the implant IP is shorter than the distance W2 between the inner surfaces of the pair of side walls 22, 22, its height may be larger than the height T2 of the pair of side walls 22, 22 (in other words, the depth of the groove portion 20h). However, since the second member 20 is open on the side opposite to the bottom wall 21, even such an implant IP can be inserted between the vertebral bodies VB. In particular, if an implant IP with a variable height is used, it can be adjusted to an appropriate height after being inserted between the vertebral bodies VB. In this case, if the implant IP is made the smallest (lowest in height), even an implant IP that is several times higher than the height T2 of the pair of side walls 22, 22 in the state of being inserted between the vertebral bodies VB can be inserted between the vertebral bodies VB. Then, compared with the height of the implant IP actually placed between the vertebral bodies VB, the hole formed in the patient (that is) can be made smaller, so the burden on the patient during the operation can be reduced. Also, when collecting the removed tissue or the like, even if the removed tissue or the like is larger than the cross-sectional area of the groove portion 20h, it can be collected through the route (groove portion 20h) as long as it is up to a certain size. Then, it is not necessary to make the collected tissue smaller, so the burden on the operator can be reduced and the operation time can also be shortened.

[0050] As described above, by using the surgical instrument 1 of the present embodiment, the space between the vertebral bodies VB can be easily and surely widened by the first member 10, and a route can be formed to communicate between the outside of the body and the space between the vertebral bodies VB by the groove portion 20h of the second member 20. Moreover, even an instrument or the like having a cross-sectional area larger than that of the groove portion 20h of the second member 20 can be inserted between the vertebral bodies VB, and even a tissue or the like having a cross-sectional area larger than that of the groove portion 20h of the second member 20 can be recovered from between the vertebral bodies VB.

[0051] In addition, when the gap between adjacent vertebral bodies VB cannot be widened to a predetermined interval at once, a plurality of first members 10 and second members 20 having different sizes may be used to widen it to a desired interval. In this case, a small first member 10 and a small second member 20 are used to widen the space between the vertebral bodies VB by the method described above, and the small second member 20 is disposed between the vertebral bodies VB. Then, the large first member 10 is disposed between the vertebral bodies VB through the groove portion 20h of the small second member 20. Specifically, as the large first member 10, a member in which the distance T1 between the pair of first surfaces 11, 11 is longer than the distance T1 between the pair of first surfaces 11, 11 of the small first member 10 but the same as or shorter than the distance W2 between the inner surfaces of the pair of side walls 22, 22 of the small second member 20 is disposed between the vertebral bodies VB through the groove portion 20h of the small second member 20. Then, after removing the small second member 20, the large first member 10 is rotated to further widen the space between the vertebral bodies VB, and then the large second member 20 is inserted. Finally, if the large first member 10 is removed, a route can be formed to communicate from the outside of the body to between the vertebral bodies VB by the large second member 20 with the gap between the adjacent vertebral bodies VB widened to a predetermined interval. Note that the sizes of the small first member 10 and the large first member 10 are not particularly limited, but if the distance T1 between the pair of first surfaces 11, 11 of the small first member 10 and the distance W1 between the pair of second surfaces 12, 12 of the large first member 10 are the same length, the surgery and procedures will be easier to perform.

[0052] In order to easily widen the gap between adjacent vertebral bodies VB, it is desirable to first use the first member 10 having a square cross section before using the first member 10 having a rectangular cross section as described above. Between the vertebral bodies VB of the patient on whom the treatment is performed by the surgical instrument 1 of the present embodiment, a circular hole for inserting the first member 10 is formed before performing the treatment for widening the gap between the vertebral bodies VB. Therefore, if the first member 10 having a square cross section is first inserted between adjacent vertebral bodies VB, then it becomes easier to perform the operation of rotating the first member 10 having a rectangular cross section to widen the gap between adjacent vertebral bodies VB. The first member 10 having a square cross section used here only needs to have a cross-sectional shape and size that can be inserted into the above-described circular hole. For example, the first member 10 only needs to be formed such that the distance T1 between the surfaces of the pair of first surfaces 11, 11 and the distance W1 between the surfaces of the pair of second surfaces 12, 12 are the same, and the lengths of the distance T1 and the distance W1 are substantially the same as the diameter of the circular hole.

[0053] When using such a first member 10 having a square cross section, the treatment is performed as follows. First, the first end portion 10a of the first member 10 having a square cross section is inserted between adjacent vertebral bodies VB. At this time, the first member 10 having a square cross section is inserted between adjacent vertebral bodies VB so that the pair of first surfaces 11, 11 or the pair of second surfaces 12, 12 thereof are in contact with the opposing surfaces of the vertebral bodies VB. Next, the first member 10 is rotated to confirm that the distance between the vertebral bodies VB is the same as the distance W1 between the surfaces of the first member 10, and the state between the vertebral bodies VB of the patient is confirmed. If the patient is of a small build and the gap between the vertebral bodies VB cannot be widened, the second member 20 is moved along the first member 10 having a square cross section so that the outer surfaces of the pair of side walls 22, 22 are in contact with the opposing surfaces of the vertebral bodies VB, respectively, and the first end portion 20a of the second member 20 is inserted into the adjacent vertebral bodies VB. Then, after pulling out the first member 10 having a square cross section, a treatment for excising the intervertebral disc or the vertebral bodies VB themselves between the vertebral bodies VB and a treatment for placing the implant IP are performed. For the second member 20 used at this time, a second member 20 with a square cross-section having a groove portion 20h is used. Specifically, a second member 20 is used in which the distance W2 between the inner surfaces of the pair of side walls 22, 22 is the same as the distance W1, and the height T2 of the pair of side walls 22, 22 is the same as the distance T1. Also, when the gap between the vertebral bodies VB can be widened, after pulling out the first member 10 with a square cross-section, the first end portion 10a of the first member 10 with a rectangular cross-section is inserted between the adjacent vertebral bodies VB, and the first member 10 with a rectangular cross-section is rotated to widen the gap between the adjacent vertebral bodies VB. Thereafter, using the first member 10 with a rectangular cross-section and the second member 20 suitable for this first member 10, after widening the gap between the adjacent vertebral bodies VB to a desired interval, an operation of excising the intervertebral disc between the vertebral bodies VB or the vertebral bodies VB themselves and an operation of placing the implant IP are performed. When using the guide member 30 when inserting the first member 10 with a square cross-section, the first member 10 with a square cross-section may be pulled out so as to leave the guide member 30, and the first end portion 10a of the first member 10 with a rectangular cross-section may be inserted into the gap between the adjacent vertebral bodies VB using the guide member 30.

