JP5510875B1 - Extraction operation jig and medical screw using the extraction operation jig - Google Patents

Abstract

A medical screw is easily removed from a fractured site.
An outer cylinder portion 30 is inserted into the inner cylinder portion 20 from the outside, and the outer screw portion 24 is used in a state where the inner screw portion 31 is screwed, and the outer cylinder portion 30 is rotated clockwise. The outer screw portion 24 is screwed into the inner screw portion 31. When the outer cylinder portion 30 is screwed in, the lower end portion of the outer cylinder portion 30 descends downward while coming into contact with the outer side of the locking arm 22, and the locking arm 22 that has warped outwardly from the outer cylinder portion 30. It gradually disappears inward. When the extraction operation jig 10 is pushed toward the screw head from above, the locking claw 23 slides in accordance with the shape of the hemispherical head, and the guide portion is moved while bending the elastic locking arm 22 outward. Then, it is guided into the groove. When the locking claw 23 is pushed to the end, the locking claw 23 enters the locked portion which is a flat portion in the orthogonal direction from the groove on the back side of the head and is locked.
[Selection] Figure 2

Description

  The present invention relates to an extraction operation jig for extracting a medical screw for joining fracture sites, and a medical screw using the extraction operation jig.

  Patent Document 1 discloses a medical screw 1 having a hollow hole called a cannulated screw as shown in FIG. The screw 1 has been conventionally used for joining fracture sites in the medical field. A screw thread portion 1b is formed on the outer surface of the distal end portion 1a, and a conical blade 1c is formed at the foremost end thereof. An inner hole 1d is provided along the central axis. At the entrance of the inner hole 1d of the head 1e of the screw 1, there is provided, for example, a rotation operation portion 1f made of a hexagonal recess, and a tip end portion of a driver-like rotation operation jig is fitted into the rotation operation portion 1f. By rotating, the screw thread portion 1b is screwed into the bone to join the fracture site.

  In this conventional example, the screw 1 is screwed into the bone under the anesthesia, first, as shown in FIG. In contrast, it is inserted so as to be substantially orthogonal. The tip of the guide pin 2 is pointed like a cone, and punctures the skin A and the subcutaneous tissue B as they are and comes into contact with the bone cortical surface E of the bone C. I will screw it in.

  Next, the upper end of the guide pin 2 is inserted into the inner hole 1 d on the tip 1 a side of the screw 1, and the screw 1 is pushed in while being guided along the guide pin 2. The upper end of the guide pin 2 protruding further upward from the head 1 e of the screw 1 is inserted into the inner hole 3 b of the rotation operation jig 3. Subsequently, as shown in FIG. 15, after the screw 1 is pushed into the skin A and the subcutaneous tissue B by the rotation operation jig 3 and the tip 1 a of the screw 1 comes into contact with the bone cortex surface E, the rotation operation jig is used. 3 is rotated clockwise by manual operation by the gripping portion 3c. With the rotation of the screw 1, the screw thread portion 1b is screwed into the bone C along the guide pin 2 as shown in FIG.

  The rotation operation jig 3 is pulled out from the guide pin 2, and finally the guide pin 2 is pulled out from the bone C, the skin A and the like are sutured, and the joining process by the screw 1 of the fracture site D is completed.

JP 10-272142 A

  When several months have passed since the joining process, the fracture site D is healed, so the process of taking out the screw 1 that played the role is performed. After incising the skin A and the subcutaneous tissue B, the distal end portion 3a of the rotation operation jig 3 is fitted into the rotation operation portion 1f of the screw 1 and rotated counterclockwise, so that the screw screw portion 1b is screwed in. Loosen and remove from bone C.

  When the rotation operation jig 3 is properly fitted to the rotation operation portion 1 f and then rotated counterclockwise, the screw thread portion 1 b of the screw 1 comes out of the bone C. In this withdrawal, the screw 1 is lifted upward by the reaction force of the bone C until the screw screw portion 1b screwed into the bone C reaches the bone cortical surface E. However, the screw 1 still remains in the subcutaneous tissue B. If it is buried inside, the screw thread portion 1b will idle, making it difficult to pull out the screw 1.

