阅读说明：本技术 一种高固定强度可吸收界面螺钉 (Absorbable interface screw with high fixing strength ) 是由 曾晨光 杨习锋 陈诗浩 金振华 周启明 丁雪玲 于 2020-05-28 设计创作，主要内容包括：本发明提供一种高固定强度可吸收界面螺钉,改善现有界面螺钉配方,降低界面螺钉刚性,从而在不改变螺钉固定强度的条件下降低界面螺钉对韧带的切割力,此外,加入诱导骨再生材料,从而使得螺钉降解时间与骨长入时间匹配。本发明一种高固定强度可吸收界面螺钉的技术方案包括：一种高固定强度可吸收界面螺钉,其特征在于,包括PLLA、PL-TMC和羟基磷灰石,三者的配比是PLLA为99％～50％,PL-TMC为1％～50％,羟基磷灰石为0.01％～10％,所述PLLA的分子量为10～100W,所述PL-TMC为PLA与PTMC的共聚物,所述羟基磷灰石的粒径为1nm～5000nm。(The invention provides an absorbable interface screw with high fixing strength, which improves the formula of the existing interface screw, reduces the rigidity of the interface screw, thereby reducing the cutting force of the interface screw on ligaments under the condition of not changing the fixing strength of the screw, and in addition, the invention adds an induced bone regeneration material, thereby matching the degradation time of the screw with the bone ingrowth time. The invention discloses a technical scheme of an absorbable interface screw with high fixing strength, which comprises the following steps: an absorbable interface screw with high fixing strength is characterized by comprising 99-50% of PLLA, 1-50% of PL-TMC and 0.01-10% of hydroxyapatite, wherein the molecular weight of the PLLA is 10-100W, the PL-TMC is a copolymer of PLA and PTMC, and the particle size of the hydroxyapatite is 1-5000 nm.)

1. An absorbable interface screw with high fixing strength is characterized by comprising 99-50% of PLLA, 1-50% of PL-TMC and 0.01-10% of hydroxyapatite, wherein the molecular weight of the PLLA is 10-100W, the PL-TMC is a copolymer of PLA and PTMC, and the particle size of the hydroxyapatite is 1-5000 nm.

2. The high fixation strength absorbable interface screw of claim 1, wherein the molecular weight of the PLLA is 40-80W.

3. The high fixation strength absorbable interface screw of claim 2, wherein the molecular weight of the PLLA is 50-75W.

4. The high fixation strength absorbable interface screw of claim 1, wherein the PLA: the molar content ratio of the PTMC is 99: 1-50: 50.

5. The high fixation strength absorbable interface screw of claim 3, wherein the PLA: the molar content ratio of PTMC is 80: 20-60: 40.

6. The high fixation strength absorbable interface screw of claim 5, wherein the PLA: the molar content ratio of PTMC is 70: 30.

7. The absorbable interface screw of high holding strength of claim 1, wherein the hydroxyapatite has a particle size of 1nm to 100 nm.

8. The absorbable interface screw with high fixation strength as claimed in claim 7, wherein the hydroxyapatite has a particle size of 5-20 nm.

9. The absorbable interface screw with high fixation strength as claimed in claim 1, wherein the ratio of PLLA to PL-TMC is 95-70%, PL-TMC is 1-30%, and hydroxyapatite is 0.1-5%.

10. The absorbable interface screw with high fixation strength as claimed in claim 9, wherein the ratio of PLLA to PL-TMC is 80-70%, PL-TMC is 10-30%, and hydroxyapatite is 1-5%.

Technical Field

The invention relates to the technical field of interface screws, in particular to an absorbable interface screw with high fixing strength.

Background

The fixation strength and creep resistance of the interface screw are particularly important because the interface screw is used in ACL (knee cruciate ligament) reconstruction and serves as a fixation ligament during surgery, and the reciprocating motion of the knee joint causes the interface screw to have a continuous tendency to creep outward. However, the fixing strength and creep resistance of the current interface screw are still insufficient.

The interface screw has the following problems: the interface screw is a hollow conical screw, the head part of the interface screw is thinner, and the interface screw is easy to deform or break under the action of torsion force in the screwing-in process; when the interface screw is screwed in again and the knee joint reciprocates, shearing force is generated on the ligament, so that the ligament is easy to generate fatigue failure; the degradation time of the absorbable interface screw is not matched with the bone ingrowth time, so that the bone density is insufficient, and complications are caused after the operation rehabilitation.

