Incidences and reasons of postoperative surgical site infection after lumbar spinal surgery: a large population study.

PURPOSE: The purpose of this study was to determine the incidences of postoperative acute surgical site infection (SSI) after lumbar spinal surgery and its possible reasons in our hospital during the past 9 years. METHODS: This is a retrospective study with a large sample size. The medical records of all included patients were reviewed, and patients with acute SSI were identified. The incidence and possible reasons of SSI were determined. RESULTS: A total of 7240 patients who underwent posterior lumbar spinal surgery were included in this study, and the total incidence of postoperative SSI was 1.53% (111/7240). Gram-negative bacteria were found to be dominant in postoperative wound infections after lumbar spinal surgery. And Escherichia coli were the most common pathogen in patients with SSI. The rate of postoperative SSI following lumbar spinal surgery was increased at first and then decreased during the past 9 years. Additionally, from 2011 to 2014, it was mainly deep infection in these patients, and then was mainly superficial infection from 2015 to 2019. Patients with lumbar spinal stenosis had the highest incidence of postoperative SSI (2.39%, P < 0.001). There was also a significant difference for the number of SSI cases among different surgeons. CONCLUSION: Based on a large population analysis, Gram-negative bacteria were the most common pathogen in postoperative SSI after lumbar spinal surgery. And patients with lumbar spinal stenosis had the highest incidence of SSI. Increasing the intervention of Gram-negative may be an important step to reduce the postoperative SSI after lumbar spinal surgery.

Using the lamina nutrient foramen as the entry point for posterior cervical pedicle screw placement.

STUDY DESIGN: A prospective study and technique description. OBJECTIVE: This study introduced a method for posterior cervical pedicle screw placement by using the bilateral posterior lamina nutrient foramens as the entry point. METHODS: Firstly, 30 dry C3-C7 vertebrae specimens were harvested for measurement. The lamina nutrient foramens were used as the entry points for posterior cervical pedicle screw placement and four linear and two angle parameters were obtained from a computed tomography scan(CT). Then, 60 patients who underwent C3-C7 pedicle screw fixation using this method were included, linear and angle parameters were obtained from a postoperative CT. RESULTS: The average incidences of lamina nutrient foramen on the C3-C7 specimens were 88.3%, 90.0%, 95.0%, 95.0%, and 96.7%, respectively. The distances from the entry point to the pedicle screw tip (OD), the pedicle transverse angles (α), and the pedicle sagittal angles (ß) measure for the entry points from C3-C7 were 28.74 ± 3.45-30.15 ± 2.01 mm, 26.88 ± 6.89° to 32.72 ± 5.91°, and 12.48 ± 9.31° to 19.71 ± 8.45°, respectively, with no significant differences between the left and right sides. In the 60 patients who underwent surgery, the lengths of the pedicle screws (PL) were 28.34 ± 2.25-30.15 ± 2.31 mm, the pedicle transverse angles (α) were 26.89 ± 6.86° to 32.36 ± 5.65°, and the pedicle sagittal angles (ß) were 12.49 ± 9.11° to 20.06 ± 8.91°. The new method had a 96.8% (454/469) success rate among these patients, with no screws penetrating the spinal canal or signs of vertebral artery injury. CONCLUSION: Entry at the bilateral lamina nutrient foramen represents an alternative posterior cervical pedicle screw placement technique that is feasible and safe.

iTRAQ-based proteomic analysis of the molecular mechanisms and downstream effects of fatty acid synthase in osteosarcoma cells.

BACKGROUND: Fatty acid synthase (FASN) is a lipogenic enzyme that participates in tumor progression. We previously showed that FASN is dysregulated in OS malignancy, but the molecular mechanism(s) of these effects remained unclear. METHODS: We examined differentially expressed proteins (DEPs) in FASN-silenced osteosarcoma 143B cells and their parental cells by isobaric tags for relative and absolute quantitation (iTRAQ). Differentially expressed proteins were classified using GO and KEGG analysis. The association between FASN and heterogeneous nuclear ribonucleoprotein A1 (HNRNPA1) was confirmed using qPCR, Western blot, and immunohistochemistry. The function of HNRNPA1 in osteosarcoma was determined using CCK-8, colony formation, wound healing, transwell migration, and invasion assays. RESULTS: Among the 4971 identified proteins, 567 DEPs (325 upregulated and 242 downregulated) were identified. The top 10 upregulated proteins comprised HIST1H2AB, INA, INTS5, MTCH2, EIF1, MAPK1IP1L, PXK, RPS27, PM20D2, and ZNF800, while the top 10 downregulated proteins comprised NDRG1, CNTLN, STON2, GDF7, HECTD3, HBB, TPM1, PPP4R4, PTTG1IP, and PLCB3. Bioinformatic analysis indicated that the DEPs were related to cellular processes, metabolic processes, biological regulation, binding, and catalytic activity. HNRNPA1 was dysregulated in FASN-silenced 143B and HOS cells. qPCR, Western blot, and immunohistochemistry showed that FASN expression positively correlates with HNRNPA1 expression. Further studies indicated that HNRNPA1 correlates with OS diagnosis and prognosis. And HNRNPA1 silence inhibits the proliferation, migration, and invasion in OS cells. CONCLUSION: HNRNPA1 acts as targets downstream of FASN and potential biomarker and oncogene in OS.