  In addition, when several months have elapsed since the joining process, a rejection reaction to the metal occurs in the screwed bone C, and a gap may be formed between the bone C and the screw 1. In this case, even if the screw 1 is rotated, the screw thread portion 1b idles and it becomes difficult to pull out.

  Further, when the screw 1 is screwed at the time of joining the fracture site D and the screw 1 is detached from the bone C and screwed into the subcutaneous tissue B, the screw 1 is re-doed. Once the screw 1 needs to be extracted. At this time, even if the screw 1 is rotated in the counterclockwise direction, the screw thread portion 1b may idle, and the screw 1 may not be pulled out.

  When the screw 1 could not be pulled out, it was necessary to pull up the screw 1 using another means such as pliers while rotating the screw 1 with the rotation operation jig 3, and the removal process was difficult.

  The object of the present invention is to solve the above-mentioned problems, and to remove the medical screw from the bone easily and quickly after the bone has been healed or replaced, and a medical device using the removal operating jig. It is to provide a screw for use.

  In order to achieve the above object, a medical screw removal operation jig according to the present invention projects a plurality of rod-like locking arms having elasticity from a lower end portion of a cylindrical inner cylinder body downward. An inner cylinder part and a cylindrical outer cylinder part which is disposed outside the inner cylinder main body of the inner cylinder part and is shorter in length than the inner cylinder main body, and has a medical screw in an inner hole of the inner cylinder main body A medical screw removal operation jig in which a rotation operation jig can be inserted, and an outer screw portion is provided on the outer periphery of the inner cylinder body, and an inner screw portion is provided on the inner periphery below the outer cylinder portion The outer screw portion and the inner screw portion can be screwed together, and the locking arm is bent so as to bend outward toward the tip, and a locking claw bent inward at the foremost end of the locking arm. Provided, and the locking arm is pushed inward from the outside by rotation of the outer cylinder portion with respect to the inner cylinder body. Seen, engaged the head of the locking claws the medical screw, characterized in that it can pull up the medical screw.

Further, the medical screw according to the present invention is a medical screw used in an extraction operation jig having a locking arm provided with a locking claw that bends inward at the tip,
A groove that matches the arrangement of the locking arm is formed on the side of the head of the screw, a concave guide is formed at a location from the top of the head to the groove, and the lower end of the groove is The locked portion is formed in a substantially perpendicular direction over the back of the head.

  According to the extraction operation jig and the medical screw using the extraction operation jig according to the present invention, the medical screw in the case where it is not possible to rotate freely after the fracture site has been healed is provided on the head. It can be easily pulled out by locking the locking arm of the extraction operation jig to the locking portion.

  Further, even when the locking arm of the extraction jig is locked to the locked portion of the medical screw, the locked state can be easily released.

It is a perspective view of an extraction operation jig. It is a perspective view of the extraction operation jig of the state which screwed together the inner cylinder part and the outer cylinder part. It is a perspective view of a medical screw. It is a head expansion perspective view of a medical screw. It is a perspective view of a rotation operation jig. It is sectional drawing in the case of pushing in an extraction operation jig | tool from upper direction with respect to a medical screw. It is explanatory drawing of the state which latched the latching claw to the to-be-latched part. It is explanatory drawing at the time of releasing the latching state of a to-be-latched part and a latching claw. It is a perspective view of the extraction operation jig of Example 2. It is a perspective view of a rotation operation jig. It is a head expansion perspective view of a medical screw. It is explanatory drawing of the state which latched the latching claw to the to-be-latched part. It is a perspective sectional view of the conventional medical screw. It is explanatory drawing of the state which inserted the guide pin in the fracture site | part. It is explanatory drawing of the state which inserted the conventional medical screw in the subcutaneous tissue. It is explanatory drawing of the state which screwed in the conventional medical screw in the fracture site | part.

  The present invention will be described in detail based on the embodiment shown in FIGS.

  FIG. 1 is a perspective view of a medical screw removal operation jig, and FIG. 2 is a perspective view of a state in which an inner cylinder portion 20 and an outer cylinder portion 30 are screwed together. The extraction operation jig 10 is composed of an inner cylinder part 20 and an outer cylinder part 30, both of which are made of a metal material.

