We review the literature about Heterotopic Ossification (HO) and introduce its pathophysiology, classification, incidence, clinical presentation, diagnosis, prophylaxis and treatment in this article. HO is the presence of bone in soft tissue where bone normally does not exist. Mature HO has the same morphology as callus. It is considered that 3 conditions are necessary for HO: osteogenic precursor cells, inducing agents, and a permissive environment. Fever, swelling, erythema, and occasional joint tenderness appear in the early stage of HO. The most sensitive imaging modality for early detection of HO is three-phase bone scintigraphy which can also monitor the metabolic activity and degree of maturity of HO. Non-steroidal antiinflammatory drugs (NSAIDs) are the most effective for the prophylaxis of HO after the operation of hip replacement or acetabulum fracture. Surgical resection is the only treatment for patients with severe joint tenderness following HO.

Objective To evaluate the secondary internal fixation plus bone grafting for salvage of failed internal fixation for intertrochanteric hip fractures. Methods Between January 2001 and March 2008, 25 patients with intertrochanteric fractures who had suffered from failed initial internal fixation were treated with secondary open reduction and internal fixation and bone auto grafting. They were 15 men and 10 women, with a mean age of 50 (17 to 72) years. The mean interval between the initial operation and the revision was 12 (4 to 27) months. The failure of original internal implants involved the dynamic hip screw (DHS) in 12 patients, the dynamic condylar screw (DCS) in 3, the angular blade plate (ABP) in 1, the cephalomedullary nail in 3 and the cannulated screw in 6. The replacement of internal implants included PFN in 12 eases, DCS in 7, DHS in 4 and ABP (95°) in 2. Results The mean follow-up was 24 (6 to 84) months. The revisions were uneventful. Of the 25 nonunions, 24 healed (96.0%). The postoperative mean hip rating (Harris score) for the hip joint was 87(35 to 100) points. The X-ray films at the last follow-up revealed the coLlodiaphyseal angle averaged 120° ( 110° to 140°). No avascular necrosis of the femoral head or hip degeneration was found. Conclusion In properly selected patients, secondary internal fixation with bone grafting for failed open reduction and internal fixation of intertrochanteric hip fractures can provide a high rate of union and good clinical results with a low rate of complications.

Objective To classify tibial plateau fractures based on the analysis of the morphology and injury mechanisms of 200 cases of tibial plateau feature.Methods We collected the X-ray and CT images of 200 consecutive cases of tibial plateau fracture in i99 patients who had been treated at our department from January 2010 to April 2011.They were 134 males and 65 females,from 15 to 77 years of age (average,45.7 years).According to the Schatzker classification,9 cases were type Ⅰ (4.5％),105 type Ⅱ (52.5％),19type Ⅳ (9.5％),37type Ⅴ (18.5％),30type Ⅵ (15.0％),and none type m.The fracture morphology and injury mechanism of each case were analyzed to propose a new classification system.Results Fractures of tibial plateau can be classified into the following five types:(a) Lateral condylar fracture and valgus injury (100 cases,50％).The injury mechanism is the axial force on the valgus and extended knee joint.(b) Fracture-dislocation injury (24 cases,12.0％).This type includes typical Schatzker type Ⅳ,and some cases of Schatzker type Ⅵ associated with lateral subluxation.Its mechanism is a compound force of valgus,varus,rotational and axial stresses.The rotational force is the key factor leading to subluxation of the knee joint.(c) Double-condylar fracture (40 cases,20.0％).This type is caused by an axial force on the extended knee,including Schatzker type Ⅴ and some cases of Schatzker type Ⅵ not associated with knee subluxation.(d) Posterior condylar fracture and flexion injury (32 cases,16.0％).This type only involves the posterior condylar plateau,and is caused by an axial force on the flexed knee.Based on the morphology,posterior condylar fractures can be further divided into three subtypes:simple split of posteromedial condyle,simple collapse of posterolateral condyle,and a combination of the two.(e) Frontal plateau compression fracture and hyperextension injury (4 cases,2.0％).This type is caused by an axial force on the hyper-extended knee.It is characterized by significant compression of the anterior plateau and intact posterior plateau.Conclusion Based on the morphological features and injury mechanisms,tibial plateau fractures can be classified into 5 types:lateral condylar fracture,fracture-dislocation injury,double-condylar fracture,posterior condylar fracture,and frontal plateau compression fracture.

OBJECTIVE To investigate the distribution and drug resistance status of extended-spectrum ?-lactamases producing(ESBLs) Klebsiella pneumoniae and to provide the basis for clinic anti-infective treatment.METHODS To use ATB-expression analyzer to identify the microbe.The drug susceptibility was tested with the K-B method and the ESBLs producing strains detected by diffusion confirmed test.RESULTS Among 137 strains of identified K.pneumoniae,34.3% of them(47 strains)produced ESBLs,and most had been shown in geriatrics ward.The drug resistance rate of ESBLs producing K.pneumoniae was higher than that in non-producing ESBLs one.So imipenem should be considered to be a preferred antibiotic when used on K.pneumoniae seriously infected cases.CONCLUSIONS The drug resistance of K.pneumoniae is a serious problem,we should pay attention on the status of ESBLs distribution,based on the susceptibility to choose the reasonable antibacterial to avoid the producing ESBLs bacteria spread out.

