Comparison of Accuracy and Clinical Outcomes of Robot-Assisted Versus Fluoroscopy-Guided Pedicle Screw Placement in Posterior Cervical Surgery.

STUDY DESIGN: This was a prospective controlled study. OBJECTIVE: To compare the accuracy and clinical outcomes of robot-assisted (RA) and fluoroscopy-guided (FG) pedicle screw placement in posterior cervical surgery. METHODS: This study included 58 patients. The primary outcome measures were the 1-time success rate and the accuracy of pedicle screw placement according to the Gertzbein-Robbins scales. The secondary outcome measures, including the operative time, intraoperative blood loss, hospital stay, cumulative radiation time, radiation dose, intraoperative advent events, and postoperative complications, were recorded and analyzed. The Japanese Orthopedics Association (JOA) scores and Neck Disability Index (NDI) were used to assess the neurological function of patients before and at 3 and 6 months after surgery. RESULTS: The rate of grade A was significantly higher in the RA group than in the FG group (90.6% and 71.1%; P < .001). The clinically acceptable accuracy was 97.2% in the RA group and 90.7% in the FG group (P = .009). Moreover, the 1-time success rate was significantly higher in the RA group than in the FG group. The RA group had less radiation time (P < .001) and less radiation dose (P = .002) but longer operative time (P = .001). There were no significant differences in terms of intraoperative blood loss, hospital stay, intraoperative adverse events, postoperative complications, JOA scores, and NDI scores at each follow-up time point between the 2 groups. CONCLUSIONS: The RA technique achieved higher accuracy and 1-time success rate of pedicle screw placement in posterior cervical surgery while achieving comparable clinical outcomes.

Leptin regulates disc cartilage endplate degeneration and ossification through activation of the MAPK-ERK signalling pathway in vivo and in vitro.

Recent findings demonstrate that leptin plays a significant role in chondrocyte and osteoblast differentiation. However, the mechanisms by which leptin acts on cartilage endplate (CEP) cells to give rise to calcification are still unclear. The aim of this study was to evaluate the effects of leptin that induced mineralization of CEP cells in vitro and in vivo. We constructed a rat model of lumbar disc degeneration and determined that leptin was highly expressed in the presence of CEP calcification. Rat CEP cells treated with or without leptin were used for in vitro analysis using RT-PCR and Western blotting to examine the expression of osteocalcin (OCN) and runt-related transcription factor 2 (Runx2). Both OCN and Runx2 expression levels were significantly increased in a dose- and time-dependent manner. Leptin activated ERK1/2 and STAT3 phosphorylation in a time-dependent manner. Inhibition of phosphorylated ERK1/2 using targeted siRNA suppressed leptin-induced OCN and Runx2 expression and blocked the formation of mineralized nodules in CEP cells. We further demonstrated that exogenous leptin induced matrix mineralization of CEP cells in vivo. We suggest that leptin promotes the osteoblastic differentiation of CEP cells via the MAPK/ERK signal transduction pathway and may be used to investigate the mechanisms of disc degeneration.

Single transverse-orientation cage via MIS-TLIF approach for the treatment of degenerative lumbar disease: a technical note.

BACKGROUND: Single transverse cage placed in the anterior vertebral column can better maintain lumbar lordosis and sagittal alignment and is frequently used via the lateral transpsoas approach. However, there is no clear description in the literature of the steps required to place the single transverse cage during the instrumented transforaminal lumbar interbody fusion (TLIF) procedure for the treatment of degenerative lumbar disease. The objective of this study is to describe the technique using single transverse-orientation cage when performing TLIF procedures. MATERIALS AND METHODS: We present 18 illustrative cases in which single transverse-orientation cage was placed according to a step-by-step technique that can be used during the TLIF procedure. Information acquired included procedure time, intraoperative blood loss and postoperative complications. The preoperative and postoperative Oswestry Disability Index (ODI) and the visual analogue scale (VAS) scores were recorded. Changes in disc height and segmental lordosis were measured at radiographs. RESULTS: The single transverse-orientation cage was successfully placed in 18 patients in a stepwise technique to achieve lumbar fusion. Using this technique, the patients significantly improved clinically and radiographically at postoperative visits. CONCLUSIONS: This is the first report demonstrating the safety and efficacy of instrumented TLIF with single transverse-orientation cage for the treatment of degenerative lumbar disease. Single transverse-orientation cage via MIS-TLIF approach can maintain greater lumbar lordosis and avoid the unique complications of lateral transpsoas approach. Understanding the options for cage placement is important for surgeons considering the use of this technique.

