不同年龄段健康国人肱骨头区域骨皮质区域性分布差异分析

Age-related changes in cortical bone material distribution in the humeral head region in healthy Chinese people using computed tomography

目的 探讨不同年龄段健康人群肱骨头区的骨皮质区域性分布差异.方法 本研究共纳入健康志愿者51人,男27人,女24人;年龄20～88岁,平均48.69岁.所有健康志愿者行肩部CT扫描,按照年龄分为3组：A组（20～39岁）17人;B组（40～59岁）18人;C组（≥60岁）16人.应用骨皮质测量软件Stradwin 5.2读取CT原始影像数据,生成骨皮质的彩色分布图.垂直于肱骨头关节面,将肱骨头高度四等分后建立相互平行的3个横截面;在横断面1、2、3,测量分析肱骨头区前壁、外侧壁和后壁的骨皮质厚度、骨皮质密度和皮质下骨小梁密度.结果 在A组,骨皮质厚度和密度在肱骨头区前壁、外侧壁、后壁差异均有统计学意义（P值均〈0.01）;在B、C组,骨皮质厚度和密度在肱骨头区前壁、外侧壁、后壁相似,差异均无统计学意义（P值均〉0.05）.后壁的骨皮质厚度和密度在A、B、C组的横截面1、2中均较低.在C组的横截面3,外侧壁的骨皮质厚度和密度值最低.A、B、C组在横断面1、2、3中各个测量点的皮质下骨小梁密度差异均无统计学意义（P值均〉0.05）.结论 在各个年龄段,肱骨头区的骨皮质区域性分布差异程度不同,40岁以后差异程度有所减弱.肱骨头区的外侧壁或者后壁,是骨皮质的薄弱区域.

Objective To evaluate the cortical bone material distribution of the humeral head region in different-age groups.Methods Fifty one healthy volunteers who underwent computed tomography scanning on shoulder were included in this study, and were divided into 3 groups according to the age： group A （17 individuals, 20-39 years old）, group B （18 individuals, 40-59 years old） and group C （16 individuals, ≥60 years old）. Image analysis was performed on CT imaging data of these volunteers from Stradwin 5.2 software, a novel technique called cortical bone mapping, and the thickness maps for each proximal humerus were generated. Then three cross-sections （1, 2, 3 section） parallel to each other were established in the humeral head region. In the 1-3 sections, the cortical thickness （CTh）, cortical mass surface density （CMSD）, and endocortical trabecular bone mineral density （ECTD） in the anterior, lateral and posterior wall of the humeral head area were measured and analyzed.Results With regard to CTh and CMSD, there were significant differences among the anterior, lateral and posterior wall in the 3 cross-sections of group A （all P values〈0.01）, while no difference was found in group B and C （all P values〉0.05）. The CTh and CMSD of the posterior wall were the lowest in the cross-sections 1-2 among the 3 groups, and both parameters of the lateral wall were lowest in the cross-section 3 in the group C. There was no difference in ECTD data among different cortical locations in the three groups（all P values〉0.05）.Conclusions There was significant regional variation of cortical bone material distribution in proximal humerus, and the degree of the regional variation decreased after the age of 40. Cortical bone material in posterior or lateral wall is structurally vulnerable.