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Objective To compare the biomechanical effects of contiguous three-level cervical Hybrid surgery[anterior cervical discectomy and fusion (ACDF) + cervical disc arthroplasty ( CDA)] and three-level ACDF. Methods The finite element model of C1-T1 cervical-thoracic spine was developed based on CT data. Three models were simulated by the implantation of Prestige LP and Zero-P prostheses, including two Hybrid models (AFA, Prestige LP implanted at C3-4 and C5-6 segments and Zero-P implanted at C4-5 segment; FAF, Zero-P implanted at C3-4 and C5-6 segments and Prestige LP implanted at C4-5 segment) and three-level ACDF model(FFF). The changes in range of motion (ROM) of adjacent levels during flexion, extension, lateral bending and axial rotation, the overall ROM, as well as the intradiscal pressure ( IDP) and facet contact force ( FCF) of adjacent levels were compared. Results The ROM in adjacent levels and the overall ROM of the AFA modelwere closer to the intact model, and the maximum increases in the ROM of the adjacent levels for the FAF and FFF models were 15. 0% and 23. 4% , respectively. For AFA, FAF and FFF models, the maximum increases in the maximum IDP of adjacent levels were 19. 0% , 66. 7% , 147. 6% , and the maximum increases in FCF were 17. 4% , 55. 7% , 80. 1% , respectively. Conclusions This study provides biomechanical basis for three-level cervical Hybrid surgery in treating patients with the contiguous three-level cervical degenerative disc disease.
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Objective To explore the relationship between urinary iodine level and breast cancer,we compare urinary iodine excretion levels in patients with breast cancer,benign breast disease,other female malignant tumors and control subjects in Xiangya Hospital of Central South University.Methods From December 2018 to January 2019,64 patients with newly diagnosed breast cancer in Xiangya Hospital of Central South University were selected as case group,benign breast disease group (n =49),other female malignant tumor group (n =39) and health examination group (n =50) as control group.Urinary iodine was determined by colorimetry.According to the urinary iodine level the patients divided into three groups:iodine excess (＞300 μg/L),medium iodine (100-300 μg/L) and iodine deficiency (＜ 100 μg/L).The relationship between urinary iodine and clinicopathology of breast cancer was analyzed.Results The level of urinary iodine in benign breast nodule group 319.13 (163.98) μg/L ＞ breast cancer group 273.96 (151.30) μg/L ＞ female other malignant tumor group 212.95 (161.71) μg/L ＞ normal control group 199.15 (194.45) μg/L,with significantly differance (H =9.936,P =0.019).Urinary iodine level in the normal control group was significantly lower than that in the benign breast disease group (P =0.013).The patients were further divided into three groups according to the urinary iodine level:iodine excess,iodine medium and iodine deficiency,the number of urine iodine ＜ 100 μg/L in the normal control group was significantly higher than that in the breast cancer group (P =0.021).The level of urinary iodine was negatively correlated with the size of the primary focus of breast cancer (Z =-2.307,P =0.021).The effect of urinary iodine was analyzed by multiple linear regression method.The size of primary focus was included in the regression equation (R2 =0.136,P=0.007),but had nothing to do with lymph node metastasis and the expression status of estrogen receptor (ER),androgen receptor (AR),progesterone receptor (PR) and human epidermal growth factor receptor-2 (HER-2).Conclusions There is a negative linear correlation between urinary iodine level and the size of primary focus of breast cancer,but it has nothing to do with lymph node metastasis and the expression of ER,AR,PR and HER-2.