WITHDRAWN: Hypoxia-induced STAT3 contributes to chemoresistance and epithelial-mesenchymal transition in prostate cancer cells.

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Fusion techniques for adult isthmic spondylolisthesis: a systematic review.

INTRODUCTION: Various fusion techniques have been used to treat lumbar spine isthmic spondylolisthesis (IS) in adults, including anterior lumbar interbody fusion (ALIF), posterior lumbar interbody fusion (PLIF), transforaminal lumbar interbody fusion (TLIF), posterolateral fusion (PLF), and circumferential fusion. The objective of this study was to evaluate which fusion technique provides the best clinical and radiological outcome for adult lumbar IS. MATERIALS AND METHODS: A systematic review was performed. MEDLINE databases and reference lists of selected articles were searched. Inclusion criteria stated that the studies had to be controlled and that they compared clinical and radiological outcomes of various fusion techniques for treating adult IS. Exclusion criteria were use of only one treatment and non-English language articles. Two reviewers independently extracted relevant data from each included study. Statistical comparisons were made when appropriate. RESULTS: Nine studies that compared two surgical approaches to IS were included in this systematic review. Three were prospective studies, and six were retrospective studies. Two studies compared ALIF with instrumented PLF and ALIF with percutaneous pedicle screw fixation, two studies compared ALIF and TLIF, and five studies compared PLIF and PLF. ALIF was superior to other techniques regarding restoration of disc height, segmental lordosis, and whole lumbar lordosis. TLIF had lower complication rates. ALIF combined with PLF showed lower nonfusion rates than other techniques. However, there were no significant differences in clinical outcomes between any two techniques. CONCLUSION: Compared to other fusion techniques, TLIF shows fewer complications, ALIF shows better sagittal alignment, and circumferential fusion showed better fusion rates. It was difficult to make recommendations about the optimal approach because of the methodological variance in the publications.

Comparison of unilateral versus bilateral pedicle screw fixation in degenerative lumbar diseases: a meta-analysis.

PURPOSE: Traditionally, lumbar spinal surgery is performed with bilateral pedicle screw fixation to provide stability as the fusion heals. However, many studies have reported that unilateral pedicle screw fixation is as effective as bilateral constructs. To compare the clinical outcomes, complications, and surgical trauma between the two techniques for treatment of degenerative lumbar diseases, we conducted a meta-analysis. METHODS: We searched MEDLINE, EMBASE, PubMed, Google Scholar, and Cochrane databases for relevant controlled studies up to August 2013 that compared unilateral with bilateral fixation for the treatment of degenerative lumbar diseases. We independently performed title/abstract screening and full-text screening. A random effects model was used for heterogeneous data; otherwise, a fixed effect model was used, pooling data using mean difference (MD) for continuous outcomes and odds ratio (OR) for dichotomous outcomes. RESULTS: A total of 12 articles (865 participants) were eligible. Overall, there were significant differences between the two groups for blood loss (MD = -171.73, 95 % CI = -281.70 to -61.76; p = 0.002), operation time (MD = -66.02, 95 % CI = -115.52 to -16.51; p = 0.009), and fusion rate (OR = 0.50, 95 % CI = 0.26-0.96; p = 0.004). However, there were no significant differences in hospital stay (MD = -4.44, 95 % CI = -13.37 to 4.50), ODI (MD = -0.09, 95 % CI = -0.59 to 0.42; p = 0.74), JOA (MD = 0.18, 95 % CI = -0.77 to 1.14; p = 0.71), VAS (MD = -0.04, 95 % CI = -0.16 to 0.08; p = 0.49), SF-36 (PF: MD = -1.11, 95 % CI = -4.38 to 2.17, p = 0.51; GH: MD = 1.22, 95 % CI = -2.17 to 4.60, p = 0.48; MH: MD = -0.22, 95 % CI = -3.83 to 3.38, p = 0.90) and complications (OR = 1.15, 95 % CI = 0.72-1.85; p = 0.56). CONCLUSIONS: This meta-analysis shows that there was significantly less blood loss in unilateral group and less operating time; however, the fusion rate was significantly higher in the bilateral group. The outcomes of hospital stay, ODI, JOA, VAS, SF-36 score, and complications are similar in the two groups.

