Risk factor of contralateral radiculopathy following microendoscopy-assisted minimally invasive transforaminal lumbar interbody fusion.

PURPOSE: Microendoscopy-assisted minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) is an advantageous method for treating lumbar degenerative disease; however, some patients show contralateral radiculopathy postoperatively. This study aims to investigate its risk factor. METHODS: A total of 130 cases who underwent microendoscopy-assisted MIS-TLIF at L4-5 level were divided into symptomatic and asymptomatic groups according to the presence of postoperative contralateral radiculopathy. Both preoperative and postoperative radiographic parameters, as well as their changes were compared between the two groups, including lumbar lordosis (LL), surgical segmental angle (SSA), disc height (DH), contralateral foramen area (CFA) and contralateral canal area (CCA). Screw breach on contralateral L4 pedicle and decompression method (ipsilateral or bilateral canal decompression through unilateral route) were also analyzed as potential risk factors. Receiver operating characteristic (ROC) curve was drawn for the risk factor to determine the optimal threshold for predicting postoperative contralateral radiculopathy. Besides, clinical outcome assessment, involving Visual Analog Score (VAS) for back and leg, Japanese Orthopaedics Association Score (JOA) and Oswestry Disability Index (ODI), was also compared between the two groups before surgery and at final follow-up (at least 3 months after the surgery for asymptomatic patients or final treatments of contralateral radiculopathy for symptomatic cases). RESULTS: Postoperative contralateral radiculopathy occurred in 11 (8.5%) of the 130 patients. Both preoperative and postoperative CFA as well as its change were significantly decreased in symptomatic group compared with asymptomatic group (all P < 0.05). For the remaining four parameters (LL, SSA, DH, CCA), their preoperative, postoperative and change values showed no statistical difference between the two groups (all P > 0.05). Neither screw breach nor decompression method revealed statistical association with this complication (both P > 0.05). Based on ROC curve, the optimal threshold of preoperative CFA was 0.76 cm2. At final follow-up, significant improvement in VAS (back and leg), JOA and ODI was observed in both groups compared with preoperative baseline (all P < 0.05), while no difference was found between the two groups (all P > 0.05). CONCLUSIONS: Preoperative contralateral foramen stenosis is the risk factor of contralateral radiculopathy following microendoscopy-assisted MIS-TLIF. If preoperative CFA at L4-5 level is not larger than 0.76 cm2, prophylactic measures, including both indirect and direct decompression of contralateral foramen, are recommended.

Spinal coronal profiles and proximal femur bone mineral density in adolescent idiopathic scoliosis.

PURPOSE: Although the occurrence and progression of AIS has been linked to low bone mineral density (BMD), the relationships between spinal curvature and bilateral differences in proximal femur BMD are controversial. Few correlation studies have stratified patients by curve type. The purpose of this study was to evaluate the relationships between spinal coronal profile and bilateral differences in proximal femur BMD in patients with adolescent idiopathic scoliosis (AIS). METHODS: This study included 67 patients with AIS who underwent posterior correction and fusion surgery between January 2009 and October 2011. The mean age at the time of surgery was 17.4 ± 4.1 years. Bilateral proximal femur BMD was measured before surgery by dual-energy X-ray absorptiometry. We compared the proximal femur BMDs by determining the bilateral BMD ratio (left proximal femur BMD divided by that of the right). We evaluated correlations between coronal parameters, obtained from preoperative radiographs, and the BMD ratio using Pearson's correlation analysis. RESULTS: Patients with Lenke type 1 curve (48; all with a right convex curve) had a mean bilateral proximal femur BMD ratio of 1.00 ± 0.04. Patients with Lenke type 5 curve (19; all with a left convex curve) had a mean bilateral proximal femur BMD ratio of 0.94 ± 0.04, indicating that the BMD in the proximal femur on the right side (concave) was greater than that in the left (convex). Coronal balance was significantly correlated with the BMD ratio in both the Lenke type 1 and type 5 groups, with a correlation coefficient of 0.46 and 0.50, respectively. CONCLUSIONS: The bilateral proximal femur BMD ratio was significantly correlated with the coronal balance in AIS patients. When the C7 plumb line was shifted toward one side, the BMD was greater in the contralateral proximal femur.

Performance Evaluation of the Fully Automated NeuMoDx RT-PCR Platform for the Quantification of CMV and EBV DNA in EDTA Plasma: Implications for Clinical Management and Establishment of a Conversion Formula.

