Importance of the lumbar paraspinal muscles on the maintenance of global sagittal alignment after lumbar pedicle subtraction osteotomy.

OBJECTIVE: There are limited data about the influence of the lumbar paraspinal muscles on the maintenance of sagittal alignment after pedicle subtraction osteotomy (PSO) and the risk factors for sagittal realignment failure. The authors aimed to investigate the influence of preoperative lumbar paraspinal muscle quality on the postoperative maintenance of sagittal alignment after lumbar PSO. METHODS: Patients who underwent lumbar PSO with preoperative lumbar MRI and pre- and postoperative whole-spine radiography in the standing position were included. Spinopelvic measurements included pelvic incidence, sacral slope, pelvic tilt, L1-S1 lordosis, T4-12 thoracic kyphosis, spinosacral angle, C7-S1 sagittal vertical axis (SVA), T1 pelvic angle, and mismatch between pelvic incidence and L1-S1 lordosis. Validated custom software was used to calculate the percent fat infiltration (FI) of the psoas major, as well as the erector spinae and multifidus (MF). A multivariable linear mixed model was applied to further examine the association between MF FI and the postoperative progression of SVA over time, accounting for repeated measures over time that were adjusted for age, sex, BMI, and length of follow-up. RESULTS: Seventy-seven patients were recruited. The authors' results demonstrated significant correlations between MF FI and the maintenance of corrected sagittal alignment after PSO. After adjustment for the aforementioned parameters, the model showed that the MF FI was significantly associated with the postoperative progression of positive SVA over time. A 1% increase from the preoperatively assessed total MF FI was correlated with an increase of 0.92 mm in SVA postoperatively (95% CI 0.42-1.41, p < 0.0001). CONCLUSIONS: This study included a large patient cohort with midterm follow-up after PSO and emphasized the importance of the lumbar paraspinal muscles in the maintenance of sagittal alignment correction. Surgeons should assess the quality of the MF preoperatively in patients undergoing PSO to identify patients with severe FI, as they may be at higher risk for sagittal decompensation.

Relationship between facet joint osteoarthritis and lumbar paraspinal muscle atrophy: a cross-sectional study.

OBJECTIVE: The paraspinal muscles play an essential role in the stabilization of the lumbar spine. Lumbar paraspinal muscle atrophy has been linked to chronic back pain and degenerative processes within the spinal motion segment. However, the relationship between the different paraspinal muscle groups and facet joint osteoarthritis (FJOA) has not been fully explored. METHODS: In this cross-sectional study, the authors analyzed adult patients who underwent lumbar spinal surgery between December 2014 and March 2023 for degenerative spinal conditions and had preoperative MRI and CT scans. The fatty infiltration (FI) and functional cross-sectional area (fCSA) of the psoas, erector spinae, and multifidus muscles were assessed on axial T2-weighted MR images at the level of the upper endplate of L4 based on established studies and calculated using custom-made software. Intervertebral disc degeneration at each lumbar level was evaluated using the Pfirrmann grading system. The grades from each level were summed to report the cumulative lumbar Pfirrmann grade. Weishaupt classification (0-3) was used to assess FJOA at all lumbar levels (L1 to S1) on preoperative CT scans. The total lumbar FJOA score was determined by adding the Weishaupt grades of both sides at all 5 levels. Correlation and linear regression analyses were conducted to assess the relationship between FJOA and paraspinal muscle parameters. RESULTS: A total of 225 patients (49.7% female) with a median age of 61 (IQR 54-70) years and a median BMI of 28.3 (IQR 25.1-33.1) kg/m2 were included. After adjustment for age, sex, BMI, and the cumulative lumbar Pfirrmann grade, only multifidus muscle fCSA (estimate -4.69, 95% CI -6.91 to -2.46; p < 0.001) and FI (estimate 0.64, 95% CI 0.33-0.94; p < 0.001) were independently predicted by the total FJOA score. A similar relation was seen with individual Weishaupt grades of each lumbar level after controlling for age, sex, BMI, and the Pfirrmann grade of the corresponding level. CONCLUSIONS: Atrophy of the multifidus muscle is significantly associated with FJOA in the lumbar spine. The absence of such correlation for the erector spinae and psoas muscles highlights the unique link between multifidus muscle quality and the degeneration of the spinal motion segment. Further research is necessary to establish the causal link and the clinical implications of these findings.