  The inner cylinder portion 20 is cylindrical and has a resiliency that extends in the circumferential direction of the inner cylinder body 21 having a length of about 20 cm and the lower end portion of the inner cylinder body 21, for example, every 90 ° and protrudes downward. And four locking arms 22 having. Each of these locking arms 22 is curved so as to bend outward frequently toward the tip, and a locking claw 23 having a hook portion that refracts in a substantially right-angle direction toward the inner side at the most distal end. Is formed. Moreover, the inner hole 25 of the inner cylinder main body 21 is circular in cross section.

  An outer thread portion 24 is engraved on the outer peripheral surface extending upward from the lower end portion of the inner cylinder main body 21 over a predetermined length D1. In the extraction operation jig 10 according to the first embodiment, the number of the locking arms 22 is four, but there is no problem even if a plurality of the locking arms 22 are appropriately formed, for example, three at every 120 °.

  The outer cylinder part 30 has a cylindrical shape with a length of about 10 cm shorter than the inner cylinder main body 21, and extends over a length D2 slightly longer than the length D1 of the outer screw part 24 on the inner peripheral surface directed upward from the lower end part. The internal thread portion 31 is engraved.

  As shown in FIG. 2, the removal operation jig 10 is used in a state in which the outer cylinder portion 30 is inserted into the inner cylinder portion 20 from the outside and the inner screw portion 31 is screwed into the outer screw portion 24. When the outer cylinder part 30 is inserted into the inner cylinder part 20 from above, the inner screw part 31 comes into contact with the outer screw part 24 and rotates the outer cylinder part 30 in the clockwise direction. Screwed together.

  In a state where the lower end portion of the outer cylinder portion 30 does not reach the lower end portion of the inner cylinder main body 21, the locking arm 22 is not restricted, so that it often warps outward as shown in FIG. It is curved. Further, when the outer cylinder part 30 is screwed in, the lower end part of the outer cylinder part 30 descends downward while coming into contact with the outer side of the locking arm 22, and the locking arm 22 that has warped outwardly becomes the outer cylinder part. It is gradually squeezed inward from 30.

  When the upper end of the outer screw portion 24 and the upper end of the inner screw portion 31 coincide with each other and the outer cylinder portion 30 cannot be screwed downward further, as shown in FIG. The surface is substantially parallel to the surface of the portion 30.

  FIG. 3 is a perspective view of the medical screw 40 used. The screw 40 is made of a metal material such as titanium, a right-hand screw screw portion 41 is formed on the outer surface of the tip portion, and a conical blade 42 is provided at the forefront thereof.

  In addition, the screw thread part 41 can also be provided not only in a front-end | tip part but in the outer surface of the whole longitudinal direction of the screw 40. FIG. Further, a through hole having a predetermined diameter may be provided along the central axis in order to insert the guide pin 2 and the guide pin for removal from the forefront to the head 43 of the screw 40 as necessary.

  As shown in the enlarged head perspective view of FIG. 4, the rear end of the screw 40 is a hemispherical head 43, and the tip of a rotating operation jig, which will be described later, is located at the center of the top surface of the head 43. For example, a rotation operation portion 44 is formed by a cross-shaped plus groove to be fitted. Further, four groove portions 45 that coincide with the arrangement of the locking arm 22 of the removal operation jig 10 are formed on the side portion of the head portion 43 every 90 ° with respect to the circumferential direction. A portion extending from the top portion to the groove portion 45 is a concave guide portion 46, and a lower end of the groove portion 45 is formed on the back surface of the head portion 43, and a locked portion 47 is formed in a substantially right angle direction.

  For the extraction process of the screw 40, an extraction operation jig 10 and a driver-like rotation operation jig 50 as shown in FIG. 5 are used. The tip 51 of the rotation operation jig 50 has a plus shape that matches the rotation operation unit 44 of the head 43, but the tip 51 may be matched to the shape of the rotation operation unit 44 of the screw 40. .

