Great and extensive progress has been made in joint surgery in the last decade. With the evolution of surgical concepts and the development of operational technique and equipment, indications, selective range for surgica l operation and management in the period of perioperation have been surveyed in new perspectives and with deeper insights. This article introduces the situation of joint surgery of China in these years, briefly reviews the latest progresses in the fields of the arthroscopy, the arthroplasty and the joint cartilage repa ration, and thus suggests developmental strategies for Chinese joint surgery in the future.

BACKGROUND:The main factors that influence revision of acetabular bone defects include evaluation of acetabular bone defects,reconstruction of acetabulum and appropriate acetabular cups used in revision.OBJECTIVE:The review from the three aspects will help to choose an appropriate cup in revision and to formulate the best revision protocols.METHODS:A computer-based online search of PubMed was performed for English articles published from January 1900 to June 2009 with the key words of acetabulum,revision,bone defect,in English and Chinese.Clinical studies published in core periodicals of the latest twenty years were reviewed.Articles regarding primary joint replacement,femoral prosthesis revision and animal experiments were excluded.RESULTS AND CONCLUSION:A total of 61 articles were analyzed,31 were excluded,and 30 mainly published in 5 years,were included.Reconstruction of acetabular bone structure,restoration of original rotation center of hip joint are key factors for repair.Moreover,appropriate prosthesis further benefits the repair effect.Bone transplantation for bone defect and cementedless prosthesis have become favorable methods for revision of acetabular bone defects.

Objective To assess the predictive and prognostic role of the alteration of serum carcinoembryonic antigen (CEA),squamous cell carcinoma antigen (SCC-Ag) and cytokeratin 19 fragment (CYFRA21-1) during chemotherapy in patients with advanced esophageal squamous cell carcinoma (ESCC).Methods The serum levels of CEA,CYFRA21-1 and SCC-Ag were measured in 50 patients with advanced ESCC at baseline and after first line chemotherapy.The data was correlated with objective efficacy and overall survival.To evaluate the role of tumor marker change in predicting response to therapy,receiver operating characteristic (ROC) curves were constructed.Results CEA,SCC-Ag and CYFRA21-1 increased higher than the cutoffs in 22.0 %,34.0 %,and 44.0 % of tested patients,respectively.Statistically significant correlations were observed between CYFRA21-1 and SCC responses and objective efficacy evaluated by RECIST criteria (Z =3.181,2.389; P = 0.001,0.017).Based on the ROG curve analysis,a post treatment 32 % and 38 % increase in serum concentration was used as cut-off level for defining CYFRA21-1 and SCC-Ag change,respectively.When the cut-off levels were used to predict chemotherapy efficacy,the accuracy for CYFRA21-1 and SCC-Ag were 76 % and 70 %.In the univariate survival analysis,a statistically significant prognostic impact on survival from the change of CYFRA21-1 and SCC-Ag was observed.Conclusion CYFRA21-1 and SCC-Ag are useful for diagnosis,predicting chemotherapy objective efficacy and prognosis in advanced ESCC.

AIM:To explore the surgical effect of total hip joint replacement on the severe degenerative arthritis secondary to congenital hip dysplasia.METHODS:The experiment was carried out in the Department of pedics,General Hospital of Chinese PLA between June 1998 and December 2005.①116 adult patients(128 hips) with arthritis secondary to dysplastic hip received total hip replacement,including 13 males(15 hips) and 113 females(106 hips),aged from 16 to 66 years(average of 42.6 years).According to Crowe classification system,there were 57 cases(60 hips) of typeⅠ,20(23 hips) of typeⅡ,16(20 hips) of type Ⅲ and 23(25 hips) of type Ⅳ.②The acetabula were reconstructed at the true acetabular location.Except one case,all patients were given biological fixation of cementless acetabular cups including 83 hips with routine total hip replacement,and 27 hips with smaller cup;11 hips with routine total hip replacement after granular bone grafting,and 7 hips with a smaller cup after autologous femoral grafting on the superior margin of acetabula.119 biological prostheses were used to reconstruct the femoral cups including 4 common cemented shafts,6 long cemented shafts,and 4 S-ROM prostheses.③Harris hip score was adopted to evaluate the hip function,and X-ray photographs were used to observe the location of prostheses.RESULTS:①The Harris hip scores increased from 38.5 preoperatively to 88.5 postoperatively.②No prosthesis displacement,dislocation of hip joint or repair was found in patients,and the length of treated limbs meanly prolonged by 2.3 cm.Additionally,the incision healed primarily.③Radiographically,the positions of the prostheses were normal,and the bone grafts fused with the host bone successfully.The average bone coverage was 95%(90%-100%);radiolucentline was observed at between the acetabular cup and host acetabula in 2 cases,and 1 at femur.④Adverse effects:Sciatic nerve tension injury was found in 1 case and recovered in 4 months,the femoral nerve tension injury in 1 case and recovered in 3 months,and hip rest pain remained in 4 cases.CONCLUSION:In the treatment of arthritis secondary to dysplastic hip with total hip replacement,it is better to reconstruct the acetabulum at the true acetabular location.Moreover,the individualized appropriate selection of femoral prostheses is a key factor to obtain good curative effects.

