Microfluidic extensional flow device to study mass transfer dynamics in the polymer microparticle formation process.

Polymer microparticles are often used to encapsulate drugs for sustained drug-release treatments. One of the ways they are manufactured is by using a solvent extraction process, in which the polymer solution is emulsified into an aqueous bulk phase using a surfactant as a stabilizing agent, followed by the removal of the solvent. The radius of a polymer drop decreases as a function of time until the polymer reaches the gelling point, after which it is separated and dried. Among the various operating parameters, the rate of solvent extraction is a critical step that affects the morphology and porosity, and consequently, the kinetics of drug release. But a fundamental mechanistic understanding of the solvent extraction dynamics as a function of shear is still unexplored. In this study, we have developed an experimental mass transfer model to predict the extraction by using the microfluidic extensional flow device (MEFD) to probe the shear and extraction dynamics at the level of a single drop in a linear extensional flow field. We used a computer-controlled feedback algorithm to manipulate the flow field and hydrodynamically trap a Hele-Shaw drop and observe the extraction process. For the polymer solution, we used a biocompatible polymer, poly-lactic-co-glycolic acid (PLGA) with ethyl acetate (EtOAc) as the solvent. Our experiments were conducted by varying the extensional rate (G) in the channel from ∼0.1 s-1 to ∼10 s-1, and using an analytical solution of the flow field, we captured the dissolution process and measured the change in drop radius (R) with time (t). Interestingly, we initially observed a short-time asymptote R ∼ t, and later the long-time asymptote of R = constant; both trends were physically explained. The transport model developed in this work can be used to predict extraction rates and polymer microparticle composition for any polymer-solvent system. This work is also an important contribution to the literature on convective mass transfer in partially miscible emulsions.

Risk Predictive Score and Cord Morphology Classification for Intraoperative Neuromonitoring Alerts in Kyphosis Surgery.

BACKGROUND: Intraoperative neuromonitoring (IONM) alert is one of the worrying events of kyphosis corrective surgery, which can result in a postoperative neurological deficit. To our knowledge, there is no risk prediction score to predict such events in patients undergoing kyphosis surgery. PURPOSE: To develop a new preoperative MRI-based cord morphology classification (CMC) and risk prediction score for predicting IONM alerts in patients with kyphotic deformity. STUDY DESIGN: Retrospective analysis of prospectively collected data PATIENT SAMPLE: 114 patients undergoing surgical correction for kyphotic deformity OUTCOME MEASURES: Intraoperative neuromonitoring alerts and postoperative neurological status using AIS grading. METHODS: Kyphotic deformity patients undergoing posterior spinal fusion were retrospectively reviewed. Based on the morphology of the spinal cord and surrounding CSF in MRI, there are five types of cord. Type 1 (normal cord): circular cord with surrounding visible CSF between the cord and the apex, Type 2 (flattened cord): cord with < 50% distortion at the apex with obliteration of the anterior CSF; Type 3 (deformed cord): cord with > 50% distortion at the apex with complete obliteration of the surrounding CSF; Type 4 (stretched cord): the cord is stretched and atrophied over the apex of the curve. Type 5 (translated cord): horizontal translation of the cord at the apex with buckling collapse of the vertebral column. Preoperative radiographs were used to measure the preoperative sagittal cobbs angle, sagittal deformity angular ratio (S-DAR), sagittal vertical axis (SVA), apex of the curve, and type of kyphosis. Clinical data like the duration of symptoms, clinical signs of myelopathy, neurological status (AIS grade), grade of myelopathy using the mJOA score, and type of osteotomy were documented. Multivariate logistic regression was used to determine the risk factors for IONM alerts and the risk prediction score was developed which was validated with new cohort of 30 patients. RESULTS: A total of 114 patients met the inclusion criteria. IONM alerts were documented in 33 patients (28.9%), with full recovery of the signal in 25 patients and a postoperative deficit in 8 patients. Rate of IONM alerts was significantly higher in Type 5 (66%), followed by Type 4 (50%), Type 3 (21.1%), Type 2 (11.1%), and Type 1 (11.1%) (p-value < 0.001). Based on multiple logistic regression, seven factors, namely preoperative neurological status, mJOA score ≤ 6, presence of signs of myelopathy, apex of the curve above T5, preoperative sagittal cobbs, S-DAR, and MRI-based CMC, were identified as risk predictors. The value for the risk factors varies from 0 to 4, and the maximum total risk score was 13. The cut-off value of 6 had good sensitivity (84.9%) and specificity (77.8%) indicating a high risk for IONM alerts. The AUC of the predictive model was 0.92, indicating excellent discriminative ability. CONCLUSION: We developed and validated a risk predictive score that identifies patients at risk of IONM alerts during kyphosis surgery. Identification of such high-risk patients (risk score ≥ 6) helps in proper evaluation and preoperative counselling and helps in providing a proper evidence-based reference for treatment strategies.

