Objective:To report the sampling study design and radiography protocol of a large-sample investigation on skeletal maturation of 3 to 18-year-old children in China.Methods:Multi-stage stratified random sampling was employed in this study. Two provinces, municipalities, or autonomous regions were randomly selected from each of the seven regions of China, including Northeast China, Northwest China, North China, Central China, East China, Southwest China, and South China. Then one rural and one urban investigation site were randomly selected from each province, municipality, or autonomous region. In total 28 sites were included. Among those sites, four residential districts were randomly selected from each urban site, and four townships from each rural site. For each residential district or township, 1-4 kindergartens, primary schools, and middle schools were chosen. Random cluster sampling was used to extract 3-<6-year-old children in kindergartens, and 6-18-year-old children in primary schools and middle schools. The investigation on skeletal maturation was sampled proportionate to the sampling of the whole study. The estimated simple size was 780 for each site, and 21 840 for all 28 sites in total. There were six groups of 3-<6-year-old children classified at 0.5-year intervals, and 12 groups of 6-18-year-old children classified at 1-year intervals. Posteroanterior position radiography of the left hand and wrist was achieved for all subjects.Results:The study was performed from August 26, 2019 to October 16, 2021. In total, 20 444 children received posteroanterior position radiography of the left hand and wrist, including 10 196 males and 10 248 females, 9 711 urban and 10 733 rural, respectively. The 3-<6-year-old group included 1 611 (male 819, female 792) subjects, and the 6 to 18-year-old group included 18 833 (male 9 377, female 9 456) subjects.Conclusion:This nationwide investigation on skeletal maturation of 3 to 18-year-old children in seven regions of China was successfully preformed. The results of this study can provide an important reference for establishing the current evaluation criteria of bone age in Chinese children and adolescents.

Objective:To evaluate the applicability of bone age (BA) assessment methods and to investigate the difference between BA and chronological age (CA) based on the data of children in rural areas of Beijing.Methods:A total of 412 healthy children (226 boys, 186 girls) with the age 8.6 (6.8, 10.3) years old were included in this study. The data of the prospective study were from a subgroup of the project "National Nutrition and Health Systematic Survey for 0-18 Years Old Children in China", which included children with age of 3-12 years old in Beijing rural areas. The non-dominant hand-wrist radiographs of all participants were obtained in April 2021. The Dr.Wise BA detection and analysis system was used to assess the BA according to the Tanner Whitehouse 3 (TW3) radius-ulna-short bone score (TW3-RUS), TW3 carpal bone score (TW3-Carpal), China-05 TW3-Chinese RUS (TW3-C RUS), China-05 TW3-Chinese carpal (TW3-C Carpal), and Greulich-Pyle (G-P) standards. The cases were stratified by the sex and different CA in the statistical analysis. The estimated BA obtained using different methods were compared with the CA using Wilcoxon signed ranks test.Results:The sex-stratified results showed that no significant difference was found between the estimated BA using G-P standards and CA in boys ( Z=-0.694, P=0.488), while all the other estimated BA results were statistically significantly higher than CA ( P<0.05). Stratified by both sex and CA, the estimated BA using G-P standards in 4-6 years old boy groups, as well as the estimated BA using TW3-Carpal and TW3-C Carpal standards in 11-12 years old girl groups were lower than CA, while in the other groups, the estimated BA were higher than CA. Conclusions:There were varying degrees of deviations in the BA estimations using TW3, China 05, and G-P methods for children in rural areas of Beijing. It is imperative to establish a new standard for the BA evaluation of the contemporary Chinese children.

