儿童枕骨髁及枕骨大孔数字化测量的临床意义

Clinical significance of digital measurement of occipital condyle and foramen magnum in children

背景:由于儿童年龄较小,枕骨髁和枕骨大孔尚未发育完全,容易发生枕颈交界区的各种疾病与创伤,严重时需手术治疗。但目前缺乏对儿童枕骨髁和枕骨大孔发育的解剖学参数。目的:利用三维重建技术对枕骨髁和枕骨大孔形态学结构进行相关测量,为枕颈交界区病变以及相关外科手术和法医鉴定提供重要的解剖学参数。方法:收集行螺旋CT扫描涉及颅底的原始儿童及青少年影像资料389例,其中男247例,女142例,年龄1-18岁。按照年龄分为1-3岁组、4-6岁组、7-9岁组、10-12岁组、13-15岁组和16-18岁组。利用Mimics 16.0软件三维重建颅底,测量枕骨大孔长度和宽度,并且利用公式计算出枕骨大孔面积和指数,测量枕骨髁长度、宽度、高度,枕骨髁长轴与矢状轴的夹角(O-S角),枕骨大孔前、后缘中点连线与枕骨髁后缘和枕骨大孔交点连线的夹角(F-O角),枕骨大孔前、后缘连线中点与舌下神经管后壁中点连线的夹角(F-H角)。对各指标间进行性别、侧别和年龄差异分析。结果与结论:①枕骨大孔测量除枕骨大孔指数不存在性别间的显著性差异(P>0.05)外,枕骨大孔最大长度和最大宽度、枕骨大孔面积均存在性别间差异(P<0.05);②枕骨髁的O-S角、F-O角和F-H角在性别间无显著性差异(P>0.05),枕骨髁长、枕骨髁高、枕骨髁宽在性别间差异(P<0.05);③枕骨髁长在侧别间无显著性差异(P>0.05),枕骨髁高、枕骨髁宽、O-S角、F-O角和F-H角在侧别间差异均有显著性意义(P<0.05);④枕骨大孔最大长度和最大宽度、枕骨大孔面积、枕骨髁长、枕骨髁高和枕骨髁宽随着年龄的增长呈波浪状递增的趋势;而O-S角、F-O角和F-H角随着年龄的增长呈波浪状递减趋势;枕骨大孔指数则无明显变化;⑤提示儿童枕骨大孔和枕骨髁的形态学指标在性别和侧别间存在差异,这些差异可为临床外科手术入路选择及法医检测提供重要的参考意义。

BACKGROUND:Due to the young age of children,the occipital condyle and foramen magnum are not fully developed,and they are prone to various diseases and injuries in the occipitocervical junction,which requires surgical treatment in severe cases.However,anatomical parameters for the development of the occipital condyle and foramen magnum in children are lacking.OBJECTIVE:To measure the morphological structure of the occipital condyle and foramen magnum by three-dimensional reconstruction technique,and to provide important anatomical parameters for occipitocervical junction lesions,related surgical procedures and forensic identification.METHODS:Imaging data of 389 cases of primitive children and adolescents involved in skull base undergoing spiral CT scanning(247 males and 142 females)aged 1-18 years were collected and divided into 1-3-year-old group,4-6-year-old group,7-9-year-old group,10-12-year-old group,13-15-year-old group,and 16-18-year-old group according to their age.Mimics 16.0 software was used to reconstruct the skull base and measure the length and width of the foramen magnum.A formula was used to calculate the area and index of the foramen magnum.We measured the length,width and height of the occipital condyle,the angle between the long axis and the sagittal axis of the occipital condyle(O-S angle),the included angle between the midpoint of the front and back edges of the foramen magnum and the connection between the back edge of occipital condyle and the intersection point of the foramen magnum(F-O angle),and the included angle between the midpoint of the front and back edges of the foramen magnum and the midpoint of the back wall of the sublingual neural tube(F-H angle).Gender,side and age differences were analyzed among the indicators.RESULTS AND CONCLUSION:(1)In foramen magnum measurement,there was no significant difference between sexes in the index of the foramen magnum(P>0.05),but there were significant differences in length,width and area of the foramen magnum(P<0.05).(2)The O-S angle,F-O angle and F-H angle of the occipitral condyle were not significantly different between genders(P>0.05),but length,width and height of the occipital condyle were significantly different between genders(P<0.05).(3)There were no significant differences in the length of the occipital condyle among different groups(P>0.05),but there were significant differences in the width and height of the occipital condyle,O-S angle,F-O angle and F-H angle among different groups(P<0.05).(4)Length,width and area of the foramen magnum,length,width and height of the occipital condyle showed a wavy increasing trend with the increase of age,while O-S,F-O and F-H angles showed a wavy decreasing trend with the increase of age,while the index of the foramen magnum showed no significant change.(5)In conclusion,there are gender and lateral differences in the morphological indexes of the foramen magnum and the occipital condyle in children.These differences can provide an important reference for clinical surgical approach selection and forensic examination.