Predicting Concrete Strength Early Age using a Combination of Machine Learning and Electromechanical Impedance with Nano-enhanced Sensors.

To ensure the structural integrity of concrete and prevent unanticipated fracturing, real-time monitoring of early-age concrete's strength development is essential, mainly through advanced techniques such as nano-enhanced sensors. The piezoelectric-based electro-mechanical impedance (EMI) method with nano-enhanced sensors is emerging as a practical solution for such monitoring requirements. This study presents a strength estimation method based on Non-Destructive Testing (NDT) Techniques and Long Short-Term Memory (LSTM) and artificial neural networks (ANNs) as hybrid (NDT-LSTMs-ANN), including several types of concrete strength-related agents. Input data includes water-to-cement rate, temperature, curing time, and maturity based on interior temperature, allowing experimentally monitoring the development of concrete strength from the early steps of hydration and casting to the last stages of hardening 28 days after the casting. The study investigated the impact of various factors on concrete strength development, utilizing a cutting-edge approach that combines traditional models with nano-enhanced piezoelectric sensors and NDT-LSTMs-ANN enhanced with nanotechnology. The results demonstrate that the hybrid provides highly accurate concrete strength estimation for construction safety and efficiency. Adopting the piezoelectric-based EMI technique with these advanced sensors offers a viable and effective monitoring solution, presenting a significant leap forward for the construction industry's structural health monitoring practices.

How much improvement in Oswestry Disability Index is Necessary to make your Patient Satisfied after Lumbar Surgery?

STUDY DESIGN: Retrospective review of cohort studies. OBJECTIVE: To clarify the necessary ODI improvement for patient satisfaction two years after lumbar surgery. BACKGROUND: Evaluating elective lumbar surgery care often involves patient-reported outcomes (PRO). While postoperative functional improvement measured by ODI is theoretically linked to satisfaction, conflicting evidence exists regarding this association. METHODS: Baseline ODI and 2-year postoperative ODI were assessed. Patient satisfaction, measured on a scale from 1 to 5, with scores ≥4 considered satisfactory, was evaluated. Patients with incomplete follow-up were excluded. Statistical analyses included Mann-Whitney-U and multivariable logistic regression adjusted for age, sex, and BMI. Receiver operating characteristic (ROC) analysis determined threshold values for ODI improvement and postoperative target ODI indicative of patient satisfaction. RESULTS: 383 patients were included (mean age 65±10 y, 57% female). ODI improvement was observed in 91% of patients, with 77% reporting satisfaction scores ≥4. Baseline ODI (median 62, IQR 46-74) improved to a median of 10 (IQR 1-10) 2 years postoperatively. Baseline (OR 0.98, P=0.015) and postoperative ODI scores (OR 0.93, P<0.001), as well as the difference between them (OR 1.04, P< 0.001), were significantly associated with patient satisfaction. Improvement of ≥38 ODI points or a relative change of ≥66% was indicative for patient satisfaction, with higher sensitivity (80%) and specificity (82%) for the relative change versus the absolute change (69%, 68%). With a sensitivity of 85% and a specificity of 77%, a postoperative target ODI of ≤24 indicated patient satisfaction. CONCLUSION: Lower baseline ODI and greater improvements in postoperative ODI are associated with an increased likelihood of patient satisfaction. A relative improvement of ≥66% or achieving a postoperative ODI score of ≤24 were the most indicative thresholds for predicting patient satisfaction, proving more sensitivity and specificity than an absolute change of ≥38 points.

Evaluation of Peripheral Blood Inflammatory Markers in Patients with Chronic Subdural Hematoma.