Diagnostic value of CA-153 and CYFRA 21-1 in predicting intraocular metastasis in patients with metastatic lung cancer.

Lung cancer is prone to metastasis to various organs. Although intraocular metastasis (IOM) occurs at a later stage than metastasis to other organs, it often adversely affects the quality of life and suggests a poor prognosis. In this study, we selected 1608 patients with lung cancer who had metastasis to at least one site and explored clinical differences between those with IOM and non-IOM (NIOM). An independent t test and chi-squared test were used to analyze the clinical features of the patients. The statistically significant parameters were analyzed by binary logistic regression to determine the risk factors for IOM. A receiver operating characteristic curve was constructed to assess their diagnostic value in IOM. The results showed that no significant differences were noted in age, gender, and pathological type between the IOM and NIOM groups. However, the IOM group had higher levels of alpha-fetoprotein, carcinoembryonic antigen, cancer antigen (CA)-125, CA-153, cytokeratin fragment 19 (CYFRA 21-1), and total prostate-specific antigen, compared with the NIOM group. Binary logistic regression indicated that CA-153 and CYFRA 21-1 were risk factors for IOM in patients with MLC (P < 0.05). Area under the curve of CA-153, CYFRA 21-1 and their combination were 0.791, 0.860, and 0.872 respectively. The cutoff values for CA-153 and CYFRA 21-1 were 22.2 U/mL and 6.785 ng/mL. In conclusion, both CA-153 and CYFRA 21-1 were independent risk factors for IOM in patients with metastatic lung cancer (MLC), whereas the combination of CA-153 and CYFRA 21-1 assessment yields the most value in the detection of IOM in patients with MLC.

LHX2 promotes malignancy and inhibits autophagy via mTOR in osteosarcoma and is negatively regulated by miR-129-5p.

The transcript factor LHX2 is dysregulated in many cancers but its role in osteosarcoma (OS) remains unclear. In this study, we confirm that LHX2 is up-regulated in osteosarcoma, and that its silencing inhibits OS malignancy and induces autophagy via mTOR signaling. We further demonstrate that miR-129-5p negatively regulates LHX2 and suppresses the malignant phenotypes of OS. LHX2 overexpression could restore the malignant phenotypes. In conclusion, LHX2 regulates tumorigenesis and autophagy via mTOR in OS and is negatively regulated by miR-129-5p. Targeting the miR-129-5p/LHX2/mTOR axis therefore represents a novel therapeutic strategy for OS treatment.

SM­164 enhances the antitumor activity of adriamycin in human U2­OS cells via downregulation of X­linked inhibitor of apoptosis protein.

The antitumor effects of SM­164 and adriamycin (ADM) on human osteosarcoma U2­OS cells, the underlying mechanism are yet to be investigated. In the present study, U2­OS cells were divided into control, ADM, SM­164, and ADM + SM­164 groups. In addition, cells treated with both SM­164 and ADM were further divided into three subgroups: SM­164 + ADM, SM­164 + ADM + vector and SM­164 + ADM + X­linked inhibitor of apoptosis protein (XIAP) silencing groups. XIAP expression was achieved via transfection with shRNA lentiviral vectors. Reverse transcription­quantitative polymerase chain reaction and western blotting were used to detect the expression of caspases­7, ­9, and ­3, poly ADP­ribose polymerase (PARP), XIAP, cellular inhibitor of apoptosis protein­1 (cIAP­1) and survivin. Cell viability and apoptosis were evaluated using MTT and flow cytometry assays, respectively. Compared with the control group, cell viability decreased, while apoptosis was increased in the ADM and SM­164­treatment group. ADM and SM­164 treatment promoted the expression of caspases­7, ­9 and ­3, and PARP, but reduced the expression of XIAP, survivin and cIAP­1. Compared with ADM + SM­164 group, XIAP silencing with ADM + SM­164 treatment further reduced cell viability, promoted apoptosis, increased caspase­7, ­9 and ­3, and PARP expression; however the expression of survivin and cIAP­1 were reduced. Combined ADM and SM­164 treatment may be considered as potential therapeutic agent in the treatment of osteosarcoma, possibly via reductions XIAP expression.