Objective:To explore the accuracy of artificial intelligence (AI) system based on deep learning in evaluating bone age of children with abnormal growth and development.Methods:The positive X-ray films of the left wrist of children with abnormal growth and development who were treated at the Affiliated Hospital of Guizhou Medical University from January 2020 to December 2021 were collected retrospectively. A total of 717 children were collected, including 266 males and 451 females, aged 2-18 (11±3) years. Based on Tanner Whitehouse 3 (TW 3)-RUS (radius, ulna, short bone) and TW3-Carpal (carpal bone) method, bone age was measured by 3 senior radiologists, and the mean value was taken as reference standard. The bone ages were independently evaluated by the AI system (Dr.Wise bone age prediction software) and two junior radiologists (physicians 1 and 2). The accuracy within 0.5 year, the accuracy within 1 year, the mean absolute error (MAE) and the root mean square error (RMSE) between the evaluation results and the reference standard were analyzed. Paired sample t-test was used to compare MAE between AI system and junior physicians. Intraclass correlation coefficient (ICC) was used to evaluate the consistency between AI system, junior physician and reference standard. The Bland-Altman diagram was drawn and the 95% consistency limit was calculated between AI system and reference standard. Results:For TW3-RUS bone age, compared with the reference standard, the accuracy within 0.5 year of AI system, physician 1 and physician 2 was 75.3% (540/717), 62.1% (445/717) and 66.2% (475/717), respectively. The accuracy within 1 year was 96.9% (695/717), 86.3% (619/717) and 89.1% (639/717), respectively. MAE was 0.360, 0.565 and 0.496 years, and RMSE was 0.469, 0.634 and 0.572 years, respectively. For TW3-Carpal bone age, compared with the reference standard, the accuracy within 0.5 year of AI system, physician 1 and physician 2 was 80.9% (580/717), 65.1% (467/717) and 71.7% (514/717), respectively. The accuracy within 1 year was 96.0% (688/717), 87.3% (626/717) and 90.4% (648/717), respectively. MAE was 0.330, 0.527 and 0.455 years, and RMSE was 0.458, 0.612, 0.538 years, respectively. Based on TW3-RUS and TW3-Carpal bone age, the MAE of AI system were lower than those of physician 1 and physician 2, and the differences were statistically significant ( P all<0.001). The evaluation results of AI, physician 1 and physician 2 were in good agreement with the reference standard (ICC all>0.950). The Bland-Altman analysis showed that the 95% agreement limits of AI system for assessing TW3-RUS and TW3-Carpal bone age were -0.75-1.02 years and-0.86-0.91 years, respectively. Conclusion:The accuracy of AI system in evaluating the bone age of children with abnormal growth and development is close to that of senior doctors, better than that of junior doctors, and in good agreement with senior doctors.

CT 检查是骨科常用的检查之一,在各种骨科疾病的诊疗中具有重要作用.近年来 CT 机的扫描速度更快,探测器更宽,剂量更低,使得 CT 的临床应用更加普及.多数 CT 使用的球管产生的是混合能量的射线,当 X 线穿过被检组织时会被组织吸收而发生衰减,测量 CT 值可以反映组织的密度.

Objective:To analyze the clinical characteristics of hemangiolymphangiomas of hand and upper extremity.Methods:From January 2010 to October 2018, 12 patients with hemangiolymphangiomas of hand and upper extremity were treated. The epidemiological characteristics, clinical characteristics, diagnosis and treatment were summarized, and the results of 11 cases followed up were analyzed.Results:Hemangiolymphangioma is a congenital malformation of venous and lymphatic vessels. It is rare in hand and upper extremity. It is often found after birth. The dorsal part of the hand is susceptible, and the radial half is common. After operation, 11 cases obtained follow-up. The follow-up time was 6 to 60 months, with an average of 22 months. The results of operation were satisfactory and definite.Conclusion:Although hemangiolymphangioma is a benign disease, it is easy to affect the appearance and even function of hands or limbs because of its rapid growth. It is advisable to treat it as early as possible. The special attention should be paid to the closure of lymphatics and vascular stumps. If the tumor has a wide range, staging operation is recommended.

1 病例简介 病例1,女,3岁,主诉:左膝酸胀伴功能受限3个月.体格检查:左膝关节功能受限.实验室检查无异常.左膝关节正侧位片、CT及MRI示股骨远端骨骺及干骺端骨质破坏(图1A～E).行肿物切除术,病理结 果 为 卡 波 西 样 血 管 内 皮 瘤( Kaposiform hemangioendothlioma,KHE)(图1F).

患者,男,44岁,因"腰骶部疼痛3个月,加重伴疼痛1个月"入北京积水潭医院.患者4个月前出现腰骶部疼痛,平卧症状不明显,行走后疼痛加重.入院查体:腰骶部无肿胀畸形,无红肿压痛.辅助检查:2015年3月13日CT示骶1右侧见类圆形溶骨性骨质破坏,边界清晰,大小约 29 mm×26 mm×25 mm,其内密度不均,内见脂肪密度及条状软组织密度影,CT值为-70～10 Hu,增强扫描见不均匀条状强化,强化区软组织影CT为53 Hu (图1A～1C).2015年3月17日MRI示骶1右侧见骨质破坏,T1WI主要呈高低混杂信号,T2WI主要呈明显高信号,T2WI压脂可见病 灶部分区域信号减低,并见多发管状留空血管影,增强扫描见明显不均匀强化(图1D～1G).入院后行肿瘤刮出骨水泥填充术,术后病理示病灶脂肪组织呈分叶状,内见较多扩张的血管,符合血管脂肪瘤(图1H).

