Finite element analysis (FEA) is broadly used in biomechanics.Being widely used in clinical studies on cervical spine injury,cervical degeneration and stimulating a variety of cervical spine surgeries,cervical finite element model is becoming more and more accurate in recent years.This paper aims to review the development of cervical finite element model,to introduce the application progress of the modeling and analysis in cervical spine injury,cervical disc arthroplasty,cervical interbody fusion,cervical degeneration and cervical instability,and to prospect the foreground of cervical finite element model in future.

Objective To analyze the relationship between pillow height and cervical intervertebral disc stress in lateral decubitus position of the human body using three-dimensional finite element method,and to provide the basis for appropriate pillow selection.Methods A cervical spine CT scan was performed on a normal male volunteer.The medical 3D image reconstruction software (Mimics),reverse engineering software (Geomagic Studio) and finite element software (MSC.Patran) were collectively used to establish three-dimensional finite element models of the whole cervical spine under three lateral decubitus conditions,includes pillow height of 10 cm (cervical spine leftward flexion),17 cm (cervical spine neutral),and 25 cm (cervical spine rightward flexion).Moreover,the finite element analysis and calculation of the three models were conducted.Results The Von-Mises stress,maximal principal stress and maximum shear stress of the model in cervical spine neutral (pillow height=17 cm) were all significantly lower than those of the cervical spine lateral model.Conclusions When the cervical coronal plane is in neutral position,the cervical discs can achieve the best stress distribution state.In lateral decubitus position of the human body,a appropriate pillow height should make the cervical vertebrae in neutral position.

Objective To investigate the predictive role of the intraoperative amylase ( IOA ) from pancreatic stump for postoperative pancreatic fistula. Methods The clinical data of 26 patients who received distal pancreatectomy ( DP) and central pancreatectomy ( CP) in the Shanghai Ruijin Hospital from June 2017 to July 2018 were retrospectively analyzed. IOA and peri-operative potential clinical factors associated with pancreatic fistula were analyzed. Receiver operating characteristics ( ROC) curve was drawn to evaluate the diagnostic efficacy of IOA from pancreatic stump in predicting postoperative pancreatic fistula, and the sensitivity and specificity were calculated. Results Of 26 patients, 19 patients underwent DP and 7 patients underwent CP. 9 patients (34.6％,9/26)had class A pancreatic fistula (biochemical leak) and 11 patients (42. 3％,11/26) had class B pancreatic fistula after surgery, and no class C pancreatic fistula occurred. Univariate analysis showed that IOA from pancreatic stump in clinically relevant pancreatic fistula group was higher than that in clinically irrelevant pancreatic fistula group(7971. 82 ± 4387. 98 vs 1589. 20 ± 1405. 00, P=0. 001). Area under the curve ( AUC) of IOA in predicting the development of clinically relevant pancreatic fistula after surgery was 0. 921 and 95％ confidential interval was 0. 807-1. 000. The optimal cut-off value was 3622 U/L , and the sensitivity and specificity were 90. 9％ and 86. 7％. Conclusions IOA from pancreatic stump could serve as a clinical indicator for predicting the occurrence of postoperative pancreatic fistula.