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BACKGROUND:Avascular necrosis of the femoral head is a refractory orthopedic disease that seriously affects the normal life of patients.Hip preservation is recommended for young patients due to the limited prosthesis longevity and revision.Accurate prediction of the mechanical properties of the necrotic area in the early stage and then intervention is the key to hip preservation. OBJECTIVE:To establish a dynamic contact mechanics finite element model of necrotic femoral head based on human hip CT data and predict effects of both necrotic volume magnitude and its position on biomechanics of the necrotic region under walking movement. METHODS:CT data of a volunteer were collected and then geometry model of the hip was rebuilt.Finite element model of the necrotic femoral head was established using the Abaqus software.Nine different necrotic femoral models were constructed by combined both three different necrotic volume magnitudes(small,medium and big volume)and three different necrotic positions(coincided with,medium deviated with and kept away from the line of the force).The Von Mises of the necrotic region for all models were predicted under both 3 000 N static load and dynamical loads of one whole ISO walking gait cycle.The collapse risk for all models was evaluated based on collapse criterion. RESULTS AND CONCLUSION:(1)More approaching of the necrotic region to the line of force and bigger collapse volume made the maximum Von Mises increasing.This also enlarged the collapse risk of the necrotic region.(2)For different load types,walking movement increased the maximum Von Mises of the necrotic region than that of the value under static load under the same necrotic volume and location.(3)In conclusion,dynamic load would result in increasing of the maximum Von Mises of the necrotic region comparing to static load during exercise.Therefore,the risk of local collapse will increase due to greater Von Mises.However,the overall collapse risk is lower than that of static load due to the dynamic change of bearing area.This factor should be carefully considered by surgeons when they evaluate the mechanical performance of the necrotic femoral head.
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Objective:To investigate the risk factors and clinical significance of lymph nodes metastasis between sternocleidomastoid and sternohyoid muscle lymph node (LNSS) metastasis in thyroid cancer patients, so as to guide the reasonable dissection of LNSS region and lateral cervical lymph node in patients with papillary thyroid carcinoma (PTC) .Methods:We selected 111 PTC patients with lateral cervical lymph node metastasis who underwent radical thyroidectomy and lateral cervical lymph node dissection from Nov. 2018 to Dec. 2021 in China-Japan Union Hospital of jilin university. All patients were treated with low collar arc incision. Radical thyroidectomy and lateral cervical lymph node dissection were performed according to the guidelines, and lymph nodes in each district were grouped for pathological examination. According to whether LNSS metastasis occurred, they were divided into two groups: LNSS positive group (LNSS metastasis occurred) and LNSS negative group (LNSS metastasis did not happen). We collected the basic information of all 111 PTC patients with lateral lymph node metastasis (LLNM), preoperative color Doppler ultrasound examination and paraffin-embedded pathology and other related clinical case data. Then we described the clinicopathological features of cervical lymph node metastasis. Independent sample t test and Mann-Whitney U test were used for continuous variables, and Fisher exact test was used for data analysis for classified variables. Correlation analysis adopted binary logistics regression model, and analyzed the regularity and risk factors of LNSS metastasis. Results:In this study, the detection rate of LNSS was 64.9% (72/111), the overall LNSS metastasis rate was 7.2% (8/111), and the number of lymph node metastasis was 0-5. Univariate analysis showed that the location of LNSS metastasis was related with the cancer focus ( P<0.001), the preoperative serum thyroglobulin (Tg) level ( P=0.002), the number of lymph node metastasis in lateral cervical level Ⅳ ( P=0.001), the longest diameter of the cancer focus ( P=0.003) and the longest diameter of metastatic lymph nodes ( P=0.001) However, age, sex, whether there is lymph node metastasis in the central region (central lymph node metastasis ,CLNM), and whether there is multifocal cancer were not related to LNSS metastasis ( P≥0.05). Further multivariate analysis and work curve analysis of subjects showed that the tumor located in the lower pole ( P=0.014) and the number of lymph node metastasis in level Ⅳ more than 3 ( P=0.027) were independent risk factors for LNSS metastasis. It was found that the risk of LNSS metastasis increased when the cancer focus was located at the lower pole relative to the upper pole or middle part of the cancer focus ( OR=74.508, 95% CI: 2.373-2339.544). The number of lymph node metastasis in level Ⅳ had a positive effect on LNSS metastasis. The more lymph node metastasis in level Ⅳ, the higher the risk of LNSS metastasis ( OR=1.556; 95% CI=1.051-2.303) . Conclusions:In PTC patients with LLNM, the LNSS metastasis rate was 7.2%, and the advantages of LNSS cleaning outweigh the disadvantages. When the cancer focus is located at the lower pole and the number of lymph node metastasis in region Ⅳ is more than 3, it is necessary to pay attention to the dissection of this group of lymph nodes.
