JP2006218050A - Burr-hole button for fixing skull bone valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To simply and sustainably fix the skull bone valve after craniotomy to the opened part of the skull bone in the width direction especially without any wiring and suturing. <P>SOLUTION: This burr-hole button 1 for fixing the skull bone valve is composed of a biocompatible material for closing a perforation D formed in opening the skull bone C and is provided with a shaft part 2 inserted and disposed in the perforation D, and flanged end plates 3 and 4 disposed in the both ends of the shaft part 2 and disposed in a position for clamping the skull bone C in the width direction. This burr-hole button 1 for fixing the skull bone valve is so formed that one end plate 4 to be disposed inside the skull bone C is formed into a disk shape, and the other end plate 3 to be disposed outside the skull bone C projects to roughly one side relative to the central line of the shaft part 2. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a skull hole fixing bar hole button.

Conventionally, there have been known skull valve fixing barhole buttons and skull perforation filling materials used to fix the cranial flap cut out during craniotomy in the field of neurosurgery to the craniotomy after the operation and repair the craniotomy. (For example, see Patent Document 1 and Patent Document 2).
In craniotomy, a patient's scalp is incised to expose the skull, a plurality of perforations are formed in a position surrounding the periphery of the craniotomy, and the skull between these perforations is cut with a line saw for osteotomy, etc. It is common to separate the skull flap from the skull. Then, through the craniotomy formed after the skull flap is cut off, the internal dura mater is incised, and the brain tissue is treated.

Then, to repair the craniotomy after the treatment of the brain tissue is completed, the skull flap is fitted to the craniotomy after covering the dura mater. However, since a gap is formed between the skull flap and the skull cut by a drill, a bone saw for cutting, and the like, the skull valve cannot be fixed to the skull simply by fitting.
Therefore, in Patent Document 1, a tapered bar hole button that tapers toward the insertion side into the perforation is used.
Patent Document 2 discloses a skull perforation filling material that is made of a porous calcium phosphate compound and has a tapered portion on at least one surface.
JP-A-5-237137 JP-A-4-246361

However, all of the barhole buttons and fillers of Patent Document 1 and Patent Document 2 are in a state of being caulked so that the gap is widened by pushing the tapered surface into the gap between the skull flap and the skull from the outside. To do. Therefore, although it is possible to fix the skull valve to the skull in the direction along the surface, it is difficult to fix the skull valve to the skull in the thickness direction. .
For this reason, after craniotomy, due to the micromotion of the brain in the skull, etc., the caulking state loosens over time, the barhole buttons and fillers fall off, and the skull valve sinks at the craniotomy .

  In order to prevent this, it is necessary to fix the skull valve and the skull by using wire or suture with metal wire or fiber together, which makes the craniotomy complicated and also burdens the patient. There is a problem of being big.

  The present invention has been made in view of the above-described circumstances, and it is simple and continuous to perform the cranial flap after craniotomy on the cranial head, particularly in the thickness direction thereof, without performing wiring or suturing. It is an object of the present invention to provide a skull valve fixing bar hole button that can be fixed to a cranium.

In order to achieve the above object, the present invention provides the following means.
The present invention is a skull valve fixing bar hole button made of a biocompatible material that closes a perforation that occurs when the skull is opened, and is disposed at both ends of the shaft portion inserted into the perforation, A scissor-shaped end plate portion disposed at a position sandwiching the skull in the thickness direction, and one end plate portion to be disposed inside the skull is formed in a disc shape and is formed outside the skull. A skull valve fixing barhole button is provided in which the other end plate portion to be disposed protrudes substantially in one side with respect to the center line of the shaft portion.

  In order to fix the skull flap to the skull according to the present invention, first, a plurality of perforations in a state where the skull flap has been removed are respectively protruded to one side from the center with one disk-shaped end plate portion inside the skull. With the other end plate portion outside the skull, the skull is sandwiched between the two end plate portions, and the skull valve fixing bar hole button is arranged so that the shaft portion is assigned to the perforation. At this time, since the outer end plate portion only protrudes approximately one side from the center of the shaft portion, it can be prevented from protruding to the side where the skull flap is disposed.

