CN108095863A - A kind of 3D printing cervical artificial disc prosthese - Google Patents

Abstract

The invention discloses a 3D printed artificial cervical intervertebral disc prosthesis, which comprises a prosthetic upper endplate, a prosthetic lower endplate, and a prosthetic nucleus pulposus arranged between the prosthetic upper endplate and the prosthetic lower endplate. The upper surface of the upper end plate of the prosthesis is provided with a first microporous surface, and the first inverted teeth are distributed on the first microporous surface; the lower surface of the lower end plate of the prosthesis is provided with There is a second microhole surface, and second inverted teeth are distributed on the second microhole surface; the prosthetic nucleus pulposus includes an oval base. The device has the following advantages: the device is designed through the reverse reverse technology, and it is a complete bionic design. There is no need to polish the upper and lower endplates, and the integrity of the vertebral endplates is relatively preserved; this device can be quickly manufactured by 3D printing technology, and in actual application, it can also simplify the implantation process, shorten the operation time, and improve the safety of the operation.

Description

A 3D printed artificial cervical disc prosthesis

technical field

The invention relates to an orthopedic implant device, in particular to a 3D printed artificial cervical intervertebral disc prosthesis.

Background technique

Cervical spondylosis is a degenerative disease in which the degenerative changes of the cervical intervertebral disc and its secondary pathological changes involve the surrounding tissue structure and produce clinical symptoms. Epidemiological statistics show that the incidence of cervical spondylosis in my country is about 17.3%, and the incidence is increasing year by year, and the age of onset tends to be younger recently. Anterior cervical decompression and bone graft fusion is currently a classic operation for cervical spondylosis, but a large number of studies have found that it has many complications, such as adjacent segment degeneration and pseudarthrosis formation. At this time, intervertebral disc replacement is attracting more and more attention, and the short-term efficacy of CDR has been recognized by everyone, but it has certain application limitations due to the current design of the prosthesis. Recently, complications related to CDR prosthesis are common. Therefore, More reasonable prosthesis design is particularly important.

The artificial cervical intervertebral disc is an artificial prosthesis with movable joints made of biomaterials such as medical alloys and polymers. After implantation, it replaces the function of the degenerated intervertebral disc and reconstructs the biomechanical characteristics of the spine to the greatest extent. At present, the commonly used cervical disc prosthesis can be divided into two types according to different material designs: metal-to-metal prosthesis and metal-to-polymer prosthesis. The former includes Prestige prosthesis and CerviCore prosthesis, and the latter includes Bryan prosthesis, Prodisc-C prosthesis, PCM disc prosthesis, Mobi-C prosthesis, and Discover prosthesis. However, none of the existing prostheses is a completely bionic structure, and the vertebral endplate needs to be polished during implantation, which will inevitably destroy the integrity of the vertebral body endplate, which will be related to prosthetic complications such as subsidence.

Although cervical disc replacement is being more and more widely used clinically, we should also be soberly aware that the clinical application of cervical disc replacement still has certain limitations. First of all, in terms of material science, the population of cervical spondylosis is getting younger and younger, which requires prosthetic materials to have better anti-corrosion and anti-wear properties; secondly, compared with ACDF, the price of cervical disc replacement It is more expensive and the operation is more complicated. How to develop a prosthesis with simple operation and low cost is a problem to be solved at present; at the same time, reports of prosthesis-related complications are common, among which prosthesis sinking is the most common prosthesis-related Complications, how to avoid these complications is also one of the problems to be solved in prosthesis design; in addition, the commonly used prosthesis specifications are designed according to European and American human anatomy standards, which makes it impossible for some patients to use the most suitable prosthesis. In fact, there is a high mismatch rate between the common cervical disc prosthesis and the anatomical parameters of the Chinese cervical spine.

Contents of the invention

In order to overcome the deficiencies of the existing technology, the present invention aims to design a 3D printed artificial cervical disc prosthesis, in order to solve the current prosthetic-related complications after cervical disc replacement, such as prosthesis loosening and displacement, prosthesis under the prosthesis, etc. Shen, heterotopic ossification and spontaneous fusion, kyphosis of the replaced segment, loss of segmental mobility, etc.

In order to solve the above problems, the technical solution adopted in the present invention is as follows: a 3D printed artificial cervical disc prosthesis, which is characterized in that it includes an upper endplate of the prosthesis, a lower endplate of the prosthesis, and The nucleus pulposus of the prosthesis between the endplates of the lower body is mutually matched and connected; the upper surface of the upper endplate of the prosthesis is provided with a first microporous surface, and the first microporous surface is distributed with first inverted Teeth; the lower surface of the lower end plate of the prosthesis is provided with a second microhole surface, and second inverted teeth are distributed on the second microhole surface; the prosthesis nucleus pulposus includes an elliptical base.

