JP6312978B2 - Artificial joint components - Google Patents

Description

  The present invention relates to an artificial joint component to which a ball-shaped component slides or a liner on which a ball-shaped component slides is attached.

  Conventionally, artificial joint replacement for replacing a part or all of a joint with an artificial joint is performed on a patient with an abnormality in the joint. An artificial hip joint or an artificial shoulder joint as an artificial joint includes a ball-shaped component, a stem-shaped component to which the ball-shaped component is fixed or integrally provided, and a component for an artificial joint having a shell-shaped main body portion. It is prepared for. Further, the shell-like main body portion in the above-described artificial joint component is provided with a curved concave surface on which a ball-shaped component slides or a liner on which the ball-shaped component slides is attached.

  In Patent Document 1, an artificial hip joint socket having a double socket structure in which a ball-shaped component slides is disclosed. The artificial hip joint socket has an outer socket made of a titanium deep-drawn thin plate and an inner socket made of hardened polymer polyethylene. The inner socket is provided as a liner on which the ball-shaped component slides. The inner socket, which is a liner, is attached to the outer socket.

  The artificial hip joint socket is further provided with an anchor pin that is provided as a turning part made of titanium and is attached to the outer socket so as to protrude outward from the outer socket. The anchor pin is provided as a separate part from the outer socket. The anchor pin is fixed to the outer socket by rivet bonding. Further, the end of the anchor pin protruding from the outer socket is formed in a hemispherical curved surface. Further, a notch groove is provided on the outer periphery of the anchor pin for facilitating attachment to the bone.

  In Patent Document 1, in paragraph 0009, it is also possible to provide a pre-deformed metal woven material “mesh” in the range of, for example, an anchor pin on the outer socket in order to firmly fix bone tissue. The effect is described.

JP-A-10-323360

  As described above, the outer socket of the artificial hip joint socket disclosed in Patent Document 1 and the anchor pin for satisfactorily fixing to the bone are provided as separate members. For this reason, the artificial joint component composed of the outer socket and the anchor pin described above has an anchor pin and an outer portion formed by rivet bonding when a lateral pressure, which is a pressure acting from the side of the anchor pin, is repeatedly applied. There is a risk that damage is likely to occur at the joint with the socket. Therefore, this artificial joint component may easily increase the risk of breakage.

  Furthermore, in the artificial joint component (outer socket and anchor pin) in the artificial hip joint socket of Patent Document 1, a notch groove for attaching to a bone is provided in the anchor pin. For this reason, when the above-mentioned side pressure is repeatedly applied to the anchor pin, the artificial joint component is likely to be damaged in the notch groove due to the stress concentration, and the risk of breakage may be easily increased.

  Patent Document 1 describes that a metal fabric mesh can be attached to the anchor pin of the artificial joint component. However, when the above-described lateral pressure repeatedly acts on the anchor pin, there is a risk that damage is likely to occur at the joint between the metal fabric mesh and the anchor pin. Therefore, this artificial joint component may easily increase the risk of breakage.

  Further, in the above-described artificial joint component disclosed in Patent Document 1, the outer socket is formed of a titanium deep-drawn thin plate. For this reason, hip replacement is performed, and when the artificial joint component is fixed to the pelvis with the acetabulum, the smooth surface of the outer socket and the acetabulum of the pelvis are Depending on the friction, it is difficult to ensure sufficient fixing performance to obtain a fixing force to the bone.

  Further, the artificial joint component disclosed in Patent Document 1 is provided with an anchor pin in which a notch portion is formed in order to obtain a fixing force to the bone. However, the end of the anchor pin on the tip side is formed in a hemispherical curved shape. For this reason, when the above-mentioned artificial joint component is fixed to the pelvis, it is difficult to ensure sufficient fixing performance for obtaining a fixing force with respect to the bone depending on a portion other than the notch portion of the anchor pin. In particular, it is difficult to ensure sufficient fixation performance in an initial state in which hip replacement is performed and the above-described artificial joint component is fixed to the pelvis.

  In view of the above circumstances, the present invention realizes a structure in which damage is unlikely to occur, can reduce the risk of breakage, and can improve the fixing performance for obtaining a fixing force to the bone. The purpose is to provide.

In order to achieve the above object, an artificial joint component according to an aspect of the present invention is provided with a curved concave surface on which a ball-shaped component slides or a liner on which the ball-shaped component slides is attached. The present invention relates to an artificial joint component having a shell-like body portion. An artificial joint component according to an aspect of the present invention is an inner portion that is an inner portion of the main body portion that is the recessed surface side, and at least includes a portion on which the ball-shaped component slides or the liner is attached. A structure portion and an outer structure portion provided outside the inner structure portion, the inner structure portion is configured as a dense body, and the outer structure portion is sparser than the dense body of the inner structure portion. It has a porous part constituted as a porous body which is a structure, and the inner structure part and the outer structure part are integrally formed.

  According to this structure, the inner structure part comprised as a dense body and the outer structure part which has a porous part are integrally molded. For this reason, there is no junction between the inner structure part and the outer structure part, and stress concentration is difficult to occur, and it is possible to realize a structure in which damage is not easily caused even when repeated stress is applied. it can. Thereby, the risk of breakage can be reduced. And according to said structure, since a porous part is provided in an outer structure part, a big frictional force can be ensured between bones, the fixation performance for obtaining the fixation force to a bone is improved, and sufficient fixation performance is obtained. Can be secured. Furthermore, since the outer structure portion is provided with the porous portion, in the long term, the bone grows so as to enter the pores of the porous portion. Thereby, it is easy to promote the fusion with the bone, and the long-term fixing performance to the bone can be improved.

  Therefore, according to said structure, the component for artificial joints which can implement | achieve the structure which does not produce damage easily, can reduce the risk of breakage, and can improve the fixation performance for obtaining the fixation force with respect to a bone is provided. be able to.

Artificial joints for components according to an aspect of the present invention, the previous SL said outer structural portion and the inner structural portion, in a state in which metal powder having biocompatibility is integrated by being melted once are sequentially stacked Preferably it is formed.

  According to this configuration, the inner structure portion and the outer structure portion are formed in an integrated state by sequentially laminating and once melting the metal powder. That is, the inner structure portion and the outer structure portion are integrally formed by a metal powder additive manufacturing method. For this reason, it is not necessary to perform a complicated cutting process etc. with respect to a metal and to form the component for artificial joints which has a porous part. Further, even a difficult-to-cut material such as a titanium alloy that is widely distributed as a material for medical instruments can be easily formed as a component for an artificial joint because it does not require cutting with a complicated shape. Therefore, the component for artificial joints provided with the inner structure part comprised as a dense body and the outer structure part which has a porous part can be easily integrally formed.

Artificial joints for components according to an aspect of the present invention, prior Symbol porous portion is preferably provided over the entire outer peripheral surface of the portion included in the body portion in the outer structural portion.