  Therefore, the skull valve can be inserted into the cranial head without being interrupted by the end plate portion even in the state where the skull hole fixing bar hole button of the present invention is disposed in all the perforations. After that, by rotating all the skull valve fixing barhole buttons around the central axis of the shaft part, the outer end plate part of the skull is stretched over both the skull and the outer surface of the skull valve. Can be arranged. Thereby, both the skull and the skull flap are sandwiched between the end plate portions at both ends of the shaft portion at a plurality of drilling positions, and are fixed in the thickness direction.

  Therefore, according to the present invention, the skull and the skull valve can be fixed in the thickness direction only by rotating the skull valve fixing bar hole button around the central axis of the shaft portion after the skull valve is mounted, and wiring and suture By eliminating the trouble of the ring, it is possible to reliably prevent the dropout over time and the settlement of the skull flap in the open head.

In the said invention, it is preferable that the end plate part which will be arrange | positioned outside the skull is formed in the substantially semicircular disk shape.
By configuring the outer peripheral edge of the end plate with an arc, the outer peripheral edge does not change in the radial direction of rotation when the skull valve fixing barhole button is rotated around the central axis of the shaft, and therefore the state of the skull surface It can be rotated smoothly without depending on.

Moreover, in the said invention, it is preferable that the end surface of the axial direction of the end plate part arrange | positioned inside a skull is formed in the substantially spherical shape.
By configuring the outer surface of the end plate placed inside the skull into a spherical shape that does not fluctuate even by rotation around the central axis of the shaft, fixing work can be performed without overloading the brain tissue etc. inside the skull. It can be carried out. In addition, the brain tissue is not stimulated after wearing.

Further, in the above invention, a recess into which a predetermined tool for rotating around the center line of the shaft portion can be inserted is formed on the end surface in the axial direction of the end plate portion to be disposed outside the skull. It is preferable.
A tool, for example, a wrench can be inserted into the recess to rotate the skull valve fixing bar hole button more easily, and the fixing operation of the skull valve can be facilitated. Further, since it is not necessary to apply an excessive force, the fixing work can be performed without applying a load to the tissue inside the skull.

Moreover, in the said invention, it is preferable that it is comprised with the bioabsorbable material.
By comprising in this way, since it is absorbed with time after completion of the craniotomy and no foreign matter remains after the restoration, it can be restored to a healthy state.

  Moreover, in the said invention, it is preferable that it is comprised with the elastic material. By giving the skull valve fixing barhole button a certain degree of elasticity, individual differences in the thickness of the skull can be absorbed to some extent and applied to more patients. Further, by sandwiching the skull valve and the skull by elasticity, it is possible to more effectively prevent loosening and dropping off due to vibration with time.

  According to the present invention, since the skull and the skull flap are sandwiched simultaneously by the end plate portions disposed on both sides of the shaft portion, both can be fixed in the thickness direction. As a result, unlike the conventional cranial flap fixing barhole button that only needs to be pushed in from the outside in the thickness direction, even if vibration is applied over time due to micromotion of the brain, etc. There is an effect that it is possible to more surely prevent inconvenience that the button falls off or the skull flap sinks.

A skull valve fixing barhole button according to an embodiment of the present invention will be described below with reference to FIGS.
As shown in FIG. 1, the skull hole fixing bar hole button 1 according to the present embodiment is made of, for example, a biocompatible calcium phosphate ceramic, and includes a cylindrical shaft portion 2, and the shaft portion 2. End plate portions 3 and 4 are provided at both ends in the axial direction.

The end plate portion 3 is provided on one end side of the shaft portion 2 and has a substantially semicircular shape so as to protrude only on one side with respect to a plane passing through the center line of the shaft portion 2.
The end plate portion 4 is provided on the other end side of the shaft portion 2, and is formed in a disk shape that protrudes radially outward from the outer peripheral surface of the shaft portion 2 over the entire circumference.

The end surfaces 3 a and 4 a of the end plate portions 3 and 4 disposed at both ends in the axial direction of the shaft portion 2 are each configured by a spherical surface having a center position on the central axis of the shaft portion 2.
A plurality of types of outer diameter dimensions of the shaft portion 2 are prepared according to the diameter dimension of the drill used for the craniotomy. In addition, a plurality of types of interval dimensions of the end plate portions 3 and 4 are prepared according to individual differences in the thickness dimension of the skull for each patient.