OBJECTIVEThis study aims to do the following: construct a three-dimensional finite element model of an labial inverted impacted maxillary central incisor and its supporting tissues, analyze stress distribution in the periodontal tissue when various tractions are exerted, and provide references for treating impacted maxillary central incisor.

METHODSA three-dimensional finite element model oflabial inverted impacted maxillary central incisor and its periodontal tissues was established using Mimics 10.01 and Ansys 14.0 software based on original cone beam computed tomography (CBCT) data. Various traction values (20, 30, 40, 50, 60, and 70 g) were exerted on the incisal margin in the direction perpendicular to the impacted tooth. Different Von Mises stress values were determined.

RESULTSStress distribution on the periodontal ligament increased with traction size. When 30 g traction was exerted on the labial inverted impacted maxillary central incisor, the Von Mises stress was 24 919.0 Pa, which was within the range of the optimum force and close to its maximum value.

CONCLUSIONThe optimum traction for early orthodontic treatment of labial inverted impacted maxillary central incisor is nearly 30 g.

ObjectiveTo investigate the changes of hepatitis B sarfaceantigen (HBsAg) titer in hepatitis B e antigen (HBeAg) positive chronic hepatitis B (CHB) patients treated with nucleos(t)ide analogs and pegylated interferon alfa-2a (PEG IFNα-2a) sequential therapy.Methods Among 6 HBeAg positive CHB patients,3 patients were treated with nucleos(t)ide analogs followed by PEG IFNα-2a for 48 weeks,3 patients were treated with nucleos(t)ide analog monotherapy.The serum HBsAg,anti-HBs,HBeAg,anti-HBe andanti-HBcweredetectedusingthetime-resolved immunofluorometric assay and serum hepatitis B virus (HBV) DNA levels were determined by Taqman polymerase chain reaction (PCR) every 12 weeks.Results HBsAg loss were achieved in three patients after 48-week nucleos(t)ide analogs and PEG IFNα-2a sequential therapy.However,the HBsAg titers of another 3 patients varied from 100 IU/mL to 320 IU/mL.ConclusionIn HBeAg positive CHB patients who obtain virologic response accompanied with HBsAg titer decreasing dramatically by nucleos(t) ide analog treatment,PEG IFNα-2a sequential treatment can increase HBsAg clearance rate.

OBJECTIVE: To evaluate the histocompatibility of poly (lactic-co-glycolic acid)/RNA Ⅲ inhibiting peptide (PLGNRIP) sustained release microspheres.METHODS: The crude peptide comprising N to C-terminals was synthesized using Fmoc method. The crude synthetic RNAⅢ peptide was purified by reverse phase high performance liquid chromatography, followed by component harvesting according to ultraviolet absorption peak, and freeze-drying. PLGNRIP sustained release microspheres with a diameter of 50-70 pm were prepared using liquid-phase multiple emulsion method. The histocompatibility of PLGNRIP sustained release microscopes were preliminarily evaluated through the use of acute general toxicity test, MTT cytotoxicity test, intramuscular implantation test, sensitivity test, and pyrogen test.RESULTS: Acute general toxicity test results showed that all included animals survived and presented with no toxicosis reaction and obviously changed body mass. MTT cytotoxicity test results revealed that the average relative growth rate of cells from two eluents was over 85%, with cytotoxicity grade 1, which indicated no cytotoxicity. Intramuscular implantation tests showed that at 4 weeks after implantation of RiP powder or PLGNRIP microscopes, no obviously congested, degenerated, or necrotic tissue was observed. All RIP powder and a part PLGNRIP microscopes were degraded. Fibroblasts accounted for a large proportion in all cells. NO inflammatory cell infiltration, involving neutrophits and multinucleated giant celts, was observed. Sensitivity test rasults displayed that the average primary irritation index was 0.38, 0.33, arid 0.31 in the eluent stock solution, 2% dinitoflruorobenzene, and physiological saline-administerd groups, respectively. Pyrogen test results showed that fervescence of each rabbit in the experiment was under 0.5 ℃ and the sum of fervescence was under 1.3 ℃ .This is in coincidence with evaluation criteria of pyrogen test.CONCLUSION: PLGNRIP sustained release microspheras exhibit good histocompatibility.