  When removing the screw 40, after incising the skin and subcutaneous tissue, the distal end portion 51 of the rotation operation jig 50 is fitted into the rotation operation portion 44 and rotated counterclockwise to the bone C of the screw 40. Loosen the screw. At this time, if there is no gap between the bone C and the screw 40 due to rejection or the like, the screw 40 can be pulled out of the body by rotating it counterclockwise.

  However, when a gap or the like is generated between the bone C and the screw 40, the rotation operation jig 50 is idled and the screw 40 cannot be extracted. In such a case, it is necessary to use the removal operation jig 10.

  In order to use the removal operation jig 10, as shown in FIG. 2, the shaft portion 52 is placed in the inner cylinder portion 20 of the removal operation jig 10 in a state where the inner cylinder portion 20 and the outer cylinder portion 30 are screwed together. Is inserted with a rotation operation jig 50 longer than the length of the inner cylinder portion 20. Then, the distal end portion 51 of the rotation operation jig 50 is protruded from the removal operation jig 10, and the distal end portion 51 is fitted into the rotation operation portion 44 of the screw 40.

  Next, when the extraction operation jig 10 is pushed into the head 43 of the screw 40 from above with the shaft section 52 in a state where the shaft section 52 of the rotation operation jig 50 is inserted into the extraction operation jig 10 as a guide, As shown in FIG. 6, the locking claw 23 slides in accordance with the shape of the hemispherical head 43, and is guided into the groove 45 through the guide portion 46 while bending the locking arm 22 having elasticity outward. When the locking claw 23 is pushed to the end, the locking claw 23 enters the locked portion 47 which is a flat portion in the orthogonal direction from the groove 45 on the back side of the head 43 as shown in FIG. . In this state, the locking arm 22 of the removal operation jig 10 is not caught by the head 43 of the screw 40 and is not removed.

  While the extraction claw 23 is locked to the locked portion 47 and the extraction operation jig 10 is pulled upward, the rotation operation jig 50 is rotated counterclockwise, and the screw 40 is pulled out of the body from the bone C. be able to. After the screw 40 is pulled out of the body, when the outer cylinder part 30 is turned counterclockwise with respect to the inner cylinder part 20 to raise the outer cylinder part 30, the locking arm 22 expands outward, as shown in FIG. The locking claw 23 can be removed from the screw 40.

  Further, as shown in FIG. 7, when the removal process of the screw 40 is stopped while the locking claw 23 is caught by the locked portion 47, the outer cylinder portion 30 is rotated counterclockwise with respect to the inner cylinder portion 20. Let it rise. By this rise, the locking arm 22 gradually expands outward, and the removal operation jig 10 can be similarly removed from the screw 40.

  FIG. 9 shows the extraction operation jig 10 ′ of the second embodiment. The inner hole 25 of the inner cylinder portion 20 of the first embodiment has a circular cross section, whereas the inner cylinder portion 20 ′ of the second embodiment has a regular hexagonal cross section. It is a square such as a square. A rotation operation jig 50 ′ having a rectangular column tip 51 ′ such as a regular hexagonal column shown in FIG. 10 is inserted into the inner hole 25 ′.

  FIG. 11 is an enlarged perspective view of the head of a medical screw 40 ′ using the extraction operation jig 10 ′. At the center of the top surface of the head 43, there is formed a rotation operation portion 44 'consisting of a hexagonal recess that fits into the tip 51' of the rotation operation jig 50 '. Although the cross section of the inner cylinder portion 20 ′ and the shape of the concave portion of the rotation operation portion 44 ′ of the second embodiment are regular hexagons, appropriate shapes such as regular polygons such as squares and regular pentagons, and star shapes may be used. .

  The shaft portion 52 of the rotation operation jig 50 according to the first embodiment can be freely rotated in the rotation direction with respect to the extraction operation jig 10, but as illustrated in FIG. 12, the extraction operation jig 10 according to the second embodiment. The 'shaft portion 52' and the rotation operation jig 50 'rotate together to perform the removal operation after insertion.

  Therefore, the rotation operation in the second embodiment holds only the rotation operation jig 50 ′ as compared with the first embodiment in which the rotation operation jig 50 must be rotated while holding the extraction operation jig 10 at the time of extraction. Therefore, the screw 40 ′ can be easily removed.