  According to this configuration, since the porous portion is provided on the entire outer peripheral surface of the outer structure portion in the main body portion, it is possible to secure a larger frictional force with the bone and further improve the fixing performance with respect to the bone. Moreover, since the area | region where long-term union with a bone is accelerated | stimulated increases, the long-term fixation performance with respect to a bone can further be improved.

Artificial joints for components according to an aspect of the present invention, the portion included in the body portion in the front Kisotogawa structure section, the pores of the porous portion from the inner portion adjacent to the inner structural portion to portion of the outer peripheral surface It is preferable to be configured to change so as to increase the rate.

  According to this configuration, the porosity of the porous portion of the outer structure portion in the main body portion changes so as to increase from the inner portion adjacent to the inner structure portion to the outer peripheral surface side portion. Therefore, in the outer structure portion, the tissue structure of the porous portion changes in an inclined manner so that the porosity is increased. For this reason, it is possible to realize a structure that suppresses abrupt changes in the tissue structure from the inner structure portion configured as a dense body to the outer peripheral surface side of the outer structure portion having the porous portion, and is less likely to cause stress concentration. A structure in which damage is difficult to occur can be realized.

Artificial joints for components according to an aspect of the present invention, the front Kisotogawa structure, has a projecting portion formed integrally on the body portion with projecting outwardly from said body portion, the projecting portion , the distal-side protruding from the body portion is formed in a pointed shape, or it is preferably formed into a shape having a pointed ridge portion.

  According to this configuration, the outer structure portion is provided with a protruding portion having a shape with a sharp tip or a sharp ridgeline portion. For this reason, it fixes so that the sharp part in a protrusion part may bite into a bone. Thereby, the fixation performance with respect to a bone can further be improved. In particular, in the initial state where the artificial joint replacement is performed and the artificial joint component is fixed to the bone, the fixation performance can be further improved. In addition, since the protrusion is formed integrally with the main body portion, there is no joint between the main body portion and the protrusion. For this reason, in the region between the main body part and the protruding part, stress concentration hardly occurs, and a structure that does not easily cause damage even if side pressure acting on the protruding part from the side acts repeatedly is realized. can do.

Artificial joints for components according to an aspect of the present invention, prior Symbol protrusion preferably includes the porous portion.

  According to this configuration, since the protruding portion includes the porous portion, long-term union with the bone is promoted between the protruding portion that has bite into the bone and the bone. For this reason, in addition to the initial fixing performance to the bone, the long-term fixing performance to the bone can be further improved.

Artificial joints for components according to an aspect of the present invention, the front Symbol protrusion configured portion is provided as a dense body distally projecting outwardly of said body portion, radically projecting from the body portion It is preferable that the porous portion is provided on the side.

  According to this configuration, since the dense body is provided on the distal end side of the protruding portion, the rigidity on the distal end side of the protruding portion can be increased. Thereby, the front end side of the projecting portion can easily bite into the bone, and the initial fixing performance with respect to the bone can be further improved. And since a porous part is provided in the root side of a protrusion part, long-term union with a bone is promoted in the root side of a protrusion part. For this reason, in the protrusion part, the initial fixation performance with respect to the bone and the long-term fixation performance can be efficiently balanced.

Artificial joints for components according to an aspect of the present invention, the front Symbol protrusion porosity of the porous portion is changed from the base side projecting from the body portion toward the distal end side projecting toward the outside of the body portion It is preferable that it is comprised.

  According to this configuration, the porosity of the porous portion of the protruding portion changes from the root side to the tip side. For this reason, in the protrusion part, it can suppress that the organization structure of a porous part changes rapidly, and can implement | achieve the structure which is hard to produce stress concentration further. As a result, it is possible to realize a structure in which damage to the protrusion is less likely to occur.

  ADVANTAGE OF THE INVENTION According to this invention, the component for artificial joints which can implement | achieve the structure which does not produce damage easily, can reduce the risk of breakage, and can improve the fixation performance for obtaining the fixation force with respect to a bone can be provided. .

It is sectional drawing which shows the artificial hip joint containing the component for artificial joints concerning one embodiment of this invention. It is sectional drawing which shows typically the cross section of the component for artificial joints shown in FIG. It is a top view of the component for artificial joints shown in FIG. FIG. 3 is an enlarged cross-sectional view schematically showing a part of a cross section of the artificial joint component shown in FIG. 2 in an enlarged manner. It is a schematic diagram which shows typically the manufacturing system for manufacturing the component for artificial joints shown in FIG. It is a figure for demonstrating the process by the manufacturing system shown in FIG. 4, Comprising: It is a schematic diagram which shows the setting value of the irradiation amount of the laser beam of each part in a part of one layer image. It is a flowchart for demonstrating the manufacturing process of the component for artificial joints shown in FIG. It is a schematic diagram which shows typically the manufacturing process of the component for artificial joints shown in FIG. It is sectional drawing which shows typically the cross section of the component for artificial joints which concerns on a modification. It is an expanded sectional view expanding and showing typically a part of section of the component for artificial joints concerning a modification. It is an expanded sectional view expanding and showing typically a part of section of the component for artificial joints concerning a modification. It is an expanded sectional view expanding and showing typically a part of section of the component for artificial joints concerning a modification. It is a figure which shows the artificial shoulder joint containing the component for artificial joints which concerns on a modification.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. The present invention can be widely applied as an artificial joint component to which a ball-shaped component slides or a liner on which the ball-shaped component slides is attached.

[Artificial joint]
FIG. 1 is a cross-sectional view showing an artificial hip joint 10 including an artificial joint component 1 according to an embodiment of the present invention. In FIG. 1, a state where the artificial hip joint 10 is installed in a patient is shown together with a part of the pelvis 101 and a part of the femur 102. As shown in FIG. 1, the artificial hip joint 10 is provided as an artificial joint for allowing relative displacement of the femur 102 with respect to the acetabulum 101 a of the pelvis 101.

  The artificial hip joint 10 includes an artificial joint component 1, a liner 2, a stem 3, and a bone head ball 4. In the present embodiment, an artificial hip joint will be described as an example of an artificial joint.

  The artificial joint component 1 is installed on the acetabulum 101 a of the pelvis 101 and fixed to the pelvis 101. The artificial joint component 1 includes a shell-like main body portion 12 provided with a curved depression surface 11 to which the liner 2 is attached and fixed. In the present embodiment, the main body portion 12 is provided as a hemispherical shell portion.

  Examples of the material for the artificial joint component 1 include metal materials such as titanium, titanium alloy, cobalt chromium alloy, and stainless steel that have been approved as medical devices for living implants. The material for the artificial joint component 1 may be only one type of the above-exemplified metal materials, or may be a plurality of types, or one type having biocompatibility other than those exemplified above or A plurality of types of metal materials may be used.