[0054] Note that the sizes of the first member 10 with a square cross-section, the second member 20 with a square cross-section, the first member 10 with a rectangular cross-section, and the second member 20 to be used are not particularly limited, and those suitable for the physique of the patient to be operated on can be used.

[0055] For example, in the case of a patient with an average Japanese physique, after using the first member 10 with a square cross-section having a side length of 8 mm, the first member 10 with a rectangular cross-section having a distance T1 of 8 mm and a distance W1 of 10 mm, and the second member 20 suitable for this first member 10 with a rectangular cross-section are used, it becomes easier to widen the gap between the adjacent vertebral bodies VB to a desired interval. Also, for a Japanese patient with a large build, after using the first member 10 with a square cross-section having a side length of 8 mm, a first member 10 with a rectangular cross-section where the distance T1 is 8 mm and the distance W1 is 10 mm, and a second member 20 suitable for this first member 10 with a rectangular cross-section are used. Then, by using a first member 10 with a rectangular cross-section where the distance T1 is 10 mm and the distance W1 is 12 mm, and a second member 20 suitable for this first member 10 with a rectangular cross-section, it becomes easier to widen the gap between adjacent vertebral bodies VB to a desired interval. And, when it is not possible to widen the space between the vertebral bodies VB in a Japanese patient with a small build, only the first member 10 with a square cross-section having a side length of 8 mm and the second member 20 with a square cross-section suitable for this first member 10 with a square cross-section need to be used.

[0056] <Regarding the first member 10> Regarding the first member 10, the connecting portion between the pair of first surfaces 11, 11 and the pair of second surfaces 12, 12 may be an edge or may be chamfered. Also, the pair of first surfaces 11, 11 and the pair of second surfaces 12, 12 may be connected by a curved surface. Note that the cross-section orthogonal to the axial direction of the first member 10 being substantially rectangular includes those in which the connecting portion between the pair of first surfaces 11, 11 and the pair of second surfaces 12, 12 is chamfered, and those in which the pair of first surfaces 11, 11 and the pair of second surfaces 12, 12 are connected by a curved surface.

[0057] Also, the cross-section of the first member 10 orthogonal to its axial direction is not limited to being substantially rectangular as described above. As described above, a shape having a pair of first surfaces 11, 11 parallel to each other and a pair of second surfaces 12, 12 parallel to each other with different surface-to-surface distances is sufficient. For example, the cross-section of the first member 10 orthogonal to its axial direction may be formed into a parallelogram with different lengths of non-parallel sides, a hexagon or octagon where the lengths of some sides are different from those of other sides, etc.

[0058] Furthermore, in the above example, a pair of inclined surfaces 11f, 11f are provided at the first end portion 10a of the first member 10, but it is not necessary to provide a pair of inclined surfaces 11f. Only the inclined surface 11f continuous with one of the first surfaces 11 may be provided at the first end portion 10a of the first member 10. Also, it is not necessary to provide the inclined surface 10f at the first end portion 10a of the first member 10. If the inclined surface 11f is provided at the first end portion 10a of the first member 10, it becomes easier to insert the first end portion 10a of the first member 10 between the vertebral bodies.

[0059] Furthermore, in the above example, the end surface of the first end portion 10a of the first member 10 is formed as a flat surface orthogonal to the pair of first surfaces 11, 11 and / or the pair of second surfaces 12, 12, but it is not necessarily orthogonal to the pair of first surfaces 11, 11 and / or the pair of second surfaces 12, 12, nor does it have to be a flat surface. Also, the tip of the first end portion 10a of the first member 10 may be an edge where the pair of inclined surfaces 11f, 11f are connected.

[0060] Furthermore, when the guide member 30 is not used, through holes 10h and recesses 10d do not have to be provided in the first member 10.

[0061] Furthermore, as shown in FIG. 24, a through hole h intersecting the axial direction of the first member 10 may be provided at the second end portion 10b of the first member 10. If such a through hole h is formed, the first member 10 can be rotated around the axis of the first member 10 without using a special handle or the like, and the first member 10 can be pulled out from between adjacent vertebral bodies VB or from the second member 20. For example, if a shaft-like member is inserted through the through hole h and the shaft-like member is rotated around the axis of the first member 10, the first member 10 can be rotated around the axis of the first member 10. Also, if a shaft-like member is inserted through the through hole h and the shaft-like member is moved in the axial direction of the first member 10, the first member 10 can be pulled out from between adjacent vertebral bodies VB or from the second member 20.