BACKGROUND AND AIM: Chronic subdural hematoma (CSH) refers to intracranial hemorrhages frequently caused by minor head trauma and is mostly seen in middle and advanced age. One of the hypotheses regarding the development of CSH is that the inflammatory cascade plays a pivotal role in this process. MATERIALS AND METHODS: The inclusion criteria covered patients in all ages who were diagnosed as CSH by computed tomography and/or magnetic resonance imaging and treated by surgical intervention in our clinic between 2018 and 2020. Patient files were reviewed retrospectively, and medical records of age, gender, trauma history, unilateral or bilateral lesion, and leukocyte, neutrophil, lymphocyte, monocytes, and platelet counts were obtained. Receiver operating characteristic (ROC) analysis was used for the most appropriate neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), and age discrimination in the presence of CSH, and multiple logistic regression analyses were used to determine the effect of independent factors on dependent variables. RESULTS: A total of 68 cases, 57 (83.8%) male and 11 (16.2%) female, aged between 13 and 93, were included in the study. The mean age of the patients included in the study was 72.59 ± 13.13 years. NLR of the cases ranged from 1.37 to 34.18, with a mean of 6.53 ± 6.74 and a median of 3.57. NLR and PLR were found to be statistically significantly higher in CSH patients compared to the healthy control group, and the cut-off values for NLR, PLR, and age were 2.8, 132, and 55, respectively. Age and NLR were found to be independent factors associated with CSH (P < 0.05). CONCLUSION: As seen from the results of this study, peripheral blood values in CSH patients may be significantly higher than in the healthy control group, while they are below the normal laboratory cut-off values.

Abdominal Aortic Calcification is Associated with Degeneration of The Paraspinal Muscles - A Retrospective cross-sectional Study.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To analyze the relationship of abdominal aortic calcification (AAC) and a reduction in the cross-sectional area (CSA) and the fatty infiltration (FI) of the paravertebral muscles in patients undergoing lumbar fusion surgery. BACKGROUND: Both AAC and paraspinal muscle degeneration have been shown to be associated with poorer outcomes after surgical treatment of degenerative diseases of the lumbar spine. However, there is a lack of data on the association between AAC and paraspinal muscle changes in patients undergoing spine surgery. METHODS: We retrospectively analyzed patients undergoing lumbar fusion for degenerative spinal pathologies. Muscular and spinal degeneration were measured on magnetic resonance imaging (MRI). AAC was classified on lateral lumbar radiographs. The association of AAC and paraspinal muscle composition was assessed by a multivariate regression analysis adjusted for age, sex, body mass index (BMI), comorbidities, and lumbar degeneration. RESULTS: A total of 301 patients was included. Patients with AAC showed significantly higher degrees of intervertebral disc and facet joint degeneration as well as higher total endplate scores at the L3/4 level. The univariable regression analysis showed a significant positive correlation between the degree of AAC and the FI of the erector spinae (b=0.530, P<0.001) and multifidus (b=0.730, P<0.001). The multivariable regression analysis showed a significant positive correlation between the degree of AAC and the FI of the erector spinae (b=0.270, P=0.006) and a significant negative correlation between the degree of AAC and the CSA of the psoas muscle (b=-0.260, P=0.003). CONCLUSION: This study demonstrates a significant and independent association between AAC and degeneration of the erector spinae and the psoas muscles in patients undergoing lumbar fusion. As both AAC and degeneration of paraspinal muscles impact postoperative outcomes negatively, preoperative assessment of AAC may aid in identifying patients at higher risk after lumbar surgery.

Importance of the cervical paraspinal muscles in postoperative patient-reported outcomes and maintenance of sagittal alignment after anterior cervical discectomy and fusion.

OBJECTIVE: The aim of this study was to investigate the influence of preoperatively assessed paraspinal muscle parameters on postoperative patient-reported outcomes and maintenance of cervical sagittal alignment after anterior cervical discectomy and fusion (ACDF). METHODS: Patients with preoperative and postoperative standing cervical spine lateral radiographs and preoperative cervical MRI who underwent an ACDF between 2015 and 2018 were reviewed. Muscles from C3 to C7 were segmented into 4 functional groups: anterior, posteromedial, posterolateral, and sternocleidomastoid. The functional cross-sectional area and also the percent fat infiltration (FI) were calculated for all groups. Radiographic alignment parameters collected preoperatively and postoperatively included C2-7 lordosis and C2-7 sagittal vertical axis (SVA). Neck Disability Index (NDI) scores were recorded preoperatively and at 2 and 4-6 months postoperatively. To investigate the relationship between muscle parameters and postoperative changes in sagittal alignment, multivariable linear mixed models were used. Multivariable linear regression models were used to analyze the correlations between the changes in NDI scores and the muscles' FI. RESULTS: A total of 168 patients with NDI and 157 patients with sagittal alignment measurements with a median follow-up of 364 days were reviewed. The mixed models showed that a greater functional cross-sectional area of the posterolateral muscle group at each subaxial level and less FI at C4-6 were significantly associated with less progression of C2-7 SVA over time. Moreover, there was a significant correlation between greater FI of the posteromedial muscle group measured at the C7 level and less NDI improvement at 4-6 months after ACDF. CONCLUSIONS: The findings highlight the importance of preoperative assessment of the cervical paraspinal muscle morphology as a predictor for patient-reported outcomes and maintenance of C2-7 SVA after ACDF.