Objective To investigate the diagnostic discordance for osteoporosis using spine quantitative computed tomography (QCT) and dual-energy X-ray absorptiometry (DXA) in the elderly Chinese population.Methods Totally 614 subjects older than 60 years underwent both QCT scanning and spine,hip DXA.The diagnosis of osteoporosis by DXA was followed the standard of World Health Organization (WHO):T score ≤-2.5 SD as osteoporosis,-2.5--1.0 SD as osteopenia,≥-1.0SD as normal.The diagnosis of osteoporosis by QCT was followed the criterion recommended by the American College of Radiology:bone mineral density of lumbar vertebra ＜ 80 mg/cm3 as osteoporosis,＞ 120 mg/cm3 as normal,80 mg/cm3 ≤ bone mineral density ≤ 120 mg/cm3 as osteopenia.Minor discordance was defined as when the diagnostic difference between two methods was only one diagnostic class.Major discordance was present when one was osteoporotic and the other was normal.The diagnostic differences between DXA and QCT were compared.Results In 614 participants [mean age (76.3 ± 26.0) years],major discordance,minor discordance,and concordance of osteoporotic diagnosis by DXA and QCT were found in 5.9％,46.9％ and 47.2％,respectively.The detection rate of DXA (spine P-A projection,hip) on osteoporosis was lower than that of QCT (x2 =177.96,P＜0.01).Conclusion Bone mineral density measurements of lumbar vertebra by QCT play an important role on the diagnosis of osteoporosis in elderly Chinese population.

患者,女,42岁,1年前无意中发现右前臂远端掌侧出现一包块,不伴疼痛,未予处理.于2014年12月右前臂肿胀加重,对症处理后疼痛略有缓解.2015年5月再次出现右前臂疼痛,包块增大,并出现右腕关节屈伸活动轻度受限.X线示(见图1):右前臂软组织肿胀.电子计算机断层扫描(computed tomography,CT)示(见图2):右前臂中远端掌侧可见梭形软组织肿物,边界不清,临近桡骨可见少量骨膜反应;增强病灶中度、不均匀强化.MRI示(见图3):T1呈中等信号,T2WI呈中高混杂信号,临近桡骨可见少量骨膜反应;增强病灶明显不均匀强化.

Objective To investigate the imaging diagnosis and differential diagnosis features of hip soft tissue tumors.Methods The imaging materials of 13 cases of hip soft-tissue tumors confirmed by postoperative pathological findings were retrospectively analyzed.Nine had plain film X-ray examination done,twelve had a CT examination,all of the thirteen cases had an MRI examination done,and 3 underwent CT to reexamine the lung conditions after surgery.Results Only five of nine cases examined by plain film X-ray showed positive results,and all of the CT and MRI examination showed positive hip soft tissue tumors as well.The benign tumors were smooth and regular in shape,with a homogeneous density with uniform enhancement or without enhancement.The malignant tumors were irregular and lobular in shape,with heterogeneous density,peritumoral irnfiltration and obvious heterogeneous enhancement.Conclusion Imaging examination,especially MRI,is highly sensitive to soft tissue tumors,which is very helpful to increase the accuracy for the diagnosis and differentiation of hip soft tissue tumors.

患者男,27岁.3个月前无明显诱因感左髋部持续性疼痛,为持续性,与行走等运动无关,休息后难以缓解,初次就诊诊断为骨性关节炎,未予特殊治疗.后疼痛逐渐加重,以夜间痛为主,口服止痛药可稍缓解,可自触及左髋部及大腿内侧肿胀,并逐渐增大.X线平片表现:左股骨颈溶骨性骨质破坏,边缘可见硬化(图1).CT表现:左侧股骨头及股骨颈不规则片状骨质破坏区,其内点状高密度,有硬化边,局部皮质塌陷并破坏,邻近软组织肿胀,较周围肌肉组织密度稍低,边界不清.增强检查,股骨病变轻度强化,周围软组织块显著不均匀强化(图2).MRI表现:左侧股骨头及股骨颈髓腔内骨质破坏,呈长T1、长T2信号,前外侧骨皮质受侵,邻近可见不均匀稍短T1、稍长T2信号软组织,股骨近端髓腔内及股四头肌大范围水肿,呈长T2高信号.增强检查:股骨病变及周围软组织块呈不均匀强化,肿胀的股四肌头呈明显不均匀强化,邻近皮下软组织呈长T1、长T2水肿信号(图3).术前MRI检查考虑恶性占位性病变.