The NeuMoDx96 platform is a fully automated real-time PCR (RT-PCR) system. To provide continued testing quality with the introduction of new assays, the primary aim of this study was to evaluate the analytical and clinical performance of the NeuMoDx platform for the detection and quantification of CMV and EBV DNA in EDTA plasma. As no conversion from log10 international units per milliliter to copies per milliliter was provided, the secondary aim was to calculate and establish a conversion factor for the output of results in copies per milliliter for CMV and EBV. Archived ETDA plasma samples (cytomegalovirus [CMV], n = 290; Ebstein-Barr virus [EBV], n = 254) were used to evaluate the analytical performance of the NeuMoDx96 platform against the routine real-time quantitative PCR (qPCR) assays. Additionally, the first WHO international standards (WHO-IS) for CMV (n = 70) and EBV (n = 72) were used for the calculation of the intra- and interassay variation. WHO-IS qualitative agreement between the assays was 100%. Intra-assay variability was low for both CMV assays (coefficient of variation [CV], phosphate-buffered saline [PBS], 3 log10 IU/mL NeuMoDx, 3.67%; Abbott RealTime, CMV, 3.35%) and NeuMoDx EBV assay (CV, PBS, 3 log10 IU/mL, 3.05%) but high for the Altona EBV assay (CV, PBS, 3 log10 IU/mL, 26.13%). The overall qualitative concordance in clinical samples was 96.8% (270/279) for CMV and 96.7% (237/245) for EBV. The mean difference between the assays was -0.2 log10 IU/mL (CMV) and -0.18 log10 IU/mL (EBV). High qualitative concordance and a significant correlation of quantitative values for both assays make NeuMoDx CMV and EBV assays suitable for routine diagnostic testing. The new RT-PCR system and conversion formulas to report results in copies per milliliter are now applied in clinical routine testing. IMPORTANCE Clinical management of solid organ transplant (SOT) patients requires the careful monitoring of immunosuppression and viral infection or reactivation. qPCR is the gold standard for the detection and quantification of very small amounts of viral DNA and allows for an early assessment of viral load kinetics. The tested NeuMoDx 96 platform provides faster results than the previously used RT-PCR workflows for CMV (Abbott m2000 and RealTime CMV assay) and EBV (LightCycler 480 II, Roche high pure extraction, and Altona RealStar EBV assay) DNA detection. The implemented conversion formulas allow the continued reporting in clinically established copies per milliliter, important for long-term care of SOT patients.

[Spectra and structural analysis of high boiling solvent lignin from Bagasse].

Bagasse high boiling solvent lignin is a polymer prepared by high boiling solvent pulping process. In the IR spectra, the absorbance of HBS lignin at 1700 and 1 328 cm(-1) is present. It is showed that the nonconjugated carbonyl existed. The strong absorbance of UV spectra of HBS lignin is about 201 nm for n-->pi electron transition, which indicates that the HBS lignin is an unsaturated polymer. Judged from the 1H NMR, the syringyl and guaiacyl group in the lignin is present. The element composition and the content of OCH3 group were investigated. The empirical C9-formula of the lignin is C9H9.79O2.58(OCH)0.75 according to dealing with the experiment data. The weight-average molecular weight of the HBS lignin is 2674 g x mol(-1).

Reliability Analysis of Spino-Pelvic Parameters in Adult Spinal Deformity: A Comparison of Whole Spine and Pelvic Radiographs.