  The liner 2 is provided as a hemispherical component, and is formed of a polymer material such as polyethylene, for example. The liner 2 is provided with a sliding surface 2a recessed in a hemispherical curved surface on which the head ball 4 slides. As described above, the artificial joint component 1 and the liner 2 are held by the pelvis 101 and form a spherical joint in cooperation with the head ball 4 so as to allow movement of the femur 102 with respect to the pelvis 101. It is configured.

  The stem 3 is provided as a portion that supports the head ball 4 and is fixed to the femur 102 of the patient. The stem 3 is formed in an elongated rod shape or plate shape. A bent portion is provided in the middle portion of the stem 3. The stem 3 includes a stem body 3a and a neck portion 3b. The stem body 3 a is inserted into the medullary cavity 102 a of the femur 102 and is fixed to the femur 102.

  Examples of the material of the stem 3 include metal materials such as titanium, titanium alloy, cobalt chromium alloy, and stainless steel that have been approved as medical devices for living implants. The material of the stem 3 may be only one type of the above-exemplified metal materials, may be a plurality of types, or one or a plurality of types having biocompatibility other than those exemplified above. It may be a metal material.

  The head ball 4 is provided as a ball-shaped component and is formed in a substantially spherical shape. The bone head ball 4 is formed with a fitting hole 4a. The fitting hole 4 a opens at the end opposite to the substantially spherical curved surface portion of the bone head ball 4 and extends toward the inside of the bone head ball 4. By inserting and fitting the distal end side of the neck portion 3b of the stem 3 into the fitting hole 4a, the bone head ball 4 is supported and fixed to the stem 3.

  Examples of the material for the bone head ball 4 include cobalt-chromium alloys, metal materials such as stainless steel, polymer materials such as polyethylene, and ceramic materials such as alumina and zirconia that have been approved as medical equipment for living implants. can do.

  In the present embodiment, the artificial hip joint 10 has been described by taking as an example a configuration in which the head ball 4 is connected to the stem 3, but this need not be the case. For example, the bone head ball 4 may be formed integrally with the stem 3.

[Details of artificial joint components]
Next, the artificial joint component 1 of the present embodiment will be described in more detail. FIG. 2 is a cross-sectional view schematically showing a cross section of the artificial joint component 1. FIG. 3 is a plan view of the artificial joint component 1 and shows the artificial joint component 1 viewed from the direction of arrow A in FIG.

  The artificial joint component 1 shown in FIGS. 1 and 2 includes an inner shell structure portion 13, an outer shell structure portion 14, and a protruding portion 15. The shell-shaped main body portion 12 provided with the recessed surface 11 is constituted by an inner shell structure portion 13 and an outer shell structure portion 14.

  The inner shell structure portion 13 constitutes the inner structure portion in the present embodiment having a portion to which the liner 2 is attached on the recessed surface 11 side of the main body portion 12. In the following description, the inner shell structure portion 13 is also referred to as the inner structure portion 13. The inner shell structure portion 13 is provided as a dense portion 17 that is a structure constituted by a dense body. In the present embodiment, the dense body refers to a portion in which pores are not substantially provided, for example, a portion having a porosity of less than several percent (including zero percent). As described above, the inner shell structure portion 13 is provided as the dense portion 17 formed of a dense body, and a porous body that is a sparser structure than the dense body is not provided.

  The outer shell structure portion 14 and the protruding portion 15 constitute an outer structure portion 16 provided outside the inner structure portion 13. That is, the outer structure portion 16 includes the outer shell structure portion 14 and the protruding portion 15. The outer structure portion 16 includes a porous portion 18 configured as a porous body that is a structure that is sparser than the dense body of the inner structure portion 13.

  The inner structure portion 13 and the outer structure portion 16 are integrally formed. In the present embodiment, the inner structure portion 13 and the outer structure portion 16 are formed in an integrated state by sequentially laminating and once melting metal powder having biocompatibility. That is, the inner structure portion 13 and the outer structure portion 16 are integrally formed by a metal powder additive manufacturing method such as a selective laser melting method.

  As described above, the inner structure portion 13 and the outer structure portion 16 are integrally provided without a joint portion serving as a boundary therebetween. That is, the artificial joint component 1 is configured as a single part, and the entire artificial joint component 1 is integrally formed. As described above, the artificial joint component 1 has a dense body and a porous body, and by varying the amount of melting of the metal powder as the material of the artificial joint component 1, the artificial joint component 1 The component 1 is formed with a dense body and a porous body.

  The porous portion 18 is provided over the entire outer peripheral surface 14 a of the outer shell structure portion 14 that is a portion included in the main body portion 12 in the outer structure portion 16. The porous portion 18 is formed by setting the melting amount of the metal powder, which is the material of the artificial joint component 1, to a predetermined amount or less by the metal powder additive manufacturing method, and has a large number of pores. In this embodiment, the porosity is defined as a value obtained by multiplying the value obtained by dividing the volume B of the pore (space) in the unit volume A by the unit volume A by 100. That is, it can be expressed as porosity = (B / A) × 100.

  FIG. 4 is an enlarged cross-sectional view schematically showing an enlarged part of the cross section of the artificial joint component 1. As schematically shown by hatching in FIG. 4, the outer shell structure portion 14, which is a portion included in the main body portion 12 in the outer structure portion 16, is located on the outer peripheral surface 14 a side from the inner portion adjacent to the inner structure portion 13. The porosity of the porous portion 18 changes so as to increase over this portion. That is, the outer shell structure portion 14 is configured such that the density decreases as it goes toward the outer peripheral surface 14a. In addition, the porosity in the outer shell structure portion 14 may be set to increase continuously toward the outer peripheral surface 14a, or may be set to increase stepwise.

  The protruding portion 15 protrudes outward from the outer shell structure portion 14 of the main body portion 12 and is integrally formed with the main body portion 12. In the present embodiment, a plurality of projecting portions 15 are provided and are arranged along the edge portion of the outer shell structure portion 14. In addition, in this embodiment, the form with which the four protrusion parts 15 were provided is illustrated, and the four protrusion parts 15 are provided at equal intervals along the circumferential direction of the edge part of the outer shell structure part 14. FIG. . That is, the four protrusions 15 are arranged along the circumference of the edge portion of the outer shell structure portion 14 at equal angular intervals (that is, 90 ° intervals) at an angle in the circumferential direction centering on the center position. ing.

  In addition, each protrusion 15 is formed in a shape with a sharp tip that protrudes from the outer shell structure 14. In the present embodiment, each projecting portion 15 is formed in a triangular prism shape having a pointed tip side and a shape having a ridge portion sharpened in a fin shape. When the artificial joint component 1 is installed so as to be fitted into the acetabulum 101 a, the fin-shaped sharp ridge line bites into the pelvis 101. In addition, the surface of each protrusion part 15 is formed as a flat surface in which the groove | channel-shaped or recessed part is not provided over the whole except a ridgeline part.