  Further, since the shaft portion 52 ′ and the rotation operation jig 50 ′ of the removal operation jig 10 ′ are integrated after insertion, the tip 51 ′ of the rotation operation jig 50 ′ is fitted into the rotation operation section 44 ′. After the joining, the locking arm 22 whose rotational direction is fixed is naturally guided into the groove 45 of the screw 40 ′ simply by lowering the extraction operation jig 10 ′ downward.

  Moreover, although the groove part 45 was provided in screw 40, 40 'of Example 1, 2, if the corner | angular part was formed in the substantially right angle direction toward the back surface of the head 43 like the to-be-latched part 47, There is no need to provide the groove 45.

  In the case of the screws 40 and 40 ′ having the groove portions of the first and second embodiments, when the locking arm 22 is locked in the groove portion 45, the removal operation jigs 10 and 10 ′ and the screws 40 and 40 ′ are integrated in the rotation direction. However, in the case of the screws 40 and 40 ′ in which the groove 45 is not provided and the above-described locked portion 47 is provided on the entire lower end of the head 43, the screw 40 and 40 ′ Thus, the removal operation jigs 10, 10 ′ can slide in the rotation direction.

However, even if the screws 40 and 40 ′ are not provided with the groove 45, it is possible to apply a force in the pulling direction, so that the extraction operation jigs 10 and 10 are rotated while being rotated by the rotation operation jigs 50 and 50 ′. By using ', the idling screws 40, 40' can be removed.

DESCRIPTION OF SYMBOLS 10, 10 'Removal operation jig 20 Inner cylinder part 21 Inner cylinder main body 22 Locking arm 23 Locking claw 24 Outer thread part 25 Inner hole 30 Outer cylinder part 31 Inner thread part 40, 40' Medical screw 41 Screw thread part 42 Conical blade 43 Head 44 Rotation operation part 45 Groove part 46 Guide part 47 Locked part 50, 50 'Rotation operation jig

Claims (7)

A plurality of rod-like locking arms having elasticity from the lower end of the cylindrical inner cylinder main body are arranged to project downward, and are arranged outside the inner cylinder main body of the inner cylinder, A medical screw removal operation jig comprising a cylindrical outer tube portion having a length shorter than that of the tube main body, wherein a rotation operation jig for the medical screw can be inserted into an inner hole of the inner tube main body. ,
An outer screw portion is provided on the outer periphery of the inner cylinder body, an inner screw portion is provided on an inner periphery below the outer cylinder portion, and the outer screw portion and the inner screw portion can be screwed together. A locking claw bent inwardly at the foremost end of the locking arm, and the locking arm is moved from the outside to the inside by rotation of the outer cylinder portion relative to the inner cylinder body. A medical screw removal operation jig, wherein the medical screw can be pulled up and the medical claw can be pulled up by locking the head of the medical screw.   The said latching arm which the lower end part of the said outer cylinder part was curving outside when the said outer cylinder part was screwed in to a content main body will gradually squeeze inside. Medical screw extraction jig.   The length of the internal thread part of the said external cylinder part was made longer than the length of the external thread part of the said internal cylinder main body, The extraction operation jig of the medical screw of Claim 1 or 2 characterized by the above-mentioned.   The medical screw extraction operation jig according to any one of claims 1 to 3, wherein the plurality of locking arms are arranged at an equal angle on an outer periphery of a lower end of the inner cylinder main body.   The inner hole of the inner cylinder main body has a regular polygonal cross section, the shaft portion of the rotation operation jig has a regular polygonal cross section, and the medical screw is rotated by a distal end portion of the rotation operation jig. The medical screw extraction operation jig according to any one of claims 1 to 4. A medical screw used in an extraction operation jig having a locking arm provided with a locking claw bent inward at the tip,
A groove that matches the arrangement of the locking arm is formed on the side of the head of the screw, a concave guide is formed at a location from the top of the head to the groove, and the lower end of the groove is A medical screw characterized in that a locked portion is formed in a substantially perpendicular direction over the back of the head. The medical screw according to claim 6, wherein a plurality of the groove portions are arranged at an equal angle on an outer periphery of the head.

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