"Does the Gut microbiome influence disc health and disease?-the interplay between dysbiosis, pathobionts, and disc inflammation: a Pilot Study".

BACKGROUND CONTEXT: Gut microbiome alterations resulting in inflammatory responses have been implicated in many distant effects on different organs. However, its influence on disc health is still not fully investigated. PURPOSE: Our objective was to document the gut biome in healthy volunteers and patients with disc degeneration and to understand the role of gut dysbiosis on human disc health. STUDY DESIGN: Experimental case-control study. PATIENT SAMPLE: We included 40 patients with disc degeneration (DG) and 20 healthy volunteers (HV). HV comprised of age groups 30 to 60 years with no known record of back pain and no clinical comorbidities, with normal MRI. Diseased group (DG) were patients in the same age group undergoing surgery for disc disease (disc herniation-25; discogenic stenosis-15) and without instability (with Modic-20; and non-Modic-20). OUTCOME MEASURES: N/A. METHODS: We analyzed 16S V3-V4 rDNA gut metagenome from 20 healthy volunteers (HV) and compared the top signature genera from 40 patients with disc degeneration (DG) across Modic and non-Modic groups. Norgen Stool DNA Kit was used for DNA extraction from ∼200 mg of each faecal sample collected using the Norgen Stool Collection Kit.16S V3-V4 rDNA amplicons were generated with universal bacterial primers 341F and 806R and amplified with Q5 High-Fidelity DNA Polymerase. Libraries were sequenced with 250×2 PE to an average of 0.1 million raw reads per sample (Illumina Novaseq 6000). Demultiplexed raw data was assessed with FastQC, and adapter trimmed reads >Q30 reads were processed in the QIME2 pipeline. Serum C-reactive protein (CRP) was measured by the immunoturbimetry method and Fatty acid-binding protein 5 (FABP5) was measured in albumin-globulin-depleted plasma through global proteome analysis. RESULTS: We observed significant gut dysbiosis between HV and DG and also between the Modic and non-Modic groups. In the Modic group, commensals Bifidobacterium and Ruminococcus were significantly depleted, while pathobionts Streptococcus, Prevotella, and Butryvibrio were enriched. Firmicutes/Bacteroidetes ratio was decreased in DG (Modic-0.62, non-Modic-0.43) compared to HV (0.70). Bacteria-producing beneficial short-chain fatty acids were also depleted in DG. Elevated serum CRP and increased FABP5 were observed in DG. CONCLUSION: The study revealed gut dysbiosis, an altered Firmicutes/Bacteroidetes ratio, reduced SCFA-producing bacteria, and increased systemic and local inflammation in association with disc disease, especially in Modic changes. The findings have considerable importance for our understanding and prevention of disc degeneration.

Neuromonitoring Signal Changes in Degenerative Cervical Myelopathy: An Analysis of Risk Factors for Signal Drops During Posterior Cervical Decompression.

