医用缝合材料检测要点

结论：强度够不够、保持多久、身体怎么反应，是三个核心问题

缝合材料的功能是把组织对合并维持到愈合。围绕这个功能，三个核心问题是：

强度够不够。 线材本身的强度，以及打结之后的强度——打结会降低强度，而临床使用中线总是打结的。

保持多久。 可吸收材料的强度随时间下降，下降的速度要与组织愈合的速度匹配。降解太快组织还没长好，太慢则异物存留时间长。

身体怎么反应。 材料在组织中引起的反应程度，以及降解产物的影响。

分类与项目

「毛细作用」在多股线上要关注，因为毛细作用可能把细菌沿线带入深部组织。

强度的考察

直线拉伸强度。 线材本身的断裂强力。

打结拉伸强度。 打结后的断裂强力，这是临床更相关的指标。

打结强度与直线强度的比值。 反映打结对强度的影响程度。

打结的方式。 不同的打结方式结果不同，应当按规定方式。

线径。 与强度对应的规格。

延伸率。 断裂时的伸长。

「打结强度」是关键指标，因为线在体内总是打结的，直线强度再高，如果打结后强度下降很多，实际的保持能力就不足。

打结性能的考察

打结的安全性。 结是否容易松脱。

打结所需的圈数。 某些材料需要更多圈数才能保证结不松。

结的体积。 影响组织中的异物量和触感。

操作手感。 打结时的顺滑度和手感。

记忆性。 线材是否有形状记忆，影响操作。

「结松脱」是临床的实际风险。 某些光滑的单股材料结的保持力较差，需要更多圈数，产品资料中应当说明推荐的打结方式和圈数。

可吸收材料的降解考察

强度保持曲线。 在模拟体液中随时间的强度变化。这是可吸收缝线的核心数据。

完全吸收时间。 材料完全降解所需的时间。

降解产物。 降解产生的物质及其影响。

降解速度的影响因素。 pH、温度、组织类型都影响降解。

与愈合的匹配。 强度保持期应当覆盖组织愈合所需的时间。

「强度保持曲线」应当给出多个时间点的数据，而不只给「多少天后保持多少」的单点数据——曲线能说明强度下降的过程。

缝合针的考察

带针缝线的针同样重要：

穿刺力。 穿透组织所需的力，影响操作和组织损伤。

针的强度。 弯曲和断裂的抵抗。断针留在体内后果严重。

针尖的锋利度与形状。 影响穿刺和组织损伤。

针体的形状。 弯曲半径和截面形状。

针线连接强度。 线从针上脱落的风险。

表面处理。 影响穿刺的顺滑度。

「针线连接强度」应当验证，因为连接处脱开会导致操作中断，而在深部操作时可能造成麻烦。

生物相容性与组织反应

接触性质。 与组织长期接触（不可吸收）或在体内降解（可吸收）。

项目。 按植入产品的要求确定。

组织反应。 材料在组织中引起的炎症反应程度。

降解产物的影响。 可吸收材料适用。

涂层的影响。 某些缝线有涂层改善操作性，涂层也要评价。

「涂层的评价」容易被忽略，但涂层与组织直接接触且可能脱落。

无菌与包装

无菌。 缝线是无菌产品。

灭菌相容。 特别是可吸收材料，灭菌可能影响降解特性。

包装。 保持线的形状、便于无菌取用、防止打折。

有效期。 可吸收材料的储存稳定性。

「灭菌对可吸收材料的影响」需要验证，因为辐照等方式可能加速材料的降解，影响强度保持曲线。

操作性能的考察

缝线的操作性能影响手术效率和效果：

柔顺性。 线材的柔软程度，影响操作手感。

记忆性。 从包装中取出后是否保持卷曲。

表面摩擦。 通过组织时的顺滑度。

可见性。 在手术视野中的辨识度，某些线有颜色。

包装的取用。 从包装中取出是否顺畅、是否打结。

「记忆性强」的线材操作不便，从包装取出后保持卷曲，需要拉直，增加操作步骤。

规格与标识

规格体系。 线径的规格标注方式。

规格与强度的对应。 每个规格对应的强度要求。

长度。 线的长度。

针的规格。 弧度、长度、截面形状。

标识。 包装上的规格、材质、灭菌、有效期。

颜色编码。 便于快速识别规格。

「颜色编码」在手术中有实际价值，护士需要快速取到正确规格的缝线。

送检准备的建议

提供各规格的样品；说明材料成分与工艺；提供可吸收材料的声称降解特性；说明灭菌方式；准备足够样品（强度试验消耗大）；以及提供配套的针。

常见的不合格原因

打结强度不足。 材料或工艺问题。

线径不符。 规格与实测不符。

降解过快或过慢。 与声称的保持期不符。

针线连接脱开。 连接工艺问题。

针弯曲或断裂。 材料或热处理问题。

灭菌后性能下降。 灭菌与材料不相容。

这六项在缝合材料检测中出现频率较高。

我们的做法

做缝合材料测试时，我们把打结强度作为重点指标并按规定的打结方式操作，因为打结方式的差异会明显影响结果，而结果要有可比性。

对于可吸收材料，强度保持曲线我们建议设多个时间点，在模拟体液和体温条件下做——这组数据是产品临床适用性的直接依据。

带针产品的针线连接强度和针的抗弯抗断是我们会做的项目，因为断针和脱针的后果严重。

如果你有缝合材料需要安排检测，想先理清项目，可以把产品类型和规格发过来一起讨论，或者直接联系：132 4819 8029。能力范围见服务介绍，流程见检测流程，更多内容见知识库。

English version

Conclusion. Sutures approximate tissue and hold it until healing. Three questions follow from that function. Is the strength adequate, covering both the material's strength and its strength once knotted, since knotting reduces strength and clinical use always involves knots. How long does it hold, since absorbable materials lose strength over time and the rate must match tissue healing; degrading too quickly leaves tissue unhealed and too slowly leaves a foreign body in place. And how does the body respond, covering tissue reaction to the material and the effects of degradation products.

Types and items. Non-absorbable monofilament has stable strength and low tissue reaction, assessed for strength, knotting and handling. Non-absorbable multifilament handles well and exhibits capillarity, assessed for strength, knotting and capillarity. Absorbable monofilament is assessed for degradation and strength retention. Absorbable multifilament handles well and is assessed for degradation, strength retention and capillarity. Needled sutures combine needle and thread and are assessed for needle performance and attachment strength. And barbed sutures avoid knotting and are assessed for barb holding. Capillarity deserves attention in multifilament sutures, since it can draw bacteria along the thread into deeper tissue.

Examining strength. Straight tensile strength covers the material's breaking force. Knot tensile strength covers breaking force once knotted, which is the more clinically relevant measure. The ratio between knotted and straight strength reflects the effect of knotting. Knotting method matters, since different methods give different results and a specified method should be used. Diameter corresponds to the size designation. And elongation covers extension at break. Knot strength is the key measure: sutures in the body are always knotted, and however high the straight strength, a large reduction on knotting leaves inadequate holding.

