Application of three-dimensional digital reconstruction and printing technology in the clinical teaching of complex orthopedics / 中华医学教育探索杂志

Objective To explore the effect of 3d digital reconstruction and printing technology on the teaching of complex orthopedics. Methods A total of 90 interns in the Second Affiliated Hospital of Inner Mongolia Medical University from September 2016 to September 2017 were selected as research subjects. According to the different teaching methods, they were divided into control group (n=45) and experimental group (n=45). The former received traditional teaching;the latter used three-dimensional digital reconstruction and printing technology to print out complex fracture models of patients, digitally reproduced fracture classification, developed scientific surgical plans through fracture models, and simulated surgical fixation methods. Examination was divided into clinical skills and written exam according to exam outline requirements; Self-cognitive ability score included professional interest, fracture understanding, etc. The satisfaction of the medical students in the experimental group was determined using self-made questionnaires. t test was used to compare data between groups. Results Experimental groups' scores for surgical skills (84.36 ±0.28) and theoretical knowledge (87.55 ±0.44) were higher than the control group, and the differences were statistically significant (P<0.05). The professional interest of the experimantal group was higher than that of the control group, and the difference was statistically significant (P<0.05). The students' classroom atmosphere was significantly better compared with the control group, and the difference was statistically significant (P<0.05). Conclusion Using 3 d digital reconstruction and printing technology to establish modes in complex orthopedics teaching process can effectively improve interns' surgical skills and theoretical knowledge, and promote student satisfaction.

Finite element analysis of distal femoral locking plate and minimally invasive internal fixation system in different motion states / 中国组织工程研究

BACKGROUND:Traditional distal femoral fixation plate screw breakage is relatively common. Designing good anatomical and attached fixation system is the key for clinical application. OBJECTIVE:To perform finite element analysis in two states of motion of the minimal y invasive distal femoral fixation system, compare stress distribution of different parts in the same fixed way, different fixed methods and the same fixed parts of different motion states. METHODS:Imaging data of a 34-year-old male patient weighing 68 kg with 33-C1 type fracture of distal femur were selected. CT data were input into Mimics 16.0 for reconstruction. PRO-E software was used to establish minimal y invasive internal fixation system with distal femoral locking plate. Data were introduced into reconstructed models of distal femur fracture in Mimics for grid division. Data were introduced into Ansys products 11.0 to construct finite element model, fix the surface of distal femur, and loaded 340 N on greater trochanter of femur. Stress distribution of each plate, screw hole and screw tail was analyzed in each group. Stress at the same region was compared in flexion and extension movement states. RESULTS AND CONCLUSION:(1) Finite element models of anatomic locking plate for distal femur fracture fixation were successful y established, total y 43 536 units, 41 256 nodes. (2) With the steel segment gradual y down (S1-S5), the stress gradual y increased. A1-A5 with the increase in the number of screws, the stress gradual y increased, but A6 suddenly decreased. (3) According to the cloud atlas of stress, these were wel distributed except A1. From distal end to extremity of screw, the stress of screws increased. Among corresponding segments, significant differences in stress around the nail holes and steel segment stress were detected. Moreover, the steel stress was greater than the stress of corresponding segment of screw hole. (4) Results suggest that using anatomical locking plate and minimal y invasive internal fixation system for distal femur fracture in a variety of fixed modes and moving conditions, the stress of each part is less than the yield strength of the titanium al oy screw, so the fixed system wil not produce instantaneous deformation or fracture.

Using in-situ replantation of dead bone to treat infected nonunion of femur / 中国矫形外科杂志

[Objective]To study the techqiue and method of using in-situ replantation of dead bone to treat infected nonunion of femur. [Method] Debridement and removal of dead bone were carried out in 2 patients who had a chunk of dead bone and multiple sinus without involucrum formation.Sterilized sequester was replanted in-situ,tibia traction was performed and continual Kawashima's irrigation was applied with sensitive antibiotic after surgery.[Result]The time of bone healing in 1 case was ten months.The patient was followed up for 42 months,there was no recurrence of osteomyelitis.The time of bone healing in another case was about 12 months,he was followed up for 30 months,there was also no recurrence in this patient.[Conclusion]Traumatic osteomyelitis complicated with a massive sequester and nonunion could be cured by process which included debridement,in-situ replantation of sterilized death bone,continual washing as well as comprehesive treatment.It could achive the two primary purposes,inflammation cure and bone healing.Among these methods,improved Kawashima's irrigation is the most important method for inflammation cure and bone union.

Analysis of surgical treatment of huge primary liver cancer:report of 86 cases / 中国现代普通外科进展

Objective:To explore the possibility and methods of surgical treatment(ST) for huge primary liver cancer(HPLC).Methods:The clinical data of 86 HPLC were analyzed retrospectively and the main challenges as well as their counter measures during ST are concluded.Results:Among the 86 cases,there were 10 cases which complicated with portal vein(PV),and 5 cases with IVC thrombus respectively;there were 76 cases with HBV cirrhosis,2 HCV cirrhosis,there were 60 and 26 cases of primary and secondary hepatectomy in which included regular right(9 cases),left hemihepatectomy(8 cases)and combined hepatectomy(69 cases).Six cases received PV embolism before surgery.There were 10 and 5 cases of cancer thrombus extraction from PV and IVC respectively.In this group,81 patients were cured,and the perioperative mortality was 5.8%(5/86).The postoperative one—year survival rate for the patients was 77.9%.Conclusions:ST for HPLC is safe and acceptable.Full of preoperative assessment,careful intraoperative exploration,and surgical skill played a key roles.