  Each protrusion 15 includes a porous portion 18. The porous portion 18 in the protruding portion 15 is provided outside the protruding portion 15 (on the side opposite to the inner shell structure portion 13 side), and is provided continuously with the porous portion 18 in the outer shell structure portion 14. In addition, as schematically shown by hatching in FIG. 4, each projecting portion 15 has a porosity of the porous portion 18 from the base side projecting from the main body portion 12 to the tip side projecting outward from the main body portion 12. Is configured to change so as to increase. That is, each protrusion 15 is configured such that the density decreases as the distance from the main body portion 12 increases. Each protruding portion 15 is provided with a dense portion 17 that is continuous with the dense portion 17 of the inner shell structure portion 13 on the base side protruding from the main body portion 12.

  Further, as described above, the artificial joint component 1 is formed by the metal powder additive manufacturing method, but the hollow surface 11 which is the inner peripheral surface of the inner shell structure portion 13 is subjected to a surface finishing process. Yes. That is, the recessed surface 11 where the dense portion 17 is exposed is subjected to a surface finishing process as machining. Examples of the machining include at least one of a turning process, a grinding process, and a polishing process. For example, the mirror surface processing may be performed on the hollow surface 11 as the surface of the dense portion 17 by performing such machining.

[Manufacturing system for artificial joint components]
FIG. 5 is a schematic view of a manufacturing system 20 for manufacturing the artificial joint component 1. As shown in FIG. 5, the manufacturing system 20 includes a CAD (Computer Aided Design) device 21, a data conversion device 22, and a manufacturing device 23.

  The CAD device 21 is, for example, a 3D-CAD device that can display an image three-dimensionally on a screen. In the present embodiment, the CAD device 21 includes a computer and software installed in the computer. The designer of the artificial joint component 1 creates CAD data (image data) for creating the artificial joint component 1 by operating the CAD device 21. The CAD data created by the CAD device 21 is output to the data conversion device 22.

  The data conversion device 22 is provided as a device that converts CAD data into data for operating the manufacturing device 23. In the present embodiment, the data conversion device 22 includes a computer and software installed on the computer. The data conversion device 22 is, for example, a plurality of layer images (two-dimensional images) obtained by slicing a three-dimensional image of the artificial joint component 1 specified by CAD data at predetermined intervals along a predetermined direction. And the data of the plurality of layer images is held. For example, as shown by a double-ended arrow B in FIG. 2, the predetermined direction is set as a direction perpendicular to the end surface 12 a on the inner shell structure portion 13 side in the hemispherical shell-shaped main body portion 12. Further, the predetermined interval corresponds to the thickness of one layer of metal powder to be laminated in the manufacturing apparatus 23, and is, for example, about 30 μm. The data of the plurality of layer images is given to the manufacturing apparatus 23.

  The manufacturing apparatus 23 is an apparatus for melting and once solidifying the metal powder and solidifying the powder as a solid. In the present embodiment, the manufacturing apparatus 23 forms the artificial joint component 1 by a metal powder additive manufacturing method as a selective laser melting method. In the present embodiment, the manufacturing apparatus 23 includes a laser light source 24, a control unit 25, a movable base 26, and a powder supply unit 27.

  The laser light source 24 is provided to give thermal energy to the metal powder. In the present embodiment, the laser light source 24 is a Yb (ytterbium) fiber laser light source. The laser beam from the laser light source 24 may be irradiated to a desired position of the metal powder by the laser light source 24 itself being displaced using a driving device (not shown), or the laser light source 24 is fixed. Then, a desired position may be irradiated using a galvanometer mirror. The laser light source 24 is controlled by the control unit 25.

  The control unit 25 includes a CPU, a RAM, a ROM, and the like, and receives data from the data conversion device 22. The control unit 25 controls the laser light source 24, the movable table 26 and the powder supply unit 27. More specifically, the control unit 25 determines the irradiation amount of the laser beam to a predetermined portion of the metal powder based on the image data given from the data converter 22, and based on the determined irradiation amount, the metal powder A laser beam is irradiated to a predetermined portion of Note that the irradiation amount of the laser beam may be set by the data converter 22.

  FIG. 6 is a diagram for explaining processing by the control unit 25 for setting the irradiation amount of the laser beam to the predetermined portion of the metal powder, and the setting value of the irradiation amount of the laser beam at each part in a part of one layer image. It is a schematic diagram which shows. FIG. 6 shows a part of a layer image showing a cross section of the main body portion 12 of the artificial joint component 1. More specifically, FIG. 6 shows one in the circumferential direction of the ring-shaped cross section of the main body portion 12 parallel to the end face 12a among the layer images of the cross section taken along the line CC in FIG. Shows the part.

  As shown in FIG. 6, the layer image is composed of a plurality of pixels. Each pixel is set to a size corresponding to the minimum unit area that can be irradiated with a laser beam at one time, for example. In FIG. 6, the relationship between the size of the pixel and the size of the artificial joint component 1 is schematically shown. As described above, the artificial joint component 1 is formed by varying the melting amount of the metal powder depending on the location. For this reason, in the layer image data, the laser beam irradiation amount is set for each pixel.

  In the present embodiment, the dense part 17 provided over the inner shell structure part 13 and the part on the base side of each protruding part 15 is formed of a dense body, and substantially no pores are formed. Therefore, in order to form the dense portion 17, it is necessary to melt the metal powder sufficiently to the extent that no pores are formed. For this reason, in the layer image shown in FIG. 6, the irradiation amount (irradiation energy per unit time) of the region 31 corresponding to the dense portion 17 is set to the largest value in the layer image. In the layer image shown in FIG. 6, hatched hatching is given to pixels irradiated with the laser beam, and the setting value of the laser beam irradiation amount is larger as the hatched hatching interval is shorter. Yes.

  The porous portion 18 is set so that the porosity increases from the portion adjacent to the dense portion 17 to the outside of the main body portion 12. For this reason, in FIG. 6, the form by which the porous part 18 is comprised by the part of three area | regions (32, 33, 34) from which a porosity differs is illustrated. A portion of the region 32 in the porous portion 18 adjacent to the portion of the region 31 that is the dense portion 17 is configured as a portion having the smallest porosity in the porous portion 18. For this reason, the melting amount of the metal powder when forming the portion of the region 32 is set larger next to the melting amount of the metal powder when forming the portion of the region 31. Therefore, in the layer image shown in FIG. 6, the setting value of the laser beam irradiation amount to the region 32 is set to be the second largest after the region 31.

  A portion of the region 33 adjacent to the portion of the region 32 in the porous portion 18 is configured as a portion having a larger porosity than the portion of the region 32 in the porous portion 18. For this reason, the melting amount of the metal powder when forming the portion of the region 33 is set smaller than the melting amount of the metal powder when forming the portion of the region 32. Therefore, in the layer image shown in FIG. 6, the setting value of the laser beam irradiation amount to the region 33 is set smaller than that of the region 32.