[0062] <Regarding the second member 20> When the cross-section of the second member 20 orthogonal to the axial direction of the first member 10 is substantially rectangular, the distance W2 between the inner surfaces of the pair of side walls 22, 22 is formed to be the above-described length. That is, when the pair of first surfaces 11, 11 and the pair of second surfaces 12, 12 are orthogonal in the first member 10, the second member 20 is formed such that the distance W2 between the inner surfaces of the pair of side walls 22, 22 is the same as or slightly longer than the distance W1 between the surfaces of the pair of second surfaces 12, 12 of the first member 10. On the other hand, even when the pair of first surfaces 11, 11 and the pair of second surfaces 12, 12 are non-orthogonal in the cross-section orthogonal to the axial direction of the first member 10, the second member 20 may be formed to have a size such that the first member 10 and the second member 20 can move (slide) relative to each other. Specifically, the second member 20 may be formed such that the width of the first member 10 in the direction parallel to the pair of first surfaces 11, 11 and orthogonal to the axial direction and the distance between the inner surfaces of the pair of side walls 22, 22 of the second member 20 are substantially the same length.

[0063] In addition, as the shape of the second member 20, those having a cross-sectional shape as shown in FIG. 16 can also be used. For example, as shown in FIG. 16(A), it may be formed in a shape with the bottom wall 21 on an arc (U-shaped cross-section). Also, as shown in FIG. 16(B), it may be formed in a shape without one side wall 22, that is, a shape provided with only the bottom wall 21 and one side wall 22 (L-shaped cross-section). Further, as shown in FIG. 16(C), it may be formed in a shape provided with only one side wall 22 without the bottom wall 21 (V-shaped cross-section). When the second member 20 has the shape as shown in FIG. 16(B), the function of maintaining the gap between the adjacent vertebral bodies VB against a force that narrows the gap between the adjacent vertebral bodies VB cannot be sufficiently exerted. For this reason, when the second member 20 has the shape as shown in FIG. 16(B), for example, it is desirable to maintain the gap between the adjacent vertebral bodies VB by a method such as separately arranging an instrument for maintaining the gap between the adjacent vertebral bodies VB between the adjacent vertebral bodies VB. Also, as shown in FIG. 16(D), it may be formed in a shape provided with a ceiling wall 23 connecting the upper ends of the pair of side walls 22, 22 (rectangular cross-section). In this case, the width of the bottom wall 21 and the width of the ceiling wall 23 are the same length, but the width of the pair of side walls 22, 22 and the width of the bottom wall 21 and the ceiling wall 23 may be different lengths.

[0064] <Connection of the first member 10 and the second member 20> Grooves or the like extending along the axial direction may be formed on the first surface 11 and the second surface 12 of the first member 10. In this case, if a rail-shaped protrusion or a simple protrusion extending along the axial direction of the groove portion 20h is provided on the bottom wall 21 and the side wall 22 of the groove portion 20h of the second member 20, the first member 10 can be moved along the axial direction of the groove portion 20h with respect to the second member 20 in a positioned state. In particular, when a rail-shaped protrusion 20p extending along the axial direction of the groove portion 20h is formed on the bottom wall 21 and the side wall 22 of the groove portion 20h (see FIGS. 15(A) and (B)), it is desirable to provide a groove on the implant IP that engages with the rail-shaped protrusion. Then, when the implant IP is disposed between the vertebral bodies through the groove portion 20h of the second member 20, the implant IP can be implanted at an appropriate position (that is, the position where the first end portion 20a of the second member 20 is disposed) without using a special instrument. Further, even if bent pieces 20r bent inward are provided at the upper end edges of the pair of side walls 22, 22 of the second member 20 (see FIG. 15(C)), the same effect can be obtained.

[0065] <Regarding the guide member 30> The shape of the stopper 32 of the guide member 30 is not limited to the spherical shape as described above, and any shape may be used. For example, a simple bar or a plate-shaped member may be attached to the tip of the wire portion 31 to serve as the stopper 32. Even in that case, the recess 10d of the first member 10 may be formed in a shape and size that can accommodate the stopper 32. Further, if the stopper 32 can prevent the first member 10 from falling off or the like, the recess 10d may not be provided on the end surface of the first end portion 10a of the first member 10.

[0066] <Regarding the shaver 40> The shaver 40 may be a general shaver or a shaver 40 having a shape as shown in FIG. 13. That is, the shaver 40 shown in FIG. 13 has a shaft portion 41 and a handle 42 provided at one end of the shaft portion 41, and a cutting portion 43 is provided at the other end of the shaft portion 41. The cutting portion 43 has a substantially rectangular cross-section, and cutting edges 43c are provided on edge portions located on both sides of one side thereof. These cutting edges 43c are formed to exhibit a cutting function only when rotated in a predetermined direction. With such a configuration, if the cutting edges 43c are brought into contact with a vertebral body VB or the like and the handle 42 is rotated, the vertebral body VB or the like can be resected. For example, if the handle 42 is rotated forward and backward about 90 degrees to the left and right, the vertebral body VB or the like can be resected. On the other hand, since the nerve side (exiting nerve root side) is not resected, the resection operation can be performed safely. In addition, as described above, the shaver 40 may be provided with a through hole that penetrates in the axial direction through which the guide member 30 can be inserted. In this case, if the central axis of the through hole and the central axis of the shaver 40 are coaxial, when performing an operation of rotating the shaver 40, the shaver 40 can be rotated around the central axis of the through hole. Moreover, since the movement of the shaver 40 in the axial direction of the through hole can be prevented, contact between the cutting edges 43c of the shaver 40 and the surrounding tissue can be suppressed. Then, it becomes easier to prevent the occurrence of work mistakes and the like.