OBJECTIVE: To analyze intraoperative neuromonitoring data of patients with degenerative cervical myelopathy undergoing cervical laminectomy and assess the incidence of signal drops and their risk factors. METHODS: This retrospective observational study included patients with degenerative cervical myelopathy who underwent cervical laminectomy with intraoperative neuromonitoring between July 2018 and March 2023. We analyzed the signal changes for any correlation with the type of pathology (ossified posterior longitudinal ligament vs. cervical spondylotic myelopathy [CSM]) and clinical (severity of myelopathy, duration of symptoms) and radiological (length of cord signal changes and K-line) parameters. RESULTS: Of 100 degenerative cervical myelopathy cases, 55 were diagnosed as OPLL and 45 as CSM. Signal drops were recorded in 26 patients-14 persistent drops and 12 transient drops. True positive drops were seen in 4 patients (2 OPLL and 2 CSM), 3 of whom had sustained bimodal drops (both somatosensory evoked potentials and motor evoked potentials). Signal drops were significantly more frequent with OPLL compared with CSM (P < 0.01). Ten of 14 persistent signal drops and 9 of 12 transient drops were seen in patients in OPLL. Continuous OPLL, negative K-line, hill type OPLL, severity of myelopathy, and longer duration of symptoms were risk factors for signal drops. CONCLUSIONS: Patients with cervical OPLL have a higher incidence of false positive and transient signal drops after decompression compared with patients with CSM. Longer duration of symptoms, high-grade myelopathy, continuous OPLL, hill type OPLL, and negative K-line were risk factors for signal drops.

Efficacy and Safety of Ultrasound Guided Inter-semispinal Plane Block for Postoperative Analgesia in Posterior Cervical Laminectomy - A Prospective Randomised Controlled Study.

STUDY DESIGN: Prospective, randomized controlled study. OBJECTIVE: To assess the safety and efficacy of an ultrasound-guided ISP block for postoperative analgesia in posterior cervical laminectomy. METHODS: 88 patients requiring posterior cervical laminectomy were randomized into two groups, those who underwent ISP block with multimodal analgesia (ISPB group) and those with only multimodal analgesia (control group). Demographic details, intraoperative parameters (blood loss, duration of surgery, perioperative total opioid consumption, muscle relaxants used), and postoperative parameters (numeric rating scale, satisfaction score, mobilization time, and complications) were recorded. RESULTS: The total opioid consumption (128.41 + 39.65vs 284.09 + 140.92mcg; P < .001), muscle relaxant usage (46.14 + 6.18 mg vs 59.32 + 3.97 mg; P < .001), surgical duration (128.61 + 26.08/160.23 + 30.99mins; P < .01), and intra-operative blood loss (233.18 + 66.08 mL vs 409.77 + 115.41 mL; P < .01) were significantly less in the ISPB group compared to the control. In the postoperative period, the control group's pain score was significantly higher (P < .001) in the initial 48 hours. The Modified Observer Alertness/Sedation Score (MOASS) score and satisfaction scores were significantly better in the ISPB compared to the control (P < .001). The mean time required to ambulate was statistically less in ISPB (4.30 + 1.64hours) when compared to controls (9.48 + 3.07hours) (P < .001). CONCLUSION: In patients undergoing posterior cervical laminectomy, ISP block is a safe and effective technique with better outcomes than standard multi-modal analgesia alone, in terms of reduced intra-operative opioid requirements and blood loss, better postoperative analgesia, and early mobilization.

Orthopedic postoperative infection profile and antibiotic sensitivity of 2038 patients across 24 countries - Call for region and institution specific surgical antimicrobial prophylaxis.

Purpose: Improper utilization of surgical antimicrobial prophylaxis frequently leads to increased risks of morbidity and mortality.This study aims to understand the common causative organism of postoperative orthopedic infection and document the surgical antimicrobial prophylaxis protocol across various institutions in to order to strengthen surgical antimicrobial prophylaxis practice and provide higher-quality surgical care. Methods: This multicentric multinational retrospective study, includes 24 countries from five different regions (Asia Pacific, South Eastern Africa, Western Africa, Latin America, and Middle East). Patients who developed orthopedic surgical site infection between January 2021 and December 2022 were included. Demographic details, bacterial profile of surgical site infection, and antibiotic sensitivity pattern were documented. Results: 2038 patients from 24 countries were included. Among them 69.7 % were male patients and 64.1 % were between 20 and 60 years. 70.3 % patients underwent trauma surgery and instrumentation was used in 93.5 %. Ceftriaxone was the most common preferred in 53.4 %. Early SSI was seen in 55.2 % and deep SSI in 59.7 %. Western Africa (76 %) and Asia-Pacific (52.8 %) reported a higher number of gram-negative infections whereas gram-positive organisms were predominant in other regions. Most common gram positive organism was Staphylococcus aureus (35 %) and gram-negative was Klebsiella (17.2 %). Majority of the organisms showed variable sensitivity to broad-spectrum antibiotics. Conclusion: Our study strongly proves that every institution has to analyse their surgical site infection microbiological profile and antibiotic sensitivity of the organisms and plan their surgical antimicrobial prophylaxis accordingly. This will help to decrease the rate of surgical site infection, prevent the emergence of multidrug resistance and reduce the economic burden of treatment.