Asymmetrical atrophy of the paraspinal muscles in patients undergoing unilateral lumbar medial branch radiofrequency neurotomy.

ABSTRACT: Lumbar medial branch radiofrequency neurotomy (RFN), a common treatment for chronic low back pain due to facet joint osteoarthritis (FJOA), may amplify paraspinal muscle atrophy due to denervation. This study aimed to investigate the asymmetry of paraspinal muscle morphology change in patients undergoing unilateral lumbar medial branch RFN. Data from patients who underwent RFN between March 2016 and October 2021 were retrospectively analyzed. Lumbar foramina stenosis (LFS), FJOA, and fatty infiltration (FI) functional cross-sectional area (fCSA) of the paraspinal muscles were assessed on preinterventional and minimum 2-year postinterventional MRI. Wilcoxon signed-rank tests compared measurements between sides. A total of 51 levels of 24 patients were included in the analysis, with 102 sides compared. Baseline MRI measurements did not differ significantly between the RFN side and the contralateral side. The RFN side had a higher increase in multifidus FI (+4.2% [0.3-7.8] vs +2.0% [-2.2 to 6.2], P = 0.005) and a higher decrease in multifidus fCSA (-60.9 mm2 [-116.0 to 10.8] vs -19.6 mm2 [-80.3 to 44.8], P = 0.003) compared with the contralateral side. The change in erector spinae FI and fCSA did not differ between sides. The RFN side had a higher increase in multifidus muscle atrophy compared with the contralateral side. The absence of significant preinterventional degenerative asymmetry and the specificity of the effect to the multifidus muscle suggest a link to RFN. These findings highlight the importance of considering the long-term effects of lumbar medial branch RFN on paraspinal muscle health.

The relationship between paraspinal muscle atrophy and degenerative lumbar spondylolisthesis at the L4/5 level.

BACKGROUND/CONTEXT: Degenerative lumbar spondylolisthesis (DLS) is a prevalent spinal condition that can result in significant disability. DLS is thought to result from a combination of disc and facet joint degeneration, as well as various biological, biomechanical, and behavioral factors. One hypothesis is the progressive degeneration of segmental stabilizers, notably the paraspinal muscles, contributes to a vicious cycle of increasing slippage. PURPOSE: To examine the correlation between paraspinal muscle status on MRI and severity of slippage in patients with symptomatic DLS. STUDY DESIGN/SETTING: Retrospective cross-sectional study at an academic tertiary care center. PATIENT SAMPLE: Patients who underwent surgery for DLS at the L4/5 level between 2016-2018 were included. Those with multilevel DLS or insufficient imaging were excluded. OUTCOME MEASURES: The percentage of relative slippage (RS) at the L4/5 level evaluated on standing lateral radiographs. Muscle morphology measurements including functional cross-sectional area (fCSA), body height normalized functional cross-sectional area (HI) of Psoas, erector spinae (ES) and multifidus muscle (MF) and fatty infiltration (FI) of ES and MF were measured on axial MR. Disc degeneration and facet joint arthritis were classified according to Pfirrmann and Weishaupt, respectively. METHODS: Descriptive and comparative statistics, univariable and multivariable linear regression models were utilized to examine the associations between RS and muscle parameters, adjusting for confounders sex, age, BMI, segmental degeneration, and back pain severity and symptom duration. RESULTS: The study analyzed 138 out of 183 patients screened for eligibility. The median age of all patients was 69.5 years (IQR 62 to 73), average BMI was 29.1 (SD±5.1) and average preoperative ODI was 46.4 (SD±16.3). Patients with Meyerding-Grade 2 (M2, N=25) exhibited higher Pfirrmann scores, lower MFfCSA and MFHI, and lower BMI, but significantly more fatty infiltration in the MF and ES muscles compared to those with Meyerding Grade 1 (M1). Univariable linear regression showed that each cm2 decrease in MFfCSA was associated with a 0.9%-point increase in RS (95% CI -1.4 to - 0.4, p<.001), and each cm2/m2 decrease in MFHI was associated with an increase in slippage by 2.2%-points (95% CI -3.7 to -0.7, p=.004). Each 1%-point rise in ESFI and MFFI corresponded to 0.17%- (95% CI 0.05-0.3, p=.01) and 0.20%-point (95% CI 0.1-0.3 p<.001) increases in relative slippage, respectively. Notably, after adjusting for confounders, each cm2 increase in PsoasfCSA and cm2/m2 in PsoasHI was associated with an increase in relative slippage by 0.3% (95% CI 0.1-0.6, p=.004) and 1.1%-points (95% CI 0.4-1.7, p=.001). While MFfCSA tended to be negatively associated with slippage, this did not reach statistical significance (p=.105). However, each 1%-point increase in MFFI and ESFI corresponded to increases of 0.15% points (95% CI 0.05-0.24, p=.002) and 0.14% points (95% CI 0.01-0.27, p=.03) in relative slippage, respectively. CONCLUSION: This study found a significant association between paraspinal muscle status and severity of slippage in DLS. Whereas higher degeneration of the ES and MF correlate with a higher degree of slippage, the opposite was found for the psoas. These findings suggest that progressive muscular imbalance between posterior and anterior paraspinal muscles could contribute to the progression of slippage in DLS.