Further, the upper surface of the base of the nucleus pulposus of the prosthesis is provided with a convex surface, and the lower surface of the upper endplate of the prosthesis is provided with a concave surface matching the convex surface.

Further, the circumference of the convex surface on the upper surface of the base is provided with a ring groove.

Further, the convex surface and the concave surface are all spherical structures, and the apex of the convex surface is not at the center of the base.

Further, the lower surface of the upper end plate of the prosthesis is provided with a convex ring, and the concave surface is located in the inner ring of the convex ring.

Further, first side grooves are distributed on both sides of the first micropore surface on the upper endplate of the prosthesis, and second side grooves are distributed on both sides of the second micropore surface on the lower endplate of the prosthesis. The cross sections of the side groove and the second side groove are arc-shaped structures.

Further, the upper surface of the lower endplate of the prosthesis is symmetrically provided with keys, and the side of the nucleus pulposus of the prosthesis is provided with a fixing groove that cooperates with the keys, and the upper endplate of the prosthesis and The fixing slot is matched with a card slot.

Further, both the upper endplate of the prosthesis and the lower endplate of the prosthesis include the outer surface of the prosthesis and the articular surface, and the two are fitted together.

Further, the overall shape of the upper endplate of the prosthesis and the lower endplate of the prosthesis are rectangular structures with rounded corners.

Further, the 3D printed artificial cervical disc prosthesis has a height of 5-8 mm, a coronal diameter of 12-16 mm in cross section, and a sagittal diameter of 10-14 mm.

A 3D printed cervical intervertebral disc prosthesis, including the upper endplate of the prosthesis, the nucleus pulposus of the prosthesis, and the lower endplate of the prosthesis, with 6 inverted teeth evenly distributed on the surfaces of the upper and lower endplates of the prosthesis, and the prosthetic pulp The nucleus is fixed on the protrusion of the articular surface of the endplate under the prosthesis; the front end is defined as the front end after the cervical intervertebral disc prosthesis is fully assembled, and the rear end is defined as the rear end.

Compared with the artificial cervical intervertebral disc commonly used in clinical practice, this device has the following advantages:

(1) This device is designed through the reverse reverse technology, and it is a completely bionic design. In actual implementation, the three-dimensional anatomical shape of the endplate of the prosthesis and the endplate of the vertebral body is completely fitted, and there is almost no need to grind up and down when implanting the prosthesis. The endplate relatively preserves the integrity of the vertebral endplate.

(2) The device can be rapidly manufactured by 3D printing technology, and in practical application, the implantation process can be simplified, the operation time can be shortened, and the operation safety can be improved.

(3) This device optimizes the design of the inverted tooth in combination with the characteristics of the endplate thickness and bone density distribution of the cervical spine. While achieving immediate fixation, it is convenient for intraoperative adjustment of the prosthesis position and necessary long-term revision.

(4) This device is designed with a unique ball-and-socket joint. The center of the prosthetic nucleus is located in front of the lower endplate of the prosthesis, and a certain degree of forward and backward translation is allowed at its fixed position. It has a movable instantaneous center of rotation, which can resist Axial load can also allow translation, flexion/extension, lateral bending and axial rotation, which is more in line with normal physiological movements.

(5) The surface material of the upper and lower endplates of the device is TC4 (EBM), and it is designed with a honeycomb microporous structure, which is conducive to bone growth after implantation; at the same time, the joints of the upper and lower endplates of the prosthesis The surface is cobalt-chromium-molybdenum high-polish coating, and the core material is UHMW-PE, which has good wear resistance and corrosion resistance.

Description of drawings

Figure 1 is a schematic diagram of the overall structure of the present invention.

Fig. 2 is a schematic exploded view of the structure of the present invention.

Fig. 3 is a schematic diagram of the structure of the upper endplate of the prosthesis.

Fig. 4 is a schematic diagram of the structure of the lower endplate of the prosthesis.

Fig. 5 is six views of the present invention, wherein (a) to (f) are left view, front view, right view, rear view, top view and bottom view respectively.

The symbols in the figure represent: 1—the lower endplate of the prosthesis, 2—the upper endplate of the prosthesis, 3—the nucleus pulposus of the prosthesis, 11—the second microhole surface, 12—the key, 13—the second inverted tooth, 14— Second side groove, 21—first microporous surface, 22—first inverted tooth, 23—first side groove, 24—card groove, 25—convex ring, 26—concave surface, 31—convex surface, 32—ring groove, 33—fixing groove, 34—base.

