Background: Posterior pedicle screw fixation had been applied to maintain spinal stability and avoid further nerve damage in thoracolumbar fracture. This study aimed to evaluate the efficacy of short-segment posterior fixation with monoaxial pedicle screws versus polyaxial pedicle screws in treating thoracolumbar fracture.Methods: A total of 75 patients with thoracolumbar fracture who underwent short-segment posterior fixation with monoaxial pedicle screw (group A) or polyaxial pedicle screw (group B) were retrospectively enrolled. The patient demographic and radiological data were analyzed between the two groups.Results: A total of 63 patients with an average age of 44.7±11.5 years were finally recruited in this study.There were no significant differences in age, gender, fracture level, thoracolumbar injury classification and severity scale (TLISS) score, American Spinal Injury Association (ASIA) score, Arbeitsgemeinschaft für Osteosynthesefragen (AO) classification, and hospital stay between the two groups (P>0.05). At the last follow-up, the prevertebral height ratio and normal-to-injured vertebral height ratio were significantly decreased in group A compared to group B (P=0.027 and P=0.007, respectively).Conclusions: Short-segment posterior fixation with monoaxial or polyaxial pedicle screw for fractured thoracolumbar vertebra can restore injured vertebral height. Compared with polyaxial pedicle screw, monoaxial pedicle screw endows stronger leverage which is more beneficial for restoring injured vertebral height and recovery of the damaged endplate in thoracolumbar short-segment posterior fixation.

Background: Infection, including mixed infection, is not uncommon in orthopedic surgical incision. This study aimed to investigate the epidemiology and drug resistance of mixed infections after orthopedic surgical procedures. Methods: We retrospectively analyzed 533 orthopedic surgical site infections (SSIs) in a university hospital from 2012 to 2017. Eighty-six patients (218 strains) with bacterial culture results showing more than one strain were screened to explore their epidemiology and drug resistance. Results: Of 218 bacterial strains, 2-7 bacterial infections were noted in each wound. Most infections were caused by two kinds of bacteria (65.1%). The number of infections decreased with increased number of strains. The combinations of pathogenic microorganisms were all gram-negative, 55.81%; gram-positive and gramnegative, 30.23%; all gram-positive, 12.79%; and gram-positive and fungi, 1.16%. Their resistance is consistent with the bacterial resistance of 447 cases of single bacterial SSI during the same period. Hospitalization duration was longer (9.8-20.6 d). Conclusion: Our study shows no significant changes in epidemiology and drug resistance caused by mixed infections in the orthopedic surgical site because of coordination and competition among microorganisms. These bacteria are difficult to control, leading to extended hospitalization. Antibiotic agents should be chosen strictly according to drug sensitivity, and ineffective antibiotic agents must be avoided.

Purpose: To evaluate the use of short-segment posterior fixation with monoaxial and polyaxial pedicle screws in thoracolumbar fractures Methods: All patients who underwent short-segment posterior fixation with monoaxial pedicle screws or polyaxial pedicle screws in the injured vertebra of a thoracolumbar fracture (T12-L2) in our hospital between June 2012 and December 2018 were categorised into two groups: monoaxial pedicle screws group (group A) and polyaxial pedicle screws group (group B). We compared the Thoracolumbar Injury Severity Score (TLISS), American Spinal Injury Association (ASIA) score, the fracture level, Arbeitsgemeinschaft für Osteosynthesefragen (AO) classification, hospital stay, injury-to-operation interval, and associated injuries between the two groups. In addition, the prevertebral height ratio, the injured vertebra Cobb angle, and the injured vertebral endplate centre ratio were measured preoperatively, postoperatively, and at the final follow-up. Results: There were 63 patients (21 males and 42 females) with an average age of 44.7 years. Compared with group B, the injury vertebral endplate centre ratio significantly increased postoperatively and at the final follow-up (P<0.05) in group A. Conclusion: Short-segment posterior fixation with monoaxial or polyaxial pedicle screws via the fracture level for thoracolumbar fracture can achieve kyphosis correction, reduce sagittal alignment correction failure, and maintain anterior vertebral height. The insertion of monoaxial pedicle screws at the fracture level after thoracolumbar vertebral fracture has a flick up effect on the central vertebral body of the injured vertebrae, which is beneficial to the recovery of the vertebral endplate.