The Value of MR Imaging in Comparative Analysis of Spinal Infection in Adults: Pyogenic Versus Tuberculous.

OBJECTIVE: Differentiating pyogenic spondylitis (PS) and tuberculous spondylitis (TS) is challenging but critical in clinical practice. Accurate diagnosis and early treatment are crucial to preventing further progression of disease. Magnetic resonance imaging (MRI) is considered the best method for the diagnosis of spinal infection, but results remain imprecise; therefore, by comparing and analyzing the MRI findings of spinal infections, we intend to identify key distinguishing features between PS and TS, and with that establish a systematic scoring method to help clinicians. METHODS: The MRI features of 70 cases of spinal infection (32 cases of PS, 38 cases of TS), confirmed by pathology or clinical diagnosis, were retrospectively analyzed. The receiver operating characteristic curve was used to analyze the diagnostic efficacy of the MRI parameter scores in PS and TS. RESULTS: Among the 70 cases, the average age was 54.5 years, and 43 were male. Sixteen parameters were significantly different between the PS and TS groups. We hypothesized that a diagnosis of PS could be made when the number of parameters characteristic of PS exceeded the number of parameters characteristic of TS, and vice versa. We randomly selected 70% (49 patients) of the 70 patients for analysis, and then validated in the remaining 30% (21 patients) of cases. Using 0.5 as the cutoff value, of the remaining 21 patients, the correct coincidence rate was 95.23%, sensitivity was 91.67%, specificity was 100%, false-positive rate was 0%, and false-negative rate was 8.3%. The MRI parameter scores of PS and TS were analyzed with the receiver operating characteristic; area under the curve was 1.00. CONCLUSIONS: Our systematic scoring system of MRI parameters is helpful in differentiating PS and TS.

Risk Factors for Surgical Site Infection After Posterior Lumbar Spinal Surgery.

STUDY DESIGN: A retrospective study. OBJECTIVE: The purpose of this study was to identify the independent risk factors for postoperative surgical site infection (SSI) after posterior lumbar spinal surgery based on the perioperative factors analysis. SUMMARY OF BACKGROUND DATA: SSI is one of the most common complications after spinal surgery. Previous studies have identified different risk factors for postoperative SSI after lumbar spinal surgery. However, most of the studies were focused on the patient and procedure-related factors. Few studies reported the correlation between laboratory tests and postoperative SSI. METHODS: A retrospective study was carried out in a single institution. Patients who underwent posterior lumbar spinal surgery between January 2010 and August 2016 were included in this study. All patients' medical records were reviewed and patients with postoperative SSI were identified. Perioperative variables were included to determine the risk factors for SSI by univariate and multivariate regression analysis. RESULTS: A total of 2715 patients undergoing posterior lumbar spinal surgery were included in this study. Of these patients, 64 (2.4%) were detected with postoperative SSI, including 46 men and 18 women. Diabetes mellitus (P = 0.026), low preoperative serum level of calcium (P = 0.009), low preoperative and postoperative albumin (P = 0.025 and 0.035), high preoperative serum glucose (P = 0.029), multiple fusion segments (P < 0.001), increased surgical time and estimated blood loss (P = 0.023 and 0.005), decreased postoperative hemoglobin (P = 0.008), and prolonged drainage duration (P = 0.016) were found to be the independent risk factors for SSI. Multilevel fusion and a history of diabetes mellitus were the two strongest risk factors (odds ratio = 2.329 and 2.227) for SSI. CONCLUSION: Based on a large population analysis, previous reported risk factors for SSI were confirmed in this study while some new independent risk factors were identified significantly associated with SSI following lumbar spinal surgery, including preoperative low serum level of calcium, decreased preoperative and postoperative albumin, and decreased postoperative hemoglobin. LEVEL OF EVIDENCE: 4.

Risk factors for bone metastasis from renal cell cancer.