[0067] <Regarding the handle 50> The handle 50 only needs to be able to rotate the first member 10 around its axis when the handle 50 is attached to the second end portion 10b of the first member 10, and its shape and structure are not particularly limited. For example, the handle 50 itself is formed as a substantially strip-shaped member, and an engagement hole 50h that penetrates (or does not penetrate) the member is provided. Then, when the handle 50 is rotated around the axis of the first member 10 with the second end portion 10b of the first member 10 inserted into the engagement hole 50h, the first member 10 may be rotated around its axis together with the handle 50. In this case, the shape of the engagement hole 50h is not particularly limited, and it only needs to be a shape that restricts the movement of the handle 50 around the axis of the first member 10 relative to the first member 10. For example, if the cross-sectional shape of the engagement hole 50h and the cross-sectional shape of the second end portion 10b of the first member 10 are made to be substantially the same shape and the same size, the above-described function can be exhibited. Specifically, if the cross-sectional shape of the engagement hole 50h and the cross-sectional shape of the second end portion 10b of the first member 10 are formed into a rectangular cross-section such as a rectangle or a square, or a polygonal cross-section such as a triangle or a pentagon, the above-described function can be exhibited (see FIGS. 4, 18, and 25(B)).

[0068] Alternatively, a pair of engagement grooves 10g, 10g recessed from a pair of first surfaces 11, 11 or a pair of second surfaces 12, 12 may be formed in the second end portion 10b of the first member 10 (see FIGS. 20 and 21), and an engagement portion 51 that engages with the pair of engagement grooves 10g, 10g may be provided on the handle 50. If such a pair of engagement grooves 10g, 10g are provided in the second end portion 10b of the first member 10 and the engagement portion 51 is provided on the handle 50, it becomes easier to pull out the first member 10 from between the vertebral bodies VB or from the second member 20.

[0069] The shapes of the pair of engagement grooves 10g, 10g and the shape of the engagement portion 51 are not particularly limited, and as long as the two are engaged, they may be formed in a shape that restricts the axial movement of the handle 50 with respect to the first member 10. That is, when the handle 50 is moved in the axial direction of the first member 10, it is sufficient that the first member 10 can be moved in the axial direction together with the handle 50. For example, a pair of engagement grooves 10g, 10g recessed from the pair of second surfaces 12, 12 are formed at the second end portion 10b of the first member 10 (see FIG. 17). In this case, as the engagement portion 51, a pair of engagement protrusions 51p, 51p are provided, and if the distance between the inner surfaces of the pair of engagement protrusions 51p, 51p is made longer than the distance between the inner bottom surfaces of the pair of engagement grooves 10g, 10g and shorter than the distance between the pair of first surfaces 12, 12, the above function can be exhibited.

[0070] <Regarding the handle 50B> In addition, as the handle, a handle 50B having a shape as shown in FIGS. 25(A) and 27(A) may be used. This handle 50B has a substantially T-shaped configuration and includes a shaft portion 51B connected to the second end portion 10b of the first member 10 and a holding portion 52B provided at the proximal end of the shaft portion 51B. The holding portion 52B is a member having a portion a extending from the proximal end of the shaft portion 51B so as to intersect the axial direction. The shape of the holding portion 52B is not particularly limited, and it may be formed in a shape that is easy for the operator to hold the handle 50B. In particular, even when the first end portion 10a of the first member 10 is inserted between the vertebrae VB, as will be described later, it may be formed in a shape that is easy to rotate the handle 50B around the axis of the first member 10. The shaft portion 51B has an engagement hole 51h (see FIG. 27) into which the second end portion 10b of the first member 10 is inserted at its tip. When the second end portion 10b of the first member 10 is inserted into the engagement hole 51h, the rotation of the first member 10 with respect to the shaft portion 51B is fixed. That is, when the handle 50B is rotated around the axis of the first member 10, the engagement hole 51h of the shaft portion 51B is formed so that the first member 10 also rotates around its axis together with the handle 50B. Note that the shape of the engagement hole 51h is not particularly limited, and like the handle 50, it may have a shape that restricts the movement of the handle 50 around the axis of the first member 10 when it engages with the second end portion 10b of the first member 10. Also, when using the handle 50B, as shown in FIG. 25(B), a recess g may be provided in the second end portion 10b of the first member 10. In this case, an engagement member b that engages with the recess g is provided in the engagement hole 51h of the shaft portion 51B of the handle 50B when connected to the first member 10. If such an engagement member b is provided, when the engagement hole 51h of the shaft portion 51B is inserted into the second end portion 10b of the first member 10, the engagement member b engages with the recess g to fix the movement of the handle 50B in the axial direction of the first member 10. Then, with the handle 50B connected to the first member 10, if the handle 50B is moved in the axial direction of the first member 10, the first member 10 can be pulled out from between the adjacent vertebrae VB or from the second member 20. The structure of the engagement member b is not particularly limited. For example, as shown in FIGS. 27(B) and (C), a sphere can be used as the engagement member b. When such an engagement member b is adopted, it is provided so that it cannot move in the axial direction of the engagement hole 51h but can move in the radial direction of the engagement hole 51h, and is biased toward the engagement hole 51h by a spring or the like. Then, while reducing the resistance when inserting the engagement hole 51h of the shaft portion 51B into the second end portion 10b of the first member 10, the second end portion 10b of the first member 10 can be engaged with the engagement hole 51h. Also, when inserting the first member 10 between adjacent vertebral bodies VB and using the guide member 30, it is necessary to form a through hole 50g in the handle 50B to insert the guide member 31 of the guide member 30 along the axial direction of the shaft portion 51B. Further, the handle 50B may also be used for the shaver 40. That is, instead of the handle 42 of the shaver 40 shown in FIG. 13, the handle 50B may be detachably attached to the shaft portion 41 of the shaver 40 (see FIG. 26(A)). In this case, one end 41b of the shaft portion 41 of the shaver 40 may be formed such that when the handle 50B is rotated around the axis of the shaft portion 41, the shaft portion 41 also rotates around its axis together with the handle 50B. For example, it is desirable that one end 41b of the shaft portion 41 of the shaver 40 has the same cross-sectional shape as the second end portion 10b of the first member 10 to which the handle 50B is connected (see FIG. 26(B)). When providing the engaging member b described above on the shaft portion 51B of the handle 50B, it is desirable to provide a recessed portion that engages with the engaging member b at one end 41b of the shaft portion 41 of the shaver 40, like the second end portion 10b of the first member 10, but it is not necessarily required to provide a recessed portion as shown in FIG. 26(B).