Detailed ways

As shown in Figures 1 to 5, the present invention discloses a 3D printed artificial cervical intervertebral disc prosthesis, including an upper endplate 2 of the prosthesis, a lower endplate 1 of the prosthesis, and The prosthetic nucleus pulposus 3 between the end plates 1; the upper surface of the end plate 2 of the prosthesis is provided with a first microporous surface 21, and first inverted teeth 22 are distributed on the first microporous surface 21; The lower surface of the lower endplate 1 of the prosthesis is provided with a second microporous surface 11 , and second inverted teeth 13 are distributed on the second microporous surface 11 ; the prosthetic nucleus pulposus 3 includes an oval base 34 . First side grooves 23 are distributed on both sides of the first microporous surface 21 on the upper endplate 2 of the prosthesis, and second side grooves 14 are distributed on both sides of the second microporous surface 11 on the lower endplate 1 of the prosthesis. The cross sections of the side groove 23 and the second side groove 14 are arc-shaped.

The prosthesis of the present invention is composed of a prosthesis upper end plate 2, a prosthesis lower end plate 1 and a prosthesis nucleus pulposus 3, wherein the prosthesis upper end plate 2 and the prosthesis lower end plate 1 are respectively composed of corresponding prosthesis The outer surface and the articular surface are two parts fitted together. The first microporous surface 21 and the second microporous surface 11 are located on the outer surface of the prosthesis. In this embodiment, as a preferred solution, the combined height of the entire prosthesis is 6.8 mm, the coronal diameter on the transverse section is 15 mm, and the sagittal diameter is 13 mm.

As shown in Figures 2 and 4, the upper surface of the upper endplate 2 of the prosthesis, that is, the outer surface of the prosthesis is an individualized component obtained by reverse engineering 3D printing, and its three-dimensional anatomical shape is consistent with the upper vertebral body of the implanted segment The lower endplate is fully fitted, and the material is titanium alloy TC4 (electron beam welding EBM). The surface is provided with a first microporous surface 21, and honeycomb micropores are distributed on the first microporous surface 21; this structure is bone Growth provides long-term stability, is beneficial to bone ingrowth, and improves osteogenic activity; at the same time, three groups of first inverted teeth 22 are distributed on the first microporous surface 21, two for each group, and the first teeth are adjusted individually. The distribution position and shape of the barbed teeth 22 simulate the hook-vertebral joint as much as possible to provide immediate fixation; in this embodiment, the barbed teeth are arc-shaped or hook-shaped. The articular surface of the upper endplate 2 of the prosthesis, its three-dimensional anatomical structure fully accommodates the upper surface components of the upper endplate 2 of the prosthesis, and can be fitted into a stable upper endplate 2 of the prosthesis; A concave surface 26 is provided on the surface, that is, the articular surface, and a ring of convex rings 25 is provided on the outer circumference of the concave surface 26 . Wherein, the protrusion height of the convex ring 25 relative to the articular surface is 0.5 mm to accommodate the prosthetic nucleus pulposus 3, and the cross section of the concave surface 26 is an elliptical structure with a sagittal diameter of 7.8 mm and a coronal diameter of 10.9 mm. The depth of the apex of the concave surface 26 relative to the convex ring 25 is 1.3 mm, and the distance from the center of the concave surface 26 to the front end of the prosthesis is 5.5 mm, and the distance to the rear end of the prosthesis is 7.5 mm, matching the nucleus pulposus 3 of the prosthesis. The front end and rear end of the prosthesis here are defined as the front and rear of the prosthesis after it is fully assembled, and the direction is parallel to the first side groove 23 and the second side groove 14, that is, the top view (e) shown in Figure 5 Below is the front end. Both sides of the upper end plate 2 of the prosthesis are symmetrically provided with draw-in grooves 24, which are provided for matching implantation equipment.