  Further, the portion of the region 34 adjacent to the portion of the region 33 in the porous portion 18 is the outermost portion of the main body portion 12 and is configured as the portion having the highest porosity in the porous portion 18. For this reason, the melting amount of the metal powder when forming the region 34 is set to be the smallest in the porous portion 18. Therefore, in the layer image shown in FIG. 6, the setting value of the irradiation amount of the laser beam to the region 34 is set to the smallest.

  In the layer image shown in FIG. 6, pixels that are not hatched indicate regions that are not irradiated with a laser beam. Although one layer has been described with reference to FIG. 6, in each layer image, the amount of laser beam irradiation is appropriately set for each pixel, as described above.

  In the above description, the porous portion 18 is configured by three regions (32, 33, 34) having different porosities. However, this need not be the case. A form in which the porous portion 18 is configured by two or less region portions or four or more region portions having different porosities may be implemented. Moreover, in the porous part 18, the form in which the magnitude | size and arrangement | positioning of the part of the area | region where porosity differ from each other may be implemented variously.

  The metal powder irradiated with the laser beam is placed on the movable table 26 (see FIG. 5). The movable table 26 is provided to hold the metal powder. The movable base 26 has, for example, a substantially horizontal upper surface, and metal powder is placed on the upper surface. The movable base 26 has a drive mechanism (not shown) and can be displaced along the vertical direction perpendicular to the upper surface. Metal powder is supplied from the powder supply unit 27 to the movable table 26.

  The powder supply unit 27 includes a storage unit that stores the metal powder and a supply unit that supplies the metal powder onto the movable base 26. The powder supply unit 27 forms a metal powder layer having a thickness (in this embodiment, 30 μm) corresponding to the above-described predetermined interval on the movable table 26.

[Manufacturing process for artificial joint components]
Next, the process of manufacturing the artificial joint component 1 will be described with reference to FIG. FIG. 7 is a flowchart for explaining a manufacturing process of the artificial joint component 1. When manufacturing the artificial joint component 1, first, the designer creates CAD data of the artificial joint component 1 by using the CAD device 21 (step S1).

  The CAD data of the artificial joint component 1 is output to the data conversion device 22 in response to, for example, the designer operating the CAD device 21 (step S2). The data conversion device 22 divides the image of the artificial joint component 1 specified by the CAD data into a plurality of layers for each predetermined thickness, and outputs the image data of each layer to the control unit 25 of the manufacturing device 23. (Step S3). The control unit 25 reads the image data of each layer and sets the laser beam irradiation amount to each pixel of each layer (step S4).

  Next, the control unit 25 drives the powder supply unit 27. Thereby, as shown in FIG. 8A, the powder supply unit 27 forms the metal powder layer 41 having the predetermined thickness (30 μm in the present embodiment) described above on the upper surface of the movable base 26 (step S5). . That is, a metal powder is prepared. Next, the control unit 25 drives the laser light source 24. Accordingly, the laser light source 24 irradiates a predetermined portion of the metal powder layer 41 with a predetermined amount of laser light according to the irradiation amount of the laser light set by the control unit 25 (step S6). As a result, as shown in FIG. 8B, a part of the metal powder layer 41 is once melted, and the melted part is solidified and integrated.

  Next, the control unit 25 determines whether or not the work of once melting and integrating the metal powder is performed for all layers as described above (step S7). When this operation is not completed (No in step S7), the control unit 25 drives the movable table 26 and displaces the movable table 26 downward by the same value as the thickness of the metal powder layer 41 (step S8). .

  The control unit 25 drives the powder supply unit 27 again. Thereby, the powder supply part 27 forms a metal powder layer again (step S5). Next, the control unit 25 drives the laser light source 24. Thereby, the laser light source 24 irradiates a predetermined amount of the laser beam to a predetermined portion of the metal powder layer according to the irradiation amount of the laser beam set by the control unit 25 (step S6). Thereby, a part of the metal powder layer is once melted, and the melted part is solidified and integrated. In this way, the artificial joint component 1 is formed by varying the melting amount of the metal powder depending on the location.

  In the manufacturing apparatus 23, step S5 to step S8 are repeated until the operation of once melting and integrating the metal powder is performed for all layers. As a result, as shown in FIG. 8C, the metal powder layers n, n + 1, n + 2,... (N is a positive integer) are laminated, and the artificial joint component 1 is formed. In the artificial joint component 1, the dense portion 17 corresponding to the region 31 in the layer image of FIG. 6 is formed. Moreover, the porous part 18 corresponding to the area | region (32, 33, 34) in the layer image of FIG. 6 among the components 1 for artificial joints is formed. In addition, in FIG.8 (c), the code | symbol of area | region (31-34) is also shown typically.

  When it is determined by the control unit 25 that the work of once melting and integrating the metal powder has been performed for all layers (Yes in step S7), the work is completed and post-processing is performed (step S9). In the present embodiment, the post-processing is performed by removing the artificial joint component 1 formed on the movable table 26 from the movable table 26 and removing unnecessary metal powder adhering to the artificial joint component 1 from the artificial joint component 1. Includes removal process. This removal process includes, for example, a process of ultrasonically cleaning the artificial joint component 1 using 2-propanol, pure water, or the like. Moreover, in this embodiment, a post-processing process includes the machining process performed after said removal process. In this machining process, a portion of the dense portion 17 of the artificial joint component 1 exposed to the outside is ground or polished. That is, the end surface 12a of the main body portion 12 and the recessed surface 11 are ground or polished. The artificial joint component 1 is completed through these post-processing steps.

[effect]
As described above, in the artificial joint component 1, the inner structure portion 13 configured as a dense body and the outer structure portion 16 having the porous portion 18 are integrally formed. For this reason, there is no junction between the inner structure portion 13 and the outer structure portion 16, and stress concentration hardly occurs, and a structure that does not easily cause damage even when repeated stress is applied is realized. be able to. Thereby, the risk of breakage can be reduced. And according to the component 1 for artificial joints, since the outer structure part 16 is provided with the porous part 18, a large frictional force can be secured between the bones, and the fixing performance for obtaining the fixing force with respect to the bone can be improved. Secure fixing performance. Furthermore, since the porous portion 18 is provided in the outer structure portion 16, the bone grows so that bone enters the pores of the porous portion 18 in the long term. Thereby, it is easy to promote the fusion with the bone, and the long-term fixing performance to the bone can be improved.

  Therefore, according to the present embodiment, there is provided the artificial joint component 1 that can realize a structure in which damage is unlikely to occur, reduce the risk of breakage, and can improve the fixing performance for obtaining the fixing force to the bone. can do.