STUDY DESIGN: Retrospective study. OBJECTIVE: To examine the reliabilities of sagittal spino-pelvic alignment measurements using whole spine-pelvic and local pelvic radiographs and to determine whether spinal deformity affects these reliabilities. SUMMARY OF BACKGROUND DATA: Sagittal spino-pelvic alignment is important in adult spinal deformity patients (ASD). Spino-pelvic parameters are closely related to health-related quality of life and indispensable for surgical planning. However, few studies have focused on the reliability of these measurements. METHODS: Three spino-pelvic parameters, pelvic incidence (PI), pelvic tilt (PT), and sacral slope (SS) were measured in 2 patient groups: 33 adult scoliosis (AS) and 33 nondeformity (ND) patients, using whole spine-pelvic lateral radiographs (whole spine radiographs) and local pelvic lateral radiographs (local pelvic radiographs), by 5 experienced spine surgeons. Intra- and interobserver reliabilities for each procedure were evaluated by intraclass correlation coefficients (ICC). The interobserver reliability differences between the 2 procedures were statistically evaluated. The difference between the largest and smallest measurements among the 5 observers was also evaluated in the AS and ND groups. RESULTS: Measurement of the 3 parameters using whole spine or local pelvic radiographs showed good to excellent intraobserver reliability (range of ICC: 0.820-0.935). The interobserver reliabilities of PI and PT from local pelvic radiographs were significantly higher than those from whole spine radiographs (P < 0.002). The intraobserver reliabilities of PI and PT from pelvic radiographs tended to be higher than those from whole spine radiographs, but the differences were not statistically significant. The reliability of SS was comparable between the 2 methods. The differences between the highest and lowest PI and PT measurements were smaller with the pelvic compared to whole spine radiographs. These findings were consistent in the AS and ND groups. CONCLUSION: Local pelvic radiography is more reliable than whole spine radiography for determining spino-pelvic parameters, and we recommend its use for evaluating ASD patients. LEVEL OF EVIDENCE: 3.

Graft of the NT-3 persistent delivery gelatin sponge scaffold promotes axon regeneration, attenuates inflammation, and induces cell migration in rat and canine with spinal cord injury.

Persistent neurotrophic factor delivery is crucial to create a microenvironment for cell survival and nerve regeneration in spinal cord injury (SCI). This study aimed to develop a NT-3/fibroin coated gelatin sponge scaffold (NF-GS) as a novel controlled artificial release therapy for SCI. In vitro, bone marrow-derived mesenchymal stem cells (MSCs) were planted into the NF-GS and release test showed that NF-GS was capable to generate a sustainable NT-3 release up to 28 days. MSCs in NF-GS had high cell activity with excellent cell distribution and phenotype. Then, the NF-GS was transplanted into the injury site of spinal cord of rat and canine in vivo, which exhibited strong biocompatibility during post-transplantation period. Four weeks following transplantation, the concentration of NT-3 was much higher than that in control groups. Cavity areas in the injury/graft site were significantly reduced due to tissue regeneration and axonal extensions associated with myelin sheath through the glial scar into the NF-GS. Additionally, the NF-GS decreased the inflammation by reducing the CD68 positive cells and TNF-α. A striking feature was the occurrence of some cells and myelin-like structure that appeared to traverse the NF-GS. The present results demonstrate that the NF-GS has the property to control the release of NT-3 from the NT-3/fibroin complex thus facilitating regeneration of injured spinal cord.

Microendoscopy-assisted minimally invasive transforaminal lumbar interbody fusion for lumbar degenerative disease: short-term and medium-term outcomes.

OBJECTIVE: To evaluate short-term and medium-term outcomes of microendoscopy-assisted minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) and open TLIF for lumbar degenerative disease. METHODS: In this prospective, randomized control study, 50 cases received microendoscopy-assisted MIS-TLIF (MIS group), while another well-matched 50 cases accepted open TLIF (open group). Parameters between both groups, including surgical duration, intraoperative blood loss and radiologic exposure, postoperative analgesic usage and ambulatory time, visual analogue scale (VAS) for back and leg, functional scores, self-evaluation of surgical outcome (modified MacNab criteria), interbody fusion rate, adjacent segment degeneration (ASD) rate, as well as complication incidence were compared at 1 month and 24 months postoperatively. RESULTS: Intraoperative blood loss and postoperative analgesic usage were significantly reduced in MIS group (P<0.05). Patients undergoing microendoscopy-assisted MIS-TLIF were able to ambulate earlier postoperatively than those receiving open TLIF (P<0.05). However, it showed prolonged surgical duration and enhanced radiologic exposure in MIS group (P<0.05). At 1 month postoperatively, MIS group was associated with more improvement of VAS and functional scores compared with open group (P<0.05). While at 24 months postoperatively, both groups revealed similar VAS and functional scores (P>0.05). Excellent and perfect scale rating by modified MacNab criteria, interbody fusion rate, ASD rate and complication incidence between both groups were nearly the same (P>0.05). CONCLUSIONS: Microendoscopy-assisted MIS-TLIF owns advantages of less iatrogenic injury, decreased blood loss, reduced analgesic usage and earlier rehabilitation, while it has drawbacks of more surgical duration and radiologic exposure. It is superior than open TLIF in terms of short-term clinical outcomes and has similar medium-term clinical outcomes.