Objective To study the epidemiological correlation and drug resistance of external factors of infection caused by open injury of limbs to pathogens. Methods This experiment is a retrospective study. We took the geographical location and climate of Nanchang, Jiangxi Province, China as the background, analyzed 2017 strains of pathogens from 1589 patients with limb trauma infection in a University Affiliated Hospital from 2012 to 2017. Patients were divided into three groups according to the type of incision: I, In‐hospital infection of clean limb incision, II, In‐hospital infection with open injury, III, Community infection with open injury of the limb. Groups II and Groups III were divided into six subgroups according to the causes of trauma, including: accidents from non‐motor vehicles, machinery, cutting/piercing, pedestrian injuries, struck by/against, pedal cycles, and other injuries. We found eight common pathogens of orthopedic infection, which were mainly divided into Gram‐positive bacteria (G+, mainly including Staphylococcus ) and Gram‐negative bacteria (G‐, mainly Enterobacteriaceae ). The relationship between main pathogens and damage mechanism, apparent temperature and relative humidity was discussed in this study. SPSS v22.0 was used for statistical analysis of the data. Friedman's two‐way ANOVA was used to analyze the difference between the injury mechanism and incidence of pathogenic bacteria. Linear regression was used to determine the trend between the incidence of major pathogens and seasonal temperature and humidity. The level of significance was set as P < 0.05. Results There was no significant difference in the distribution of pathogens between Groups II and Groups III ( P >0.05). The drug resistance of Groups III was significantly higher than that of Groups II and Groups I. G+ bacteria were resistant to cephalosporin, ceftriaxone and other cephalosporins and erythromycin and other macrolides. They were sensitive to vancomycin and linezolid. G‐ were resistant to the first‐ and the second‐generation cephalosporins, including cefotetan and cefazolin, and ampicillin and other penicillins, while they were sensitive to third‐generation cephalosporins, such as ceftazidime, as well as to levofloxacin and other quinolones, meropenem, and other beta‐lactamases. The correlation between the injury mechanism and infection of pathogenic bacteria was not significant. The monthly average apparent temperature and relative humidity were correlated with the infection rate of pathogenic bacteria. Conclusion In open injury of extremities, apparent temperature and relative humidity is an important risk factor for infection by pathogenic bacteria and the drug resistance of pathogenic bacteria in out‐of‐hospital infection was lower than that of hospital infection.

Background To evaluate the efficacy and safety of percutaneous kyphoplasty (PKP) for thoracolumbar osteoporotic vertebral compression fracture (OVCF) with kyphosis via unilateral versus bilateral approach. Methods All patients suffered OVCF with kyphosis were retrospectively reviewed. Of those, performed unilateral PKP or underwent bilateral PKP with random. The clinical and radiological data such as the correction of deformity, sagittal profle and record of the perioperative morbidity of the patients were analyzed. Results All patients (76 ± 3.6 years) were enrolled in this investigation, including 41 in the unilateral and 45 in the bilateral group. No significant difference in general data was detected between the two groups (p > 0.05). Howere, the operation time and cement amount 28.2 ± 3.4 min, 3.8 ± 0.6 ml in the unilateral group, while 50.1 ± 4.6 min, 5.4 ± 0.5 ml in the bilateral group, respectively (P < 0.05).In addition,The preoperative visual analog scale(VAS) and Vertebral local kyphosis angle were 8.8 ± 0.65 and 16.3 ± 6.5°compared to last follow-up 3.15 ± 0.78 and 14.26 ± 2.16°in unilateral group, while 8.5 ± 0.78 and 16.5 ± 7.1°compared to last follow-up 2.66 ± 0.86 and 13.81 ± 2.38°in bilateral group, respectively (P < 0.05). Furthermore, Oswestry Disablility Index (ODI) and prevertebral height ratio in both groups were significantly different before and after surgery, but no significant difference between the two groups (p > 0.05). Conclusions Both bilateral and unilateral PKP are relatively safe and provide effective treatment for patients with painful thoracolumbar osteoporotic vertebral compression fracture with mild kyphotic deformity. However, unilateral PKP need less operation time and volume of cement.