Association Between Severity of Cervical Central Spinal Stenosis and Paraspinal Muscle Parameters in Patients Undergoing Anterior Cervical Discectomy and Fusion.

STUDY DESIGN: Retrospective study. OBJECTIVE: The aim of this study was to evaluate the association between severity and level of cervical central stenosis (CCS) and the fat infiltration (FI) of the cervical multifidus/rotatores (MR) at each subaxial levels. SUMMARY OF BACKGROUND DATA: The relationship between cervical musculature morphology and the severity of CCS is poorly understood. METHODS: Patients with preoperative cervical magnetic resonance imaging (MRI) who underwent anterior cervical discectomy and fusion (ACDF) were reviewed. The cervical MR were segmented from C3 to C7 and the percent FI was measured using a custom-written Matlab software. The severity of the CCS at each subaxial level was assessed using a previously published classification. Grade 3, representing a loss of cerebrospinal fluid space and deformation of the spinal cord > 25%, was set as the reference and compared to the other gradings. Multivariable linear regression analyses were conducted and adjusted for age, sex, and body mass index. RESULTS: 156 consecutive patients were recruited. A spinal cord compression at a certain level was significantly associated with a greater FI of the MR below that level. After adjustment for the above-mentioned confounders, our results showed that spinal cord compression at C3/4 and C4/5 was significantly associated with greater FI of the MR from C3 to C6 and C5 to C7, respectively. A spinal cord compression at C5/6 or C6/7 was significantly associated with greater FI of the MR at C7. CONCLUSION: Our results demonstrated significant correlations between the severity of CCS and a greater FI of the MR. Moreover, significant level-specific correlations were found. A significant increase in FI of the MR at the levels below the stenosis was observed in patients presenting with spinal cord compression. Given the segmental innervation of the MR, the increased FI might be attributed to neurogenic atrophy. LEVEL OF EVIDENCE: 3.

Assessing paraspinal muscle atrophy with electrical impedance myography: Limitations and insights.

Paraspinal muscle atrophy is gaining attention in spine surgery due to its link to back pain, spinal degeneration and worse postoperative outcomes. Electrical impedance myography (EIM) is a noninvasive diagnostic tool for muscle quality assessment, primarily utilized for patients with neuromuscular diseases. However, EIM's accuracy for paraspinal muscle assessment remains understudied. In this study, we investigated the correlation between EIM readings and MRI-derived muscle parameters, as well as the influence of dermal and subcutaneous parameters on these readings. We retrospectively analyzed patients with lumbar spinal degeneration who underwent paraspinal EIM assessment between May 2023 to July 2023. Paraspinal muscle fatty infiltration (FI) and functional cross-sectional area (fCSA), as well as the subcutaneous thickness were assessed on MRI scans. Skin ultrasound imaging was assessed for dermal thickness and the echogenicities of the dermal and subcutaneous layers. All measurements were performed on the bilaterally. The correlation between EIM readings were compared with ultrasound and MRI parameters using Spearman's correlation analyses. A total of 20 patients (65.0% female) with a median age of 69.5 years (IQR, 61.3-73.8) were analyzed. The fCSA and FI did not significantly correlate with the EIM readings, regardless of frequency. All EIM readings across frequencies correlated with subcutaneous thickness, echogenicity, or dermal thickness. With the current methodology, paraspinal EIM is not a valid alternative to MRI assessment of muscle quality, as it is strongly influenced by the dermal and subcutaneous layers. Further studies are required for refining the methodology and confirming our results.

