CN211094478U

CN211094478U - Guiding device

Info

Publication number: CN211094478U
Application number: CN201921124380.4U
Authority: CN
Inventors: 孙延东; 李健; 胡方遒; 翁资欣
Original assignee: Suzhou Microport Orthorecon Co Ltd
Current assignee: Suzhou Microport Orthorecon Co Ltd
Priority date: 2019-07-17
Filing date: 2019-07-17
Publication date: 2020-07-28
Anticipated expiration: 2029-07-17

Abstract

The utility model relates to a guiding device. The guide device comprises a main body, a first rotating piece and a second rotating piece. Wherein, first rotating member rotationally sets up the one end at the main part, and first rotating member detachable connection has first drill bushing. The second rotating piece is rotatably arranged at the other end of the main body, and the second rotating piece is detachably connected with a second drill bushing. The guiding device can use drill bits with various specifications and diameters, saves the time for replacing the drill bushing before operation, simplifies the types of surgical instruments, and reduces the possibility of surgical accidents caused by the fact that a doctor selects the surgical instruments by mistake.

Description

Guiding device

Technical Field

The utility model relates to a total hip joint replacement art field especially relates to a guider.

Background

The total hip joint replacement is one of the effective treatment operations for treating serious hip joint diseases, and the operation mode is that a prosthesis similar to the hip joint of a human body is made of metal materials with good biocompatibility and mechanical property so as to replace the hip joint surface damaged by diseases or injuries, thereby achieving the purposes of recovering the functions of the hip joint and relieving pain. In total hip replacement surgery, after the acetabular cup prosthesis is implanted into a human body, the acetabular cup prosthesis needs to be fixed to an acetabulum by matching with screws. Specifically, an acetabular cup prosthesis screw hole coaxial with the acetabular cup prosthesis screw hole needs to be drilled in the acetabulum of the human body, and then the screw needs to be screwed in so as to fix the acetabular cup prosthesis to the acetabulum. In order to ensure that the acetabular screw hole is coaxial with the acetabular cup prosthesis screw hole, a guide is required to guide the drill.

Generally, for drill bits with different diameters, the guide devices with different specifications need to be replaced for drilling and guiding, so that the preoperative preparation time is increased. Particularly, when there are a plurality of holes for the acetabular screw holes, it is necessary to prepare guides of various specifications, which increases the variety of surgical instruments and is likely to cause postoperative complications of patients due to the misselection of surgical instruments by doctors.

SUMMERY OF THE UTILITY MODEL

Based on this, it is necessary to provide a guiding device for reducing the preparation time before operation and simplifying the variety of surgical instruments.

A guide device, comprising:

A main body;

The first rotating piece is rotatably arranged at one end of the main body and is detachably connected with a first drill bushing; and the number of the first and second groups,

The second rotating piece is rotatably arranged at the other end of the main body and is detachably connected with a second drill bushing.

In one embodiment, the main body is provided with a cavity penetrating through both ends, and the guide device further comprises:

The first limiting piece is movably arranged in the cavity and can be connected with or separated from the first rotating piece; and the number of the first and second groups,

And the second limiting part is movably arranged in the cavity and can be connected with or separated from the second rotating part.

In one embodiment, the first rotating member is provided with a first latch, the first limiting member is provided with a first boss, and the first boss can be engaged with or separated from the first latch so as to limit the angle of the first drill sleeve; and/or the presence of a gas in the gas,

The second rotating part is provided with a second latch, the second limiting part is provided with a second boss, and the second boss can be meshed with or separated from the second latch so as to limit the angle of the second drill bushing.

In one embodiment, the guiding device further includes an elastic member disposed in the cavity, and two ends of the elastic member are respectively abutted against or fixedly connected to the first limiting member and the second limiting member.