Double Level Non-Contiguous Traumatic Lumbar Disc Herniation Presenting With Cauda Equina Syndrome: A Case Report and Literature Review.

CASE: A 52-year-old man presented with cauda equina syndrome after a motorcycle accident. Magnetic resonance imaging revealed traumatic disc herniation, at L2-L3 and L5-S1 levels without bony injury. He was managed successfully by wide laminectomy and microdiscectomy at both levels with complete neurological recovery at 2-month follow-up. CONCLUSION: With a reported incidence of 0.4%, traumatic disc herniation in the lumbar region is an uncommon occurrence that may resemble a spinal epidural hematoma in acute trauma. Although MRI may not reliably differentiate spinal epidural hematoma from disc herniation, urgent surgical intervention may be required in profound neurological deficits.

ERMA (TMEM94) is a P-type ATPase transporter for Mg2+ uptake in the endoplasmic reticulum.

Intracellular Mg2+ (iMg2+) is bound with phosphometabolites, nucleic acids, and proteins in eukaryotes. Little is known about the intracellular compartmentalization and molecular details of Mg2+ transport into/from cellular organelles such as the endoplasmic reticulum (ER). We found that the ER is a major iMg2+ compartment refilled by a largely uncharacterized ER-localized protein, TMEM94. Conventional and AlphaFold2 predictions suggest that ERMA (TMEM94) is a multi-pass transmembrane protein with large cytosolic headpiece actuator, nucleotide, and phosphorylation domains, analogous to P-type ATPases. However, ERMA uniquely combines a P-type ATPase domain and a GMN motif for ERMg2+ uptake. Experiments reveal that a tyrosine residue is crucial for Mg2+ binding and activity in a mechanism conserved in both prokaryotic (mgtB and mgtA) and eukaryotic Mg2+ ATPases. Cardiac dysfunction by haploinsufficiency, abnormal Ca2+ cycling in mouse Erma+/- cardiomyocytes, and ERMA mRNA silencing in human iPSC-cardiomyocytes collectively define ERMA as an essential component of ERMg2+ uptake in eukaryotes.

Does Magnetic Resonance Imaging Predict Neurological Deficit in Patients with Traumatic Lower Lumbar Fractures?

STUDY DESIGN: A retrospective cohort study. PURPOSE: This study aimed to understand the role of magnetic resonance imaging (MRI) in predicting neurological deficits in traumatic lower lumbar fractures (LLFs; L3-L5). OVERVIEW OF LITERATURE: Despite studies on the radiological risk factors for neurological deficits in thoracolumbar fractures, very few have focused on LLFs. Moreover, the potential utility of MRI in LLFs has not been evaluated. METHODS: In total, 108 patients who underwent surgery for traumatic LLFs between January 2010 and January 2020 were reviewed to obtain their demographic details, injury level, and neurology status at the time of presentation (American Spinal Injury Association [ASIA] grade). Preoperative computed tomography scans were used to measure parameters such as anterior vertebral body height, posterior vertebral body height, loss of vertebral body height, local kyphosis, retropulsion of fracture fragment, interpedicular distance, canal compromise, sagittal transverse ratio, and presence of vertical lamina fracture. MRI was used to measure the canal encroachment ratio (CER), cross-sectional area of the thecal sac (CSAT), and presence of an epidural hematoma. RESULTS: Of the 108 patients, 9 (8.3%) had ASIA A, 4 (3.7%) had ASIA B, 17 (15.7%) had ASIA C, 21 (19.4%) had ASIA D, and 57 (52.9%) had ASIA E neurology upon admission. The Thoracolumbar Injury Classification and Severity score (p =0.000), CER (p =0.050), and CSAT (p =0.019) were found to be independently associated with neurological deficits on the multivariate analysis. The receiver operating characteristic curves showed that only CER (area under the curve [AUC], 0.926; 95% confidence interval [CI], 0.860-0.968) and CSAT (AUC, 0.963; 95% CI, 0.908-0.990) had good discriminatory ability, with the optimal cutoff of 50% and 65.3 mm2, respectively. CONCLUSIONS: Based on the results, the optimal cutoff values of CER >50% and CSAT >65.3 mm2 can predict the incidence of neurological deficits in LLFs.