OBJECTIVE To investigate the drug resistance of ESBLs-producing Escherichia coli and Klebsiella pneumoniae in local nosocomial infection,for guiding the clinical drug resistance. METHODS ATB analysis system was used for identification of bacteria,extra-susceptibility tests were detected by K-B method. RESULTS The isolation rate of ESBLs-producing E. coli and the K. pneumoniae was 29.9% and 30.8%,respectively. The drug susceptibility was indicated the resistance rate of ESBLs producing strains to antibacterial agents except imipenem was higher than that of non-ESBLs producing strains. CONCLUSIONS Detecting drug resistance of ESBLs producing strains is of important significance for guiding the clinical rational use of antibacterials and controling the epidemics.

OBJECTIVE To investigate the drug resistance of ESBLs-producing Escherichia coli in community-acquired urinary tract infection for guiding the clinical drug-using.METHODS ATB-Expression analysis system was used for identification of bacteria,extra-susceptibility tests were detected by K-B method.RESULTS Totally 104 E.coli strains were detected,the isolation rate of ESBLs-producing E.coli was 13.5%,the resistant rates of E.coli were up to 70% to ampicillin,piperacillin and Co-trimoxazole,the resistant rate was up to 55% to ciprofloxacin and levofloxacin,and the susceptible rate was 100% to imipenem.CONCLUSIONS The E.coli is a main pathogen in community-acquired urinary tract infection,Its drug resistance is extremely severe.To enhance detecting drug resistance of pathogenic bacteria is of important significance for guiding the clinical rational drug-using and reducing drug-resistant strains.

Objective:To investigate the med- to long-term clinical outcomes of open reduction and cannulated screw fixation via the modified Smith-Petersen approach for irreducible femoral neck fractures in young adults.Methods:The clinical data of 16 young adults were retrospectively studied who had been treated for irreducible femoral neck fractures by open reduction and cannulated screw fixation via the modified Smith-Petersen approach by the same surgeon from December 2009 to February 2015 at Department of Orthopaedics and Traumatology, Beijing Jishuitan Hospital. There were 11 males and 5 females aged from 19 to 59 years (average, 42.9 years). All their fractures were closed Garden type Ⅳ, with high energy injury in 8 cases and low energy injury in the other 8 ones. The time from injury to surgery averaged 5.4 d (from 1 to 11 d). In all the patients, open reduction and cannulated screw fixation via the modified Smith-Petersen approach was conducted after ideal reduction had not been achieved by 3 continuous attempts in primary closed reduction in a traction bed. Recorded were the postoperative full weight-bearing time, return to work time, fracture union time, function of the affected hip and complications at the last follow-up in the patients.Results:The 16 patients were followed up for 6 to 12 years (average, 8.8 years). The postoperative full weight-bearing time averaged 12.7 weeks (from 2 to 16 weeks) in 16 patients; the return to work time averaged 15.0 weeks (from 3 to 20 weeks) and the fracture union time 3.5 months (from 3 to 6 months) in 15 patients while fracture nonunion happened in the other one. The HSS hip scores at the last follow-up averaged 90.3 points (from 62 to 98 points), yielding 12 excellent, 2 good, one fair and one poor cases. The one case with fracture nonunion underwent total hip arthroplasty (THA); of the 4 cases with avascular necrosis of the femoral head, 2 underwent THA; limited range of hip motion due to heterotopic ossification was noted in one case.Conclusion:Open reduction and cannulated screw fixation via the modified Smith-Petersen approach may lead to fine med- to long-term clinical outcomes in young adults whose femoral neck fracture cannot be reduced by closed reduction, because the modified Smith-Petersen approach allows fracture reduction under direct vision.

【Objective】 To retrospectively analyze the serological and nucleic acid testing(NAT) data of voluntary blood donors from six blood banks in Tibet, in order to explore the positive impact of NAT on reducing the risk of infective transfusion in a regional scope. 【Methods】 From 2018 to 2022, 38 718 voluntary blood donors from blood centers of Tibet, Shannan, Shigatse, Naqu, Nyingchi and Ngari were tested for hepatitis B virus surface antigen (HBsAg), hepatitis C virus antibody (anti-HCV), human immunodeficiency virus antigen (HIV) and antibody (Ag/Ab1+2) serological determination by enzyme-linked immunosorbent assay (ELISA). At the same time, Haoyuan and Daan nucleic acid detection systems were used for the combined detection of HBV-DNA, HCV-RNA and HIV-RNA. The results of NAT of reactive ELISA samples were statistically analyzed. 【Results】 A total of 178 ELISA-/NAT+ samples were detected in Tibet over the past five years, including 170 HBV-DNA positive cases, 8 HCV-RNA positive cases, and 0 HIV-RNA positive cases, with the positive rate at 0.460%.The detection rate of 624 ELISA+/NAT+ samples was 1.61%.The age of blood donors with hepatitis B in Shigatse area was slightly higher than that in other areas, and the difference was statistically significant(P<0.05) . 【Conclusion】 The centralized detection of viral nucleic acid in Blood Center of Tibet Autonomous Region can effectively reduce the missed detection of transfusion transmitted diseases and guarantee the blood safety in the region.