CN211271424U - Allogeneic cortical cancellous bone embedded cervical interbody fusion cage - Google Patents

Abstract

The utility model provides an allogeneic cortical cancellous bone embedded cervical interbody fusion cage, which is an integral structure formed by embedding a front structure with dovetail protrusions and a rear structure with dovetail grooves; a through hole penetrating through the fusion cage is formed in the middle of the side surface of the front structure and used for inserting a bone rod made of the same material as the front structure, and 3-5 rows of pyramid-shaped teeth are correspondingly formed on the upper surface and the lower surface of the fusion cage in the front position respectively; grooves are correspondingly formed in the upper surface and the lower surface of the rear structure along the width direction of the rear structure. 3-5 rows of pyramid-shaped teeth are arranged on the upper surface and the lower surface of the front structure of the fusion cage, so that the displacement and the slippage after the implantation can be avoided, and the rapid stabilization between the fusion cage and the upper and lower adjacent cervical vertebra bodies can be realized; drilling a through hole penetrating the whole in the front structure, and inserting a cylindrical allogeneic cortical bone bar into the through hole, so that the embedding strength of the front part and the rear part can be enhanced.

Description

Allogeneic cortical cancellous bone embedded cervical interbody fusion cage

Technical Field

The utility model belongs to the field of medical instrument implants, in particular to an allogeneic spongy bone embedded cervical interbody fusion cage.

Background

Nerve compression, spinal stenosis and the like caused by cervical disc herniation and degenerative changes are common cervical vertebra diseases, and if physical or pharmaceutical treatment cannot relieve neck or/and upper limb pain caused by nerve compression, cervical disc resection and fusion are generally required. Among them, discectomy is "cutting out an intervertebral disc" as the name suggests, and any segment of the intervertebral disc from the neck (cervical spine) to the back waist (lumbar spine) along the spine can be cut out. After the disc is removed, the space between the vertebral bodies is empty. To prevent collapse and friction of the vertebral bodies, bone implant spacers (also known as fusion cages) are inserted to fill the open disc space. This implant plays the role of a bridge to achieve spinal fusion. The bone implant and vertebral body are also held in place by metal plates and screws.

At present, the medical clinic mainly uses polyether ether ketone (PEEK) materials or solid titanium alloy materials to manufacture the cervical vertebra interbody fusion cage. However, the cervical interbody cage made of these materials has no osteogenesis effect and cannot be absorbed by human body in clinical application, so there are many limitations: although PEEK has better biocompatibility and mechanical properties similar to those of bone tissues, the fusion cage made of PEEK material is only wrapped by newly formed fibrous connective tissues after being implanted into a body, and is difficult to be tightly combined with surrounding bone tissues (namely, the bonding strength of the bone-fusion cage interface is insufficient), so that the fusion cage is easy to loosen and even fails in fusion. The titanium alloy material also has good biocompatibility and can promote the adhesion of bone cells on the surface of the titanium alloy material. However, the elastic modulus (101-114GPa) is much higher than that of human skeleton (cortical bone about 3.5-20GPa), which can cause stress shielding, so that the vertebral body is in a low stress state, and osteoporosis and/or degenerative changes of adjacent intervertebral discs can be caused.

In order to solve the problems, the allogeneic bone material which has the most similar biological and mechanical properties with human bones and can be completely replaced by the human bones in a creeping way becomes a better material option for manufacturing the cervical interbody fusion cage.

Bone grafting techniques have been widely used for repairing bones and joints for over 200 years. During the first 80 years of bone grafting, the grafting material is mainly from the autogenous body, and the most common materials are ilium and fibula, which often cause secondary trauma and are limited by source and amount. Therefore, the allograft bone grafting technology is gradually explored and developed. The development of allogeneic bone transplantation relieves the pain and risk of secondary trauma of patients, enriches the sources and the dosage of bones for transplantation, accumulates long-term experience of nearly 120 years, improves the surgical operation skills of allogeneic bone transplantation day by day, reduces the limit of disease transmission and immunological rejection, and has clinical effect close to autologous bone transplantation.