Correlation Analysis Between Computed Tomography and Magnetic Resonance Imaging for Assessing Thoracic Pedicle Morphology.

OBJECTIVE: This study aimed to determine the accuracy and reliability of using magnetic resonance imaging (MRI) to characterize thoracic pedicle morphology in the normal population. METHODS: Computed tomography (CT) and MRI datasets of 63 surgically treated patients were included in the study. Bilateral T3, T6, T9, and T12 vertebral levels were evaluated for the type of pedicle, pedicle chord length, and pedicle isthmic diameter on both MRI and CT scans. Pedicles were classified according to Sarwahi et al. into type A (normal pedicle), >4 mm cancellous channel; type B, 2-4 mm channel; type C, completely cortical channels >2 mm; and type D, <2 mm cortical bone channel. RESULTS: Of 504 pedicles, 294 were classified as type A, 173 as type B, 24 as type C, and 13 as type D based on a CT scan. MRI had an overall accuracy rate of 92.86% for detecting type A, 96.53% for type B, and 100% for type C and type D compared with CT scans. Regarding the thoracic levels, MRI had an overall concordance of 97.98% at T3 level, 94.43% at T6 level, 98.11% at T9 level, and 99.3% at T12 level with CT readings. Comparing measurements between MRI and CT studies for pedicle isthmic diameter and pedicle chord length showed moderate to good reliability at all measured levels. CONCLUSIONS: Pedicle measurements obtained by MRI may be used to estimate pedicle dimensions, allowing surgeons to preoperatively determine pedicle screw sizes based on MRI scans alone.

Active tuberculosis of spine: Current updates.

Background: Spinal tuberculosis (TB) is the most common extrapulmonary form of tuberculosis. In both developing and developed countries, TB has been on the rising trend due to factors such as increasing HIV coinfection, multidrug resistance of the organism, and global migration. Spinal TB, which most often affects the lower thoracic and thoracolumbar area, accounts for 50% of all musculoskeletal tuberculosis. Methods: Using the Cochrane Database of Systematic Reviews, EMBASE, and PubMed, a systematic computerized literature search was performed. Analyses of studies published within the past 10 years were conducted. The searches were performed using Medical Subject Headings terms, with "spinal tuberculosis," "diagnosis," "epidemiology," and "etiology","management," "surgery," and "therapy" as subheadings. Results: Progressive collapse, kyphosis, and neurological deficiency are hallmarks of the disease because of its destructive effect on the intervertebral disc and adjacent vertebral bodies. The condition may be identified using laboratory testing and distinctive imaging features, but the gold standard for diagnosis is tissue diagnosis using cultures, histology, and polymerase chain reaction. Uncomplicated spinal TB is today a medical condition that can be adequately treated by multidrug ambulatory chemotherapy. Surgery is reserved for individuals who have instability, neurological impairment, and deformity correction. Debridement, deformity correction, and stable fusion are the cornerstones of surgical treatment. Conclusions: Clinical results for the treatment of spinal TB are generally satisfactory when the disease is identified and treated early. However, the major health issue and the biggest obstacle in achieving the goals of the "End TB strategy" is the recent rise in the emergence of drug resistance. Hence strict vigilance and patient perseverance in the completion of the treatment is the main need of the hour.