OBJECTIVE: The prognosis for renal cell carcinoma (RCC) is related to a high rate of metastasis, including 30% of bone metastasis. In this study, we investigate the correlation between diverse clinical factors and bone metastases secondary from renal cell cancer (RCC), and to identify potential risk factors for bone metastasis in newly diagnosed patients and those who have already received treatment. METHODS: The clinical data of 372 patients with RCC were reviewed from January 2000 to August 2016. The correlations between age, gender, histopathologic types, alkaline phosphotase (ALP), CEA, AFP, CA-125, CA-153, CA-199, calcium, hemoglobin (HB) and bone metastases were analyzed. And the risk factors for bone metastases in RCC were identified by multivariate logistic regression analysis. The cutoff value, sensitivity and specificity of the independent correlation factors were calculated by receiver operating characteristic (ROC) curve. RESULTS: The bone is the second to the lung as a distant metastasis target site in patients with RCC. Thirty eight individuals were identified with bone metastases. Of these patients, significantly higher levels of ALP, calcium, HB were found than those without bone metastasis (P < 0.05, respectively). No significant differences were detected in CEA, AFP, CA-125, CA-153, CA-199, age, gender and histopathologic types between patients with and without bone metastases (P > 0.05, respectively). Multivariate logistic regression analysis indicated that ALP, calcium and HB were independent risk factors correlated with bone metastasis (P < 0.05, respectively). ROC curves demonstrated these factors had comparable accuracy at predicting bone metastasis (AUC were 0.749, 0.633 and 0.665, respectively). The cutoff values of ALP, calcium and HB were 105.5 U/L, 2.615 mmol/L and 111.5 g/L, respectively. The sensitivities of them were 57.9%, 36.8% and 71.1% for predicting bone metastasis, with specificities of 83.5%, 95.2% and 65.3%, respectively. CONCLUSION: Based on our study, the concentrations of ALP, calcium and HB were potentially risk factors for bone metastasis in patients with RCC. For newly diagnosed patients, if the values of ALP>105.5 U/L, calcium>2.615 mmol/L and HB<111.5 g/L were detected, intensive monitoring and bone scanning are warranted for them.

Clinical characteristics and risk factors for developing bone metastases in patients with breast cancer.

The risk factors for predicting bone metastases in patients with breast cancer are still controversial. Here, a total of 2133 patients with breast cancer, including 327 with bone metastases (15.33%) and 1806 without bone metastases (84.67%) were retrospective reviewed from January 2005 to December 2015. The spine was found to be the most common site for bone metastases, followed by ribs (57.5%), pelvis (54.1%) and sternum (44.3%). The results indicated that axillary lymph node metastases and the concentrations of CA125, CA153, ALP and hemoglobin were the independent risk factors for bone metastases in patients with breast cancer. The receiver operating characteristics (ROC) curves showed that combined axillary lymph node metastases, high CA153 and ALP, with low hemoglobin were the most accurate biomarkers for predicting bone metastases in breast cancer [area under the curve = 0.900], and the sensitivity and specificity for the prediction were 78.5% and 87.8%, respectively. Therefore, breast cancer patients with more axillary lymph node metastases, high serum concentrations of CA125, CA153, ALP and low level of hemoglobin were closely related to bone metastases. Combined axillary lymph node metastases, CA153, ALP with hemoglobin have the highest predictive accuracy for bone metastases in breast cancer.

Incidence and risk factors for symptomatic spinal epidural haematoma following lumbar spinal surgery.

PURPOSE: Spinal epidural haematoma (SEH) is a common complication after lumbar spinal decompression surgery, and symptomatic SEH usually causes devastating neurological deficits. Although different risk factors for post-operative SEH have been reported, few studies focused on patients' laboratory tests. The purpose of this study was to analyze the incidence of symptomatic SEH following lumbar spinal surgery, as well as identify the risk factors for it. METHODS: Patients who underwent posterior lumbar spinal decompression surgery between January 2010 and August 2016 were included in this study and their medical records were retrospectively reviewed. Those who developed post-operative symptomatic SEH after the surgery were identified. The risk factors for SEH were analyzed by univariate and multivariate regression analysis. RESULTS: In total, 2715 patients were included in this study and 31 (1.14%) were identified with post-operative symptomatic SEH. Of these patients, 19 were males and 12 were females, with an average age of 59.39 ± 11.66 years. After multivariate logistic regression analysis, low serum calcium level (P = 0.025), blood type A (P = 0.04), increased estimated blood loss (P = 0.032), prolonged surgical duration (P = 0.018), and decreased post-operative globulin (P = 0.016) were identified as the independent risk factors for post-operative SEH following lumbar spinal surgery. Furthermore, prolonged surgical duration (odds ratio = 3.105) was the strongest risk factor for SEH. CONCLUSION: Based on a large population investigation, the incidence of symptomatic SEH following lumbar spinal decompression surgery was 1.14%. Blood type A, increased estimated blood loss, and prolonged surgical duration were identified as the independent risk factors for post-operative SEH while two new risk factors, including low serum calcium level and decreased post-operative globulin, were firstly identified in this study.