In one embodiment, the first limiting member is provided with a first waist-shaped hole, the main body is provided with a second waist-shaped hole, the first waist-shaped hole is communicated with the second waist-shaped hole, the length of the first waist-shaped hole is smaller than that of the second waist-shaped hole, and a first limiting shaft penetrates through the first waist-shaped hole and the second waist-shaped hole; and/or the presence of a gas in the gas,

The second locating part is provided with a third waist-shaped hole, the main body is provided with a fourth waist-shaped hole, the third waist-shaped hole is communicated with the fourth waist-shaped hole, the length of the third waist-shaped hole is smaller than that of the fourth waist-shaped hole, and a second locating shaft penetrates through the third waist-shaped hole and the fourth waist-shaped hole.

In one embodiment, the second waist-shaped hole and the fourth waist-shaped hole are symmetrically arranged relative to the elastic member.

In one embodiment, the guiding device further comprises a handle, the handle is movably sleeved outside the main body, and the handle is connected with the first limiting shaft and the second limiting shaft.

In one embodiment, the outer wall of the main body is further provided with a first holding surface and a second holding surface, and the first holding surface and the second holding surface are respectively located on two sides of the handle.

In one embodiment, the first rotating member is provided with a first threaded hole, and the first drill sleeve is in threaded fit with the first threaded hole; and/or the presence of a gas in the gas,

The second rotating piece is provided with a second threaded hole, and the second drill bushing is in threaded fit with the second threaded hole.

In one embodiment, the first rotating member is provided with a first limiting hole, one end of the main body close to the first rotating member is provided with a first limiting pin, and the first limiting pin is arranged in the first limiting hole in a penetrating manner; and/or the presence of a gas in the gas,

The second rotating piece is provided with a second limiting hole, a second limiting pin is arranged at one end, close to the second rotating piece, of the main body, and the second limiting pin penetrates through the second limiting hole.

In one embodiment, a first mounting groove and a second mounting groove are respectively formed at two ends of the main body, and the first rotating member is rotatably arranged in the first mounting groove through a first rotating member; the second rotating piece is rotatably arranged in the second mounting groove through a second adapter piece.

Above-mentioned guider rotationally sets up first rotating member and second rotating member respectively through the both ends at the main part, and first rotating member is provided with first drill bushing, and the second rotating member is provided with the second drill bushing, and first drill bushing and second drill bushing all can be used to lead to the drill bit to can realize leading the drill bit of two kinds of diameters through a guider, change the drill bushing required time before having saved. Furthermore, the first drill bushing is detachably connected with the first rotating part, and the second drill bushing is also detachably connected with the second adaptor part, so that the purpose that one set of guide device can be suitable for drill bits with various diameter specifications can be realized by replacing the first drill bushing and the second drill bushing with different specifications, the types of surgical instruments are simplified, and the possibility of surgical accidents caused by the fact that a doctor selects the surgical instruments by mistake is reduced. Meanwhile, the guide device is connected with or separated from the first rotating part and the second rotating part through the first limiting part and the second limiting part respectively, so that the angle of the first drill bushing and the angle of the second drill bushing can be limited, the first drill bushing and the second drill bushing are ensured to be coaxial with an acetabulum threaded hole, the operation effect is ensured, and postoperative complications of a patient are avoided.

Drawings

FIG. 1 is a schematic view of an embodiment of a guide device;

FIG. 2 is a structural cross-sectional view of the guide shown in FIG. 1;

Fig. 3 is a broken-away view of the guide shown in fig. 1.

Description of reference numerals:

100. A guide device; 110. a main body; 111. a cavity; 112. a first mounting groove; 113. a second mounting groove; 114. a second kidney-shaped hole; 115. a fourth kidney-shaped hole; 116. a first holding surface; 117. a second holding surface; 120. a first rotating member; 121. a first threaded hole; 122. a first latch; 123. a first limit hole; 124. a first limit pin; 125. a first transfer member; 130. a first drill bushing; 131. a first guide hole; 140. a second rotating member; 141. a second threaded hole; 142. a second latch; 143. a second limiting hole; 144. a second limit pin; 145. a second adaptor; 150. a second drill bushing; 151. a second guide hole; 160. a first limit piece; 161. a first boss; 162. a first kidney-shaped hole; 163. a first limit shaft; 170. a second limiting member; 171. a second boss; 172. a third kidney-shaped hole; 173. a second limit shaft; 180. an elastic member; 190. a handle.

