不同性别不同层次肋软骨的生物力学性能研究

Biomechanical properties of costal cartilage in different genders and layers

目的探讨不同性别、不同层次肋软骨在生物力学性能上的差异,为临床上使用肋软骨提供参考。方法根据入选标准从四川省人民医院整形外科住院部和门诊部收集2018年6月至2019年12月,需通过采取肋软骨进行耳廓再造,或需利用肋软骨进行支撑治疗的患者。将软骨支架雕刻后剩余的第7肋软骨中央层和边缘层制成不同规格的软骨块,分别进行拉伸强度试验、压缩试验(包括蠕变试验和应力松弛试验)。计数资料以例数进行描述,统计推断组间差异用Fisher精确检验;计量资料采用均值±标准差表示,组间比较用t检验分析,以P<0.05为差异有统计学意义。结果共收集28例患者,其中男性16例,年龄12~24岁,女性12例,年龄12~18岁。共制作方形软骨块112块、长方形软骨块56块。拉伸强度试验中,男性肋软骨中央层拉伸断裂率为87.5%(14/16),边缘层为0,两者比较差异有统计学意义(P<0.001);女性肋软骨中央层拉伸断裂率为83.3%(10/12),边缘层为0,两者比较差异有统计学意义(P<0.001)。蠕变试验中,男性肋软骨中央层与边缘层在0.5 min至2 min之间的蠕变量差异无统计学意义(t=-1.439、P=0.171),女性中央层与边缘层比较差异亦无统计学意义(t=-0.731、P=0.480)。应力松弛试验中,男性肋软骨中央层应力松弛量与边缘层比较,差异无统计学意义(t=-2.053、P=0.058);女性肋软骨中央层应力松弛量为(0.006±0.003)%,边缘层为(0.011±0.004)%,显著高于中央层,差异有统计学意义(t=-3.342、P=0.007)。结论少年及青年群体中男性和女性肋软骨中央层在抗拉伸强度上较边缘层差,且其中的钙化点明显减弱了肋软骨的抗拉伸能力,临床上应针对不同部位及用途,根据软骨的钙化情况选择合适的层次。

Objective The mechanical properties of costal cartilage of different genders and layers were tested,and the differences in mechanical properties of costal cartilage of different genders and layers were discussed.The theoretical basis was provided for the clinical use of costal cartilage of different layers in different situations,and the long-term effect after cartilage implantation could be predicted.Methods According to the inclusion criteria,from June 2018 to December 2019,patients who receive dauricle reconstruction with costal cartilage or supporting treatment with costal cartilage were collected from the Inpatient and Outpatient Department of Plastic Surgery of Sichuan Provincial People’s Hospital.The remaining central and marginal layers of the seventh costal cartilage were made into different sizes of cartilage blocks.The tensile strength test and compression test(including creep test and stress relaxation test)were carried out respectively.The counting data were described by the number of cases,and Fisher exact test was used to analyze the differences between groups;the measurement data were expressed by mean±standard deviation,and the comparison between groups was analyzed witht-test.Results A total of 28 patients,including 16 males,aged 12-24 years old and 12 females,aged 12-18 years old,were collected.In the tensile strength test,the tensile fracture rate of the central layer of costal cartilage in male was 87.5%(14/16)and that of marginal layer was 0,the difference was statistically significant(P<0.001).The tensile fracture rate of central layer of costal cartilage in female was 83.3%(10/12),and that of marginal layer was 0,the difference was statistically significant(P<0.001).In the creep test,there was no significant difference between the central layer and the marginal layer between 0.5 min and 2 min in men(t=-1.439,P=0.171),and there was no significant difference between the central layer and the marginal layer in women(t=-0.731,P=0.480).In the stress relaxation test,there was no significant difference between the central layer of costal cartilage and the marginal layer in male(t=-2.053,P=0.058);in female,the stress relaxation in the central layer of costal cartilage was(0.006±0.003)%,and that in the marginal layer was(0.011±0.004)%,which was significantly higher than that in the central layer(t=-3.342,P=0.007).Conclusions The central layer of the costal cartilage in young people is worse than the marginal layer in tensile strength,and the calcification obviously weakens the tensile strength of the costal cartilage.Clinically,considering the calcification of the cartilage,the appropriate layer should be selected according to different parts and uses.