Serum Concentrations of Fibrinogen in Patients with Spinal Cord Injury and Its Relationship with Neurologic Function.

BACKGROUND: Many studies have focused on axon regeneration after spinal cord injury (SCI), and fibrinogen has been reported to be an inhibitory factor for axon regeneration. However, most of these studies were based on animal experiments and in vitro trials. Few studies reported serum concentrations of fibrinogen in patients with SCI. OBJECTIVE: We sought to investigate the circulating serum concentrations of fibrinogen in patients with SCI and determine the relationship between fibrinogen concentrations and patients' neurologic function. METHODS: A total of 306 patients who were diagnosed with acute SCI between January 2008 and March 2016 were included in this study. Patients with traumatic fractures of the extremities at the same period (220 of them with single fracture and 207 with multiple fractures) were enrolled as a control group. Additionally, 151 patients with no injury were involved as the normal group. The fibrinogen concentrations in each group were recorded and compared at different time points, and the correlation between fibrinogen serum concentrations and American Spinal Injury Association impairment scale in patients with SCI were analyzed. RESULTS: The mean serum concentrations of fibrinogen within 2 days after injury were 2.63 ± 0.76 g/L in the SCI group, 3.03 ± 0.82 g/L in the single-fracture group, and 2.86 ± 0.91 g/L in the multiple-fractures group, respectively, which were significant higher than those in the normal group (2.33 ± 0.43 g/L). Additionally, the concentrations of fibrinogen in SCI group were significantly lower compared with those in single- and multiple-fractures groups (P < 0.001 and P = 0.001). The positive rate of fibrinogen concentrations was 12.42% in the SCI group, which was significantly lower than that of the single-fracture group (25.45%) and multiple-fractures group (25.13%) (P < 0.01). In patients with SCI, Spearman correlation analysis revealed that a significant correlation was found between fibrinogen serum concentrations and patients' American Spinal Injury Association impairment scales (r = 0.17, P < 0.001). CONCLUSIONS: The serum concentrations of fibrinogen in patients with SCI were significantly increased after injury and were correlated with the severity of neurologic deficit in patients with SCI.

Radiographic Evaluation of the Reliability of Neck Anatomic Structures as Anterior Cervical Surgical Landmarks.

BACKGROUND: Accurate location of the skin incision is helpful to decrease the technical difficulty and save the operative time in anterior cervical spine surgery. Spine surgeons usually use the traditional neck anatomic structures (the hyoid bone, thyroid cartilage, and cricoid cartilage) as landmarks during the surgery. However, the reliability of these landmarks has not been validated in actual practice. OBJECTIVE: To find out which landmark is the most accurate for identifying the cervical levels in anterior cervical spine surgery. METHODS: The lateral flexion and extension radiographs of cervical spine in standing position from 30 consecutive patients from January 2015 to February 2015 were obtained. The cervical vertebral bodies from C2 to C7 were divided equally into 2 segments. The cervical segments corresponding to each of the surface landmarks were recorded on the flexion and extension radiographs, respectively, and the displacement of corresponding cervical segments from the flexion to extension radiographs for each landmark was calculated. RESULTS: Based on the measurements, the main corresponding cervical levels for the mandibular angle were C2 on both of the flexion and extension films, for the hyoid bone were the C3-C4 interspace on flexion film and C3 on extension film, for the thyroid cartilage C5 on both of flexion and extension films, and for the cricoid cartilage C6 on flexion film and C5-C6 interspace on extension film, respectively. The ratios of displacement within 2 segments from flexion to extension were 83.3% (25/30) for mandibular angle, 56.7% (17/30) for hyoid bone, 66.7% (20/30) for thyroid cartilage, and 56.7% (17/30) for cricoid cartilage, respectively. The mean displacement from flexion to extension films were significantly less than 2 cervical segments for the mandibular angle but greater than 2 segments for the other landmarks. Significant differences were found between mandibular angle and the other 3 landmarks for the displacement from flexion to extension. CONCLUSIONS: The angle of mandible was found to be the most accurate landmark for identifying the cervical level, which corresponded to C2 and C2-C3 disc space. The hyoid bone, thyroid cartilage, and cricoid cartilage were not reliable to predict the cervical levels.

The incidences and risk factors related to early dysphagia after anterior cervical spine surgery: A prospective study.

