关键词: 缝合锚钉缝线, 超高分子量聚乙烯, 断裂强力, 两参数Weibull模型, 改进Weibull模型, 强度预测

Abstract: Suture anchors play a pivotal role in securely affixing soft tissue to the skeletal framework, having emerged as indispensable tools in the realm of orthopedic surgery. The genesis of suture anchors, comprised initially of metallic screws and sutures, traces back over three decades. In the pursuit of augmenting the tensile strength of these suture anchors, a plethora of variants have been conceived, encompassing metallic suture anchors, biodegradable suture anchors, bio-stable suture anchors, bio-composite suture anchors, and all-suture anchors. The quintessential suture anchor necessitates the provision of substantial mechanical stability to ensure the resolute fixation of soft tissue upon osseous substrates. Within the realm of suture anchors, it is noteworthy that improvements in the anchoring component have mitigated suture rupture as a primary cause of surgical failure in orthopedics. Thus, augmenting suture tensile strength represents the crux of the contemporary challenge. This investigation delves into the fabrication of high-strength suture anchor sutures and scrutinizes their mechanical properties. Leveraging a braiding methodology, we have manufactured high-tensile suture anchor sutures, further prognosticating the rupture strength of suture anchor sutures via both two-parameter Weibull model and modified Weibull model, thereby mitigating risks associated with the utilization of suture anchors.
In this experimental endeavor, 8.3 tex UHMWPE fibers were adopted as the primary raw material,  and a braiding technique was employed to engender single-layer braided sutures as well as axially-reinforced double-layer braided sutures. To scrutinize their mechanical properties, we selected varying intervals of 8, 16, 24, 32, 40, and 48 mm to test the tensile strength of individual fibers, opted for 50 and 200 mm intervals for assessing the tensile strength of 8.3 tex filaments, and relied upon a 200 mm interval for gauging the tensile strength of single-layer braided sutures and axially-reinforced double-layer braided sutures. Concurrently, the diameter of fibers and the angular displacement between fibers within the sutures were subjected to meticulous measurement. Subsequently, both the two-parameter Weibull model and the modified Weibull model were employed to characterize the tensile strength of individual fibers, 8.3 tex filament, and single-layer braided sutures.
The findings unveiled that the fracture strength of single-layer braided sutures stood at 299.8 N, whereas axially-reinforced double-layer braided sutures exhibited an impressive fracture strength soaring to 393.0 N. Regrettably, when utilizing the two-parameter Weibull model to prognosticate the rupture strength of 8.3 tex filament and single-layer braided sutures, substantial disparities from actual values were noted, with all predictions falling outside the 95% confidence interval of the observed values and an accuracy rate of less than 5%. Conversely, the forecasts derived from the modified Weibull model consistently fell within the 95% confidence interval of the actual values, attesting to their superior accuracy.
This study's manufactured high-tensile suture anchor sutures evince superior tensile strength when juxtaposed with analogous medical sutures. The axially-reinforced double-layer braided sutures, in particular, attain a formidable rupture strength of 393.0 N. Whether it pertains to the prediction of the tensile strength of 8.3 tex filament or single-layer braided sutures, the modified Weibull model's prognostications surpass the accuracy of those rendered by the two-parameter Weibull model. Furthermore, by employing the modified Weibull model, it becomes possible to predict the tensile strength from individual fibers to filaments and subsequently to yarns. This achievement establishes a solid theoretical foundation for future research in medical suture structural design and mechanical performance analysis.

Key words: suture anchor sutures, UHMWPE, fracture strength, two-parameter Weibull model, modified Weibull model, strength prediction