Is anterior cervical discectomy and fusion superior to corpectomy and fusion for treatment of multilevel cervical spondylotic myelopathy? A systemic review and meta-analysis.

OBJECTIVE: Both anterior cervical discectomy with fusion (ACDF) and anterior cervical corpectomy with fusion (ACCF) are used to treat cervical spondylotic myelopathy (CSM), however, there is considerable controversy as to whether ACDF or ACCF is the optimal treatment for this condition. To compare the clinical outcomes, complications, and surgical trauma between ACDF and ACCF for the treatment of CSM, we conducted a meta-analysis. METHODS: We conducted a comprehensive search in MEDLINE, EMBASE, PubMed, Google Scholar and Cochrane databases, searching for relevant controlled trials up to July 2013 that compared ACDF and ACCF for the treatment of CSM. We performed title and abstract screening and full-text screening independently and in duplicate. A random effects model was used for heterogeneous data; otherwise, a fixed effect model was used to pool data, using mean difference (MD) for continuous outcomes and odds ratio (OR) for dichotomous outcomes. RESULTS: Of 2157 citations examined, 15 articles representing 1372 participants were eligible. Overall, there were significant differences between the two treatment groups for hospital stay (M = -5.60, 95% CI = -7.09 to -4.11), blood loss (MD = -151.35, 95% CI = -253.22 to -49.48), complications (OR = 0.50, 95% CI = 0.35 to 0.73) and increased lordosis of C2-C7 (MD = 3.70, 95% CI = 0.96 to 6.45) and fusion segments angles (MD = 3.38, 95% CI = 2.54 to 4.22). However, there were no significant differences in the operation time (MD = -9.34, 95% CI = -42.99 to 24.31), JOA (MD = 0.24, 95% CI = -0.10 to 0.57), VAS (MD = -0.06, 95% CI = -0.81 to 0.70), NDI (MD = -1.37, 95% CI  = -3.17 to 0.43), Odom criteria (OR = 0.88, 95% CI = 0.60 to 1.30) or fusion rate (OR = 1.17, 95% CI = 0.34 to 4.11). CONCLUSIONS: Based on this meta-analysis, although complications and increased lordosis are significantly better in the ACDF group, there is no strong evidence to support the routine use of ACDF over ACCF in CSM.

Prognostic value of human equilibrative nucleoside transporter1 in pancreatic cancer receiving gemcitabin-based chemotherapy: a meta-analysis.