Dysphagia is a common complication following anterior cervical spine surgery (ACSS). The incidences of dysphagia were variable and controversial. The purpose of this study was to determine the incidence of early dysphagia after ACSS with a new scoring system, and to identify the risk factors of it. A prospective study was carried out and patients who underwent ACSS from March 2014 to August 2014 in our hospital were included in this study. A self-designed dysphagia questionnaire was delivered to all of the patients from the first day to the fifth day after ACSS. Perioperative characteristics of patients were recorded, and incidences and risk factors of dysphagia were analyzed. A total of 104 patients who underwent ACSS were included and incidences of dysphagia from the first to the fifth day after ACSS was 87.5%, 79.81%, 62.14%, 50% and 44.23%, respectively. There was a good correlation between the new dysphagia scoring system and Bazaz scoring system (P < 0.001). Operative time and body mass index (BMI) were the risk factors for dysphagia during the first to the second day postoperatively. However, the dC2-C7angle was the main risk factor for dysphagia from the third to the fifth day after surgery. There were comparatively high incidences of early dysphagia after ACSS, which may be ascribed to operative time, BMI and the dC2-C7 angle.

AMD3100 inhibits the migration and differentiation of neural stem cells after spinal cord injury.

It was reported that CXCR4 signaling played an important role in the migration and differentiation of endogenous neural stem cells after spinal cord injury (SCI). However, the molecular mechanism of it is still unclear. Here, we established a model of SCI in rats and AMD3100 was used to treat them. The rats were then sacrificed and the injured spinal cord specimens were harvested. Additionally, the neural stem cells (NSCs) line was culture and treated with AMD3100 in vitro. Results showed the locomotor function of SCI rats was worse after treated with AMD3100. And the expression levels of Nestion in neural stem cells and ß-tubulin in neuron cells were significantly increased in the injured spinal cord, which can be inhibited by the CXCR4 antagonist of AMD3100. Additionally, the expression of ß-catenin and phosphorylase ß-catenin protein was significantly down regulated by AMD3100. In vitro, the NSCs proliferation ability was inhibited and the migration was decreased after treated with AMD3100. Also, the expression of Nestion, ß-tubulin, ß-catenin and phosphorylase ß-catenin protein was significantly decreased in AMD3100 group comparing with untreated group. Taken together, this study suggested that AMD3100 could inhibit the migration and differentiation of endogenous neural stem cells in rats with SCI. The mechanism of it maybe that AMD3100 could down regulate of SDF-1/CXCR4 by targeting ß-catenin signaling pathway.

A comparison of local bone graft with PEEK cage versus iliac bone graft used in anterior cervical discectomy and fusion.

OBJECTIVE: Anterior cervical discectomy and fusion (ACDF) is a popular procedure for patients with cervical spondylotic myelopathy, but few studies reported the clinical outcomes of cervical local bone graft with a PEEK cage used in it. This retrospective study was performed to compare the clinical and radiological outcomes of using local bone graft with a PEEK cage versus iliac bone graft in ACDF. PATIENTS AND METHODS: A total of 60 consecutive patients who underwent ACDF were evaluated from January 2010 to January 2013. Twenty-nine patients received ACDF with a PEEK cage combined with cervical local bone graft (local bone group) and 31 patients received ACDF with autologous tricortical iliac bone graft (iliac bone group). The intraoperative and perioperative complications of both groups were recorded. Preoperative and postoperative radiographs were taken to calculate the ratio of interbody height to the disc height and the interbody bony fusion rate. The Japanese Orthopedic Association (JOA) score and visual analogue scale (VAS) were used to estimate postoperative clinical outcomes. RESULTS: The mean follow-up duration was 25.0±3.8months in the local bone group and 24.4±3.4months in the iliac bone group (P=0.56). Although there was no significant difference between the two groups in terms of blood loss (P=0.17), the length of surgery was significantly less in the local bone group comparing with that of iliac bone group (P=0.01). Postoperatively, VAS scores were significantly decreased, and JOA scores were improved in both groups. However, no statistically significant differences were found between the two groups at final follow up (P=0.45 and P=0.93). The disc space height and segmental interbody angle at the surgical segment were greater in local bone group than those in the iliac bone group (P<0.001 and P<0.001). The fusion rates were 93.1% in local bone group and 90.3% in the iliac bone group at last follow up (P=0.70). Perioperative complication rates in local bone group and iliac bone groups were 6.8% and 29%, respectively (P=0.04). CONCLUSIONS: Based on this study, patients receiving ACDF with local bone graft combined with a PEEK cage had significant shorter operation time, lower perioperative complications rate, and better radiological results comparing with those with an iliac bone graft alone. It seems that the local bone graft with a PEEK cage appears to be a safe alternative to the iliac bone graft for ACDF.