  A concave portion 5 extending in the axial direction is provided at the central position of the axial end surface 3a on the side where the end plate portion 3 of the shaft portion 2 is provided. For example, the recess 5 is formed in a quadrangular cross-sectional shape. As a result, a wrench G having a cross-sectional shape (see FIG. 4 (d)) fitted into the recess 5 can be inserted and can be easily rotated around the central axis of the shaft portion 2. .

The operation of the skull valve fixing barhole button 1 according to the present embodiment configured as described above will be described below.
In order to fix the skull valve B in the open head A to the skull C using the skull hole fixing barhole button 1 according to the present embodiment, as shown in FIGS. 3 (a) and 4 (a), First, as shown in FIGS. 3 (b) and 4 (b), a skull valve fixing barhole button 1 is arranged in an open head A having a plurality of perforations D formed in the skull C.

  At this time, the disc-shaped end plate portion 4 is disposed inside the skull C, the substantially semi-disc-shaped end plate portion 3 is disposed outside the skull C, and the shaft portion 2 is fitted along the perforation D. . Since there is a brain tissue protected by the dura mater E in the skull C, the end plate portion 4 is inserted between the skull C and the dura mater E so as not to be damaged. Thereby, as shown in FIG. 3B and FIG. 4B, the skull valve fixing bar hole button 1 is attached so that the skull C is sandwiched between the end plate portions 3 and 4.

  At this time, the end plate portion 3 is disposed so as to cover only the outer surface of the skull C, as shown in FIGS. 3B and 4B. Similarly, a skull valve fixing bar hole button 1 is arranged for each of the perforations D existing in the open head A.

As a result, the skull flap B that is subsequently inserted and arranged in the open head A is smoothly inserted and arranged as shown in FIGS. 3C and 4C without being obstructed by the end plate portion 3. can do. Further, since the inner end plate portion 4 is disposed so as to protrude inside the craniocephalus A at the position of each perforation D, just by inserting the skull valve B into the cranial head A, the skull with respect to the skull C The valve B is positioned in the thickness direction.
In this state, both the skull C and the skull valve B are placed on the upper surface of the end plate part 4 inside the barhole button 1 for fixing the skull valve.

  Thereafter, a wrench G is inserted into the recess 5 provided in the end surface 3a of the end plate portion 3, and as shown in FIGS. 3 (d) and 4 (d), in the direction indicated by the arrow F, The skull hole fixing barhole button 1 is rotated around the central axis of the shaft 2. Since the end plate portion 4 is formed in a disc shape over the entire circumference, the end plate portion 4 is maintained without changing the state in which both the skull C and the skull valve B are placed even by rotation. On the other hand, since the end plate portion 3 is formed in a semi-disc shape, a part of the end plate portion moves from the outer surface of the skull C to the outer surface of the skull valve B by rotation.

  Thereby, when it rotates to the position shown by FIG.3 (d) and FIG.4 (d), the skull C and the skull valve B will be simultaneously pinched | interposed between the endplate part 3 and the endplate part 4. FIG. . Accordingly, the skull valve B is fixed to the skull C in the thickness direction by the skull valve fixing barhole button 1 as shown in FIG.

  According to the skull hole fixing barhole button 1 according to the present embodiment, the skull valve B is moved with respect to the skull C only by rotating around the central axis of the shaft portion 2 after being arranged along all the perforations D. And can be fixed in the direction along the surface by a frictional force. Therefore, the open head A can be easily and more reliably closed in a short time.

  In addition, according to the skull valve fixing barhole button 1 according to the present embodiment, the skull valve B can be maintained in a state of being fixed in the thickness direction with respect to the skull C, so that the tapered member is pushed in from the outside as in the past. Unlike the above-described method, it is possible to avoid the occurrence of inconvenience that the skull flap B sinks over time or the skull valve B sinks. As a result, the head opening A can be restored quickly and in a healthy state.

