PDF(Pubmed)
Abstract：
OBJECTIVE: Ni-Ti memory alloys are unusual materials for hard-tissue replacement because of their unique superelasticity, good biocompatibility, high strength, low specific gravity, low magnetism, wear resistance, corrosion resistance and fatigue resistance. The current study aims to evaluate its mechanical properties and provide biomechanical basis for the clinical application of the prosthesis.
METHODS: Ten adult metacarpophalangeal joint specimens were randomly divided into a prosthesis group (n = 5, underwent metacarpophalangeal joint prosthesis) and a control group (n = 5, underwent sham operation). Firstly, the axial compression strength was tested with BOSE material testing machine to evaluate its biomechanical strength. Secondly, these specimens were tested for strain changes using BOSE material testing machine and GOM non-contact optical strain measurement system to evaluate the stress changes. Thirdly, fatigue test was performed between groups. Lastly, the mechanical wear of the metacarpophalangeal joint prosthesis was tested with ETK5510 material testing machine to study its mechanical properties.
RESULTS: Axial compression stiffness in the prosthesis group was greater than that in the control group in terms of 30 ° and 60 ° flexion positions (P < 0.05). There was no statistically significant difference between two groups with regards to axial compression stiffness and stress change test (P > 0.05). In the fatigue wear test, the mean mass loss in the prosthesis group\'s prosthesis was 17.2 mg and 17.619 mm3, respectively. The mean volume wear rate was 0.12%. There was no statistically significant difference in the maximum pull-out force of the metacarpal, phalangeal, and polymer polyethylene pads between the prosthesis group and the control group specimens.
CONCLUSIONS: Ni-Ti memory alloy metacarpophalangeal joint prosthesis conforms to the biomechanical characteristics of metacarpophalangeal joints without implants, and the fatigue strength can fully meet the needs of metacarpophalangeal joint activities after joint replacement.
METHODS: Ten adult metacarpophalangeal joint specimens were randomly divided into a prosthesis group (n = 5, underwent metacarpophalangeal joint prosthesis) and a control group (n = 5, underwent sham operation). Firstly, the axial compression strength was tested with BOSE material testing machine to evaluate its biomechanical strength. Secondly, these specimens were tested for strain changes using BOSE material testing machine and GOM non-contact optical strain measurement system to evaluate the stress changes. Thirdly, fatigue test was performed between groups. Lastly, the mechanical wear of the metacarpophalangeal joint prosthesis was tested with ETK5510 material testing machine to study its mechanical properties.
RESULTS: Axial compression stiffness in the prosthesis group was greater than that in the control group in terms of 30 ° and 60 ° flexion positions (P < 0.05). There was no statistically significant difference between two groups with regards to axial compression stiffness and stress change test (P > 0.05). In the fatigue wear test, the mean mass loss in the prosthesis group\'s prosthesis was 17.2 mg and 17.619 mm3, respectively. The mean volume wear rate was 0.12%. There was no statistically significant difference in the maximum pull-out force of the metacarpal, phalangeal, and polymer polyethylene pads between the prosthesis group and the control group specimens.
CONCLUSIONS: Ni-Ti memory alloy metacarpophalangeal joint prosthesis conforms to the biomechanical characteristics of metacarpophalangeal joints without implants, and the fatigue strength can fully meet the needs of metacarpophalangeal joint activities after joint replacement.
摘要：
目的：Ni-Ti记忆合金由于其独特的超弹性，是用于硬组织替代的不寻常材料，良好的生物相容性,高强度,低比重,低磁性，耐磨性，耐腐蚀性和抗疲劳性。本研究旨在评价其力学性能,为该假体的临床应用提供生物力学依据。
方法：将10例成人掌指关节标本随机分为假体组（n=5，接受掌指关节假体）和对照组（n=5，接受假手术）。首先,用BOSE材料试验机测试轴向压缩强度，以评估其生物力学强度。其次,使用BOSE材料试验机和GOM非接触式光学应变测量系统测试了这些试样的应变变化，以评估应力变化。第三，组间进行疲劳试验.最后,采用ETK5510材料试验机对掌指关节假体的机械磨损进行测试，研究其力学性能。
结果：在30°和60°屈曲位置，假体组的轴向压缩刚度大于对照组（P<0.05）。两组在轴向压缩刚度和应力变化测试方面差异无统计学意义（P>0.05）。在疲劳磨损试验中,假体组假体的平均质量损失分别为17.2mg和17.619mm3.平均体积磨损率为0.12%。掌骨最大拔出力差异无统计学意义,指骨,假体组和对照组标本之间的聚合物聚乙烯垫。
结论：Ni-Ti记忆合金掌指关节假体符合无植入物掌指关节的生物力学特征，且疲劳强度能充分满足关节置换后掌指关节活动的需要。
方法：将10例成人掌指关节标本随机分为假体组（n=5，接受掌指关节假体）和对照组（n=5，接受假手术）。首先,用BOSE材料试验机测试轴向压缩强度，以评估其生物力学强度。其次,使用BOSE材料试验机和GOM非接触式光学应变测量系统测试了这些试样的应变变化，以评估应力变化。第三，组间进行疲劳试验.最后,采用ETK5510材料试验机对掌指关节假体的机械磨损进行测试，研究其力学性能。
结果：在30°和60°屈曲位置，假体组的轴向压缩刚度大于对照组（P<0.05）。两组在轴向压缩刚度和应力变化测试方面差异无统计学意义（P>0.05）。在疲劳磨损试验中,假体组假体的平均质量损失分别为17.2mg和17.619mm3.平均体积磨损率为0.12%。掌骨最大拔出力差异无统计学意义,指骨,假体组和对照组标本之间的聚合物聚乙烯垫。
结论：Ni-Ti记忆合金掌指关节假体符合无植入物掌指关节的生物力学特征，且疲劳强度能充分满足关节置换后掌指关节活动的需要。
