Effect of Femoral Resection on Coronal Overall Alignment after Conventional Total Knee Arthroplasty

Background：A good postoperative alignment in total knee arthroplasty （TKA） is the key to achieving satisfactory results.We assessed the effect of femoral and tibial resection on the overall alignment after conventional TKA.Methods：We conducted a retrospective analysis of 212 primary TKAs in 188 patients.Intramedullary （IM）-guided resection was applied on the femoral side while extramedullary （EM）-guided resection was used on the tibial side.Using full-length X-ray,the preoperative femoral valgus angle and lower extremity alignment,as well as 2-week postoperative femoral and tibial prosthetic coronal alignment and overall lower extremity alignment,were measured.Results：Postoperatively,good prosthetic alignment was achieved in 191 cases （90.1%） on the tibial side and in 144 cases （67.9%） on the femoral side （χ^2 =5.441,P =0.02）.Multiple linear regression analysis was used to assess the effect of different alignment sides on the overall alignment in the coronal plane.Data were divided into five subgroups based on the valgus or varus status of the prostheses.The standardized regression coefficients of the femoral and tibial prosthetic alignment on the overall alignment were 0.666 and 0.414,respectively;in varus on both sides were 0.658 and 0.377,respectively;in valgus,0.555 and 0.030;femoral side varus and tibial side valgus,0.702 and 0.211;femoral side valgus and tibial side varus,-0.416 and 0.287.The study showed that the overall low extremity alignment was statistically influenced by the prosthetic alignment,except for the tibial prosthetic alignment when femoral prosthesis was in valgus （P =0.153）.Conclusions：In conventional TKA,tibial side EM-guided resection may offer satisfactory postoperative alignment,and femoral resection relying on IM guide may lead to more undesirable results.Postoperative coronal alignment is mainly affected by the femoral resection.Therefore,femoral side operation should receive adequate attention from the surgeons.

Aryl hydrocarbon receptor expression in serum,peripheral blood mononuclear cells,and skin lesions of patients with atopic dermatitis and its correlation with disease severity

Background:The aryl hydrocarbon receptor(AhR)is a ligand-activated transcription factor,which is critically involved in the pathogenesis of a variety of skin diseases.The aim of this study was to detect AhR and its downstream regulators including cytochrome P450(CYP1A1),AhR nuclear translocation(ARNT),and aryl hydrocarbon receptor repressor(AhRR)in serum,peripheral blood mononuclear cells(PBMCs),and skin lesions in patients with atopic dermatitis(AD).Methods:Twenty-nine AD patients defined according to the criteria of Hanifin and Rajka and Chinese criteria of AD were included.Subjects without allergic and chronic diseases were recruited as controls.Patients and controls were selected from the dermatology outpatient clinic of Peking University People’s Hospital from August 1 to December 31 in 2018.Enzyme-linked immunosorbent assay was performed to detect serum AhR level.ThemRNA of AhR,AhRR,ARNT,and CYP1A1 in PBMCs were measured by realtime quantitative polymerase chain reaction.AhR expression in skin lesions was measured by immunohistochemistry.Results:AhR was significantly higher expressed in serum(41.26±4.52 vs.33.73±2.49 pmol/L,t=6.507,P<0.001)and skin lesions(0.191±0.041 vs.0.087±0.017,t=10.036,P<0.001)of AD patients compared with those of controls.The mRNA levels of AhR(1.572±0.392 vs.1.000±0.173,t=6.819,P<0.001),AhRR(2.402±1.716 vs.1.000±0.788,t=3.722,P<0.001),CYP1A1(2.258±1.598 vs.1.000±0.796,t=3.400,P=0.002)in PBMCs of AD patients were higher compared with those of controls.The difference in mRNA levels of ARNT was not statistically significant between the patients and controls(1.383±0.842 vs.1.000±0.586,t=1.653,P=0.105).AhR mRNA levels in PBMCs positively correlated with eczema area and severity index score and serum interleukin-6 levels.Conclusion:AhR and its downstream regulators were highly expressed in serum,PBMCs,and skin of AD patients,which might contribute to the pathogenesis of AD.

Type I Neurofibromatosis Associated with Hypereosinophilic Syndrome: A Rare Case Report

Introduction Hypereosinophilic syndrome (HES) encompasses a group of disorders characterized by marked peripheral blood eosinophilia,tissue eosinophilia,or both,resulting in organ damage attributable to the eosinophilia.Type Ⅰ neurofibromatosis (NF-I) is an autosomal dominant genodermatosis with an increased risk of developing malignancies.1 HES was also considered as paraneoplastic presentation and it is proved to arise in combination with hematological malignancies such as chronic myeloid leukemia (CML),acute lymphocytic leukemia (ALL),and non-Hodgkin lymphoma (NHL).2 Here,we have reported a rare case of HES associated with NF-I that has not been reported so far,which may improve the knowledge of association between NF-1 and hematological malignancies.