  Further, according to the skull valve fixing bar hole button 1 according to the present embodiment, the end surface 4a of the end plate portion 4 is formed in a spherical shape, so that even if it is rotated around the central axis of the shaft portion 2, It is not necessary to change the position of the end face 4a. Since the end plate portion 4 is arranged inside the skull C, the fixing work can be performed so as not to apply an excessive load to the brain tissue inside the skull C by being configured in this way. In addition, even after the craniotomy is completed, it does not protrude greatly toward the brain tissue side, so that it is possible to avoid stimulating the brain tissue.

Moreover, since the end plate part 3 arranged outside the skull C also has an arc-shaped outer peripheral edge, it is possible to reduce the resistance received from the outer surface of the skull C when it is rotated, and to rotate it easily. Is possible. In addition, if a device such as floating the outer peripheral edge with respect to the skull C is applied, the end plate portion 3 is not limited to the semicircular shape but may be other polygonal shapes.
Further, although the concave portion has a quadrangular cross section, it may be configured in a triangular shape or a polygonal shape of pentagon or more instead. Moreover, you may form a some recessed part in the position eccentric from the center axis | shaft.
The end plate portion 3 is not necessarily integrated, and may be configured to be detachable. Moreover, you may decide to provide the unevenness | corrugation, groove | channel, etc. for improving a fixing force in the surface.

  Moreover, although the skull hole fixing barhole button 1 is made of calcium phosphate ceramics, any material may be used as long as it has biocompatibility. In particular, it is preferably composed of a β tricalcium phosphate porous body having bioabsorbability.

However, when it is composed of pure β-tricalcium phosphate porous material, since it is a brittle material, it is easy to break. For example, powder or granule of β-tricalcium phosphate porous material is made of polylactic acid, polyglycolic acid, etc. It is preferable to employ an elastic material having a certain degree of elasticity combined with the above absorbent polymer.
By doing in this way, even if the thickness dimension of the skull C fluctuates slightly due to individual differences among patients, the same skull valve fixing barhole button 1 can be used. In addition, since the skull C and the skull flap B are sandwiched in the thickness direction by the elastic force, the holding force can be increased by sandwiching the skull C and the skull flap B in a slightly elastically deformed state.

  In order to absorb individual differences among patients with the skull hole fixing barhole button 1 made of relatively hard calcium phosphate ceramics, a plurality of types of intervals between the end plate portions 3 and 4 are prepared, or end plate portions A spacer for adjusting the distance may be sandwiched between 3 and the skull C and the skull valve B.

1 is a perspective view showing a skull valve fixing bar hole button according to an embodiment of the present invention. FIG. It is a longitudinal cross-sectional view which shows the state which the skull hole fixation barhole button of FIG. 1 fixed the skull valve in the open head. It is a top view which shows the attachment procedure of the barhole button for skull valve fixation of FIG. It is a longitudinal cross-sectional view which shows the attachment procedure of FIG.

Explanation of symbols

C skull D drilling G wrench (tool)
DESCRIPTION OF SYMBOLS 1 Barhole button for skull flap fixation 2 Shaft part 3, 4 End plate part 3a, 4a End surface 5 Recessed part

Claims (6)

A skull hole fixing barhole button made of a biocompatible material that closes the perforation that occurs when the skull is opened,
A shaft portion that is inserted into the perforation, and a bowl-shaped end plate portion that is disposed at both ends of the shaft portion and is disposed at a position sandwiching the skull in the thickness direction,
One end plate part to be placed inside the skull is formed in a disc shape,
A skull valve fixing bar hole button in which the other end plate portion to be disposed outside the skull protrudes substantially to one side with respect to the center line of the shaft portion.   The skull valve fixing bar hole button according to claim 1, wherein an end plate portion to be disposed outside the skull is formed in a substantially semicircular shape.   The skull hole fixing bar hole button according to claim 1 or 2, wherein an end face in an axial direction of an end plate portion to be disposed inside the skull is formed in a substantially spherical shape.   A concave portion into which a predetermined tool for rotating around a center line of the shaft portion can be inserted is formed on an end surface in an axial direction of an end plate portion to be disposed outside the skull. Item 4. A skull hole fixing barhole button according to any one of Items 3 to 4.   The skull hole fixing barhole button according to any one of claims 1 to 4, which is made of a bioabsorbable material.   The skull hole fixing bar hole button according to claim 5, which is made of an elastic material.

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