Imaging Features And Differential Diagnosis Of Pelvic Bone Destruction In Children

The function of the pelvis is to transmit the weight of the body and participate in the formation of the hip joint.Pelvic bone destruction is the loss of bone tissue caused by local bone replaced by pathological tissue.It is often the result of direct or indirect enhancement of osteoclast activity caused by tumor and inflammation.Cortical bone or cancellous bone can be involved.Because of the complex structure of pelvis and its surrounding tissues,abundant blood supply and collateral circulation,the tumors here are often characterized by the diversity of histopathological types.Children with pelvic bone destruction are rare in clinic.Because of the complicated anatomical relationship of the pelvis and the overlap of the pelvic organs,it is difficult to detect the changes of bone destruction in the early stage.The combination of clinical features,imaging findings and pathology is the basis for diagnosis of bone destruction.The imaging manifestations of pelvic bone destruction in children are different.It is difficult to make a correct diagnosis by clinical and imaging features in most cases before operation.Misdiagnosis and misdiagnosis often occur.Most of the pelvic bone destruction in children is located in the iliac bone,involving the sciatic,pubic and sacral bones.Combined with the results of histopathology,the distribution of pelvic bone destruction in children and its imaging manifestations were analyzed,so as to improve the level of differential diagnosis of pelvic bone destruction in children by clinicians.Pelvic anatomy is complex and adjacent to many important organs,blood vessels and nerves.The resection and reconstruction of pelvic tumors has always been a difficult point in the field of bone tumor surgery.3D(three-dimensional)printing technology is a type of rapid prototyping technology.Bone tumor solid model printed with different materials,personalized surgical guide plate and personalized simulated metal implant can achieve complete customization,and play a better auxiliary role in bone tumor treatment.The position and boundary of pelvic tumors can be observed from different angles with the help of 3D printed digital three-dimensional models.Orthopedics doctors can visually observe the extent of pelvic tumors invasion before operation,thus determining the boundaries of the tumors,grasping the complex anatomical structures around the lesions and planning the operation process in advance,and performing complex operations.Preoperative planning,surgical simulation and surgical design should be avoided as far as possible.At present,there are few reports about the application of 3D printing technology in the surgical treatment of pelvic tumors in children.Based on the digital three-dimensional reconstruction technology,with the help of 3D printed anatomical model,to explore the value of its application in children's pelvic tumor surgery planning.Part ? Imaging features and differential diagnosis of iliac bone destruction in childrenObjective:To investigate the distribution and imaging manifestations of iliac bone destruction in children,so as to improve the diagnostic level of pelvic bone destruction in children by clinicians.Methods:The clinical data of 32 children with iliac bone destruction confirmed by surgically and pathological in two children,s hospitals from August 2008 to August 2018 were retrospectively analyzed.Combined with postoperative pathological diagnosis,the clinical features and imaging findings were analyzed.Results:In 32 cases,22 cases were males,10 cases were females,the average age of treatment was 5.2±2.2 years(11 months to 13 years).Hip pain as the chief complaint were enrolled in 14 cases,limping in 8 cases,hip pain with low fever in 6 cases,unintentional X-ray findings in 4 cases and so on.Location of lesion:11 cases of left iliac bone,19 cases of right iliac bone,2 cases of bilateral iliac bone.The duration of the disease ranged from 2 days to 1 months,with an average of 12.6±4.3 days,Routine DR films of anterior and posterior position of pelvis and full-length DR films of lower limbs were taken in 32 cases,plain spiral CT scan and three-dimensional reconstruction were performed in 28 cases,sagittal,axial and coronal MRI scans were performed in 18 cases.The main imaging manifestations were osteolytic bone destruction(21 cases),mixed bone destruction(8 cases),Inflated bone destruction(3 cases),clear lesion boundary(19 cases),blurred boundary(13 cases).10 cases were accompanied by soft tissue mass or swelling of different sizes,and periosteal reaction was seen in 4 cases.Histopathological diagnosis included 14 cases of eosinophilic granulorua of bone,9 cases of iliac metastasis of neuroblastoma,4 cases of osteomyelitis,2 cases of Ewing's sarcoma,1 case of bone cyst,1 cases of fibrous dysplasia of bone