[0071] <Hammer 60> When inserting the first end portion 10a of the first member 10 between the vertebral bodies VB, if the insertion resistance is large, it is difficult for the operator to push in the first member 10. In that case, the end face of the second end portion 10b of the first member 10 is struck with a hammer or the like to insert the first end portion 10a of the first member 10 between the vertebral bodies VB. However, when the wire portion 31 of the guide member 30 is inserted through the first member 10, the wire portion 31 gets in the way when the end face of the second end portion 10b of the first member 10 is struck with a hammer or the like. Therefore, when striking the end face of the second end portion 10b of the first member 10 with the wire portion 31 of the guide member 30 inserted through the first member 10, it is desirable to use a hammer 60 having the following shape.

[0072] As shown in FIG. 19, the hammer 60 has a handle portion 61 held by the operator and a hammer head 62 provided at the axial end of the handle portion 61.

[0073] The hammer head 62 is provided at the axial end of the handle portion 61 such that its central axis is orthogonal to the axial direction of the handle portion 61. On both end faces in the axial direction of this hammer head 62, striking surfaces 62s, 62s for striking the first member 10 are provided. Note that on the striking surfaces 62s, 62s, a flat surface orthogonal to the central axis of the hammer head 62 is provided at a position where the central axis of the hammer head 62 passes through the striking surfaces 62s, 62s.

[0074] An insertion groove 62c is provided in the hammer head 62 at an intermediate position between the striking surfaces 62s, 62s in the central axis direction thereof. This insertion groove 62c is a groove having an opening in a surface that intersects the striking surface 62s of the hammer head 62, in other words, a surface formed so as to surround the central axis direction of the hammer head 62 (hereinafter sometimes referred to as the side surface of the hammer head 62). This insertion groove 62c is formed such that its axial direction (in the case of FIG. 19(A), the direction perpendicular to the paper surface) intersects the central axis direction of the hammer head 62. For example, in FIG. 19, the insertion groove 62c is formed such that its axial direction is orthogonal to the central axis direction of the hammer head 62. This insertion groove 62c is formed such that its width (in the case of FIG. 19(A), the length in the vertical direction of the paper surface) is longer than the axial diameter of the wire portion 31. Further, this insertion groove 62c is formed such that its depth (in the case of FIG. 19(A), the length in the left-right direction of the paper surface) is slightly longer than the distance from the surface of the hammer head 62 to the central axis (hereinafter sometimes referred to as the radius of the hammer head 62) (for example, longer by the length of the radius of the wire portion 31).

[0075] Further, the hammer head 62 is formed with guide grooves 62g that communicate between the striking surfaces 62s, 62s. For example, in FIG. 19, the guide grooves 62g are formed such that their axial directions are parallel to the central axis of the hammer head 62. This guide groove 62g is a groove recessed from the side surface of the hammer head 62, that is, a groove having an opening in the side surface of the hammer head 62. This guide groove 62g is formed by a first guide groove 62a that communicates between one striking surface 62s and the insertion groove 62c, and a second guide groove 62b that communicates between the other striking surface 62s and the insertion groove 62c. The openings of the first guide groove 62a and the second guide groove 62b formed in the side surface of the hammer head 62 are formed at positions rotated 180 degrees around the central axis of the hammer head 62. That is, the first guide groove 62a and the second guide groove 62b are formed so as to recess from opposite directions toward the central axis of the hammer head 62 from positions rotated 180 degrees around the central axis of the hammer head 62 on the side surface of the hammer head 62 (see FIG. 19(B)). Moreover, when the wire portion 31 is brought into contact with the inner bottom surfaces of the first guide groove 62a and the second guide groove 62b respectively, the central axis of the wire portion 31 is formed so as to substantially coincide with the central axis of the hammer head 62. The central axis of the wire portion 31 substantially coinciding with the central axis of the hammer head 62 includes cases where there is a slight deviation in the radial direction of the hammer head 62 or where there is a slight inclination between the central axis of the wire portion 31 and the central axis of the hammer head 62.

[0076] And the insertion groove 62c and the second guide groove 62b are formed such that their inner bottom surfaces are substantially at the same position in the radial direction of the hammer head 62. The inner bottom surfaces of the insertion groove 62c and the second guide groove 62b being substantially at the same position in the radial direction of the hammer head 62 includes cases where there is a slight deviation in the radial direction of the hammer head 62.

[0077] Since the hammer 60 has the shape as described above, if the following steps are taken, even when the wire portion 31 of the guide member 30 is inserted into the first member 10, the end face of the second end portion 10b of the first member 10 can be struck by a hammer or the like using the striking surface 62s of the hammer head 62 of the hammer 60.

[0078] As shown in Fig. 20(A), first, insert the wire portion 31 into the insertion groove 62c of the hammer head 62 so that the axial direction of the wire portion 31 is parallel to the axial direction of the insertion groove 62c. Then, arrange it so that the wire portion 31 contacts the inner bottom surface of the insertion groove 62c.

[0079] Next, rotate the hammer 60 around the axis of the handle portion 61. In other words, rotate the hammer 60 around an axis orthogonal to the central axis of the hammer head 62. Then, since the inner bottom surfaces of the insertion groove 62c and the second guide groove 62b are formed to be approximately at the same position in the radial direction of the hammer head 62, the wire portion 31 can be arranged in the groove 62a of the guide groove 62g and the second guide groove 62b (Fig. 20(B)).