OBJECTIVES To study the epidemiological correlation and drug resistance of external factors of infection caused by open injury of limbs to pathogens.METHODS We retrospective analyzed 2017 strains of pathogenic bacteria in a university hospital from 2012 to 2017.Patients were divided into three groups: I. In-hospital infection of clean limb incision, II. In-hospital infection with open injury, III. Community infection with open injury of the limb. We divided patients into six groups based on injury mechanism to explore the relationship between the main pathogens and damage mechanism, apparent temperature and relative humidity.RESULTS No significant difference was seen in the distribution of pathogens among the three groups. The drug resistance of group III was significantly lower than that of group II and group I. The correlation between the injury mechanism and infection of pathogenic bacteria was not significant. The monthly average apparent temperature and relative humidity were correlated with the infection rate of pathogenic bacteria.CONCLUSION In open injury of extremities, apparent temperature and relative humidity is an important risk factor for infection by pathogenic bacteria.The drug resistance of pathogenic bacteria in out-of-hospital infection was lower than that of hospital infection.

Objective: To evaluate the efficacy and safety of percutaneous kyphoplasty (PKP) for thoracolumbar osteoporotic vertebral compression fracture (OVCF) with kyphosis via unilateral versus bilateral approach.Methods: All patients suffered OVCF with kyphosis were retrospectively reviewed. Of those, performed unilateral PKP or underwent bilateral PKP with random. The clinical and radiological data such as the correction of deformity, sagittal profle and record of the perioperative morbidity of the patients were analyzed.Results: All patients (76±3.6 years) were enrolled in this investigation, including 47 in the unilateral and 39 in the bilateral group. No significant difference in general data was detected between the two groups (p >0.05). Howere, the operation time and cement amount 28.2±3.4 min, 3.8±0.6 ml in the unilateral group, while 50.1±4.6 min, 5.4±0.5 ml in the bilateral group, respectively (P <0.05).In addition,The preoperative visual analog scale(VAS) and Vertebral local kyphosis angle were 8.8±0.65 and 16.3 ± 6.5°compared to last follow-up 3.15±0.78 and 14.26± 2.16°in unilateral group, while 8.5±0.78 and 16.5 ± 7.1°compared to last follow-up 2.66±0.86 and 13.81±2.38°in bilateral group, respectively (P < 0.05). Furthermore, Oswestry Disablility Index (ODI) and prevertebral height ratio in both groups were significantly different before and after surgery, but no significant difference between the two groups (p >0.05).Conclusion: Both bilateral and unilateral PKP are relatively safe and provide effective treatment for patients with painful thoracolumbar osteoporotic vertebral compression fracture with mild kyphotic deformity. However, unilateral PKP need less operation time and volume of cement.

Objective To evaluate the efficacy of percutaneous kyphoplasty (PKP) for thoracolumbar osteoporotic vertebral compression fractures (OVCFs) via unilateral versus bilateral approach. Methods All patients who underwent PKP surgery for OVCFs in our hospital between June 2016 and December 2018 were included in this study. The pedicles were divided into two groups according to the manner of vertebral body puncture, which were as follows: unilateral pedicle puncture group (unilateral group, n=47) and bilateral pedicle puncture group (bilateral group, n=39).The operative time, amount of cement perfusion, correction angle of kyphosis, pain score before and after surgery, and leakage rate of bone cement were evaluated in all patients. The average follow-up was 19 months (range 13-34 months). Results The average age of patients who met the inclusion criteria, but not the exclusion criteria, was 76 years, and a total of 121 vertebral bodies were studied. There were 7 cases of postoperative bone cement leakage (unilateral group, 14.9%) and 6 cases of postoperative bone cement leakage (bilateral groups, 15.4%). There were differences in operative time and amount of cement perfusion between the two groups were statistically significant (P<0.05). There was no significant increase in age, body mass index, pain index during follow-up, treatment outcome, correction angle of kyphosis, and cement leakage rate between the two groups (P>0.05). Moreover, there was no significant difference in sex and bone cement leakage rate between the two groups by Pearson x 2 test (P>0.05). Conclusion Patients with OVCFs could obtain similar satisfactory clinical results via both unilateral and bilateral PKP approaches. However, the unilateral PKP approach is more advantageous as it has a shorter operative time, requires lesser cement volume, causes minimal trauma, is less costly, and results in lesser complications than the bilateral approach.