Disclosure of Invention

An object of the utility model is to provide a accord with human cervical vertebra anatomical structure, can realize quick, firm osseointegrated allogeneic skin cancellous bone gomphosis formula cervical vertebra interbody fusion cage with upper and lower adjacent cervical vertebra centrum after the implantation.

An allogeneic cortical cancellous bone embedded cervical interbody fusion cage is an integral structure formed by embedding a front structure with dovetail protrusions and a rear structure with dovetail grooves; a through hole penetrating through the fusion cage is formed in the middle of the side surface of the front structure and used for inserting a bone rod made of the same material as the front structure; the upper surface and the lower surface of the fusion device positioned at the front part are respectively and correspondingly provided with 3-5 rows of pyramid-shaped teeth; the upper surface and the lower surface of the rear structure are correspondingly provided with grooves along the width direction.

Preferably, the cross section of the fusion cage is in a ladder-like structure.

Preferably, the sagittal aspect of the cage is parallel, antero-convex or convex.

Preferably, the fusion device material is allogeneic bone.

Preferably, the front structure is made of allogeneic cortical bone blocks, and the rear structure is made of allogeneic cancellous bone blocks.

Preferably, the cross-sectional structure of the groove is a quasi-semicircular structure, and the groove is arranged close to the deepest position of the dovetail groove; the pyramidal teeth are arranged on the upper and lower surfaces of the front structure and at the dovetail joint positions of the front structure and the rear structure in the width direction of the rear structure.

Preferably, the volume of the allogeneic cortical bone pieces in the anterior structure accounts for 15% -40% of the total cage volume, and the allogeneic cancellous bone pieces in the posterior structure accounts for 60% -85% of the total cage volume.

Preferably, the anterior convexity has an anterior convexity angle in the range of 5-10 degrees and the radius of the arc of the upper surface of the upper convexity is 12-16 mm.

Preferably, the unilateral length and the tooth height of the pyramid-shaped teeth are 0.5-1.0 mm; the diameter of the cylindrical cortical bone rod of the through hole in the fusion device is 1.5-2.5 mm; the width of the fusion cage is 13-15mm, the depth is 10-13mm, and the height is 5-12 mm.

In order to achieve the above purpose, the utility model adopts the technical scheme that: this integration ware has the forked tail protruding and is located the allogeneic cancellous bone piece at rear portion and has the mutual gomphosis of forked tail recess by being located anterior allogeneic cortical bone piece and form, drills out in front surface middle part and runs through holistic perforating hole, interpolates the allogeneic cortical bone stick of cylinder form to the gomphosis intensity of two parts around strengthening. 3-5 rows of pyramidal teeth are arranged in front of the upper and lower surfaces of the fusion device to avoid displacement and slippage after implantation. Semicircular sunken grooves are processed on the upper surface and the lower surface of the rear part of the allogeneic cancellous bone dovetail sunken parts behind the pyramidal teeth along the left-right direction, so that blood vessels can grow more easily.

Preferably, the cervical interbody fusion cage material is an allogeneic bone, including: allogeneic cortical bone pieces and allogeneic cancellous bone pieces.

The volume of the anterior allograft cortical bone pieces is 15% -40% of the total cage volume, providing sufficient compressive strength to the cage and allowing for a knock-in approach into the disc space.

The allogeneic cancellous bone blocks at the rear part account for 60-85% of the volume of the whole fusion device, the porous spatial structure of the fusion device together with the semicircular grooves at the upper and lower surfaces allows the implant grown in the blood vessel to be quickly absorbed, and the blood supply is improved to promote faster fusion.

The cross section of the fusion cage is in a trapezoid-like shape, and the sagittal plane shape has three types: the parallel shape, the front convex shape and the upper convex shape are beneficial to maintaining the physiological curvature of the cervical vertebra under different disease conditions. The range of the front convex angle of the front convex is 5-10 degrees, and the radius of the circular arc of the upper surface of the upper convex is 12-16 mm.

The unilateral length and the tooth height of the pyramid-shaped tooth are 0.5-1.0 mm.

The diameter of the cylindrical cortical bone rod to be inserted into the through hole in the middle of the fusion device is 1.5-2.5 mm.