Detailed Description

In order to make the above objects, features and advantages of the present invention more comprehensible, embodiments of the present invention are described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The present invention can be embodied in many different forms other than those specifically described herein, and it will be apparent to those skilled in the art that similar modifications can be made without departing from the spirit and scope of the invention, and it is therefore not to be limited to the specific embodiments disclosed below.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," "up," "down," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

In the present invention, the terms "first" and "second" do not denote any particular quantity or order, but are merely used to distinguish names.

Referring to fig. 1-2, embodiments of the present application provide a guide 100 for guiding a drill bit in a total hip arthroplasty. Specifically, the guiding device 100 of an embodiment includes a main body 110, a first rotating member 120, a first limiting member 160, a second rotating member 140, and a second limiting member 170. The main body 110 is a cylindrical rod, and a cylindrical cavity 111 penetrating through both ends of the main body 110 is formed in the main body 110.

The first and second

rotating members

120 and 140 are rotatably provided at both ends of the body 110, respectively. Wherein the first rotating member 120 is detachably connected with a first drill bushing 130, the first drill bushing 130 is provided with a first guiding hole 131, and the first guiding hole 131 is used for guiding a drill bit. Further, the first drill bushing 130 may have various specifications, and the first guide hole 131 of the first drill bushing 130 having different specifications has different hole diameters, so that drill bits having different specifications can be guided. The angle of the first drill sleeve 130 can be adjusted by the rotatable first rotation member 120 to ensure that the first guide hole 131 is coaxial with the acetabular cup screw hole. Further, the first retaining member 160 is movably disposed in the cavity 111 of the main body 110, and the first retaining member 160 can be connected to or separated from the first rotating member 120 to define an angle of the first drill bushing 130. Specifically, the first limiting member 160 can move axially (in the up-down direction in fig. 1-2) along the cavity 111, the first limiting member 160 has a connection state connected to the first rotating member 120 and a disconnection state disconnected from the second rotating member 140, and when in the connection state, the first rotating member 120 is locked by the first limiting member 160, that is, the first rotating member 120 cannot rotate relative to the main body 110, and at this time, the angle of the first drill sleeve 130 is locked. When the angle of the first drill bushing 130 needs to be adjusted, the first limiting member 160 is changed from the connection state to the disconnection state by moving the first limiting member 160, so that the first limiting member 160 is unlocked, and at this time, the first rotating member 120 can rotate relative to the main body 110 to adjust the angle of the first drill bushing 130.

Similarly, a second drill sleeve 150 is detachably connected to the second rotary member 140, and the second drill sleeve 150 is provided with a second guide hole 151, and the second guide hole 151 is used for guiding the drill bit. Further, the second drill sleeve 150 may have a plurality of specifications, and the second guide holes 151 of the second drill sleeve 150 having different specifications have different diameters, so that drill bits having different specifications can be guided. The angle of the second drill sleeve 150 can be adjusted by the rotatable second rotation member 140 to ensure that the second guide hole 151 is coaxial with the acetabular cup screw hole. Further, a second retaining member 170 is movably disposed in the cavity 111 of the main body 110, and the second retaining member 170 can be connected to or separated from the second rotating member 140 to define the angle of the second drill sleeve 150. Specifically, the second limiting member 170 can move along the cavity 111, the second limiting member 170 has a connection state connected to the second rotating member 140 and a separation state separated from the second rotating member 140, and when the second limiting member 170 is in the connection state, the second rotating member 140 is locked by the second limiting member 170, that is, the second rotating member 140 cannot rotate relative to the main body 110, and at this time, the angle of the second drill sleeve 150 is locked. When the angle of the second drill bushing 150 needs to be adjusted, the second limiting member 170 is changed to the separated state by moving the second limiting member 170, so that the second limiting member 170 is unlocked, and at this time, the second rotating member 140 can rotate relative to the main body 110 to adjust the angle of the second drill bushing 150.

