【摘要】 目的 本研究拟基于肘关节正侧位 X 线及 CT 三维重建等影像学资料，采用定量化的评估方法，分析肱骨远端低位通髁骨折的形态特点。方法 回顾性纳入 2013 年 1 月至 2019 年 11 月，就诊于我院创伤骨科的肱骨远端低位通髁骨折患者，排除不具备医学数字成像和通信格式的术前肘关节正侧位 X 线及肘关节 CT 资料的患者。将 X 线及 CT 数据导入 Mimics 20.0，通过该软件测量并计算 X 线正位片中内侧 / 外侧骨折线高度，内 / 外上髁高度，骨折线内侧 / 外侧髁上高度，骨折线-关节面倾角及骨折线-内外上髁倾角 (均取锐角，夹角开口向尺侧则为正值，开口向桡侧则为负值)；测量 X 线侧位片中的侧位骨折倾角 (肱骨前缘线与近端骨折线的背侧夹角)；测量模拟骨折复位后 CT 三维重建下骨折线分割鹰嘴窝的上下部分占比。对于符合正态分布的计量资料采用 ■ 表示，对于不符合正态分布的数据，用中位数 (第 25 百分位，第 75 百分位) 描述。结果 本研究共纳入 51 例，年龄 74 (56，79) 岁，范围 14～94 岁，男女比例 15∶36，右肱骨伤 30 例，左肱骨伤 21 例。骨折线内侧髁上高度[5.26 (3.79，6.97) mm]显著大于骨折线外侧髁上高度[1.05 (0.24，2.28) mm](P < 0.001)，骨折线-关节面倾角[11.21 (6.40，15.14) °]及骨折线-内外上髁倾角[5.60 (3.00，7.75) °]均显著 > 0° (P < 0.001)，侧位骨折倾角[123.98 (119.45，129.11) °]显著 > 90° (P < 0.001)。骨折线分割鹰嘴窝的上部分占比[64.3 (57.50，68.01) %]大于下部分占比[35.63 (31.99，42.50) %](P < 0.001)。上述指标的性别差异均无统计学意义。上述测量指标的观察者内信度均 > 0.75。结论 肱骨远端低位通髁骨折具有独特的形态特征，骨折线呈现“内高外低”和“前高后低”分布，绝大多数表现为“类屈曲型”损伤，且骨折线贯穿鹰嘴窝的中间偏下部分。不同性别间骨折线的分布特征无显著差异。更多还原

【Abstract】 Objective To quantitatively evaluate the morphological features of low transcondylar fractures of the distal humerus by radiographic measurements based on X-ray and 3D-CT scan.Methods We retrospectively included patients with low transcondylar fractures of the distal humerus who were treated in our hospital from January 2013 to November 2019.And we excluded the patients without preoperative X-ray and CT scan of elbow joints in the format of digital imaging and communications in medicine (DICOM).Mimics 20.0 was used to measure radiographic parameters including the height of medial and lateral fracture line,the height of medial and lateral epicondyle,supracondylar height of medial and lateral fracture line,the angle between fracture line and articular surface as well as the angle between the fracture line and epicondylar level (acute angles were measured;positive numbers were recorded if the angular openings were towards the ulnar side;negative numbers were recorded if towards the radial side),fracture inclination angle in lateral view (dorsal angle between the anterior humeral line and fracture line of the proximal fracture fragment),and the proportion of the upper and lower parts of the olecranon fossa divided by the fracture line after simulated fracture reduction.The measurement data conforming to the normal distribution were expressed by ■.For data that did not conform to a normal distribution,it was described using the median(the 25th percentile,the 75th percentile).Results A total of 51 patients were enrolled,aged 74 (56,79) years(range:14-94 years),with a male to female ratio of 15:36.The affected side included 30 cases in right side and 21 cases in left side.The supracondylar height of the medial fracture line[5.26 (3.79,6.97) mm]was significantly higher than the lateral side[1.05 (0.24,2.28) mm](P < 0.001).The angle between the fracture line and articular surface[11.21 (6.40,15.14) °]as well as the angle between the fracture line and epicondylar level[5.60 (3.00,7.75) °]were significantly larger than 0 degree (P < 0.001).The inclination angle in lateral view[123.98 (119.45,129.11) °]was significantly larger than 90 degrees (P < 0.001).The proportion of the upper part of the olecranon fossa divided by the fracture line[64.3 (57.50,68.01) %]was significantly larger than that of the lower part[35.63 (31.99,42.50) %](P < 0.001).There was no significant difference between male and female patients in the parameters above.Intraclass correlation coefficient of intra-rater reliability of all the measurementsabove were more than 0.75.Conclusions Low transcondylar fracture of the distal humerus has unique morphological features.The fracture line is higher on the medial side but lower on the lateral side,and it is higher on the volar side but lower on the dorsal side.The majority of these fractures manifests as “flexion-type-like” injury and the fracture line runs through the lower middle part of the olecranon fossa.There is no significant difference between male and female patients regarding to morphological features.更多还原