The structure of the prosthetic nucleus pulposus 3 is as shown in Figure 2, the prosthetic nucleus pulposus 3 is made up of a base 34 and a convex surface 31 arranged on the base 34, the circumference of the convex surface 31 is provided with a ring groove 32; in this embodiment, the convex surface 31 , The concave surface 26 is spherical structure. On both sides of the middle part of the base 34, a slot 24 with a width of 2.5 mm and a depth of 3 mm is symmetrically provided. On the upper surface of the lower end plate 1 of the prosthesis, a key 12 is symmetrically arranged. The key 12 is a columnar or L-shaped structure, and the key 12 Extend into the draw-in groove 24 to limit the position of the prosthetic nucleus pulposus 3; the base 34 is 1.8mm high, its cross-sectional coronal diameter is 14mm, and the loss-of-shape diameter is 12mm; the apex of the prosthetic nucleus pulposus 3 convex surface 31 is relative to The base 34 is 2 mm high, and the convex position matches the concave surface 26 of the articular surface of the upper endplate 2 of the prosthesis. It is an eccentric structure, that is, the apex of the convex surface 31 is not at the center of the base 34. This structure is conducive to maintaining replacement The physiological curvature of the segment and provide an instantaneous center of activity, which can not only resist the axial load, but also allow translation, flexion/extension, lateral bending and axial rotation, which is more in line with normal physiological movements.

The prosthetic outer surface 102 of the prosthetic lower endplate 1 is a personalized component obtained through reverse reverse engineering 3D printing. Its three-dimensional anatomical structure fits perfectly with the lower vertebral upper endplate of the replacement segment. The material is TC4 (EBM ), its surface also has the micropore and inverted tooth structure consistent with the design of the upper endplate 2 of the prosthesis, and its working principle is the same. The three-dimensional anatomical structure of the articular surface 101 of the lower endplate 1 of the prosthesis completely accommodates the outer surface of the lower endplate 1 of the prosthesis, and fits with it to form a stable lower endplate 1 of the prosthesis. The material of the articular surface is cobalt-chromium-molybdenum alloy, and there is a key 12 with a width of 1 mm and a height of 2 mm in the middle of the left and right sides of the articular surface, which matches with the prosthetic nucleus pulposus 3 and extends into the fixing groove 33 of the prosthetic nucleus pulposus 3. There is a clearance fit between the groove and the prosthetic nucleus pulposus 3, and a certain degree of forward and backward translation is allowed.

Implementation example 1

The 3D printed artificial cervical intervertebral disc includes the upper and lower endplates of the prosthesis and the nucleus pulposus that cooperate with each other. The upper and lower endplates of the prosthesis are respectively fitted with the corresponding outer surface of the prosthesis and the articular surface. The prosthesis is 6.8mm high, with a coronal diameter of 15mm and a loss-of-shape diameter of 13mm in cross-section.

(1) The upper and lower endplates of the upper endplate of the prosthesis are individualized components obtained through reverse engineering 3D printing. Its three-dimensional anatomical shape fits perfectly with the lower endplate of the upper vertebral body of the implanted segment. The material is TC4 (EBM) , there are many honeycomb micropores on the surface, which is beneficial to bone growth and provides long-term stability. At the same time, three groups of inverted teeth are distributed, each group has two pieces, and the distribution of inverted teeth is adjusted individually to simulate the hook vertebral joint as much as possible. to provide immediate fixation.

(2) The articular surface component of the upper endplate of the prosthesis, its three-dimensional anatomical structure completely accommodates the upper surface component of the upper endplate of the prosthesis, and can be fitted into a stable upper endplate of the prosthesis; the articular surface of the upper endplate of the prosthesis has a concave surface , the convex edge of the concave surface is 0.5mm to accommodate the prosthetic nucleus pulposus. The front end of the body is 5.5mm, and the distance from the back end of the prosthesis is 7.5mm, which matches the nucleus pulposus of the prosthesis. The material of this component is cobalt-chromium-molybdenum alloy, and the concave surface is highly polished coating to improve wear resistance.

(3) The complete upper endplate of the prosthesis is formed by combining the above 1) and 2) components. There is a small absence on the left and right sides of the upper end plate of the prosthesis, which is provided for the implanted equipment that matches the device.

(4) The nucleus pulposus of the prosthesis is made of UHMWPE, which is composed of an oval base and protrusions on it. There is a gap of 2.5 mm in width and 3 mm in depth on both sides of the base, which can be articulated with the endplate of the prosthesis. The columnar protrusions on the surface cooperate to limit the position of the nucleus pulposus; the height of the base is 1.8mm, the coronal diameter of the cross section is 14mm, and the shape diameter is 12mm; The concave surface of the articular surface of the endplate cooperates and presents an eccentric structure, which is beneficial to maintain the physiological curvature of the replacement segment, and provides an instantaneous center of activity, which can not only resist the axial load, but also allow translation, flexion/extension, Side bending and axial rotation are more in line with normal physiological movements.

(5) The lower surface component of the lower endplate of the prosthesis is a personalized component obtained by reverse engineering 3D printing. Its three-dimensional anatomical structure fits perfectly with the upper endplate of the lower vertebral body of the replacement segment. The material is TC4 (EBM) , its surface also has the micropore and inverted tooth structure consistent with the design of the upper endplate of the prosthesis, and its working principle is the same.