[0080] When the wire portion 31 is in contact with the inner bottom surfaces of both the first guide groove 62a and the second guide groove 62b (Fig. 21(A)), the wire portion 31 and the central axis of the hammer head 62 are in a coincident state. In this state, if the hammer head 62 is moved along the wire portion 31 toward the end face of the second end portion 10b of the first member 10, the end face of the second end portion 10b of the first member 10 can be struck by the striking surface 62s of the hammer head 62 (Fig. 21(B)).

[0081] Note that the hammer head 62 does not necessarily need to be provided with the insertion groove 62c. When the insertion groove 62c is not provided, a guide groove 62g may be formed on the side surface of the hammer head 62 so that an opening connecting between the striking surfaces 62s, 62s is formed. Then, the hammer head 62 is arranged so that the axial direction of the guide groove 62g is parallel to the axial direction of the wire portion 31 of the guide member 30, and the wire portion 31 is inserted into the guide groove 62g from the opening. Then, since the axial direction of the hammer head 62 and the axial direction of the wire portion 31 can be made to coincide, the hammer head 62 can be moved along the wire portion 31. Therefore, the end surface of the second end portion 10b of the first member 10 can be accurately struck by the striking surface 62s of the hammer head 62 of the hammer 60.

[0082] Further, the hammer head 62 only needs to have the striking surface 62s formed on the end surface in the axial direction, and the shape of the hammer head 62 is not particularly limited. The hammer head 62 may be formed in a columnar shape with a cylindrical side surface, or may have a recessed portion recessed from the side surface as shown in FIG. 19. As shown in FIG. 19, if a recessed portion is provided on the hammer head 62 from the side surface, the hammer head 62 and the hammer 60 can be lightened. Then, the advantage of improving the handleability of the hammer 60 can be obtained. Further, the striking surface 62s may be provided on both end surfaces in the central axis direction of the hammer head 62, or the striking surface 62s may be provided only on one end surface.

[0083] <Supply instrument 70> In the case of the second member 20 of the surgical instrument 1 of the present embodiment, a route communicating from outside the patient's body to between the vertebral bodies VB can be formed. However, since the upper part of the groove portion 20h is open, it is difficult to supply the bone to be transplanted between the vertebral bodies VB through the route. Therefore, when a route communicating from outside the patient's body to between the vertebral bodies VB is formed by the second member 20, if the following supply instrument 70 is used, the bone to be transplanted between the vertebral bodies VB can be more reliably supplied.

[0084] As shown in FIG. 22, the supply device 70 has a funnel-shaped portion 71 and a tubular portion 72 connected to the funnel-shaped portion 71.

[0085] The funnel-shaped portion 71 is a member provided with an opening at the upper part and a supply space 71h for accommodating the bone to be transplanted. This funnel-shaped portion 71 has a main body portion 71a having a conical bottom surface and a wall 71b extending from the upper end of the main body portion 71a. The region surrounded by the conical bottom surface of the main body portion 71a and the inner surface of the wall 71b is the supply space 71h. Further, a communication hole 71c for communicating between the supply space 71h and the outside is formed in the bottom surface of the main body portion 71a of the funnel-shaped portion 71. This communication hole 71c is formed at a position deviated in the radial direction of the main body portion 71a from the central axis 71s of the funnel-shaped portion 71.

[0086] The tubular portion 72 is a hollow tubular member and has an introduction passage 72h communicating between the base end and the tip end inside thereof. The base end portion of this tubular portion 72 is connected to the outer surface of the main body portion 71a of the funnel-shaped portion 71. Specifically, the tubular portion 72 is connected to the main body portion 71a of the funnel-shaped portion 71 so that the supply space 71h of the main body portion 71a of the funnel-shaped portion 71 and the introduction passage 72h communicate with each other through the communication hole 71c formed in the main body portion 71a of the funnel-shaped portion 71. And the tubular portion 72 is provided such that its axial direction, that is, the central axis 72s of the introduction passage 72h, is inclined with respect to the central axis 71s of the funnel-shaped portion 71. For example, the angle θ formed between the central axis 72s of the introduction passage 72h and the central axis 71s of the funnel-shaped portion 71 is about 30 to 60 degrees, preferably 45 degrees.

[0087] Further, the outer diameter of the tubular portion 72 is formed to be equal to or slightly shorter than the distance W2 between the inner surfaces of the pair of side walls 22, 22 of the groove portion 20h of the second member 20. That is, the tubular portion 72 is formed so as to be accommodated in the groove portion 20h of the second member 20 with the central axis 72s parallel to the axial direction of the groove portion 20h of the second member 20. Moreover, the tubular portion 72 is formed to be movable along the axial direction of the groove portion 20h of the second member 20 in a state of being accommodated in the groove portion 20h of the second member 20.

[0088] Since the supply instrument 70 has the above structure, the bone to be transplanted can be supplied between the vertebrae VB by the supply instrument 70 as follows.

[0089] First, the first end portion 20a of the second member 20 is in a state of being disposed between the vertebrae VB, and nothing is disposed in the groove portion 20h of the second member 20 (see Fig. 9(B)). In this state, the tubular portion 72 of the supply instrument 70 is accommodated in the groove portion 20h of the second member 20 with its central axis 72s parallel to the axial direction of the groove portion 20h of the second member 20. Then, if the tubular portion 72 of the supply instrument 70 is moved along the axial direction of the groove portion 20h of the second member 20, the tip of the tubular portion 72 can be disposed between the vertebrae VB (see Fig. 23(A)).

[0090] Next, if the bone to be transplanted is supplied into the supply space 71h of the funnel-shaped portion 71 of the supply instrument 70, the bone supplied into the supply space 71h of the funnel-shaped portion 71 is supplied between the vertebrae VB through the introduction passage 72h.