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Objective To discuss the effective factors and metastasis rules of cervical lymph node of papillary thyroid microcarcinoma,aimed to provide references for indications and range of lymph node dissection.Methods Reviewed the clinical information and pathological material of primary treatment of 1 180 cases of papillary thyroid microcarcinoma patients in China-Japan Union Hospital of Jilin University from June 2008 to December 2011 by retrospective analysis,futher summared cervical lymph node metastasis rules and effective factors.Results The lymph node metastasis rate of 1 180 patients with papillary thyroid microcarcinoma was 29.6％,which of these of the central and lateral region were 26.4％ and 15.2％.Central region lymph nodes metastasis rates in male and female were respectively 44.9％,21.8％ (P ＜ 0.05),and were 39.8％,9.0％ in lateral region (P ＜ 0,01).Lymph node metastasis rates of patients whose age ≤45years old and ＞45 years old were 30.3％,17.9％ (P ＜0.05).The lymph mode metastasis rate which diameter of tumour(D) ≤0.5 cm or 0.5 cm ＜ D ≤ 1 cm in central region were 20.2％,33.2％ (P ＜ 0.05).The lymph node metastasis rate of single and more nidi respectively were 15.7％,45.0％ in central region.The lymph node metastasis rate of tumors invasion or not were 44.4％ and 14.2％ in central region (P ＜0.05).The metastasis rates were 45.5％ and 4.3％ in the lateral region when the lymph node infringe or not in central region.Conclusions Lymph node metastasis happens relatively more common in papillary thyroid microcarcinoma patients with the factors such as male,young age,multiple nidi,long diameter of tumor and invasion of tumor envelope.So when doctors establish the indications and range of lymph node dissection,it's need to pay attention to the high risk factors seriously which effect lymph node metastasis of papillary thyroid carcinoma,and establish the lymph node dissection strategy individually.
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ObjectiveTo investigate the mechanism and prevention of invisible injury of recurrent laryngeal nerve (RLN) system in thyroid surgery, with the application of intraoperative neuromonitoring ( IONM ) system. MethodsThe type of invisible RLN injury and its protection with the application of IONM system were analyzed. ResultsThe causes of invisible RLN injury mainly included stretching of Berry ligament or the tumor,contusion, thermal injury, cutting of silk and suction injury. RLN invisible injury was recoverable through neurotrophic and symptomatic treatment. No permanent vocal cord paralysis occurred. ConclusionsWith the application of IONM system, some invisible type of RLN injuries can be found. The risk of RLN injury can be reduced if the surgical techniques are improved with the development of study on mechanism of IONM system.
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Objective To analyze prevention and management of lymphatic fistula after cervical lymph node dissection in thyroid carcinoma.Methods Clinical data of 9 cases of lymphatic fistula following neck dissection were analyzed retrospectively from Jan.2004 to Apr.2009.Results Of the 9 cases,4 cases had chylous fistula(3 were on the leftside and 1 was on the rightside),1 case had chylotborax,1 case had pleural effusion lymph,and 3 cases showed light yellow lymph.AII patients were cured finally by conservative methods.Conclusions Most lymphatic fistula can be cured by non-surgical treatment.Surgeons need to be familiar with the anatomic structure of neck lymphatic vessels.
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Objective To approach the guide of ultrasound-guided minimally invasive biopsy technique in diagnosis and treatment of thyroid diseases. Methods One hundred and seventeen cases (a total of 131 nodules, nodules 0. 5-1.5 cm in diameter, with an average diameter of approximately 0. 8 cm) with thyroid nodules , under Ultrasound-guided minimally invasive biopsy techniques from October 2008 to July 2009 were analyzed. Result One hundred and seventeen cases of patients with biopsy derived satisfaction were not ap-parent discomfort and complications after biopsy. Across 59 cases of surgical treatment in patients with biop-sy, and preoperative biopsy and postoperative pathologic is not fully consistent in only two cases, 58 patients without surgical treatment, who is combined with symptoms, palpation, serum thyroxine and color Doppler ultrasound and other laboratory examinations, and regularly review treated with symptomatic treatment, the symptoms, and color Doppler ultrasound imaging were much better under the treatment. 8 cases of patients in 117 cases of minimally invasive biopsy have cervical lymph node biopsy at the same time, biopsy patholo-gy and postoperative results are consistent with postoperative pathologic (7 cases of metastatic carcinoma, 1 case of reactive hyperplasia), accuracy was 100%. Conclusion Uhrasound-guided minimally invasive bi-opsy technique have important guiding for diagnosis and treatment of thyroid diseases, consistent with the high rate of clinical, especially for the preoperative diagnosis of small nodules, to avoid unnecessary over-treatment, can also reduce the misdiagnosis of thyroid cancer. While this technology is simple, safe and ac-curate, which have clinical value in the thyroid surgery.
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Objective To find new way to reduce non-recurrent laryngeal nerve (NRLN) injuries by applying intraoperative neuromonitoring(IONM) to identify NRLN in thyroidectomy. Methods Records of 279 patients who underwent complex thyroidectomy by applying IONM to identify and monitor RLN from Mar. 2009 to Jan. 2010 were veviewed. We proposed the skills to identify and monitor NRLN and predict RLN varition through exploring vagus nerve and RLN before RLN dissection. Results 6 cases NRLN located on the right side were all accurately identified by IONM, thus no injury of NRLN occurred during thyroid operations. Conclusions NRLN is difficult to be predicted preoperatively and identified by naked eyes. The application of IONM to predict, identify and monitor NRLN could remarkably reduce the possibility of NRLN injury.