BACKGROUND: The potential prognostic value of human equilibrative nucleoside transporter1 in pancreatic cancer receiving gemcitabine-based chemotherapy is variably reported. OBJECTIVE: The objective of this study was to conduct a systematic review of literature evaluating human equilibrative nucleoside transporter1 expression as a prognostic factor in pancreatic cancer receiving gemcitabine-based chemotherapy and to conduct a subsequent meta-analysis to quantify the overall prognostic effect. METHODS: Related studies were identified and evaluated for quality through multiple search strategies. Only studies analyzing pancreatic cancer receiving gemcitabine-based chemotherapy were eligible for inclusion. Data were collected from studies comparing overall, disease-free and progression-free survival (OS, DFS and PFS) in patients with low human equilibrative nucleoside transporter1 levels and those having high levels. The hazard ratio (HR) and its 95% confidence interval (95%CI) were used to assess the strength of associations. Hazard ratios greater than 1 reflect adverse survival associated with low human equilibrative nucleoside transporter1 levels. RESULTS: A total of 12 studies (n = 875) were involved in this meta-analysis (12 for OS, 5 for DFS, 3 for PFS). For overall and disease-free survival, the pooled HRs of human equilibrative nucleoside transporter1 were significant at 2.93 (95% confidence interval [95% CI], 2.37-3.64) and 2.67 (95% CI, 1.87-3.81), respectively. For progression-free survival, the pooled HR in higher human equilibrative nucleoside transporter1 expression in pancreatic cancer receiving gemcitabine-based chemotherapy was 2.76 (95% CI, 1.76-4.34). No evidence of significant heterogeneity or publication bias was seen in any of these studies. CONCLUSION: These results support the case for a low human equilibrative nucleoside transporter1 level representing a significant and reproducible marker of adverse prognosis in pancreatic cancer receiving gemcitabine-based chemotherapy.

Internalization of hydroxyapatite nanoparticles in liver cancer cells.

Hydroxyapatite (HAP) is the main inorganic component of hard tissues and shows excellent biocompatibility and osteoconductivity properties. Nanoparticles of HAP can be synthesised by the precipitation method in distilled water. The needle shaped particles are below 100 nm in size with low-crystallinity and high-surfacial activation. Recent studies showed toxic effects of HAP nanoparticles on cancer cells. Other studies focus on the application of HAP nanoparticles as drug and gene delivery system or cell marker. However, to date, the exact internalization pathway of HAP nanoparticles into cells has not been determined. When HAP nanoparticles were added to cell culture medium, the particles immediately became instable and formed agglomerates with a size of about 500-700 nm. Hence, cells seldom encounter single HAP nanoparticles in the environment of cell culture or body fluid. The TEM showed internalized HAP captured by vacuoles in the cytoplasm of the hepatocellular carcinoma cells. The invaginations in the cell membrane before nanoparticle uptake suggested endocytic pathways as internalization mechanism. This study revealed that agglomerated HAP nanoparticles were internalized by cells through the energy-dependent process of clathrin-mediated endocytosis. Depletion of intracellular potassium arrested the formation of coated pit, which inhibited the uptake of HAP.

Static friction of porous bioceramic beta-TCP on intestinal mucus films.

The static friction behavior between a porous bioceramic material and an intestinal mucus film was investigated in order to develop a new intestine robotic endoscope. Here, the friction couple is porous beta-tricalcium phosphate (beta-TCP) and an artificial intestine mucus film. The effect of pore size of the beta-TCP material on the friction behavior is investigated. The results illustrated that in this friction system there is a relatively small normal force upon the intestinal mucus film of the intestine wall during locomotion. The maximum static friction force in this friction couple varies with the pore size of the porous beta-TCP material.

Effect of hydroxyapatite nanoparticles on the ultrastructure and function of hepatocellular carcinoma cells in vitro.

The interaction of Bel-7402 hepatocellular carcinoma cells (HCC) as a single cell suspension with hydroxyapatite (HAP) nanoparticles was investigated. It was observed by an inverted microscope that the cells were still homogeneously distributed in the culture medium after 24 h. A TEM analysis showed that the HAP nanoparticles attached to the Bel-7402 cells were finally swallowed by the cells after 4 h, and induced ultrastructural changes of the cells after 4 days. A MTT assay and cell count test for the HAP nanoparticles of various concentrations from 0.14 to 0.56 mmol L(-1) showed that the HAP nanoparticles at a concentration of 0.56 mmol L(-1) induced the strongest effect on the inhibition of Bel-7402 cell proliferation and induced a dramatic decline in cell numbers. Proliferation of Bel-7402 was inhibited by more than 70%, compared to the control. A cell cycle analysis revealed that HAP can arrest Bel-7402 cells at the G1 phase with increasing effect over time. These findings demonstrated that HAP can enter into HCC very easily, change their ultrastructure, and evidently suppress their proliferation.