Enhancing physical characteristics and antibacterial efficacy of chitosan through investigation of microwave-assisted chemically formulated chitosan-coated ZnO and chitosan/ZnO physical composite.

This study investigates the creation and analysis of chitosan-zinc oxide (CS-ZnO) nanocomposites, exploring their effectiveness in inhibiting bacteria. Two synthesis approaches, physical and chemical, were utilized. The CS-ZnO nanocomposites demonstrated strong antibacterial properties, especially against Staphylococcus aureus, a Gram-positive bacterium. Chemically synthesized nanocomposites (CZ10 and CZ100) exhibited larger inhibition zones (16.4 mm and 18.7 mm) compared to physically prepared CS-Z5 and CS-Z20 (12.2 mm and 13.8 mm) against Staphylococcus aureus. Moreover, CZ nanocomposites displayed enhanced thermal stability, with decomposition temperatures of 281°C and 290°C, surpassing CS-Z5 and CS-Z20 (260°C and 258°C). The residual mass percentages at 800°C were significantly higher for CZ10 and CZ100 (58% and 61%) than for CS-Z5 and CS-Z20 (36% and 34%). UV-Visible spectroscopy revealed reduced band gaps in the CS-ZnO nanocomposites, indicating improved light absorption. Transmission electron microscopy (TEM) confirmed uniform dispersion of ZnO nanoparticles within the chitosan matrix. In conclusion, this research underscores the impressive antimicrobial potential of CS-ZnO nanocomposites, especially against Gram-positive bacteria, and highlights their enhanced thermal stability. These findings hold promise for diverse applications in industries such as medicine, pharmaceuticals, and materials science, contributing to the development of sustainable materials with robust antimicrobial properties.

Nano-Sized Al2O3-Gr Reinforced Al7075 Hybrid Composite: Impact of Cooling Agents on Mechanical, Wear, and Fracture Behavior.

Aluminum metal cast composites (AMCCs) are frequently used in high-tech sectors such as automobiles, aerospace, biomedical, electronics, and others to fabricate precise and especially responsible parts. The mechanical and wear behavior of the metal matrix composites (MMCs) is anticipated to be influenced by the cooling agent's action and the cooling temperature. This research paper presents the findings of a series of tests to investigate the mechanical, wear, and fracture behavior of hybrid MMCs made of Al7075 reinforced by varying wt % of nano-sized Al2O3 and Gr and quenched with water and ice cubes. The heat-treated Al7075 alloy hybrid composites were evaluated for their hardness, tensile, and wear behavior, showcasing a significant process innovation. The heat treatment process greatly improved the hybrid composites' mechanical and wear performance. The samples quenched in ice attained the highest hardness of 119 VHN. There is a 45.37% improvement in the hardness of base alloy with the addition of 3% of Al2O3 and 1% of graphite particles. Further, the highest tensile and compression strengths were found in the ice-quenched 3% Al2O3 and 1% graphite hybrid composites with improvements of 34.2 and 48.83%, respectively, compared to the water-quenched base alloy. Under the samples quenched in ice, the mechanical and wear behavior improved. The tensile fractured surface showed voids, particle pullouts, and dimples. The worn-out surface of wear test samples of the created hybrid composite had micro pits, delamination layers, and microcracks.

Insight into antioxidant and anti-inflammatory effects of marine bacterial natural exopolysaccharide (EPSSM) using carrageenan-induced paw edema in rats.