患者女,51岁,右膝关节疼痛行走不适4年,加重1年。4年前无明显诱因出现右膝关节不适、无力、行走障碍,对症治疗后症状缓解;近1年来症状加重,经中药及针灸治疗后症状无缓解,行走运动时疼痛加剧。体检:右下肢跛行,右小腿近端稍肿胀,局部皮温正常,无明显感觉障碍及压痛。X线平片表现:右胫骨近端骨质破坏,边界模糊不清,周围骨皮质不光整（图1）。CT表现:右胫骨近端溶骨性骨质破坏,边界不清,局部骨皮

Objective:To investigate the application value of MR mDIXON-quant technique in accurate quantification of liver fat content in type 2 diabetic patients with non-alcoholic fatty liver disease (NAFLD).Methods:98 subjects were studied in this research,including 33 males and 16 females in diabetic group,33 males and 16 females in control group (non-diabetic group).All subjects underwent liver MR mDIXON-quant imaging,and liver fat content was measured on MR workstation.The difference of detection rate of non-alcoholic fatty liver was compared between the two groups.Results:The median fat content of liver was 5.5％ (first quartile 3.8％,third quartile 11.0％) in diabetic group and 3.7％ (first quartile 2.5％,third quartile 5.7％) in control group.The total detection rate of fatty liver was 59.2％ in diabetic group,and 30.3％ in control group.In the male subjects,the detection rate of fatty liver in diabetic group (63.6％,21/33) was higher than that in control group (30.3 ％,10/33),and the difference was statistically significant.In female subjects,the detection rate of fatty liver in diabetic group (50％,8/16) was higher than that in control group (25％,4/16),and the difference was not statistically significant.Conclusion:Quantification of liver fat content by MR mDIXON-quant technique was convenient and accurate,and it may provide important reference for assessment of screening,diagnosis and therapeutic effect of type 2 diabetic patients with NAFLD.

病史：患者，女，60岁，北京积水潭医院门诊患者，主诉双侧髋部疼痛1年余，伴髋部偶有弹响，既往体健，无明显外伤史。查体：双侧髋关节后伸同时内收、外旋时疼痛加剧。实验室检查：血常规、C反应蛋白未见异常。

病史：患者，女，21岁，22个月前出现左髋关节无诱因疼痛，程度可耐受，不伴发热、夜间痛、盗汗，未服用药物。查体见左下肢轻度跛行，左髋关节皮肤不红，未见静脉曲张，皮温不高、未触及肿胀、包块，局部深压痛，未及血管杂音，关节被动及主动活动可，四肢感觉运动可，肢端血运活动可，病理征未引出。

患者,女,20岁。右膝部疼痛1年,发现局部包块1个月。1年前无明显诱因出现右膝部外侧疼痛,钝痛呈间歇性,局部无明显肿胀,无发热。行走后疼痛加重,休息可稍好转,未行诊治。1月前发现局部包块,外院拍片发现右腓骨近端骨病变。查体:右小腿近端外侧稍肿胀,皮肤颜色正

目的 评价定量CT(QCT)骨密度测量在诊断老年男性骨质疏松症中的应用价值.方法 收集我院同时接受腰椎DXA、髋关节DXA和腰椎QCT检查、年龄＞60岁的男性受检者314例.比较DXA和QCT对骨质疏松症检出率的差异.结果 DXA(腰椎正位、髋关节)对老年男性骨质疏松的检出率(35/314,11.15％)低于腰椎QCT对老年男性骨质疏松的检出率(141/314,44.90％;x2=88.70,P＜0.05).结论 腰椎QCT BMD测量对中国老年男性人群骨质疏松症的早期诊断具有重要作用.

