Meta-analysis Of Internal Fixation For Proximal Humeral Fractures And Quantitative Imaging Evaluation

Objective:To systematically evaluate the functional outcome and complications of intramedullary nails and plates in proximal humeral fractures and investigate the degree of concordance between computed tomography(CT)values and X ray for some quantitative metrics in patients with proximal humeral fractures.Methods:Four databases were searched for all randomized controlled trials of intramedullary nails and plate treatments for proximal humeral fractures.Two examiners independently extracted data from the included studies and Reviewer Manager 5.3 was used for the data analysis.Then a retrospective study of patients with an X-ray and CT-confirmed diagnosis of proximal humeral fracture was performed.The radiographic parameters examined include the neck shaft angle(NSA),medial calcar(MC)displacement and metaphyseal extension(ME).As for the reliability of two measurement methods,intraclass correlation coefficient(ICC)was used to assess.In addition,correlation was analyzed using the Pearson or Spearman correlation tests and data differences were studied using paired sample t test or nonparametric test.Agreement assessments of surgery indication and fracture severity were evaluated by Kappa coefficient test.Finally,according to correlation test results,the impacts of pre-operation NSA,MC,ME,age,pattern of internal fixation and post-operation imaging indexes were evaluated separately using binary logistic regression analysis.Results:Six randomized controlled trials were included in our study.The results showed that intramedullary nails are superior to locking plates in the treatment of proximal humeral fractures with regards to external rotation,impingement syndrome,and screw cutout.All radiologic indices showed moderate or high reliability.The correlation coefficient of NSA,MC,ME were 0.864,0.874 and 0.695 respectively.And MC presented statistic differences of median between two imaging approach.In addition,the Kappa coefficient of NSA,MC and ME were 0.670,0.720 and 0.500 separately.According to Kappa agreement classification,there is a high agreement in NSA or MC and moderate in ME.Binary logistic regression was used to evaluate the factors impacting postoperative NSA,indicating that only preoperative abnormal NSA was the risk factor affecting postoperative NSA reduction.Conclusions:Intramedullary nails are superior to locking plates in external rotation and certain complications.Our retrospective study showed NSA has high agreement and correlation between two imaging exams.However,the difference of MC and ME might lead to inaccurate judgment to surgery indications and fracture severity in single imaging test.Additionally,preoperative abnormal NSA impact postoperative normal reduction of NSA and it deserved more attention in surgery for surgeons.