  Moreover, according to the component 1 for artificial joints, the inner structure part 13 and the outer structure part 16 are formed in an integrated state by sequentially laminating and once melting metal powders. That is, the inner structure portion 13 and the outer structure portion 16 are integrally formed by a metal powder additive manufacturing method. For this reason, it is not necessary to perform a complicated cutting process etc. with respect to a metal and to form the component for artificial joints which has a porous part. Further, even a difficult-to-cut material such as a titanium alloy that is widely distributed as a material for medical instruments does not require a complicated shape, so the artificial joint component 1 can be easily formed. . Therefore, the artificial joint component 1 including the inner structure portion 13 configured as a dense body and the outer structure portion 16 having the porous portion 18 can be easily formed integrally.

  Further, according to the artificial joint component 1, since the porous portion 18 is provided on the entire outer peripheral surface 14a of the outer structure portion 16 in the main body portion 12, a larger frictional force can be secured between the bone and the bone can be fixed. Further improvement can be achieved. Moreover, since the area | region where long-term union with a bone is accelerated | stimulated increases, the long-term fixation performance with respect to a bone can further be improved.

  Further, according to the artificial joint component 1, the porosity of the porous portion 18 of the outer structure portion 16 in the main body portion 12 changes so as to increase from the inner portion adjacent to the inner structure portion 13 to the outer peripheral surface 14a side portion. To do. Therefore, in the outer structure portion 16, the tissue structure of the porous portion 18 changes in an inclined manner so that the porosity is increased. For this reason, a structure in which the tissue structure is suppressed from abruptly changing from the inner structure portion 13 configured as a dense body to the outer peripheral surface 14a side of the outer structure portion 16 having the porous portion 18 and stress concentration is less likely to occur. A structure that can be realized and is less susceptible to damage can be realized.

  Further, according to the artificial joint component 1, the outer structure portion 16 is provided with the protruding portion 15 having a shape in which the tip side is sharp and the ridge line portion is sharp. For this reason, the sharp part in the protrusion part 15 will be fixed so that it may bite into a bone. Thereby, the fixation performance with respect to a bone can further be improved. In particular, in the initial state in which the artificial joint replacement is performed and the artificial joint component 1 is fixed to the bone, the fixing performance can be further improved. Further, since the protruding portion 15 is formed integrally with the main body portion 12, there is no joint portion serving as a boundary between the main body portion 12 and the protruding portion 15. For this reason, stress concentration is unlikely to occur in the region between the main body portion 12 and the protruding portion 15, and damage is unlikely to occur even if a lateral pressure acting on the protruding portion 15 from the side acts repeatedly. A structure can be realized.

  In addition, according to the artificial joint component 1, since the porous portion 18 is included in the protruding portion 15, long-term fusion with the bone is promoted between the protruding portion 15 biting into the bone and the bone. For this reason, in addition to the initial fixing performance to the bone, the long-term fixing performance to the bone can be further improved.

  Moreover, according to the component 1 for artificial joints, the porosity of the porous portion 18 of the protruding portion 15 changes from the root side to the tip side. For this reason, in the protrusion part 15, it can suppress that the structure | tissue structure of the porous part 18 changes rapidly, and can implement | achieve the structure which is hard to produce stress concentration further. As a result, it is possible to realize a structure in which damage to the protrusion 15 is less likely to occur.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications are possible as long as they are described in the claims. For example, the following modifications may be made.

[Modification]
(1) In the above-described embodiment, the example in which the liner on which the ball-shaped component slides is attached to the recessed surface provided in the main body portion of the artificial joint component has been described. Also good. A configuration in which the liner is not attached to the hollow surface of the body portion of the prosthetic joint component and the ball-like component slides directly may be implemented.

(2) In the above-described embodiment, an example in which the artificial joint component is integrally formed by the metal powder additive manufacturing method has been described as an example, but this need not be the case. For example, the artificial joint component may be integrally formed by sintering a metal powder having biocompatibility.

(2) In the above-described embodiment, the outer shell structure portion provided as a shell-like portion outside the inner structure portion in the main body portion and the protruding portion protruding from the outer shell structure portion are provided outside the inner structure portion. In the above description, the configuration of the outer structure portion is described as an example, but this need not be the case. An embodiment in which the entire main body portion constitutes the inner structure portion and the protruding portion protruding from the main body portion constitutes the outer structure portion may be implemented. In this case, the main body portion that is the inner structure portion is configured as a dense body, and the projecting portion that is the outer structure portion includes the porous portion.

(3) In the above-described embodiment, the protruding portion formed in a shape having a fin-shaped ridge line portion has been described as an example, but the shape of the protruding portion may not be this. Various changes may be made to the shape, number, and arrangement of the protrusions. FIG. 9 is a cross-sectional view schematically showing a cross section of the artificial joint component 51 according to the modification. Similar to the artificial joint component 1, the artificial joint component 51 is used in an artificial hip joint. The artificial joint component 51 includes an inner shell structure portion 13, an outer shell structure portion 14, and a protruding portion 52, and is integrally formed by a metal powder additive manufacturing method. However, the artificial joint component 51 is different from the artificial joint component 1 in the configuration of the protruding portion 52. Hereinafter, the difference between the artificial joint component 51 and the above-described embodiment will be mainly described, and the description of the same configuration as the above-described embodiment will be given by attaching the same reference numerals in the drawings or refer to the same reference numerals. Will be omitted.

  As shown in FIG. 9, the protruding portion 52 protrudes outward from the outer shell structure portion 14 of the main body portion 12 and is integrally formed with the main body portion 12. In the artificial joint component 51, the outer shell structure portion 14 and the protruding portion 52 constitute an outer structure portion 53 provided outside the inner structure portion 13. And the outer side structure part 53 has the porous part 18 comprised as a porous body which is a sparse structure rather than the dense body (dense part 17) of the inner side structure part 13. As shown in FIG.

  In the artificial joint component 51, a plurality of protrusions 52 are provided and arranged along the outer peripheral surface 14 a of the outer shell structure portion 14. In addition, the arrangement | positioning form of the protrusion part 52 which protrudes toward the outer side from the outer peripheral surface 14a can be implemented by changing variously. In addition, each protrusion 52 is formed in a substantially conical shape with a sharp tip protruding from the outer shell structure portion 14. And each protrusion part 52 is provided so that the front end side may extend along the direction perpendicular | vertical with respect to the end surface 12a by the side of the inner shell structure part 13 in the hemispherical shell-shaped main-body part 12. FIG. When the artificial joint component 51 is installed so as to be fitted into the acetabulum 101a, the above-mentioned conical pointed end side bites into the pelvis 101. In addition, the surface of each protrusion part 52 is formed as a smooth curved surface not provided with a groove-shaped or recessed-shaped portion over the entire portion excluding the pointed portion. In addition, each protrusion part 52 does not need to be along the direction perpendicular | vertical to the end surface 12a by the side of the inner shell structure part 13 at the front end side.