The effect of screw tunnels on the biomechanical stability of vertebral body after pedicle screws removal: a finite element analysis.

PURPOSE: Posterior reduction and pedicle screw fixation is a widely used procedure for thoracic and lumbar vertebrae fractures. Usually, the pedicle screws would be removed after the fracture healing and screw tunnels would be left. The aim of this study is to evaluate the effect of screw tunnels on the biomechanical stability of the lumbar vertebral body after pedicle screws removal by finite element analysis (FEA). METHODS: First, the CT values of the screw tunnels wall in the fractured vertebral bodies were measured in patients whose pedicle screws were removed, and they were then compared with the values of vertebral cortical bone. Second, an adult patient was included and the CT images of the lumbar spine were harvested. Three dimensional finite element models of the L1 vertebra with unilateral or bilateral screw tunnels were created based on the CT images. Different compressive loads were vertically acted on the models. The maximum loads which the models sustained and the distribution of the force in the different parts of the models were recorded and compared with each other. RESULTS: The CT values of the tunnels wall and vertebral cortical bone were 387.126±62.342 and 399.204±53.612, which were not statistically different (P=0.149). The models of three dimensional tetrahedral mesh finite element of normal lumbar 1 vertebra were established with good geometric similarity and realistic appearance. After given the compressive loads, the cortical bone was the first one to reach its ultimate stress. The maximum loads which the bilateral screw tunnels model, unilateral screw tunnel model, and normal vertebral model can sustain were 3.97 Mpa, 3.83 Mpa, and 3.78 Mpa, respectively. For the diameter of the screw tunnels, the model with a diameter of 6.5 mm could sustain the largest load. In addition, the stress distributing on the outside of the cortical bone gradually decreased as the thickness of the tunnel wall increased. CONCLUSIONS: Based on the FEA, pedicle screw tunnels would not decrease the biomechanical stability and strength of the vertebral body. A large diameter of screw tunnel and thick tunnel wall were helpful for the biomechanical stability of the vertebral body.

One-stage posterior surgical management of lumbosacral spinal tuberculosis with nonstructural autograft.

OBJECTIVE: Lumbosacral spinal tuberculosis is rare in current population. Previous studies have reported effective outcomes about anterior, antero-posterior and posterior surgery for treating tuberculosis of lumbosacral region. However, the bone grafts used in these studies are mainly structural bone and mesh cage. The purpose of this study is to evaluate the efficacy and safety of nonstructural autograft in the surgical treatment of lumbosacral tuberculosis by one-stage posterior procedure. PATIENTS AND METHODS: A total of 21 patients with lumbosacral tuberculosis were retrospectively reviewed between January 2012 and December 2014. All the patients underwent one-stage posterior debridement, interbody fusion with nonstructural autograft and posterior instrumentation. The preoperative and postoperative erythrocyte sedimentation rates (ESR), C-reactive protein (CRP) and visual analogue scale (VAS) were recorded. Preoperative and postoperative lumbosacral angle and intervertebral space height were measured on the plain films. American Spinal Injury Association (ASIA) Impairment Scale was used to evaluate the neurological outcomes of the patients. RESULTS: The average follow up period was 22.9±6.7months (range 12-36 months). The preoperative ESR and CRP were 33.4±10.5mm/h and 30.3±20.3mg/l, respectively, which decreased to 15.2±7.1mm/h and 10.6±5.8mg/l postoperatively with significant differences (P<0.05). The lumbosacral angles and intervertebral space height were increased from preoperative 20.4°±4.5° and 9.7±1.9mm to postoperative 25.6°±4.6° and 12.3±2.1mm, respectively (P<0.001 and P<0.001). At the final follow up, a loss of 2.1°of lumbosacral angles and 1.6mm of intervertebral space height was observed. The VAS scores were decreased from 4.73 to 2.71. Bony fusion was achieved in all patients at 6 months after surgery. Neurological outcomes were improved with 1-2 grades in most of the patients. One patient got wound infection and was cured by daily dressing. Complications related to instrumentation or neurological deficit weren't observed. CONCLUSION: Combined with one-stage posterior debridement and instrumentation, interbody fusion with nonstructural autograft is an effective option for lumbosacral tuberculosis.

Is nonstructural bone graft useful in surgical treatment of lumbar spinal tuberculosis?: A retrospective case-control study.