[0091] As described above, by using the supply instrument 70, the bone to be transplanted can be supplied between the vertebrae VB. Moreover, since the central axis 72s of the tubular portion 72 of the supply instrument 70 is inclined with respect to the central axis 71s of the funnel-shaped portion 71, the bone to be transplanted can be held stably in the supply space 71h of the funnel-shaped portion 71. That is, when the tubular portion 72 is disposed in the groove portion 20h of the second member 20, even if the groove portion 20h of the second member 20 is inclined with respect to the horizontal, since the central axis 72s of the tubular portion 72 is inclined with respect to the central axis 71s of the funnel-shaped portion 71, it becomes easier to hold the bone to be transplanted in the supply space 71h of the funnel-shaped portion 71.

[0092] When supplying bone between vertebrae VB through the introduction passage 72h of the tubular portion 72, the introduction passage 72h can also be moved by the weight of the bone. However, in order to reliably perform the procedure in a short time, as shown in FIGS. 22 and 23, it is desirable to push the bone in the introduction passage 72h between the vertebrae VB by a pushing member 75 having a shaft-like member 75a that can be inserted into the introduction passage 72h. In this case, it is desirable to form an insertion port 71g for inserting the shaft-like member 75a of the pushing member 75 at a position where a line extending the central axis of the wall 71b of the funnel-shaped portion 71 and the communication hole 71c intersects. If such an insertion port 71g is formed, the operation of pushing the bone in the introduction passage 72h by the pushing member 75 between the vertebrae VB becomes easier.

[0093] Also, the angle formed by the central axis 72s of the tubular portion 72 and the central axis 71s of the supply space 71h of the funnel-shaped portion 71 is not particularly limited as long as they are not parallel. However, if the angle θ formed by the two is about 30 to 60 degrees, it becomes easier to hold the bone to be transplanted in a stable state in the supply space 71h of the funnel-shaped portion 71, so it becomes easier to perform the technique of supplying the bone to be transplanted between the vertebrae VB. In particular, if the angle θ formed by the two is 45 degrees, when the tubular portion 72 is arranged in the groove portion 20h of the second member 20 in a state where a route communicating from outside the patient's body to between the vertebral bodies VB is formed by the second member 20, the central axis 71s of the supply space 71h of the funnel-shaped portion 71 can be maintained in a state close to vertical. Then, when the bone to be transplanted is supplied between the vertebrae VB, it becomes easier to hold the bone to be transplanted in a more stable state by the supply space 71h of the funnel-shaped portion 71.

[0094] Also, the outer diameter of the tubular portion 72 does not necessarily have to be formed to be equal to or slightly shorter than the distance W2 between the inner surfaces of the pair of side walls 22, 22 of the groove portion 20h of the second member 20. That is, the outer diameter of the tubular portion 72 may be larger than the distance W2 between the inner surfaces of the pair of side walls 22, 22 of the groove portion 20h of the second member 20. Even in that case, after removing the second member 20, if the tip of the tubular portion 72 is arranged between the vertebrae VB, the bone to be transplanted can be supplied between the vertebrae VB by the supply instrument 70.

Industrial Applicability

[0095] The surgical instrument of the present invention is suitable as an instrument for forming or holding the space between vertebrae in surgeries and procedures such as fixation between vertebrae, intervertebral expansion, discectomy, and insertion of foreign objects between vertebrae.

Explanation of Reference Numerals

[0096] 1 Surgical instrument 10 First member 10a First end 10b Second end 10g Engagement groove 11 First surface 11f Inclined surface 12 Second surface g Concave portion 20 Second member 20h Groove portion 21 Bottom wall 22 Side wall 30 Guide portion 31 Wire portion 32 Stopper 50 Handle 50h Engagement hole 51 Engagement portion 50B Handle 50g Through hole 51B Shaft portion 52B Holding portion 51h Engagement hole b Engagement member 60 Hammer 62 Hammer head 62g Guide groove 62a First guide groove 62b Second guide groove 62c Insertion groove 70 Feeding instrument 71 Funnel-shaped portion 71h Feeding space 71s Central axis 72 Tubular portion 72h Introduction passage 71g Insertion port C Spinal cord V Vertebra VB Vertebral body d intervertebral disc IP implant TR triangle of the cambin

Claims

1. An instrument for use in surgery between vertebrae of the spine, comprising: a first member having a pair of first surfaces parallel to each other and extending along a first direction, and a pair of second surfaces parallel to each other and intersecting the pair of first surfaces and extending along the first direction; a second member having a groove portion for accommodating the first member and communicating between a first end portion and a second end portion; the groove portion of the second member is formed such that the first member and the second member are relatively movable along the axial direction of the groove portion with the first direction of the first member parallel to the axial direction of the groove portion of the second member; in the first member, a through hole is formed communicating between an end surface of the first end portion in the first direction and an end surface of the second end portion in the first direction; a guide member having a wire portion inserted through the through hole; at a first end portion of the wire portion of the guide member, a stopper is provided for restricting movement of the first member along the wire portion of the guide member The surgical instrument is characterized by the above.

2. An instrument for use in surgery between vertebrae of the spine, comprising: a first member having a pair of first surfaces parallel to each other and extending along a first direction, and a pair of second surfaces parallel to each other and intersecting the pair of first surfaces and extending along the first direction; a second member having a groove portion for accommodating the first member and communicating between a first end portion and a second end portion; the groove portion of the second member is formed with a bottom wall extending along the axial direction of the groove portion and a pair of side walls parallel to each other and extending along the axial direction of the groove portion; the second member is formed such that the distance between the inner surfaces of the pair of side walls is such that the first member and the second member are relatively movable along the axial direction of the groove portion with the first direction of the first member parallel to the axial direction of the groove portion of the second member; in the first member, a through hole is formed communicating between an end surface of the first end portion in the first direction and an end surface of the second end portion in the first direction; a guide member having a wire portion inserted through the through hole; at a first end portion of the wire portion of the guide member, a stopper is provided for restricting movement of the first member along the wire portion of the guide member The surgical instrument is characterized by the above.