  Each protrusion 52 is configured to include the porous portion 18. The porous portion 18 in the protruding portion 52 is provided over the entire protruding portion 52, and is provided continuously with the porous portion 18 in the outer shell structure portion 14. In addition, each protrusion part 52 may be comprised so that the porosity of the porous part 18 may change from the base side which protrudes from the main-body part 12 to the front end side which protrudes toward the outer side of the main-body part 12, for example. In this case, the porosity of the porous portion 18 in each projecting portion 52 may change so as to increase or decrease so as to decrease from the root side to the tip side. Moreover, the porosity of the porous part 18 in each protrusion part 52 may be constant.

  According to the artificial joint component 51, the outer structure portion 53 is provided with the protruding portion 52 having a pointed tip side. For this reason, the sharp part in the protrusion part 52 will be fixed so that it may bite into a bone. Thereby, the fixation performance with respect to a bone can further be improved. In particular, in the initial state where the artificial joint replacement is performed and the artificial joint component 51 is fixed to the bone, the fixing performance can be further improved. Further, since the protruding portion 52 is formed integrally with the main body portion 12, there is no joining portion serving as a boundary between the main body portion 12 and the protruding portion 52. For this reason, stress concentration is unlikely to occur in the region between the main body portion 12 and the protruding portion 52, and damage is unlikely to occur even when side pressure acting on the protruding portion 52 from the side acts repeatedly. A structure can be realized.

(4) FIGS. 10 to 12 are diagrams showing further modifications of the protruding portion 52 of the artificial joint component 51 according to the modification of FIG. 10 to 12 are enlarged cross-sectional views schematically showing an enlarged part of the cross section of the protruding portion in the artificial joint component according to the modification. Each of the projecting portions (54, 55, 56) according to the modification shown in FIGS. 10 to 12 is formed in a substantially conical shape with a pointed distal end projecting from the outer shell structure portion 14. In the following description, the protrusions (54, 55, 56) will mainly be described in terms of differences from the above-described embodiment or the modification shown in FIG. 9, and the above-described embodiment or the modification shown in FIG. The description of the same configuration as in FIG. 5 will be omitted by giving the same reference numerals in the drawings or by quoting the same reference numerals.

  The protruding portion 54 shown in FIG. 10 is provided with a dense portion 17 that is a portion configured as a dense body on the distal end side that protrudes toward the outside of the main body portion 12, and as a porous body on the base side that protrudes from the main body portion 12. The porous portion 18 is provided. It should be noted that the protruding portion 54 is provided so that the dense portion 17 on the tip side provided so as to be exposed to the outside extends continuously to the dense portion 17 in the inner shell structure portion 13 of the main body portion 12. Moreover, in the protrusion part 54, the porous part 18 provided in the root side is provided so that it may be exposed outside.

  According to the configuration according to the above modification, since the dense body (the dense portion 17) is provided on the distal end side of the protruding portion 54, the rigidity on the distal end side of the protruding portion 54 can be increased. Thereby, the front end side of the protrusion part 54 becomes easy to bite into a bone, and the further improvement of the initial fixation performance with respect to a bone can be aimed at. And since the porous 18 part is provided in the root side of the protrusion part 54, long-term union with the bone is promoted on the root side of the protrusion part 54. For this reason, in the protrusion part 54, the initial fixation performance with respect to a bone | frame and long-term fixation performance can be made to make compatible efficiently.

  The protruding portion 55 shown in FIG. 11 is provided with a porous portion 18 as a porous body over the entire surface layer portion exposed to the outside. And the inside in the protrusion part 55 is comprised by the dense part 17 as a dense body. The porous portion 18 in the protruding portion 55 is provided so as to be continuous with the porous portion 18 on the outer peripheral surface 14 a of the outer shell structure portion 14. Further, the dense portion 17 in the protruding portion 55 is provided so as to continue to the dense portion 17 in the inner shell structure portion 13. According to this configuration, since the porous 18 portion is provided over the entire surface of the protruding portion 55, long-term fusion with the bone can be further promoted. In addition, since most of the inside of the protruding portion 55 is constituted by the dense portion 17, the rigidity of the protruding portion 55 is increased as a whole, a structure that is more easily bite into the bone is realized, and the initial fixing performance is further improved. It can also be improved.

  In the protruding portion 56 shown in FIG. 12, a plurality of porous portions 18 as porous bodies provided partially are arranged in a discrete state on the surface layer portion exposed to the outside. That is, a plurality of porous portions 18 are provided on the surface of the protruding portion 56 in a dispersed manner. And the protrusion part 56 is comprised by the dense part 17 as a dense body in parts other than the several porous part 18 distributed and provided in the surface. Further, the dense portion 17 in the protruding portion 56 is provided so as to continue to the dense portion 17 in the inner shell structure portion 13. According to this configuration, since the porous portion 18 is provided dispersed on the surface of the protruding portion 56, long-term fusion with bone can be promoted. In addition, since most of the protruding portion 56 is constituted by the dense portion 17, the rigidity of the protruding portion 56 is increased, and a structure that is more easily bite into the bone can be realized to further improve the initial fixing performance. it can.

(5) In the above-described embodiment, the artificial joint component applied to the artificial hip joint has been described as an example. However, this need not be the case. The present invention can be widely applied to an artificial joint component to which a ball-shaped component slides or a liner on which a ball-shaped component slides is attached. For example, an artificial joint component applied to an artificial shoulder joint may be implemented.

  FIG. 13 is a diagram showing an artificial shoulder joint 60 including an artificial joint component 61 according to a modification. The artificial shoulder joint 60 includes an artificial joint component 61, a stem 62, and a bone head 63. In FIG. 13, the outer shape of the stem 62 and the bone head 63 is shown, and the cross section of the artificial joint component 61 is shown. The artificial joint component 61 is fixed to a patient's scapula (not shown). The component for artificial joint 61 includes a shell-like main body portion 65 provided with a curved concave surface 64 on which the bone head 63 slides.

  Examples of the material of the artificial joint component 61 include metal materials such as titanium, titanium alloy, cobalt chrome alloy, and stainless steel that have been approved as medical devices for living implants. The material of the artificial joint component 61 may be only one type of the metal materials exemplified above, or may be a plurality of types, or one type having biocompatibility other than those exemplified above or A plurality of types of metal materials may be used.

  The stem 62 is provided as a portion that supports the bone head 63 and is fixed to the humerus of a patient (not shown). The stem 62 is formed in an elongated rod shape or plate shape. Examples of the material of the stem 62 include metal materials such as titanium, titanium alloy, cobalt chrome alloy, and stainless steel that have been approved as medical devices for living implants.

  The head 63 is provided as a ball-shaped component formed in a semi-elliptical sphere, and is formed in a shape that constitutes a part of the semi-elliptical sphere. The bone head 63 is fixed to the stem 62 by fitting, for example. The bone head 63 may be formed integrally with the stem 62. Examples of the material of the bone head 63 include cobalt chromium alloy, metal material such as stainless steel, polymer material such as polyethylene, and ceramic material such as alumina and zirconia that have been approved as medical equipment for living implants. be able to.