(6) The articular surface component of the lower endplate of the prosthesis, whose three-dimensional anatomical structure fully accommodates the lower surface component of the lower endplate of the prosthesis, and fits it into a stable lower endplate of the prosthesis. The material of this component is cobalt-chromium-molybdenum alloy, and there is a columnar protrusion with a width of 1mm and a height of 2mm in the middle of the left and right sides of the articular surface, which matches with the nucleus pulposus of the prosthesis, and does not completely lock the nucleus pulposus of the prosthesis, allowing a certain degree of forward and backward panning activity.

(7) The complete upper endplate of the prosthesis is formed by combining the above 5) and 6) components. The specific combined parameters and three-dimensional shapes of the upper and lower endplate surface components and articular surface components of the prosthesis can be described with reference to the corresponding drawings. It will be apparent to those skilled in the art that the invention is not limited to the details of the above-described exemplary embodiments, but that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Accordingly, the embodiments should be regarded in all points of view as exemplary and not restrictive, the scope of the invention being defined by the appended claims rather than the foregoing description, and it is therefore intended that the scope of the invention be defined by the appended claims rather than by the foregoing description. All changes within the meaning and range of equivalents of the elements are embraced in the present invention. Any reference sign in a claim should not be construed as limiting the claim concerned.

In addition, it should be understood that although this specification is described according to implementation modes, not each implementation mode only contains an independent technical solution, and this description in the specification is only for clarity, and those skilled in the art should take the specification as a whole , the technical solutions in the various embodiments can also be properly combined to form other implementations that can be understood by those skilled in the art.

Claims (10)

1. a kind of 3D printing cervical artificial disc prosthese, which is characterized in that including soleplate on prosthese（2）, soleplate under prosthese（1）With And it is arranged on soleplate on prosthese（2）, soleplate under prosthese（1）Between prosthetic nuclei（3）；Soleplate on the prosthese（2）It is upper Surface is provided with the first micropore face（21）, the first micropore face（21）On the first pawl is distributed with（22）；Soleplate under the prosthese （1）Lower surface be provided with the second micropore face（11）, the second micropore face（11）On the second pawl is distributed with（13）；The prosthese Nucleus pulposus（3）Include the substrate of ellipse（34）.

2. 3D printing cervical artificial disc prosthese as described in claim 1, which is characterized in that the prosthetic nuclei（3）'s Substrate（34）Upper surface be provided with convex surface（31）, soleplate on the prosthese（2）Lower surface be provided with and the convex surface （31）The concave surface of cooperation（26）.

3. 3D printing cervical artificial disc prosthese as claimed in claim 2, which is characterized in that the substrate（34）Upper surface Upper convex surface（31）Circumference be provided with a ring slot（32）.

4. 3D printing cervical artificial disc prosthese as claimed in claim 2, which is characterized in that the convex surface（31）, concave surface （26）It is spherical structure, convex surface（31）Apex not in the substrate（34）Center.

5. 3D printing cervical artificial disc prosthese as claimed in claim 2, which is characterized in that soleplate on the prosthese（2） Lower surface be provided with bulge loop（25）, the concave surface（26）Positioned at bulge loop（25）Inner ring in.

6. 3D printing cervical artificial disc prosthese as described in claim 1, which is characterized in that soleplate on the prosthese（2） Upper first micropore face（21）Both sides the first side slot is distributed with（23）, soleplate under prosthese（1）Upper second micropore face（11）Both sides The second side slot is distributed with（14）, the first side slot（23）, the second side slot（14）Cross section be arcuate structure.

7. 3D printing cervical artificial disc prosthese as described in claim 1, which is characterized in that soleplate under the prosthese（1） Upper surface on be symmetrically arranged with card key（12）, the prosthetic nuclei（3）Side be provided with and the card key（12）Cooperation Fixing groove（33）.

8. 3D printing cervical artificial disc prosthese as described in claim 1, which is characterized in that soleplate on the prosthese（2）、 Soleplate under prosthese（1）Include prosthese outer surface and articular surface, the two is entrenched togather.

9. 3D printing cervical artificial disc prosthese as described in claim 1, which is characterized in that soleplate on the prosthese（2）、 Soleplate under prosthese（1）Monnolithic case be round rectangle structure.

10. 3D printing cervical artificial disc prosthese as described in claim 1, which is characterized in that the artificial neck of the 3D printing Intervertebral disk prosthesis height is 5~8mm, and the coronal footpath on cross section is 12~16mm, and sagittal diameter is 10~14mm.