The guide device 100 is provided with the first rotating part 120 and the second rotating part 140 at two ends of the main body 110 in a rotatable manner, the first rotating part 120 is provided with the first drill bushing 130, the second rotating part 140 is provided with the second drill bushing 150, and both the first drill bushing 130 and the second drill bushing 150 can be used for guiding the drill bits, so that the drill bits with at least two diameters can be guided through one guide device 100, the time for replacing the drill bushings before the operation is saved, and the number of surgical instruments is reduced. Further, the first drill bushing 130 is detachably connected with the first rotating member 120, and the second drill bushing 150 is detachably connected with the second rotating member 140, so that the purpose that the guide device 100 can be suitable for drill bits with various diameter specifications can be achieved by replacing the first drill bushing 130 and the second drill bushing 150 with different specifications, the types of surgical instruments are simplified, and the possibility of surgical accidents caused by the fact that a doctor selects the surgical instruments by mistake is reduced. Meanwhile, the guide device 100 is connected to or separated from the first rotating member 120 and the second rotating member 140 through the first limiting member 160 and the second limiting member 170, so that the angle of the first drill bushing 130 and the angle of the second drill bushing 150 can be adjusted, the first drill bushing 130 and the second drill bushing 150 can be coaxial with the acetabulum threaded hole, the surgical effect is ensured, and postoperative complications of a patient are avoided.

Referring to fig. 1 and 2, a first mounting groove 112 and a second mounting groove 113 are respectively formed at both ends of the main body 110, and specifically, both the first mounting groove 112 and the second mounting groove 113 may be U-shaped grooves. The first rotating member 120 is rotatably disposed in the first mounting groove 112 by the first rotating member 125. The second rotating member 140 is rotatably disposed in the second mounting groove 113 by a second adaptor 145. The first adapter 125 and the second adapter 145 may be, for example, pins or other known rotatably coupled positioning elements. The first rotating member 120 and the second rotating member 140 are respectively disposed in the first mounting groove 112 and the second mounting groove 113, so that the first rotating member 120 and the second rotating member 140 are prevented from colliding or interfering with other parts or external objects during the rotation process, and the rotation stability of the first rotating member 120 and the second rotating member 140 is ensured.

Referring to fig. 2, in one embodiment, the first rotating member 120 is provided with a first latch 122, and specifically, the first latch 122 is distributed in an arc shape with the first rotating member 125 as an axis. One end of the first limiting member 160 close to the first rotating member 120 is provided with a first boss 161, and the first boss 161 can be engaged with or disengaged from the first latch 122, so as to lock or release the first rotating member 120, thereby limiting the angle of the first drill sleeve 130. Similarly, the second rotating member 140 is provided with a second latch 142, and the second latch 142 is distributed in an arc shape with the second adaptor 145 as an axis. One end of the second limiting member 170, which is close to the second rotating member 140, is provided with a second boss 171, and the second boss 171 can be engaged with or disengaged from the second latch 142, so as to lock or release the second rotating member 140, thereby limiting the angle of the second drill sleeve 150.

Further, the first rotating member 120 is provided with a first threaded hole 121, and the first drill bushing 130 is threadedly engaged with the first threaded hole 121. The first drill bushing 130 is detachably connected with the first threaded hole 121 through threads, so that the first drill bushing 130 with different specifications can be conveniently installed or replaced. Further, by removing the first drill bushing 130, the first threaded hole 121 can also be used as a guide hole to guide a drill, further increasing the variety of applicable drills of the guide device 100. Similarly, the second rotating member 140 is provided with a second threaded hole 141, and the second drill bushing 150 is threadedly engaged with the second threaded hole 141. The second drill bushing 150 is detachably connected with the second threaded hole 141 through threads, so that the second drill bushing 150 with different specifications can be conveniently installed or replaced. Further, by removing the second drill bushing 150, the second threaded hole 141 can also be used as a guide hole to guide a drill, thereby further increasing the variety of applicable drills of the guide device 100.