  Here, the artificial joint component 61 will be described in more detail. The artificial joint component 61 includes an inner shell structure portion 66, an outer shell structure portion 67, and a protruding portion 68. The shell-like main body portion 65 provided with the recessed surface 64 is constituted by an inner shell structure portion 66 and an outer shell structure portion 67.

  The inner shell structure portion 66 constitutes an inner structure portion in the present embodiment having a portion on the recessed surface 64 side of the main body portion 65 and a portion on which the bone head 63 slides. In the following description, the inner shell structure portion 66 is also referred to as an inner structure portion 66. The inner shell structure portion 66 is provided as a dense portion 70 that is a structure constituted by a dense body. The inner shell structure portion 66 is not provided with a porous body that is a sparser structure than the dense body.

  The outer shell structure portion 67 and the protruding portion 68 constitute an outer structure portion 69 provided outside the inner structure portion 66. That is, the outer structure portion 69 includes an outer shell structure portion 67 and a protruding portion 68. The outer structure portion 69 includes a porous portion 71 configured as a porous body that is a sparser structure than the dense structure of the inner structure portion 64.

  The inner structure portion 66 and the outer structure portion 69 are integrally formed. In the artificial joint component 61, the inner structure portion 66 and the outer structure portion 69 are formed in an integrated state by sequentially laminating and once melting metal powder having biocompatibility. That is, the inner structure portion 66 and the outer structure portion 69 are integrally formed by a metal powder additive manufacturing method such as a selective laser melting method. In addition, the manufacturing system and manufacturing process of the artificial joint component 61 by the metal powder additive manufacturing method are configured in the same manner as in the above-described embodiment.

  As described above, the inner structure portion 66 and the outer structure portion 69 are provided integrally without a joint portion serving as a boundary between them. That is, the artificial joint component 61 is configured as a single part, and the entire artificial joint component 61 is integrally formed. As described above, the artificial joint component 61 has a dense body and a porous body, and by varying the amount of melting of the metal powder as the material of the artificial joint component 61, the artificial joint component 61 The component 61 is formed with a dense body and a porous body.

  The porous portion 71 is provided over the entire outer peripheral surface 67 a of the outer shell structure portion 67 which is a portion included in the main body portion 65 in the outer structure portion 69. The porous portion 71 is formed by setting the melting amount of the metal powder, which is the material of the artificial joint component 61, to a predetermined amount or less by the metal powder additive manufacturing method, similarly to the porous portion 18 in the above-described embodiment, It has many pores. The porosity of the porous portion 71 of the outer shell structure portion 67 which is a portion included in the main body portion 65 in the outer structure portion 69 changes from the inner portion adjacent to the inner structure portion 66 to the portion on the outer peripheral surface 67a side. It may be configured as follows. Further, the outer shell structure portion 67 may be configured so that the porosity of the porous portion 71 is constant.

  The protruding portion 68 protrudes outward from the outer shell structure portion 67 of the main body portion 65 and is integrally formed with the main body portion 65. In the present embodiment, a plurality of protrusions 68 are provided and are arranged along the outer peripheral surface 67 a of the outer shell structure portion 67. In addition, the arrangement | positioning form of the protrusion part 68 which protrudes toward the outer side from the outer peripheral surface 67a can be implemented in various changes.

  Moreover, each protrusion 68 is formed in a substantially conical shape with a sharpened tip side protruding from the outer shell structure 67, for example. Each protrusion 68 is provided so as to extend along a direction parallel to the fitting direction when the artificial joint component 61 is fitted into the scapula. Thereby, when the artificial joint component 61 is fitted and installed in the scapula, the above-mentioned conical pointed end side bites into the scapula. It should be noted that the surface of each protrusion 68 is formed as a smooth curved surface not provided with a groove-shaped or recessed-shaped portion over the entire portion excluding the pointed portion.

  Each protrusion 68 includes a porous portion 71. The porous portion 71 in the protruding portion 68 is provided over the entire protruding portion 68, and is provided continuously with the porous portion 71 in the outer shell structure portion 67. In addition, each protrusion part 68 may be comprised so that the porosity of the porous part 71 may change from the base side which protrudes from the main-body part 65 to the front end side which protrudes toward the outer side of the main-body part 65, for example. In this case, the porosity of the porous portion 71 in each projecting portion 68 may change so as to increase from the root side to the tip side, or may change so as to decrease. Moreover, the porosity of the porous part 71 in each protrusion part 68 may be constant.

  According to the above modification, the same effects as those of the above-described embodiment can be obtained. That is, according to the above-described modification, the artificial joint component 61 that realizes a structure in which damage is difficult to occur, reduces the risk of breakage, and can improve the fixing performance for obtaining a fixing force to the bone. Can be provided.

  The present invention can be widely applied as an artificial joint component to which a ball-shaped component slides or a liner on which a ball-shaped component slides is attached.

1 Artificial joint component 2 Liner 4 Bone head ball (ball-shaped component)
11 hollow surface 12 body portion 13 inner shell structure (inner structure)
16 Outer structure part 17 Dense part 18 Porous part

Claims (4)

A component for an artificial joint having a shell-like main body portion provided with a curved concave surface to which a ball-shaped component slides or a liner on which the ball-shaped component slides is attached,
An inner structure part having at least a part to which the ball-shaped component slides or to which the liner is attached, and an outer structure provided on the outer side of the inner structure part. And comprising
The inner structure portion is configured as a dense body, and the outer structure portion has a porous portion configured as a porous body that is a sparse structure than the dense body of the inner structure portion,
The inner structure part and the outer structure part are made of an integrally molded metal material,
The outer structure portion has a protruding portion that protrudes outward from the main body portion and is integrally formed with the main body portion,
The projecting portion is formed in a shape with a pointed tip side protruding from the main body portion, or a shape having a pointed ridge line portion,
The protruding portion is provided with a portion configured as a dense body on the tip side protruding toward the outside of the main body portion, and the porous portion is provided on the base side protruding from the main body portion,
The prosthetic joint component, wherein the dense body on the tip side of the projecting portion and the porous portion on the base side of the projecting portion are made of an integrally formed metal material. The component for an artificial joint according to claim 1 ,
The artificial joint component, wherein the porous portion is provided over the entire outer peripheral surface of a portion included in the main body portion of the outer structure portion. The artificial joint component according to claim 1 or 2 ,
The portion included in the main body portion in the outer structure portion is configured to change so that the porosity of the porous portion increases from an inner portion adjacent to the inner structure portion to a portion on the outer peripheral surface side. A component for artificial joints. The artificial joint component according to any one of claims 1 to 3 ,
The prosthetic joint is characterized in that the porosity of the porous portion changes from a base side protruding from the main body portion to a distal end side protruding toward the outside of the main body portion. Components.

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