The width of the fusion cage is 13-15mm, the depth is 10-13mm, and the height is 5-12 mm.

The preparation method comprises the following steps:

1) and (3) precisely machining to prepare allogeneic cortical bone blocks and allogeneic cancellous bone blocks.

2) The matched 2 bone pieces are embedded together in height.

3) And preparing a cylindrical cortical bone bar by precision machining, and drilling a through hole.

4) The cylindrical cortical bone rod is inserted into the through hole.

5) And (3) precisely machining and preparing the pyramid-shaped teeth and the semicircular grooves on the upper surface and the lower surface of the fusion device.

The application has the advantages that: 3-5 rows of pyramid-shaped teeth are arranged on the upper and lower surfaces of the fusion device, so that the displacement and slippage after implantation can be avoided, and the rapid stabilization between the fusion device and the upper and lower adjacent cervical vertebra bodies can be realized; a through hole penetrating the whole is drilled on the front structure, and a cylindrical allogeneic cortical bone bar is inserted in the through hole, so that the embedding strength of the front part and the rear part can be enhanced; the allogeneic cancellous bone blocks at the back part account for 60 to 85 percent of the volume of the whole fusion cage, and the porous spatial structure of the fusion cage together with the semicircular grooves arranged on the upper and lower surfaces is easy for blood vessels to grow in, thereby being beneficial to realizing rapid fusion and stability of the implanted fusion cage and the upper and lower adjacent cervical vertebra bodies; in addition, the cross section of the fusion cage is in a trapezoid-like shape, and the sagittal plane is provided with three forms: the parallel shape, the front convex shape and the upper convex shape are beneficial to maintaining the physiological curvature of the cervical vertebra under different disease conditions.

Drawings

FIG. 1 is a schematic structural view of a fusion cage according to the present application;

FIG. 2 is a schematic view of a first sagittal shape of a cage of the present application;

FIG. 3 is a schematic view of a second sagittal view of a cage of the present application;

FIG. 4 is a schematic view of a third sagittal view of a cage of the present application;

FIG. 5 is a top view of FIG. 1;

fig. 6 is a schematic diagram of the results of the fusion cage of the present application in a particular use.

Detailed Description

The present application is further described with reference to the accompanying drawings:

in the description of the present application, it is to be understood that if there is an orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", etc. based on the orientation or positional relationship shown in the drawings, it is only for convenience of description and simplification of the description, but it is not intended to indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and not to be construed as limiting the present application, and the specific meaning of the terms described above will be understood by those skilled in the art according to the specific circumstances.

Examples

The utility model provides an allogenic skin cancellous bone gomphosis formula cervical vertebra interbody fusion cage, fusion cage 1 includes anterior structure 11 and rear structure 12, anterior structure has dovetail protrusion 111, rear structure 12 has the forked tail recess with dovetail protrusion assorted, passes through dovetail protrusion and forked tail recess looks gomphosis with anterior structure 11 and rear structure 12 and forms the fusion cage 1 of an overall structure. A through hole 13 penetrating the fusion cage is formed in the middle of the side surface of the anterior structure 11, a cylindrical bone rod made of the same material as the anterior structure is inserted into the through hole 13, and 4 rows of pyramidal teeth 112 are formed on the upper and lower surfaces of the fusion cage 1 in the anterior position so as to correspond to each other, and as shown in fig. 1, the pyramidal teeth 112 are arranged on the upper and lower surfaces of the anterior structure 11 and at dovetail joint positions of the anterior and posterior structures in the width direction of the posterior structure. The pyramid-shaped teeth 112 are arranged along the left and right direction (width direction) of the fusion cage, so that the displacement and slippage of the fusion cage after being implanted can be avoided; the upper and lower surfaces of the rear structure 12 are correspondingly provided with grooves 121 (i.e., grooves 121) along the width direction thereof (i.e., the left-right direction of the fusion device of fig. 1), which facilitate the ingrowth of blood vessels. The cross-sectional configuration of the groove 121 is semi-circular like and is disposed proximate to the deepest point of the dovetail recess (i.e., dovetail groove) of the aft structure 12. In this embodiment, the fusion device material is allogeneic bone, preferably the front structure 11 material is allogeneic cortical bone, and the rear structure 12 material is allogeneic cancellous bone; the bone rod inserted into the through hole is an allogeneic cortical bone block bone rod. As can be seen from fig. 1, the cross section of the fusion cage is in a ladder-like shape structure. As shown in FIG. 5, the width of the cage in this example is 14.5mm, and the front and rear sides (depth) are 12 mm.