Further, the first rotating member 120 is provided with a first limiting hole 123, specifically, the first limiting hole 123 is a circular hole or an arc-shaped hole with the first rotating member 125 as an axis. One end of the main body 110 close to the first rotating member 120 is provided with a first limit pin 124, and the first limit pin 124 is disposed in the first limit hole 123 in a penetrating manner, so that the rotation range of the first rotating member 120 can be limited in the range limited by the first limit pin 124 and the first limit hole 123 through the cooperation of the first limit pin 124 and the first limit hole 123, and the problem that the first latch 122 and the first boss 161 cannot be meshed due to the overlarge rotation angle of the first rotating member 120 is avoided. Similarly, the second rotating member 140 is provided with a second limiting hole 143, specifically, the second limiting hole 143 is a circular hole or an arc-shaped hole with the second adaptor 145 as an axis. One end of the main body 110 close to the second rotating member 140 is provided with a second limit pin 144, and the second limit pin 144 penetrates through the second limit hole 143, so that the rotation range of the second rotating member 140 can be limited within the range limited by the second limit pin 144 and the second limit hole 143 through the cooperation of the second limit pin 144 and the second limit hole 143, and the problem that the second latch 142 and the second boss 171 cannot be meshed due to the overlarge rotation angle of the second rotating member 140 is avoided.

Referring to fig. 2 and 3, in one embodiment, the guiding device 100 further includes an elastic member 180, the elastic member 180 is disposed in the cavity 111 of the main body 110, and two ends of the elastic member 180 are respectively abutted against or fixedly connected to the first limiting member 160 and the second limiting member 170. Specifically, the elastic member 180 may be a spring, when the first limiting member 160 and the second limiting member 170 are in the connection state, the elastic member 180 is in a compressed state, and the elastic member 180 can apply a pushing force to the first limiting member 160 and the second limiting member 170 to keep the first limiting member 160 and the second limiting member 170 in the connection state.

Further, the first limiting member 160 is provided with a first kidney-shaped hole 162, the main body 110 is provided with a second kidney-shaped hole 114, the first kidney-shaped hole 162 is communicated with the second kidney-shaped hole 114, and the length of the first kidney-shaped hole 162 is smaller than that of the second kidney-shaped hole 114. The length of the first kidney-shaped hole 162 refers to the length of the first kidney-shaped hole 162 in the axial direction of the first stopper 160. The length of the second kidney-shaped hole 114 refers to the length of the second kidney-shaped hole 114 in the axial direction of the body 110. Further, a first limiting shaft 163 penetrates through the first waist-shaped hole 162 and the second waist-shaped hole 114, so that the first limiting member 160 can be driven to move in the cavity 111 by moving the first limiting shaft 163, and the first limiting member 160 is connected to or separated from the first connecting member 125. Similarly, the second limiting member 170 is provided with a third waist-shaped hole 172, the main body 110 is provided with a fourth waist-shaped hole 115, the third waist-shaped hole 172 communicates with the fourth waist-shaped hole 115, and the length of the third waist-shaped hole 172 is smaller than that of the fourth waist-shaped hole 115. The length of the third kidney-shaped hole 172 refers to the axial length of the third kidney-shaped hole 172 on the second stopper 170. The length of the fourth kidney-shaped hole 115 refers to the length of the fourth kidney-shaped hole 115 in the axial direction of the body 110. Further, a second limiting shaft 173 penetrates through the third kidney-shaped hole 172 and the fourth kidney-shaped hole 115, so that the second limiting member 170 can be driven to move in the cavity 111 by moving the second limiting shaft 173, and the second limiting member 170 is connected to or separated from the second adaptor 145. Further, the second waist-shaped hole 114 and the fourth waist-shaped hole 115 are symmetrically arranged with respect to the position of the elastic member 180.

