Threshold screw insertion torque for carbon fibre-reinforced polyetheretherketone and titanium (Ti-6Al-4V) locking plate constructs

IF 1.4 3区医学 Q4 ENGINEERING, BIOMEDICAL

Clinical Biomechanics Pub Date : 2026-04-01 Epub Date: 2026-01-22 DOI:10.1016/j.clinbiomech.2026.106769

Ramzi Nasr , Elise Pegg , Fedra Zaribaf , James Fletcher

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引用次数: 0

Abstract

Background

Locking plate constructs are integral to modern fracture fixation, particularly in osteoporotic bone. Carbon-fibre reinforced polyetheretherketone (CFR-PEEK) plates offer a stiffness profile closer to cortical bone than titanium, potentially improving the mechanical environment for healing. However, the optimal insertion torque for locking screws in CFR-PEEK plates is unclear. This study investigated the influence of insertion torque on construct performance in CFR-PEEK plates compared to titanium alloy (Ti-6Al-4V) plates.

Methods

Locking screws (3.5 mm, Ti-6Al-4V) were inserted into Ti-6Al-4V and CFR-PEEK plates at six torque levels (0.5–3.0 Nm). Construct strength was assessed via axial push-out and cantilever bending tests. Video analysis was used to correlate insertion torque with screw rotation. Additional testing was performed on two-screw CFR-PEEK constructs at three torque levels (0.5, 1.5, 2.5 Nm).

Findings

Insertion torque was linearly related to screw rotation within the tested range (0.5–3.0 Nm). In CFR-PEEK single screw constructs, higher torque (≥2 Nm) improved push-out strength (p < 0.05), while 1.5 Nm yielded the highest cantilever strength (p < 0.05). Ti-6Al-4V constructs showed a similar trend. In two-screw CFR-PEEK constructs, no significant differences were found in performance across torques for either push-out or cantilever testing (p > 0.5).

Interpretation

Beyond an initial threshold (∼0.5 Nm), increased insertion torque did not consistently enhance construct performance. These findings indicate that moderate torques (∼1.5 Nm) optimise performance while reducing the risk of implant damage, support the mechanical reliability of CFR-PEEK plates.

查看原文本刊更多论文

碳纤维增强聚醚醚酮和钛（Ti-6Al-4V）锁定板结构的阈值螺钉插入扭矩。

背景：锁定钢板结构在现代骨折固定中是不可或缺的，特别是在骨质疏松的骨骼中。碳纤维增强聚醚醚酮（CFR-PEEK）板提供比钛更接近皮质骨的刚度轮廓，潜在地改善愈合的机械环境。然而，锁定螺钉在CFR-PEEK板中的最佳插入扭矩尚不清楚。本研究比较了插入扭矩对CFR-PEEK板与钛合金（Ti-6Al-4V）板结构性能的影响。方法：将锁定螺钉（3.5 mm, Ti-6Al-4V）以6个扭矩水平（0.5 ~ 3.0 Nm）插入Ti-6Al-4V和CFR-PEEK板中。通过轴向推出和悬臂弯曲试验评估结构强度。使用视频分析将插入力矩与螺杆旋转相关联。在三个扭矩水平（0.5,1.5,2.5 Nm）下对双螺钉CFR-PEEK结构进行了额外的测试。结果：在测试范围内（0.5-3.0 Nm），插入扭矩与螺钉旋转呈线性相关。在CFR-PEEK单螺钉结构中，更高的扭矩（≥2 Nm）提高了推出强度（p 0.5）。解释：超过初始阈值（~ 0.5 Nm）后，插入扭矩的增加并不能持续提高构建体的性能。这些发现表明，适度的扭矩（~ 1.5 Nm）可以优化性能，同时降低植入物损伤的风险，支持CFR-PEEK板的机械可靠性。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Clinical Biomechanics 医学-工程：生物医学

CiteScore

3.30

自引率

5.60%

发文量

189

审稿时长

12.3 weeks

期刊介绍： Clinical Biomechanics is an international multidisciplinary journal of biomechanics with a focus on medical and clinical applications of new knowledge in the field. The science of biomechanics helps explain the causes of cell, tissue, organ and body system disorders, and supports clinicians in the diagnosis, prognosis and evaluation of treatment methods and technologies. Clinical Biomechanics aims to strengthen the links between laboratory and clinic by publishing cutting-edge biomechanics research which helps to explain the causes of injury and disease, and which provides evidence contributing to improved clinical management. A rigorous peer review system is employed and every attempt is made to process and publish top-quality papers promptly. Clinical Biomechanics explores all facets of body system, organ, tissue and cell biomechanics, with an emphasis on medical and clinical applications of the basic science aspects. The role of basic science is therefore recognized in a medical or clinical context. The readership of the journal closely reflects its multi-disciplinary contents, being a balance of scientists, engineers and clinicians. The contents are in the form of research papers, brief reports, review papers and correspondence, whilst special interest issues and supplements are published from time to time. Disciplines covered include biomechanics and mechanobiology at all scales, bioengineering and use of tissue engineering and biomaterials for clinical applications, biophysics, as well as biomechanical aspects of medical robotics, ergonomics, physical and occupational therapeutics and rehabilitation.