Coagulation Factors for Diagnosis of Periprosthetic Joint Infection / 中山大学学报(医学科学版)

ObjectivePeriprosthetic joint infections （PJI） are currently the most calamitous complication after arthroplasty. Although achievements have been made in many markers for the diagnosis of PJI， the lack of a gold standard remains a great obstacle for early diagnosis. This study aimed to investigate the association between coagulation markers and the development of PJI in patients undergoing revision total joint arthroplasty （TJA）. MethodsWe conducted a retrospective cohort study with a total of 2 517 patients who underwent hip or knee arthroplasties from January 2011 to January 2022 （2 394 with primary TJA， 87 with aseptic revision and 36 with PJI）. We applied univariate analysis and multivariate logistic regression to analyze differences of coagulation factors between primary TJA and aseptic revision or PJI group. Receiver operating characteristic （ROC） curve and area under the curve （AUC） were used to measure the diagnostic value of coagulation factors in predicting PJI. ResultsCoagulation factors and their ratios including plasma fibrinogen （FBG）， prothrombin time （PT）， thrombin time （TT）， activated partial thromboplastin time （APTT）， platelet （PLT）， mean platelet volume （MPV）， platelet distribution width （PDW）， plateletcrit （PCT）， PLT / MPV， PLT / PDW and PLT / PCT were included in this study. High FGB level was strongly correlated with the risk of PJI compared to other coagulation factors. The optimal threshold value of FBG was 4.53 g/L with a sensitivity of 47.22%， a specificity of 93.07% （Primary TJA group vs. PJI group）. Similarly， the optimal threshold value of FBG was 4.44 g/L with a sensitivity of 47.22%， a specificity of 95.40% between the other two groups （Aseptic revision group vs. PJI group）. ROC curve analysis demonstrated moderate diagnostic performance of FBG （AUC value）， indicating a potential to be a diagnostic marker for PJI. ConclusionsFBG is significantly correlated with PJI and it can be used as a potential non-invasive marker for early detection. It may serve as a safe and cost-effective tool for assessing PJI in clinical work.

Clinical analysis of revision after primary hip replacement in the early stage / 中华外科杂志

<p><b>OBJECTIVES</b>To analyze the reason of revisions no more than 5 years after primary hip replacement, and to discuss the methods how to prevent and manage.</p><p><b>METHODS</b>Retrospectively review 11 cases with revision no more than 5 years after primary total hip replacement from January 2002 to June 2007. The reasons for revision were as follows: 2 cases were recurrent dislocation due to malposition of acetabular prosthesis; 5 cases were loosening of acetabular prosthesis; 1 case was abrasion of the native acetabulum by bipolar femoral head; 2 cases were periprosthetic femoral fractures and 1 case was periprosthetic infection. The average follow-up time was 36 months. Each patient was assessed according to Harris hip score. The revision procedures including liner only, acetabular prosthesis only, or both acetabular prosthesis and femoral prosthesis depending on the reasons for revision, two-stage revision was performed on 1 case with periprosthetic infection.</p><p><b>RESULTS</b>The average of Harris hip score was increased from 46 (28 to 62) preoperatively to 86 (75 to 96) at follow up. The complication occurred in 2 cases: one was postoperative haematoma formation who was performed further surgery for clearance of haematoma, another was slight instability of the hip joint who was accepted skin traction for 3 weeks.</p><p><b>CONCLUSIONS</b>The main reason for revision after primary total hip replacement is related to uncorrected insert of acetabular prosthesis. Improving surgical technique of insert of acetabular prosthesis is important in primary total hip replacement.</p>

Reconstruction of anterior cruciate ligament with hamstring tendon autografts under arthroscopy / 中国骨伤

<p><b>OBJECTIVE</b>To evaluate therapeutic effects for reconstruction of anterior cruciate ligament(ACL)with hamstring tendon autografts and bioabsorbable interference screws fixation under arthroscopy.</p><p><b>METHODS</b>Thirty-one patients with ACL rupture were verified through arthroscopy. There were 27 patients were male and 4 patients were female, ranging in age from 17 to 40 years,with an average of 25 years. Among the patients, 26 patients combined with meniscus injuries, 3 patients with injuries of articular cartilage and 16 patients with I to II degree degeneration of articular cartilage. All the patients were performed ACL reconstruction with hamstring tendon autografts under arthroscopy and the reconstructed ligaments were fixed with bioabsorbable interference screws.</p><p><b>RESULTS</b>No severe complications occurred at early stage after operation. Thirty patients were followed up and ranged from 9 to 39 months,with an average of (19 +/- 9.0) months. Lysholm score significantly increased from average of 54.6 +/- 16.6 preoperatively to average of 92.5 +/- 5.7 at the end of follow-up period (t = 11.84, P < 0.01). Twenty-six patients restored to normal activity.</p><p><b>CONCLUSION</b>ACL reconstructed with hamstring tendon autografts under arthroscopy has advantages of minimal trauma and satisfactory outcomes.</p>

Construction and identification of human bone morphogenetic protein-7 recombinant adeno-associated virus type 2 vector and its expression in bone mesenchymal stem cells / 中华外科杂志

<p><b>OBJECTIVES</b>To facilitate gene therapy research using recombinant adeno-associated virus type 2 (rAAV2) vector as gene transfer vehicle, and to construct a rAAV2 based vector carrying bone morphogenetic protein-7 (BMP7) and observe its expression in bone mesenchymal stem cells.</p><p><b>METHODS</b>The coding sequence (1.3 kb) of BMP7 was amplified by polymerase chain reaction (PCR) from the pcDNA1.1(+) plasmid containing the human BMP-7 cDNA. After purified, the gene fragment was cloned into a plasmid pUC18 and termed plasmid pUC18-hBMP7. The recombinant pUC18-hBMP7 was digested by Kpn I and Sal I and further ligated to the pSNAV by T4DNA ligase. The resultant plasmid PSNAV-hBMP7 was transformed into DH5a Escherichia coli, and positive colonies were screened by PCR and digest with restriction enzyme to identify the correct recombinant clones. BHK-21 cells were transfected with the purified pSNAV-BMP7 plasmid according to a standard calcium phosphate precipitation method. The cells were then cultured in selection media containing 800 micro g/ml G418 (Gibco/BRL). G418-resistant BHK-21 cell clones were isolated and the integrity of hBMP7 gene was determined by PCR using the above PCR primers. To package the virus, stably transfected BHK-21 cells were subsequently infected with recombinant herpes simplex virus type 1 (rHSV-1). The collected cells were processed by chloroform treatment, PEG8000/NaCl precipitation and chloroform extraction for purification. The titer was determined using quantitative DNA dot blots and the purity was examined by sodium dodecyl sulphate polyacrylamide gel electrophoresis. Following infection with rAAV2-BMP7 at multiplicities of infection of 1 x 10(5) vector genomes per cell and subsequent culture, MSCs were assessed qualitatively for BMP7 production.</p><p><b>RESULTS</b>Transient transfection showed an efficiency of 98.8% in MSCs. RT-PCR showed that MSCs had transcription of BMP7 that was enhanced by the gene transfer. BMP-7 expression in MSCs was identified by Western-blot.</p><p><b>CONCLUSIONS</b>The hBMP7 recombinant adeno-associated virus vector is successfully constructed. The present in vitro study demonstrates that rAAV2-BMP7 could infect MSCs.</p>