Further, the guiding device 100 further includes a handle 180, the handle 180 is movably disposed outside the main body 110, and the handle 180 is connected to the first limiting shaft 163 and the second limiting shaft 173, so that the handle 180 can adjust the angles of the first drill sleeve 130 and the second drill sleeve 150 more conveniently. Specifically, for example, when the angle of the first drill sleeve 130 is adjusted, the handle 180 is pulled downward, so that the first limiting shaft 163 drives the first limiting member 160 to move downward along the cavity 111, the elastic member 180 is further compressed, and the first boss 161 is separated from the first latch 122, at this time, the first rotating member 120 can rotate a certain angle within the limit range of the first limiting pin 124 and the first limiting hole 123, so as to change the angle of the first drill sleeve 130. Meanwhile, the second limiting member 170 keeps the second boss 171 engaged with the second latch 142 under the thrust of the elastic member 180, and at this time, the second rotating member 140 cannot rotate. Further, the length of the third kidney-shaped hole 172 is greater than the depth of the first latch 122, so that the second limiting shaft 173 does not touch the lower end of the third kidney-shaped hole 172 when the handle 180 is pulled downward to withdraw the first boss 161 from the first latch 122. That is, a sufficient downward movement space of the first limiting member 160 is ensured, and the situation that the handle 180 is pulled to the bottom and the first boss 161 is not separated from the first latch 122 is avoided. Similarly, the length of the first kidney-shaped hole 162 is greater than the depth of the second latch 142, so that the first and second

rotating members

120 and 140 can work smoothly. Further, after the handle 180 is released, the first limiting member 160 and the second limiting member 170 are respectively connected to the first rotating member 120 and the second rotating member 140 under the pushing force of the elastic member 180, so as to ensure that the first rotating member 120 and the second rotating member 140 can not rotate any more.

Further, referring to fig. 1, the outer wall of the main body 110 is further provided with a first holding surface 116 and a second holding surface 117, and the first holding surface 116 and the second holding surface 117 are respectively located at two sides of the handle 180 and are symmetrical with respect to the position of the handle 180. Further, the first holding surface 116 and the second holding surface 117 are both flat surfaces, thereby facilitating the holding operation during the operation.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only represent some embodiments of the present invention, and the description thereof is specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. A guide device, comprising:

A main body;

2. The guide device of claim 1, wherein the body is provided with a cavity extending through both ends; the guide device further comprises:

3. The guide device of claim 2, wherein:

The first rotating piece is provided with a first latch, the first limiting piece is provided with a first boss, and the first boss can be meshed with or separated from the first latch so as to limit the angle of the first drill bushing; and/or the presence of a gas in the gas,

4. The guide device of claim 2, wherein:

The guiding device further comprises an elastic piece, the elastic piece is arranged in the cavity, and two ends of the elastic piece are respectively abutted against or fixedly connected with the first limiting piece and the second limiting piece.

5. The guide device of claim 4, wherein:

The first limiting piece is provided with a first waist-shaped hole, the main body is provided with a second waist-shaped hole, the first waist-shaped hole is communicated with the second waist-shaped hole, the length of the first waist-shaped hole is smaller than that of the second waist-shaped hole, and a first limiting shaft penetrates through the first waist-shaped hole and the second waist-shaped hole; and/or the presence of a gas in the gas,

6. The guide device of claim 5, wherein:

The guide device further comprises a handle, the handle is movably sleeved outside the main body, and the handle is connected with the first limiting shaft and the second limiting shaft.

7. The guide device of claim 6, wherein:

The outer wall of the main body is further provided with a first holding surface and a second holding surface, and the first holding surface and the second holding surface are respectively located on two sides of the handle.

8. The guide device of claim 1, wherein:

The first rotating piece is provided with a first threaded hole, and the first drill bushing is in threaded fit with the first threaded hole; and/or the presence of a gas in the gas,

9. The guide device of claim 1, wherein:

The first rotating piece is provided with a first limiting hole, one end of the main body, which is close to the first rotating piece, is provided with a first limiting pin, and the first limiting pin is fixedly arranged in the first limiting hole in a penetrating manner; and/or the presence of a gas in the gas,

The second rotating piece is provided with a second limiting hole, a second limiting pin is arranged at one end, close to the second rotating piece, of the main body, and the second limiting pin penetrates through the second limiting hole to be fixed.

10. The guide device of claim 1, wherein:

The two ends of the main body are respectively provided with a first mounting groove and a second mounting groove, and the first rotating piece is rotatably arranged in the first mounting groove through a first rotating piece; the second rotating piece is rotatably arranged in the second mounting groove through a second adapter piece.