目的:探讨实验性骺板损伤修复过程中的显微CT表现及病理变化.方法:取4～5周龄Wistar大鼠50只,选择右侧胫骨制作骺板损伤动物模型,左侧作为对照.分别于造模后1、3、7、11和21 d各选取10只大鼠处死,取双侧胫骨行显微CT扫描,观察损伤骺板的影像特征,并通过组织学切片HE染色,观察骺板内组织细胞的动态改变.结果:①对照侧骺板显微CT及组织形态表现.造模后1d,显微CT图像显示骨骺与干骺端高密度带间波浪形带状低密度区,边缘清晰;造模后7d,骺板轻度变窄;11d后逐渐明显变窄,中间部位较边缘显著;21 d时骺板区密度增高,明显变窄.造模后1d,骺板HE染色切片示骺板4层结构清晰可见,软骨细胞呈柱状规律排列;7 d后幼稚软骨细胞逐渐减少,增殖层细胞柱逐渐稀疏,肥大层宽度减小,细胞膨大、退化,骺板逐渐变窄,其中以造模后21 d表现最明显.②观察侧骺板显微CT及组织形态表现.造模后1d,显微CT可见干骺端骨折;造模后3～7d,骺板宽度先增加,然后趋于正常;11d时骺板宽度减小伴新生骨质形成,干骺端下见迂曲透亮影;21 d时骺板宽度明显变窄,骨桥形成.HE染色显示损伤早期骺板细胞正常结构消失,肥大层结构紊乱,组织出血、水肿;造模后7d时静止层细胞聚集,并大量出现在损伤区,同时软骨细胞增殖活跃;11 d时损伤区出现大量静止层细胞,软骨细胞增殖活跃,成簇的软骨细胞团伸入干骺端;21 d时损伤区见成熟小梁骨横贯干骺端至骨骺.结论:显微CT空间分辨率高,可动态反映骺板损伤的修复过程,是研究实验性小动物骺板损伤理想的影像学检查方法.

Objective To analyze the clinical and imaging features of pulmonary metastasis of giant cell tumor of bone for clinical diagnosis and treatment.Methods Five patients with histologically proven pulmonary metastasis from giant cell tumor of bone were reviewed,the imaging features and the progression of the pulmonary metastasis were evaluated.Results The first operation of primary tumor was curettages and then local recurrence was seen in all 5 cases.The interval to metastasis ranged from 5 to 26 months.Pulmonary metastasis was diagnosed by chest radiographs in 4 cases and CT in all 5 cases.The imaging findings included solitary solid nodule (n =1),multiple solid nodules and mass (n =5),multiple groundglass nodules (n =1) and complex form (n =2).The dynamic follow-up CT findings showed spontaneous regress nodules (n =1),metastasis occurring again 19 months after surgery of solitary nodule (n =1),some solid nodules unchangable for a long time in 3 patients with multiple nodules.Conclusions The dynamic follow-up CT findings of pulmonary metastasis of giant cell tumor of bone are specific.The regular follow-up could play an essential role in early detection and prognosis of pulmonary metastasis within 2 years after primary tumor diagnosed.

Objective To explore the feasibility and application of determining the center of the inferior portion of the glenoid on a standard anteroposterior view of the normal glenoid. Methods Seventy shoulders of 35 mature adults were measured in this study. A 64-slice CT 3D reconstruction was performed for each glenoid. A standard anteroposterior view and the scale of glenoid were made at a 3D workstation by one radiologist, and then transferred to software AutoCAD as 2D images. The 2D images were analyzed with AutoCAD respectively by 3 radiologists. The line was drawn between the most anterior and the most inferior points of the glenoid bony rim. On the same image, another line was drawn between the most posterior and the most inferior points of the glenoid bony rim. Two perpendicular bisectors of the 2 lines were drawn. The cross point of the 2 perpendicular bisectors was regarded as the circle center of the inferior part of the glenoid. The distances from the circle center to the anteroinferior and the posteroinferoir rims of the glenoid and the most posterior point were measured. Measurements were expressed as the mean ± standard deviation. Several related samples Friedman rank sum test was used to compare the measurements (the distance from the circle center to the most posterior point) by the 3 radiologists. Paired t tests were used to compare the differences between the left and right glenoids. Results The mean distance from the circle center to the most posterior point was ( 14. 1 ± 1.6) mm, the anteroinferior rim was ( 14. 0 ± 1.7) mm, and the posteroinferoir rim was ( 14. 1 ±1.6) mm. No significant differences were found ( P>0. 05) between measurements by the 3 radiologists. No significant differences were found ( P>0. 05) between the measurements of the both-side glenoids. Conclusions The method of determining the center of the inferior portion of the glenoid based on the most anterior,posterior and inferior points of the glenoid on a standard 3D anteroinferior view of the normal glenoid is easy,practical and highly repeatable. The radius of the left glenoid is comparable to the radius of the right side in normal shoulders. This method can be used to quantify a glenoid bone defect precisely.