Comparison Between Relative Efficacy of Erector Spinae Plane Block and Caudal Epidural Block for Postoperative Analgesia in Lumbar Fusion Surgery- A Prospective Randomized Controlled Study.

STUDY DESIGN: Prospective, randomized controlled double-blinded study. OBJECTIVE: To compare the relative efficacy of ultrasound-guided ESPB and CEB for postoperative analgesia after a single-level lumbar fusion surgery and compared it with conventional multimodal analgesia. METHODS: 81 patients requiring single-level lumbar fusion surgery were randomly allocated into 3 groups (ESPB group, CEB group, and the control group). Demographic and surgical data (blood loss, duration of surgery, perioperative total opioid consumption, muscle relaxants used) were assessed. Postoperatively, the surgical site pain, alertness scale, satisfaction score, time to mobilization, and complications were recorded. RESULTS: The total opioid consumption in the first 24 hours was significantly lower in both the block groups than in the control group (103.70 ± 13.34 vs 105 ± 16.01 vs 142.59 ± 40.91mcg; P < .001). The total muscle relaxant consumption was also significantly less in block groups compared to controls (50.93 ± 1.98 vs 52.04 ± 3.47 vs 55.00 ± 5.29 mg; P < .001). The intraoperative blood loss was significantly less in both the block group (327.78 ± 40.03 mL, 380.74 ± 77.80 mL) than the control group (498.89 ± 71.22 mL) (P < .001). Among the block groups, the immediate postoperative pain relief was better in the CEB group, however, the ESPB group had a longer duration of postoperative pain relief. CONCLUSION: Both ESPB and CEB produce adequate postoperative analgesia after lumbar fusion however the duration of action was significantly longer in the ESPB group with relatively shorter surgical time and lesser blood loss compared to the CEB group.

Giant Anomalous Cervical Spinous Process Causing Dynamic Cord Compression: An Unusual Cause for Myelopathy: A Case Report.

CASE: A 47-year-old male patient presented with progressively worsening gait instability caused by a giant anomalous, free-floating C5 spinous process resulting in dynamic cord compression and myelopathy. The patient was successfully managed with a C5 laminectomy and total excision of the anomalous spinous process with a good functional outcome at the final follow-up. CONCLUSION: Anomalies of the posterior arch of the subaxial cervical spine are relatively uncommon and asymptomatic. This case is being reported for its rarity and to highlight the role of dynamic imaging in patients presenting with congenital anomalies of the cervical spine presenting with compressive myelopathy.

Evaluation of Disc and Endplate Degeneration in AO Type A Fractures Using Magnetic Resonance Imaging Analysis.

OBJECTIVE: Disc degeneration after trauma has been the focus of several investigations, although vertebral endplate changes have received comparatively less attention. The main aim of the present study is to radiologically evaluate the prevalence of the degree of degeneration of the adjacent discs and endplates after AO type A thoracolumbar fractures. METHODS: We retrospectively reviewed 25 patients with an AO type A injury (50 discs and 150 endplates). The type of disc lesion adjacent to the fractured vertebra was classified using the Pfirrmann and Oner classifications immediately after trauma and at the 1-year follow-up. The endplate defects were assessed using the endplate scoring system (total endplate score 1-6) in T1-weighted images. The kyphosis angle and vertebral body height were also measured. RESULTS: The study population consisted of 18 men (72%) and 7 women (28%), with a mean age of 38.9 ± 11.3 years. Overall, 28% of the fractures were type A1, 4% were type A2, 24% were type A3, and 44% were type A4. On statistical analysis, a significant change was found in the degree of degeneration in the cranial adjacent disc using both the Oner (P = 0.004) and Pfirrmann (P = 0.001) classifications at the end of 1 year. The morphological changes at the cranial adjacent discs at 1 year of follow-up showed a strong positive correlation with superior endplate degeneration. CONCLUSIONS: The results from the present study indicate that endplate fractures of vertebrae in patients with thoracolumbar burst fractures can cause disc degeneration, especially at the cranial endplate.