Disclosure of Invention

The invention provides an absorbable interface screw with high fixing strength, which improves the formula of the existing interface screw, reduces the rigidity of the interface screw, thereby reducing the cutting force of the interface screw on ligaments under the condition of not changing the fixing strength of the screw, and in addition, the invention adds an induced bone regeneration material, thereby matching the degradation time of the screw with the bone ingrowth time.

The invention discloses a technical scheme of an absorbable interface screw with high fixing strength, which comprises the following steps:

an absorbable interface screw with high fixing strength is characterized by comprising 99-50% of PLLA, 1-50% of PL-TMC and 0.01-10% of hydroxyapatite, wherein the molecular weight of the PLLA is 10-100W, the PL-TMC is a copolymer of PLA and PTMC, and the particle size of the hydroxyapatite is 1-5000 nm.

Preferably, in the above-mentioned technical solution of the absorbable interface screw with high fixing strength,

the molecular weight of the PLLA is 40-80W.

Preferably, in the above-mentioned technical solution of the absorbable interface screw with high fixing strength,

the molecular weight of the PLLA is 50-75W.

Preferably, in the above-mentioned technical solution of the absorbable interface screw with high fixing strength,

the PLA: the molar content ratio of the PTMC is 99: 1-50: 50.

Preferably, in the above-mentioned technical solution of the absorbable interface screw with high fixing strength,

the PLA: the molar content ratio of PTMC is 80: 20-60: 40.

Preferably, in the above-mentioned technical solution of the absorbable interface screw with high fixing strength,

the PLA: the molar content ratio of PTMC is 70: 30.

Preferably, in the above-mentioned technical solution of the absorbable interface screw with high fixing strength,

the particle size of the hydroxyapatite is 1 nm-100 nm.

Preferably, in the above-mentioned technical solution of the absorbable interface screw with high fixing strength,

the particle size of the hydroxyapatite is 5-20 nm.

Preferably, in the above-mentioned technical solution of the absorbable interface screw with high fixing strength,

the mixture ratio of the three components is that PLLA is 95-70%, PL-TMC is 1-30%, and hydroxyapatite is 0.1-5%.

Preferably, in the above-mentioned technical solution of the absorbable interface screw with high fixing strength,

the mixture ratio of the three is that PLLA is 80-70%, PL-TMC is 10-30%, and hydroxyapatite is 1-5%.

The invention reduces the rigidity of the PLLA and the screwing torque thereof by introducing PL-TMC on the premise of not reducing the fixing strength of the interface screw, and simultaneously ensures the fixing strength of the interface screw by controlling the molecular weight of the PLLA. In addition, a proper amount of hydroxyapatite nanoparticles are introduced, so that the regeneration of bone tissues can be induced, and the bone repair is promoted. It should be noted that the formulation of the present invention is also applicable to other forms of bone screws and nails.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

FIG. 1 is a schematic view of an interface screw.

Detailed Description

The invention provides an absorbable interface screw with high fixing strength, which improves the formula of the existing interface screw, reduces the rigidity of the interface screw, thereby reducing the cutting force of the interface screw on ligaments under the condition of not changing the fixing strength of the screw, and in addition, the invention adds an induced bone regeneration material, thereby matching the degradation time of the screw with the bone ingrowth time.

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The formula of the absorbable interface screw with high fixing strength is PLLA, PL-TMC and hydroxyapatite.

The molecular weight, molar content and particle size of the above components are shown in the table below.

	Molecular weight of PLLA	PL-TMC(LA：TMC)	Particle size of hydroxyapatite
				Range of	10～100W	99:1～50:50	1nm～5000nm
Optimum range	40～80W	80：20～60:40	1nm～100nm
				Optimization of	50～75W	70:30	5～20nm

The proportions of the three components are shown in the following table.

	PLLA	PL-TMC	Particle size of hydroxyapatite
				Range of	99％～50％	1％～50％	0.01％～10％
More preferred range	95％～70％	1％～30％	0.1％～5％
				Optimization of	80％～70％	10％～30％	1％～5％

The following description will be made with reference to an embodiment.

The invention reduces the rigidity of the PLLA and the screwing torque thereof by introducing PL-TMC on the premise of not reducing the fixing strength of the interface screw, and simultaneously ensures the fixing strength of the interface screw by controlling the molecular weight of the PLLA. In addition, a proper amount of hydroxyapatite nanoparticles are introduced, so that the regeneration of bone tissues can be induced, and the bone repair is promoted. It should be noted that the formulation of the present invention is also applicable to other forms of bone screws and nails.

The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.