and 1 case of non-Hawking's lymphoma.Conclusion:There are various types of iliac bone destruction in children,most of the bony destruction is located in the iliac wing.Bone eosinophilic granuloma and neuroblastoma are the most common iliac tumor in childhood.The most common clinical symptoms were hip pain and lower limb lame.Imaging manifestations have certain characteristics in bone destruction of iliac in children,mainly osteolytic destruction,but the specificity of imaging manifestations is not high,histopathology must be considered for making a definite diagnosis.Part ? Imaging features and differential diagnosis of pubic,sciatic and sacral bone destruction in childrenObjective:To investigate the distribution and imaging manifestations of destruction in children,so as to improve the diagnostic level of pelvic bone destruction in children by clinicians.Methods:The clinical data of 8 children with pubic,sciatic and sacral bone destruction confirmed by surgically and pathological in two children's hospitals from August 2008 to August 2018 were retrospectively analyzed.Combined with postoperative pathological diagnosis,the clinical features and imaging findings were analyzed.Results:In 8 cases,6 cases were males,2 cases were females,the average age of treatment was 9.4±3.2 years(3 to 13 years).Hip pain with low fever as the chief complaint were enrolled in 3 cases,limping in 2 cases,hip pain in 2 cases,hip mass in 1 case and so on.Location of lesion:4 cases of ischium(3 case of left ischium,1 case of right ischium),2 cases of pubis(1 case of left pubis,1 case of right pubis),1 case of sacrum,1 case of iliac and sacrum involved.Routine DR films of anterior and posterior position of pelvis and full-length DR films of lower limbs,plain spiral CT scan and three-dimensional reconstruction and sagittal,axial and coronal MRI scans were performed in 8 cases.The main imaging manifestations were osteolytic bone destruction(6 cases),mixed bone destruction(2 cases),clear lesion boundary(2 cases),blurred boundary(6 cases).2 cases were accompanied by soft tissue mass or swelling of different sizes,and periosteal reaction was seen in 2 cases.Histopathological diagnosis included 3 cases of eosinophilic granuloma of bone,1 cases of Ewing's sarcoma,2 cases of tuberculosis,1 case of chronic osteomyelitis,1 case of peripheral primitive neuroectodermal tumor.Conclusion:Bone destruction of pubic,ischial and sacral bones in children is of various types.The most common clinical manifestations are hip pain with low fever and limb lameness.The imaging manifestations were mainly osteolytic destruction,but the specificity of imaging manifestations was not high.The final diagnosis needed pathological examination.Part ? Application of 3D printing technology in surgical planning of pediatric pelvic tumorsObjective:To explore the application value of 3D printing technology in the surgical planning of pediatric pelvic tumors.Methods:From August 2016 to August 2018,6 children with pelvic tumors were treated in the Department of Orthopedics,Children's Hospital of Nanjing Medical University.There were 4 males and 2 female,ranging in age from 11 months to 13 years,with an average age of 6.8 years,4 cases on the right side and 2 cases on the left side.According to Enneking's and Dunham's classification of pelvic tumors,the pelvic range was involved in 3 cases of type ?,1 case of type ? and 2 cases of type IV Pathological diagnosis was confirmed by biopsy or lesion biopsy before operation.There were 1 case of pelvic Ewing's sarcoma,1 case of peripheral primitive neuroectodermal tumor,1 case of iliac chondroma and 3 cases of eosinophilic granuloma of iliac bone.Before operation,32 rows of CT were used to scan the pelvis continuously,and Mimics and Geomagic Design Direct software were used according to CT data.The reconstructed STL file data was imported into a 3D printer.The 1:1 pelvic physical model was printed out by resin and plaster materials.The pelvic anatomy,preoperative evaluation and preoperative simulation were analyzed.Combined with the 3D reconstruction data,the reconstructed STL file data was accurately printed under the guidance of 3D pelvic model.Precise lesion removal is guided by the 3D print pelvic model.Results:All the 6 cases were successfully reconstructed and printed in 3D.The anatomy of pelvis and lesions,the adjacent relationship between tumor and pelvic vascular structure,and the volume of lesions were clearly displayed.All the 6 cases were resected accurately.The actual operation procedure was in accordance with the preoperative operation plan(6/6).There was no perioperative death and no serious complications.Conclusion:The 3D printing technique can clearly display the complicated anatomical relationship of pelvic tumors in children,help to plan the reasonable operation method before operation,and can accurately resect the lesions.