Ralstonia mannitolilytica as a rare cause of spondylodiscitis following endoscopic lumbar discectomy- A report of two cases.

Ralstonia mannitolilytica is a low-virulence, gram-negative bacillus which causes opportunistic infections in immunosuppressed patients. Postoperative spondylodiscitis by R. mannitolilytica has not been reported so far. We report the management of two cases of postoperative spondylodiscitis caused by Ralstonia mannitolilytica presenting to our center within a span of one month following endoscopic lumbar discectomy at a different center. They were managed successfully by surgical debridement and appropriate antibiotics. In these two cases of R.mannitolilytica spondylodiscitis, prompt detection, and intensive treatment resulted in satisfactory outcomes in terms of fulfilling the purpose of the original surgery.

Propensity matched outcome analysis following microdiscectomy versus interlaminar endoscopic discectomy for L5-S1 disc herniation.

Purpose: The main purpose of the study is to perform a propensity-matched functional outcome analysis following microdiscectomy (MD) versus interlaminar endoscopic lumbar discectomy (IELD) for L5-S1 disc herniation. Although many studies have compared endoscopic lumbar discectomy and microdiscectomy, few have compared the outcomes of microdiscectomy (MD) and interlaminar endoscopic discectomy (IELD) at the L5-S1 level. Methods: This is a propensity-matched analysis of 100 patients (50 MD patients, 50 IELD patients) based on baseline covariates with a minimum of one-year follow-up. Patient-reported outcome measures were obtained from EMR during follow-up visits. Back pain and sciatic pain were assessed by the Visual Analogue Scale (VAS-B and VAS-L). Functional outcome was assessed using Oswestry Disability Index (ODI) Score and 12-item Short Form Survey (SF-12) score. Data were obtained at baseline (pre-op) and at 0, 1, 3, and 12 months post-operatively. Results: Mean operative time was significantly lower (p < 0.001) in the IELD group (44 min) compared to the MD group (59 min). Mean VAS-B at the immediate and 1-month postoperative period was significantly (p < 0.001) lower in the IELD group (0.36, 0.24) when compared with the MD group (1.74, 1.16). There was no significant difference between IELD and MD groups with regard to improvement in sciatic pain (VAS-L). ODI scores at 1 month and 3 months post-operative period were significantly (p < 0.001) lower in the IELD group (30.1, 23.2) when compared with the MD group (41, 27.5). However, there was no significant difference between the two groups with regards to VAS-B, ODI, and SF-12 at 1-year follow-up. Conclusion: Our findings indicate that the IELD group achieved better immediate and early postoperative outcomes despite no significant difference at one-year follow-up.

Preoperative pain sensitivity predicts postoperative pain severity and analgesics requirement in lumbar fusion surgery - a prospective observational study.

BACKGROUND CONTENT: The goal of postoperative pain management is to facilitate the patient's return to normal activity and decrease the detrimental effects of acute postsurgical pain. In order to provide more tailored and successful pain treatment, it is necessary to identify individuals who are at a high risk of experiencing severe postoperative pain. The most precise way to assess pain sensitivity is by determining the pressure pain threshold and heat pain threshold by objective methods using a digital algometer and neurotouch respectively. PURPOSE: The primary aim of the study is to assess the preoperative pain threshold and its influence on postoperative pain severity and analgesics requirements in patients undergoing lumbar fusion surgeries. STUDY DESIGN: Prospective, observational study. PATIENT SAMPLE: Sixty patients requiring a single-level lumbar fusion surgery. OUTCOME MEASURES: Postoperative pain intensity and the amount of postoperative analgesics consumption. METHODS: In our patients, preoperative pain sensitivity was assessed by pressure pain threshold measurements with the help of a digital algometer, and heat pain threshold using a neurotouch instrument. In addition, pain sensitivity questionnaires (PSQ) were used in all our patients to determine pain sensitivity. Preoperative psychosocial and functional assessments were performed by Hospital anxiety-depression scores (HADS), and Oswestry disability index (ODI) respectively. Preoperative visual analog scale (VAS) score was determined at three instances of needle prick (phlebotomy, glucometer blood sugar, and intradermal antibiotic test dose) and during the range of movements of the lumbar spine region. Postoperative VAS score and postoperative breakthrough analgesic requirements were recorded in all of these patients from day 0 to day 3. RESULTS: The average age of the patients was 51.11±13.467 years and 70% were females. Females had lower mean algometry values (72.14±7.56) compared to males (77.34±6.33). Patients with higher HADS (p<.0016), higher PSQ (p<.001), higher ODI scores(p<.001), and female gender significantly correlated with a lower algometer average indicating high pain sensitivity. Patients with lower preoperative VAS scores and with higher neurotouch scores showed lower postoperative VAS scores at different time periods. Preoperative VAS scores, algometer average scores, neurotouch scores, and HADS scores were considered as independent variables (predictors) for postoperative VAS at 6 hours period. By the multivariate analysis, factors like preoperative VAS scores, algometer average scores, and HADS scores were statistically significant (p<.05). There was a significant correlation between algometer average scores (p<.001) with the breakthrough analgesics. CONCLUSION: Preoperative assessment of pain sensitivity can predict postoperative analgesic requirements and aid in recovery. Patients with a lower pain threshold should be counseled preoperatively and also receive a better titration of analgesics perioperatively.