Examining knotting performance. Knot security covers whether knots slip. Number of throws covers how many some materials need to secure a knot. Knot volume affects the quantity of foreign material in tissue and how it feels. Handling covers smoothness and feel while tying. And memory covers whether the material retains shape, which affects handling. Knot slippage is a real clinical risk: some smooth monofilaments hold knots poorly and need more throws, and the product documentation should state the recommended knotting method and number of throws.

Examining degradation of absorbable materials. The strength retention profile covers strength against time in simulated body fluid and is the core data for absorbable sutures. Complete absorption time covers full degradation. Degradation products cover the substances generated and their effects. Factors affecting degradation rate include pH, temperature and tissue type. And matching to healing requires that the strength retention period covers the time tissue needs to heal. Give the strength retention profile at several time points rather than a single figure for strength at a given day, since the profile shows how strength declines.

Examining needles. Needles on needled sutures matter equally. Penetration force covers the force to pass through tissue, affecting handling and tissue trauma. Needle strength covers resistance to bending and fracture, since a broken needle left in the body has serious consequences. Point sharpness and geometry affect penetration and trauma. Body geometry covers curvature radius and cross-section. Needle-to-suture attachment strength covers the risk of the thread pulling free. And surface treatment affects smoothness of passage. Attachment strength should be verified, since separation interrupts the procedure and can cause difficulty during deep work.

Biocompatibility and tissue reaction. Contact nature involves prolonged tissue contact for non-absorbable materials or degradation in the body for absorbable ones. Items follow implantable product requirements. Tissue reaction covers the degree of inflammatory response. Degradation product effects apply to absorbable materials. And coating effects apply where coatings improve handling, since coatings also require evaluation. Coating evaluation is easily overlooked while coatings contact tissue directly and may shed.

Sterility and packaging. Sutures are sterile products. Sterilisation compatibility matters particularly for absorbable materials, since it may affect degradation characteristics. Packaging must maintain thread shape, permit aseptic presentation and prevent kinking. And shelf life covers the storage stability of absorbable materials. The effect of sterilisation on absorbable materials requires verification, since irradiation and similar methods may accelerate degradation and alter the strength retention profile.

How we handle it. For suture testing we treat knot strength as the priority measure and tie to the specified method, since knotting method noticeably affects results and results must be comparable. For absorbable materials we suggest strength retention profiles at several time points, measured in simulated body fluid at body temperature, since that data set directly underpins clinical suitability. For needled products we test needle-to-suture attachment strength and needle bending and fracture resistance, since a broken or detached needle has serious consequences.

Send us the product type and specifications and we will work through the items. Phone or WeChat: +86 132 4819 8029.