Artificial cervical intervertebral disc with ultrahigh activity type chamfering U-shaped structure

Abstract

The invention provides an artificial cervical intervertebral disc with an ultrahigh activity type chamfering U-shaped structure. The artificial cervical intervertebral disc comprises an artificial cervical intervertebral disc body which is prepared from titanium alloy. The artificial cervical intervertebral disc is characterized in that the part in which an upper end plate and the lower end plate of the artificial cervical intervertebral disc body is of a chamfering reversed U-shaped noncontact elastic structure; the physiological curvature of the upper end plate and the lower end plate protruding towards of the artificial cervical intervertebral disc body is 3 to 6 degrees; the front ends of the upper end plate and the lower end plate are fixed through bolts; the front edges of the upper end plate and the lower end plate have arc-shaped appearances similar to human vertebration; two rows of reversed teeth for stopping backing are respectively arranged in the outer surfaces of the upper end plate and the lower end plate; the elasticity modulus of the artificial cervical intervertebral disc body is 45 to 80GPa, and the yield strength is more than 620MPa. The artificial cervical intervertebral disc meets the requirements on long service life and fatigue resistance; the mobility of operated sections of a patient can be 80 to 100% of that of normal human body.

Description

technical field [0001] The invention relates to an artificial cervical intervertebral disc, in particular to an artificial cervical intervertebral disc with a cut angle Ω-shaped structure with ultra-high mobility. Background technique [0002] Artificial cervical disc replacement can decompress the spinal cord and keep it stable while ensuring the physiological activity of the surgical segment, which is more in line with the biomechanical characteristics of cervical spine activities. [0003] Although the Z-Brace dynamic fusion device uses a Z-shaped elastic connecting rod, which can move slightly, and has several rows of inverted teeth on the upper and lower sides of the end surface to achieve the purpose of cooperating with the normal intervertebral disc of the patient, there are still The following main deficiencies: First, the range of motion of the Z-Brace dynamic fusion device is only 10% to 30% for forward flexion, lateral flexion, and torsion, and only 20% to 40% f...

AI Technical Summary

Problems solved by technology

[0003]Z-Brace dynamic fusion device, although this solution uses a Z-shaped elastic connecting rod, which can be moved slightly, and there are several rows of inverted teeth on the upper and lower sides of the end surface and other measures To achieve the purpose of cooperating with the normal intervertebral disc of the patient, but there are still the following main shortcomings: First, the Z-Brace dynamic fusion cage has only 10% to 30% of the range of motion for forward flexion, lateral flexion, and twisting, and only 10% for backward flexion. 20% to 40%; the second is that the stability of the Z-Brace dynamic fusion device is too dependent on the anti-recession teeth, and there are no bolts to ensure the upper and lower stability of the intervertebral disc and the prosthesis when it is immediately fixed with the patient's normal intervertebral disc

[0004] Chinese patent application 200620112142 discloses the "shrapnel type artificial intervertebral disc", although the scheme adopts a horseshoe-shaped shrapnel, and a plurality of inverted discs are respectively arranged on the upper and lower sides of the shrapnel. hook and other measures to achieve the purpose of cooperating with the patient's normal intervertebral disc, but there are still the following main shortcomings: First, from the perspective of biophysics, it cannot well meet the normal physiological curvature of C5-C6 lordosis3 ~6o; second, the lack of precision design means for the curvature and height, so that the implanted prosthesis cannot restore and maintain the height of the intervertebral space and the stability of the segment; third, the existing integrated shrapnel artificial neck After intervertebral disc implantation, the range of motion of the segment is quite different from that of the normal cervical segment, and the motion function of the normal cervical segment cannot be restored well.

[0005] Chinese patent application 201310223928.1 discloses "an integrated artificial cervical intervertebral disc prosthesis with high mobility", and Chinese patent application 201310217563.1 discloses "a herringbone-shaped The Ω-shaped artificial cervical intervertebral disc implant prosthesis with two-way anti-retrograde teeth", Chinese patent application 201310217243.6 discloses "an Ω-shaped artificial cervical intervertebral disc implant prosthesis with diamond-shaped two-way anti-retrograde teeth", Chinese patent application 200920211398 publication The "Medical Orthopedic Cervical Intervertebral Space Dynamic Stabilization Device", although these schemes all use Ω-shaped non-contact elastic structures, and symmetrically set inverted teeth on the outer surface of the upper and lower end plates to achieve the purpose of cooperating with the normal intervertebral disc of the patient. , but there are still the following deficiencies: First, the lateral flexion range of the existing integrated artificial cervical disc implant prosthesis is only 30% to 60%, and the torsional range of motion is only 10% to 40%; The stability of the artificial cervical intervertebral disc implanted prosthesis is too dependent on the anti-recession teeth, and there are no bolts to ensure the up and down stability of the intervertebral disc and the prosthesis when it is immediately fixed with the patient's normal intervertebral disc

[0006] U.S. Patent Application 7794465B2 discloses a kind of "artificial cervical intervertebral disc and related implantation device and method" (see United States Patent 7794465B2 "Artificial spinal discs and associated implantation instruments and methods”), although the scheme adopts the combination mode of ball-socket joint connection, flexion and extension, lateral bending and axial torsion can all meet the requirements of various functional activities of the human body, and there are two rows of inverted teeth and bolts on the outer surface of the upper and lower end plates To achieve the purpose of cooperating with the normal intervertebral disc of the patient, but there are still the following disadvantages: first, the structure is cumbersome and the operation is relatively complicated, which is easy to cause heterotopic ossification; second, when the ball-socket of the prosthesis moves, it is easy to produce wear particles , causing inflammation; third, the front edge of the artificial cervical intervertebral disc and the end face of the bolt hole are the same arc surface, which does not consider the specificity of the human body, and it is easy to compress the nerve and blood vessel tissue, so the distance should be set; Elastic structural support, relying too much on the high and long rows of teeth, increases the difficulty of surgery and the pain of patients, and easily compresses nerves, causing complications

[0007] In summary, although the materials and shapes of fusion cages and integrated artificial cervical intervertebral discs are different, these prostheses generally have the following disadvantages: prosthesis flexion, The range of torsion and lateral flexion is difficult to reach 60% of the normal range of motion of the human body, and the voluntary fusion rate is high, which makes it difficult to meet the needs of normal human motion; at the same time, there are no bolts to ensure the up and down stability of the intervertebral disc and the prosthesis when it is immediately fixed with the patient's normal intervertebral disc

Common prostheses with multi-body structures generally have the following disadvantages: cumbersome structure, relatively complicated surgery, and easy to cause heterotopic ossification; poor fatigue and wear resistance, fatigue fracture, and fatigue wear can easily lead to wear particles on the prosthesis, which is prone to Cause aseptic bone resorption, leading to failure of prosthetic replacement, prone to postoperative complications

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