Diagnostic Reliability of Computed Tomography in Predicting Posterior Ligamentous Complex Injury in Traumatic Lower Lumbar Fracture.

OBJECTIVE: Though magnetic resonance imaging (MRI) is the primary modality of investigation for determining the extent of PLC injuries in lower lumbar fractures (L3-L5), the reliability of computed tomography (CT) has not been well defined. The main objective of this study is to analyze the diagnostic accuracy of combined CT findings for detecting posterior ligamentous complex injury in patients with lower lumbar fractures. METHODS: We retrospectively analyzed data from 108 patients who presented with traumatic lower lumbar fractures. CT parameters like loss of vertebral body height, local kyphosis, retropulsion of fracture fragment, interlaminar distance (ILD), interspinous distance (ISD), supraspinous distance (SSD), interpedicular distance (IPD), canal compromise, facet joint diastasis in axial images (FJDA) and sagittal images (FJDS), presence of lamina and spinous process fracture were calculated using axial and sagittal CT images. The presence or absence of PLC injury was determined using MRI as a reference standard. RESULTS: Among 108 patients PLC injury was identified in 57 (52.8%). On univariate analysis local kyphosis, retropulsion of fracture fragment, ILD, IPD, FJDS, FJDA, and the presence of spinous process fracture were found to be significant (P < 0.05) in predicting PLC injury. Whereas on multivariate logistic regression analysis, FJDS (P= 0.039), and FJDA (P= 0.003) were found to be variables independently associated with PLC injury. CONCLUSION: Among the various CT parameters, facet joint diastasis (FJDS > 4.2 mm and FJDA > 3.5 mm) is the most reliable factor in determining PLC injury.

Limiting Mrs2-dependent mitochondrial Mg2+ uptake induces metabolic programming in prolonged dietary stress.

The most abundant cellular divalent cations, Mg2+ (mM) and Ca2+ (nM-µM), antagonistically regulate divergent metabolic pathways with several orders of magnitude affinity preference, but the physiological significance of this competition remains elusive. In mice consuming a Western diet, genetic ablation of the mitochondrial Mg2+ channel Mrs2 prevents weight gain, enhances mitochondrial activity, decreases fat accumulation in the liver, and causes prominent browning of white adipose. Mrs2 deficiency restrains citrate efflux from the mitochondria, making it unavailable to support de novo lipogenesis. As citrate is an endogenous Mg2+ chelator, this may represent an adaptive response to a perceived deficit of the cation. Transcriptional profiling of liver and white adipose reveals higher expression of genes involved in glycolysis, ß-oxidation, thermogenesis, and HIF-1α-targets, in Mrs2-/- mice that are further enhanced under Western-diet-associated metabolic stress. Thus, lowering mMg2+ promotes metabolism and dampens diet-induced obesity and metabolic syndrome.