Surgical intervention is an important option for treating spinal tuberculosis. Previous studies have reported different surgical procedures and bone grafts for it. To our knowledge, few studies demonstrated the clinical results of using nonstructural autogenous bone graft in surgical treatment of spinal tuberculosis.The purpose of this study is to compare the clinical outcomes of surgical management lumbar spinal tuberculosis by one-stage posterior debridement with nonstructural autogenous bone grafting and instrumentation versus anterior debridement, strut bone grafting combined with posterior instrumentation.A total of 58 consecutive patients who underwent surgical treatment due to lumbar spinal tuberculosis from January 2011 to December 2013 were included. A total of 22 patients underwent one-stage posterior debridement, nonstructural autogenous bone grafting, and instrumentation (group A), and 36 patients received anterior debridement, strut bone grafting combined with posterior instrumentation (group B). The operative duration, total blood loss, perioperative transfusion, length of hospital stay, hospitalization cost, and complications were recorded. The bony fusion of the graft was assessed by computed tomography scans. American Spinal Injury Association (ASIA) Impairment Scale was used to evaluate the neurological function of patients in the 2 groups.All the patients were followed up, with a mean follow-up duration of 21.6 ±â€Š5.7 months in group A and 22.3 ±â€Š6.2 months in group B (P = 0.47). The average operative duration was 257.5 ±â€Š91.1 minutes in group A and 335.7 ±â€Š91.0 minutes in group B (P = 0.002). The mean total blood loss was 769.6 ±â€Š150.9 mL in group A and 1048.6 ±â€Š556.9 mL in group B (P = 0.007). Also, significant differences were found between the 2 groups in perioperative transfusion volumes, length of hospital stay, and hospitalization cost (P < 0.05), which were less in group A compared with group B. Patients with ASIA grade C/D in the 2 groups were improved with 1 to 2 grades after the surgery with no statistical difference (P = 1.000). The perioperative complications rate was 9.1% (2/22) in group A and 13.9% (5/36) in group B (P = 0.897).Based on a retrospective study, the procedure of one-stage posterior debridement, nonstructural autogenous bone grafting, and instrumentation has a significant shorter operative duration, lower blood loss and perioperative transfusion, shorter hospital stay, and less hospitalization cost compared with the one of anterior debridement, strut bone grafting combined with posterior instrumentation for treating lumber spinal tuberculosis.

A comparative study of perioperative complications between transforaminal versus posterior lumbar interbody fusion in degenerative lumbar spondylolisthesis.

BACKGROUND: Both posterior lumbar interbody fusion (PLIF) and transforaminal lumbar interbody fusion (TLIF) are accepted surgical techniques for the treatment of degenerative lumbar spondylolisthesis (DLS). However, it is still unclear one technique offers distinct advantages over the other. OBJECTIVE: A retrospective study was performed to compare perioperative complications and functional outcomes of patients undergoing TLIF versus PLIF for DLS. METHODS: A total of 226 consecutive patients who underwent surgery for treatment of DLS at three institutions were evaluated from January 2012 to December 2014. In this series, 125 patients underwent PLIF and 101 received TLIF. The operative time, blood loss, allogeneic blood transfusion rate and perioperative complications (including re-operative rate, nerve root injury, dural tear, wound infection) were compared between the two groups. Pain (VAS) and functional outcomes of patients (Kirkaldy-Willis criteria) were quantified before surgery and 1 week after surgery. RESULTS: Patients involved in the two groups had similar baseline demographic, clinical and radiographic characteristics. The PLIF group was associated with a higher incidence of post-operative iatrogenic nerve root dysfunction [12 cases (9.6 %) versus 2 cases (1.9 %), P = 0.018] and dural tears [15 cases (12 %) versus 4 cases (3.9 %), P = 0.030]. The re-operation rate was significantly higher in patients undergoing PLIF [13 cases (10.4 %) versus 2 cases (1.9 %), P = 0.011]. In addition, intra-operative blood loss, operative times, and allogeneic blood transfusion rates were higher in the PLIF group when compared to the TLIF group (P < 0.05). The wound infection rate of the PLIF group was similar to that of the TLIF group (7.2 versus 5.0 %, P = 0.486). VAS scores were decreased from 7.08 ± 1.13 to 2.84 ± 0.89 in the PLIF group, and from 7.18 ± 1.09 to 2.84 ± 0.91 in the TLIF group, respectively (P = 0.32). 85.6 % of patients in the TLIF group had good or excellent functional outcomes within the first post-operative week compared to 83.2 % in the PLIF group (P = 0.64). CONCLUSION: Both PLIF and TLIF were equally beneficial in improving short-term functional outcomes for patients with DLS. However, PLIFs were associated with statistically significant higher incidences of nerve root injury, dural tears, allogeneic blood transfusion, increased intra-operative times, blood loss and re-operations. Therefore, caution should be exercised when considering PLIFs.