Short term results of endoscopic discectomy in lumbar spine

A recent modification to lumbar discectomy involves the use of a micro-endoscope instead of an operating microscope for visualization. Percutaneous endoscopic lumbar discectomy (PELD) uses a rigid operating spinal endoscope that allows direct visualization and excision of contained and non-contained herniated disc fragments. The advantages of Endoscopic lumbar discectomy are remarkable due to minimal bone resection, no damage to paravertebral muscles, rapid recovery, minimally procedure related morbidity, cost-effectiveness and high patient satisfaction rate. Aims and objectives is to study and evaluate clinical and radiological outcomes of endoscopic lumbar discectomy over a period of 6 months.24 patients underwent endoscopic lumbar discectomy proven with MRI in a span of 3 years from 2018 to 2021. Every patient was followed up for 6 months in an observational, retrospective and prospective type of study and assessed on the basis of MacNab criteria, VAS pain score, Oswestry low back pain questionnaire. Mean preoperative Oswestry disability score (ODS) was 74.38 while mean postoperative ODS was found to be 29.25. Preoperative, while analyzing through Macnab criteria, poor results were seen in 95.83% of patients while fair results were seen in 4.17% of patients. Postoperatively excellent results were seen in 16.67% of patients while good results were seen in 83.34% of patients. Mean preoperative VAS was 7.33 while mean postoperative VAS was found to be 2.91. Endoscopic discectomy is a safe and effective procedure where patient satisfaction and pain relief are not compromised. It may be an effective and alternative treatment option for the upward migration of disc herniation in the upper lumbar area and offers additional advantage for early mobilization and faster improvement

New classification of S1 pedicle morphometry impacting pedicle screw insertion technique

Background: The conventional entry point for the S1 pedicle screw insertion has been described as ‘at the base of and lateral to the superior S1 superior facet’. However, many orthopaedic surgeons complain that this technique is extremely demanding and is faced with many challenges in execution. Therefore, alternative entry points and modifications of existing techniques are explored for a greater convenience.Methods: We conducted a survey amongst 136 spine surgeons on the technical difficulties faced during insertion of the S1 pedicle screw. We also classified the S1 pedicles based by measuring their geometric parameters on 100 random computed tomography (CT) images.Results: The S1 pedicle entry technique was considered to be the most difficult and challenging by the orthopaedic surgeons in our survey due to an inadequate medial angulation due to paraspinal muscle mass tension and an overhanging iliac crest. This could be explained by the hourglass shaped pedicle (type 3) with a desired medial angle more 50 degrees (type III) observed as the most common S1 pedicle in the study population. To overcome this limitation, most of them preferred a tri-corticate approach.Conclusions: A more lateral entry point and a longer screw might be considered as solutions for a better and safer S1 pedicle entry. Also, the use of pre-operative CT can be considered to visualize the type of S1 pedicle and hence, decide on the most appropriate technique of screw insertion.

A genome scale metabolic network for rice and accompanying analysis of tryptophan, auxin and serotonin biosynthesis regulation under biotic stress

Background Functional annotations of large plant genome projects mostly provide information on gene function and gene families based on the presence of protein domains and gene homology, but not necessarily in association with gene expression or metabolic and regulatory networks. These additional annotations are necessary to understand the physiology, development and adaptation of a plant and its interaction with the environment. Results RiceCyc is a metabolic pathway networks database for rice. It is a snapshot of the substrates, metabolites, enzymes, reactions and pathways of primary and intermediary metabolism in rice. RiceCyc version 3.3 features 316 pathways and 6,643 peptide-coding genes mapped to 2,103 enzyme-catalyzed and 87 protein-mediated transport reactions. The initial functional annotations of rice genes with InterPro, Gene Ontology, MetaCyc, and Enzyme Commission (EC) numbers were enriched with annotations provided by KEGG and Gramene databases. The pathway inferences and the network diagrams were first predicted based on MetaCyc reference networks and plant pathways from the Plant Metabolic Network, using the Pathologic module of Pathway Tools. This was enriched by manually adding metabolic pathways and gene functions specifically reported for rice. The RiceCyc database is hierarchically browsable from pathway diagrams to the associated genes, metabolites and chemical structures. Through the integrated tool OMICs Viewer, users can upload transcriptomic, proteomic and metabolomic data to visualize expression patterns in a virtual cell. RiceCyc, along with additional species-specific pathway databases hosted in the Gramene project, facilitates comparative pathway analysis. Conclusions Here we describe the RiceCyc network development and discuss its contribution to rice genome annotations. As a case study to demonstrate the use of RiceCyc network as a discovery environment we carried out an integrated bioinformatic analysis of rice metabolic genes that are differentially regulated under diurnal photoperiod and biotic stress treatments. The analysis of publicly available rice transcriptome datasets led to the hypothesis that the complete tryptophan biosynthesis and its dependent metabolic pathways including serotonin biosynthesis are induced by taxonomically diverse pathogens while also being under diurnal regulation. The RiceCyc database is available online for free access at http://www.gramene.org/pathway

Amplification of Fluctuations in Unstable Systems with Disorder

We study the early-stage kinetics of thermodynamically unstable systems with quenched disorder. We show analytically that the growth of initial fluctuations is amplified by the presence of disorder. This is confirmed by numerical simulations of morphological phase separation (MPS) in thin liquid films and spinodal decomposition (SD) in binary mixtures. We also discuss the experimental implications of our results.Comment: 15 pages, 4 figure