Fleischer J, Schleyer A, Nassutt R, Grittner U, Ojodu I, Hopp S J
Department of trauma and orthopedics, Marien hospital, Am Hirschberg, 66606 St. Wendel, Germany.
Biomechanic laboratory, university of Lübeck, Lübeck, Germany.
Orthop Traumatol Surg Res. 2017 Apr;103(2):165-169. doi: 10.1016/j.otsr.2016.12.001. Epub 2017 Jan 16.
Tuberosity repair in shoulder fracture prosthesis implantation still remains a challenge often leading to poor functional outcomes, despite a variety of materials and suggested suture patterns. We aimed to evaluate, which forces currently used suture and cerclage materials withstand and to assess whether they are useful with regard to stability of reconstruction of tuberosities and which failure modes they display.
Using sheep infraspinatus tendons with attached tuberosities three different suture materials (suture 1: Ethibond size 2; suture 2: Orthocord size 2; suture 3: Fiberwire size 5) and a 0.8mm titanium cerclage wire were investigated. For each suture material as well as the cerclage wire 6 tests were carried out. A material testing machine was used to perform cyclic loading tests (20mm/min, F=50N, F=100N, respectively after 50 cycles: F+50N until failure). Outcome measures and thus comparison criteria were the maximum holding force, number of cycles reached, total elongation of the system (tendon and suture) and qualitative appraisal and documentation of the mechanism of failure.
Overall average maximum forces between the fixation materials differed significantly (P=0.003), especially suture 3 (braided polyethylene coating, non-resorbable polyfile UHMW core) displayed superior results in comparison to the cerclage wire (P=0.016). Although, primary elongation of the cerclage technique was significantly lower compared to the suture materials (P=0.002). All tests showed a high initial lengthening and caused incision-like defects in the bone or tendon and led to failure and huge displacement of the tuberosities.
Currently used suture and cerclage materials have a limited usefulness for refixation of tuberosities due to an increased risk of obstruction for bony consolidation.
Basic science, Biomechanics.
尽管有多种材料和建议的缝合方式，但在肩部骨折假体植入中，结节修复仍然是一项挑战，常常导致功能预后不佳。我们旨在评估目前使用的缝合线和环扎材料能承受哪些力，并评估它们在结节重建稳定性方面是否有用以及它们会表现出哪些失效模式。
使用带有附着结节的绵羊冈下肌腱，研究了三种不同的缝合材料（缝合线1：2号Ethibond；缝合线2：2号Orthocord；缝合线3：5号Fiberwire）和一根0.8毫米的钛环扎线。对每种缝合材料以及环扎线都进行了6次测试。使用材料试验机进行循环加载测试（20毫米/分钟，分别施加F = 50N、F = 100N，50个循环后：F + 50N直至失效）。结果测量指标以及比较标准为最大保持力、达到的循环次数、系统（肌腱和缝合线）的总伸长量以及对失效机制的定性评估和记录。
固定材料之间的总体平均最大力存在显著差异（P = 0.003），特别是缝合线3（编织聚乙烯涂层，不可吸收聚烯烃超高分子量芯）与环扎线相比表现出更好的结果（P = 0.016）。尽管如此，环扎技术的初始伸长量与缝合材料相比显著更低（P = 0.002）。所有测试均显示出较高的初始伸长，并在骨或肌腱中导致类似切口的缺陷，导致失效以及结节的巨大移位。
由于骨愈合受阻风险增加，目前使用的缝合线和环扎材料在结节重新固定方面的作用有限。
基础科学，生物力学。