Inflammation is a part of the body's intricate biological reaction to noxious stimuli and defensive reactions. So, the aim of this investigation was to study the anti-inflammatory activity of exopolysaccharide (EPSSM) using carrageenan-induced paw edema in rats. A halophilic bacterial strain was isolated from marine sediments in the Red Sea in Egypt. The isolate has been visually and physiologically recognized, as well as by analyzing its 16S rRNA gene, which confirms Kocuria sp. clone Asker4. This particular isolate can be referenced using the accession number OL798051.1. EPSSM was subjected to purification and fractionation by a DEAE-cellulose column. Preliminary chemical analysis of EPSSM indicated that the monosaccharides were fructose, glucuronic acid, and xylose, with 2.0, 0.5, and 1.0, respectively. The antioxidant potential of EPSSM was investigated, and it was discovered that the level of activity increased independently of the concentrations, reaching a maximum threshold of 94.13% at 100 µg/mL of EPSSM for 120 min. Also, EPSSM at 50 mg/kg orally produced a significant anti-inflammatory effect on the carrageenan model at 2, 3, and 4 intervals. The EPSSM intervention resulted in reductions in the levels of catalase and superoxide dismutase enzymes, as well as a decrease in glutathione. Furthermore, the levels of nitric oxide, lipid peroxidation, and reactive oxygen species resulting from carrageenan-induced edema showed a significant reduction subsequent to the administration of EPSSM. Moreover, the findings indicated that the protein expression levels of cyclooxygenase-2 and interleukin-6 were reduced following treatment with EPSSM, resulting in a reduction of paw edema.

Spine-specific sarcopenia: distinguishing paraspinal muscle atrophy from generalized sarcopenia.

BACKGROUND CONTEXT: Atrophy of the paraspinal musculature (PM) as well as generalized sarcopenia are increasingly reported as important parameters for clinical outcomes in the field of spine surgery. Despite growing awareness and potential similarities between both conditions, the relationship between "generalized" and "spine-specific" sarcopenia is unclear. PURPOSE: To investigate the association between generalized and spine-specific sarcopenia. STUDY DESIGN: Retrospective cross-sectional study. PATIENT SAMPLE: Patients undergoing lumbar spinal fusion surgery for degenerative spinal pathologies. OUTCOME MEASURES: Generalized sarcopenia was evaluated with the short physical performance battery (SPPB), grip strength, and the psoas index, while spine-specific sarcopenia was evaluated by measuring fatty infiltration (FI) of the PM. METHODS: We used custom software written in MATLAB® to calculate the FI of the PM. The correlation between FI of the PM and assessments of generalized sarcopenia was calculated using Spearman's rank correlation coefficient (rho). The strength of the correlation was evaluated according to established cut-offs: negligible: 0-0.3, low: 0.3-0.5, moderate: 0.5-0.7, high: 0.7-0.9, and very high≥0.9. In a Receiver Operating Characteristics (ROC) analysis, the Area Under the Curve (AUC) of sarcopenia assessments to predict severe multifidus atrophy (FI≥50%) was calculated. In a secondary analysis, factors associated with severe multifidus atrophy in non-sarcopenic patients were analyzed. RESULTS: A total of 125 (43% female) patients, with a median age of 63 (IQR 55-73) were included. The most common surgical indication was lumbar spinal stenosis (79.5%). The median FI of the multifidus was 45.5% (IQR 35.6-55.2). Grip strength demonstrated the highest correlation with FI of the multifidus and erector spinae (rho=-0.43 and -0.32, p<.001); the other correlations were significant (p<.05) but lower in strength. In the AUC analysis, the AUC was 0.61 for the SPPB, 0.71 for grip strength, and 0.72 for the psoas index. The latter two were worse in female patients, with an AUC of 0.48 and 0.49. Facet joint arthropathy (OR: 1.26, 95% CI: 1.11-1.47, p=.001) and foraminal stenosis (OR: 1.54, 95% CI: 1.10-2.23, p=.015) were independently associated with severe multifidus atrophy in our secondary analysis. CONCLUSION: Our study demonstrates a low correlation between generalized and spine-specific sarcopenia. These findings highlight the risk of misdiagnosis when relying on screening tools for general sarcopenia and suggest that general and spine-specific sarcopenia may have distinct etiologies.

Abdominal aortic calcification is an independent predictor of perioperative blood loss in posterior spinal fusion surgery.