BACKGROUND:Alternative implants affect stability of prostheses,and freeze-dried bone allografts are most selected as implants.The crack between grafts and host bone is unavoidable,which would weaken the bone integration.Bone cement can fill the cracks quickly and completely,however,the effects of bone cement on the stress of prostheses and its own remains poorly understood.OBJECTIVE:To evaluate the effect of the different grafting for bone loss in the presence of the new acetabular component with wings at the time of acetabular revision.METHODS:The finite-element models of acetabular component with three wings and acetabulum with bone loss were established.Following prostheses implantation,the gaps were filled with bone cement and freeze-dried bone allograft,respectively,stress of the graft and its effect on prostheses were analyzed under 2 158 N and 426 N acetabular loads.RESULTS AND CONCLUSION:The finite-element analysis demonstrated that stress and strain at the interfaces of bone-shell and metal-polyethylene liner had the same direction of change but no significant difference between them.In the study,the result indicated increased contact stresses with an increased hip force and orientation.The stress of wings increased gradually from rim to root.Its peak stress was at the joint between the wing and the shell.The different grafts did not affect the stress of the acetabular component.But the stress of bone cement was significantly higher than that of particulate bone.The study demonstrated that change of the graft could not make remarkable effect on the stress of the acetabular component.But the stress of bone cement increased significantly.The result of the finite-element analysis indicated that particulate bone graft is benefit to improving itsstability and to minimize aseptic loosening rate of acetabular component.

OBJECTIVE: To evaluate blood compatibility of polyaiticglycolic acid/RNA Ⅲ inhibiting peptide (PLGA/RIP) delayed release microspheres.METHODS: ① Preparation of PLGA/RIP microspheres: The solid-phase synthesis (Fmoc) method was used to synthesize RIP crude sample from C end to N end; the synthesized crude peptide was purified by the reverse phase high performance liquid chromatography. According to UV absorption peak, the components were collected and freeze-dried, to obtain RIP purifications. Then liquid-phase multiple emulsion method was used to prepare PLGA/RIP microspheres at the diameter of 50-70 μm. ② Preparation of eluent: The PLGA/RIP microsphere powders were eluted with sterile physiological saline at 37 ℃, to prepare 1 g/L eluent; then 0.5 g/L eluent was obtained adding equal volume of sterile physiological saline. The hemolysis test, blood clotting test, and platelet aggregation test were conducted to measure prothrombin time and activated partial thromboplastin time, to observe the influence on rabbit leucocytes, erythrocytes and thrombocytes, and to preliminarily evaluate the blood compatibility of PLGA/RIP microspheres. RESULTS: ①The haemolysis rates of eluent stock solution and 0.5 g/L eluents were 3.24% and 2.67% respectively, which were in coincidence with the criteria of medical biomaterials, less than 5%. ② The eluent stock solution and 0.5 g/L eluents of PLGA/RIP microspheres had no significant effect on rabbit clotting time, prothrombin time and activated partial thromboplastin time, the number of rabbit leucocytes, erythrocytes and thrombocytes, as well as platelet aggregation.CONCLUSION: PLGA/RIP delayed release microspheres have a good blood compatibility.

Alternative designs have been explored in an attempt to improve the longevity of acetabular prostheses in revision surgery. Many studies had been designed to test the result of the extra-large uncemented hemispherical acetabular components used for acetabular revision in the presence of bone loss. A clinical study of a new acetabular component consisting of a porous metal shell with three wings and an all-polyethylene liner had attained a satisfying result. The purpose of this study was to evaluate the new acetabular component by comparison with the hemispherical acetabular component. The finite-element models of the two acetabular components and the acetabulum in the presence of bone loss were established to calculate the interface stresses during a normal gait cycle with use of the finite-element formulations. Results of the finite-element analysis demonstrated that stress and strain of the two acetabular components had the same direction of change, but the new component had higher stress at the root of wings. In the study, the result indicated reduced contact stresses with a reduced abduction angle of wings. The stress was lower in the new acetabular component of 15° angle of wings compared with the new acetabularcomponent of 30°of wings and hemispherical acetabular component (P < 0.05). The stress of acetabular component with wings showed no remarkable difference by comparison with the extra-large uncemented hemispherical acetabular component. Reducing abduction angle of wings seemed to be a viable means of reducing the stress of the acetabular component while improving its stability.