Preferably, the sagittal plane morphology of the fusion cage of the present application is of three types: parallel, antero-convex and convex, the sagittal configuration of the cage shown in fig. 2 is a parallel configuration, the sagittal configuration of the cage shown in fig. 3 is an antero-convex configuration, and the sagittal configuration of the cage shown in fig. 4 is an upper convex configuration. When the sagittal plane configuration of the cage adopts the anterior convex configuration, the anterior convex angle of the anterior convex is in the range of 5-10 degrees. When the sagittal shape of the fusion cage adopts the upward convex shape, the arc radius of the upper surface of the upward convex shape is 12-16 mm.

Preferably, the volume of the allograft cortical bone pieces of the anterior construct is between 15% and 40% of the total cage volume, providing sufficient compressive strength to the cage and allowing knock-in type beating into the disc space. The allogeneic cancellous bone blocks of the rear structure account for 60-85% of the volume of the whole fusion cage.

Preferably, the unilateral length and the tooth height of the pyramid-shaped teeth are 0.5-1.0 mm; the diameter of the cylindrical cortical bone rod to be inserted into the through hole in the middle of the fusion device is 1.5-2.5 mm; the width of the fusion cage is 13-15mm, the depth is 10-13mm, and the height is 5-12 mm.

Claims (9)

1. The utility model provides an allogeneic skin cancellous bone gomphosis formula cervical vertebra interbody fusion cage which characterized in that: the fusion cage is an integral structure formed by embedding a front structure with dovetail protrusions and a rear structure with dovetail grooves; a through hole penetrating through the fusion cage is formed in the middle of the side surface of the front structure and used for inserting a bone rod made of the same material as the front structure; the upper surface and the lower surface of the fusion device positioned at the front part are respectively and correspondingly provided with 3-5 rows of pyramid-shaped teeth; the upper surface and the lower surface of the rear structure are correspondingly provided with grooves along the width direction.

2. The fusion cage according to claim 1, wherein: the cross section of the fusion cage is of a ladder-like structure.

3. The fusion cage according to claim 2, wherein: the sagittal plane of the fusion cage is parallel, anterior convex or upward convex.

4. The fusion cage according to claim 1 or 2 or 3, wherein: the fusion device material adopts allogeneic bone.

5. The fusion cage according to claim 4, wherein: the front structural material adopts allogeneic cortical bone blocks, and the rear structural material adopts allogeneic cancellous bone blocks.

6. The fusion cage according to claim 1 or 2 or 3, wherein: the section structure of the groove is of a quasi-semicircular structure, and the groove is arranged close to the deepest position of the dovetail groove; the pyramidal teeth are arranged on the upper and lower surfaces of the front structure and at the dovetail joint positions of the front structure and the rear structure in the width direction of the rear structure.

7. The cervical fusion cage of claim 5, wherein: the volume of the allogeneic cortical bone blocks of the front structure accounts for 15-40% of the volume of the whole fusion cage, and the allogeneic cancellous bone blocks of the rear structure accounts for 60-85% of the volume of the whole fusion cage.

8. The fusion cage according to claim 3, wherein: the range of the front convex angle of the front convex is 5-10 degrees, and the radius of the circular arc of the upper surface of the upper convex is 12-16 mm.

9. The fusion cage according to claim 1 or 2 or 3, wherein: the unilateral length and tooth height of the pyramid-shaped teeth are 0.5-1.0 mm; the diameter of the cylindrical cortical bone rod of the through hole in the fusion device is 1.5-2.5 mm; the width of the fusion cage is 13-15mm, the depth is 10-13mm, and the height is 5-12 mm.

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