3. On an end surface of the first end portion of the first member in the first direction, a recess for accommodating the stopper of the guide member is provided The surgical instrument according to claim 1 or 2, characterized by the above.

4. A hammer for driving the first member between vertebrae of the spine is provided, On the hammer head of the hammer, a guide groove recessed from a surface intersecting both end faces of the hammer head is formed so as to communicate between both end faces of the hammer head, the guide groove is formed to have the same width as the shaft diameter of the wire portion of the guide member. The surgical instrument according to claim 1, 2 or 3, characterized in that.

5. On the hammer head of the hammer, an insertion groove recessed from a surface intersecting both end faces of the hammer head and wider than the shaft diameter of the wire portion of the guide member is formed, the insertion groove is formed such that its axial direction intersects the axial direction of the guide groove, the guide groove is a first guide groove formed between the insertion groove and one end face of the hammer head, and a second guide groove formed between the insertion groove and the other end face of the hammer head, the first guide groove is formed at a position rotated 180 degrees around the central axis of the hammer head with respect to an opening formed on a surface intersecting both end faces of the hammer head and an opening formed on a surface intersecting both end faces of the hammer head of the second guide groove. The surgical instrument according to claim 4, characterized in that.

6. The groove portion of the second member is formed such that the first member and the second member can move relative to each other along the axial direction of the groove portion with the first direction of the first member and the axial direction of the groove portion of the second member being parallel, at the second end portion of the first member, engagement grooves recessed from the pair of first surfaces or the pair of second surfaces are formed, a handle for operating the first member is provided, on the handle, an engagement hole through which the second end portion of the first member is inserted, and an engagement portion that engages with the engagement groove are provided, the engagement hole of the handle is formed in a shape that restricts the movement of the handle around the axis of the first member with respect to the first member when the second end portion of the first member is inserted through the engagement hole, the engagement portion of the handle is formed in a shape that restricts the movement of the handle in the axial direction of the first member with respect to the first member when the engagement portion is engaged with the engagement groove. The surgical instrument according to any one of claims 1 to 5, characterized in that.

7. The groove portion of the second member is formed such that the first member and the second member can move relative to each other along the axial direction of the groove portion with the first direction of the first member and the axial direction of the groove portion of the second member being parallel, at the second end portion of the first member, An engaging groove recessed from the pair of first surfaces and / or the pair of second surfaces is formed, and a handle for operating the first member is provided, and the handle is provided with an engaging hole through which the second end portion of the first member is inserted, and an engaging member that engages with the engaging groove, wherein the engaging hole of the handle is formed in a shape that restricts movement of the handle around the axis of the first member with respect to the first member when the second end portion of the first member is inserted through the engaging hole, and the engaging member of the handle is formed in a shape that engages with the engaging groove of the second end portion of the first member and restricts axial movement of the handle with respect to the first member when the second end portion of the first member is inserted through the engaging hole. The surgical instrument according to any one of claims 1 to 5, characterized in that.

8. The groove portion of the second member is formed such that the first member and the second member can move relative to each other along the axial direction of the groove portion with the axial direction of the first member and the axial direction of the groove portion of the second member being parallel, and a supply instrument for supplying bone to be transplanted between vertebrae of the spine is provided, and the supply instrument has a funnel-shaped portion having a supply space with an inner surface on which the bone to be transplanted is accommodated formed as a conical surface, and a tubular portion having an introduction passage communicating with the supply space of the funnel-shaped portion, wherein the tubular portion is provided such that its axial direction is inclined with respect to the central axis of the supply space of the funnel-shaped portion. The surgical instrument according to any one of claims 1 to 5, characterized in that.

9. The supply instrument has an insertion port for inserting an axial member into the introduction passage of the tubular portion in a wall forming the supply space. The surgical instrument according to claim 7, characterized in that.

10. The angle formed between the tubular portion and the central axis of the supply space of the funnel-shaped portion is 30 to 60 degrees. The surgical instrument according to claim 8 or 9, characterized in that.

11. The tubular portion is formed such that it can be accommodated in the groove portion of the second member with its axis parallel to the axial direction of the groove portion of the second member, and can move along the axial direction of the groove portion of the second member in that state. The surgical instrument according to claim 8, 9 or 10, characterized in that.

12. The first member has a shorter distance between the pair of first surfaces than the distance between the pair of second surfaces, and the groove portion of the second member has a bottom wall extending along the axial direction of the groove portion and a pair of side walls parallel to each other extending along the axial direction of the groove portion, and the second member The first member and the second member are formed to be relatively movable in a state where the inner surfaces of the pair of side walls face the pair of second surfaces. The surgical instrument according to any one of claims 2 to 11, characterized in that.

13. The groove portion of the second member is has a bottom wall extending along the axial direction of the groove portion and a pair of side walls parallel to each other extending along the axial direction of the groove portion, The inner surface between the pair of side walls of the second member is formed to have the same length as the length in the direction parallel to the pair of first surfaces of the first member and perpendicular to the first direction. The surgical instrument according to any one of claims 2 to 12, characterized in that.

14. The first member is formed such that the pair of first surfaces and the pair of second surfaces are perpendicular to each other. The surgical instrument according to any one of claims 1 to 13, characterized in that.

15. The first member is formed with an inclined surface inclined from one of the first surfaces toward the other first surface at the first end portion in the first direction. The surgical instrument according to any one of claims 1 to 14, characterized in that.

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