OBJECTIVE: Abdominal aortic calcification (AAC), often found incidentally on lateral lumbar radiographs, is increasingly recognized for its association with adverse outcomes in spine surgery. As a marker of advanced atherosclerosis affecting cardiovascular dynamics, this study evaluates AAC's impact on perioperative blood loss in posterior spinal fusion (PSF). METHODS: Patients undergoing PSF from March 2016 to July 2023 were included. Estimated blood loss (EBL) and total blood volume (TBV) were calculated. AAC was assessed on lateral lumbar radiographs according to the Kauppila classification. Predictors of the EBL-to-TBV ratio (%EBL/TBV) were examined via univariable and multivariable regression analyses, which adjusted for parameters such as hypertension and aspirin use. RESULTS: A total of 199 patients (47.2% female) were analyzed. AAC was present in 106 patients (53.3%). AAC independently predicted %EBL/TBV, accounting for an increase in blood loss of 4.46% of TBV (95% CI 1.17-7.74, p = 0.008). CONCLUSIONS: This is the first study to identify AAC as an independent predictor of perioperative blood loss in PSF. In addition to its link to degenerative spinal conditions and adverse postoperative outcomes, the relationship between AAC and increased blood loss warrants attention in patients undergoing PSF.

Cross-Cultural Validation of the Arabic Short-Form McGill Pain Questionnaire (SF-MPQ): Libyan Version in Patients With Musculoskeletal Pain.

Background: The Short-form McGill Pain Questionnaire (SF-MPQ) is a widely used tool for assessing musculoskeletal pain, both in research and clinical practice. However, a culturally appropriate Arabic version for the Libyan context has not been available. This study aims to translate the SF-MPQ, and to examine its reliability and validity for assessing musculoskeletal pain in Libya. Methods: The SF-MPQ was cross-culturally adapted into Arabic using a forward-backward method. A total of 151 patients (Mean age ± SD = 40.66 ± 14) with musculoskeletal pain completed the SF-MPQ and other measures. Of these, 148 patients completed the second round of questionnaire completion two days after the first visit. The intraclass correlation coefficient (ICC) was used to examine relative test-retest reliability and Bland-Altman plots was performed to examine absolute agreement between the two assessments. Spearman's correlation was applied to assess construct validity. Results: The Arabic translation of the SF-MPQ was linguistically equivalent, without significant discrepancies. All but two of the Arabic descriptors were used by more than 33% of the participants, indicating good item measurement equivalency. The results showed a satisfactory Cronbach's α (0.74 for the total score), which indicates good internal consistency. The ICC for the total score revealed a high correlation for the test-retest (0.91), suggesting excellent relative reliability. Bland-Altman analyses showed no significant systematic bias between the repeated measurements. There were positive statistically significant correlations among the SF-MPQ, the Visual Analog Scale, and the Fatigue Severity Scale (P < 0.001), demonstrating good construct validity. Conclusion: These results suggest that the Arabic SF-MPQ is reliable, valid, and cross-culturally equivalent to the original SF-MPQ for evaluating musculoskeletal pain among Arabic-speaking patients in Libya. Clinicians and researchers may therefore consider using this scale, as it is easy to use and understand by different age groups. Further research is needed to confirm our findings and to test the developed Arabic version of the SF-MPQ on different patient populations.

Association between lumbar intervertebral vacuum phenomenon severity and posterior paraspinal muscle atrophy in patients undergoing spine surgery.

PURPOSE: Intervertebral vacuum phenomenon (IVP) and paraspinal muscular atrophy are age-related changes in the lumbar spine. The relationship between both parameters has not been investigated. We aimed to analyze the correlation between IVP and paraspinal muscular atrophy in addition to describing the lumbar vacuum severity (LVS) scale, a new parameter to estimate lumbar degeneration. METHODS: We analyzed patients undergoing spine surgery between 2014 and 2016. IVP severity was assessed utilizing CT scans. The combination of vacuum severity on each lumbar level was used to define the LVS scale, which was classified into mild, moderate and severe. MRIs were used to evaluate paraspinal muscular fatty infiltration of the multifidus and erector spinae. The association of fatty infiltration with the severity of IVP at each lumbar level was assessed with a univariable and multivariable ordinal regression model. RESULTS: Two hundred and sixty-seven patients were included in our study (128 females and 139 males) with a mean age of 62.6 years (55.1-71.2). Multivariate analysis adjusted for age, BMI and sex showed positive correlations between LVS-scale severity and fatty infiltration in the multifidus and erector spinae, whereas no correlation was observed in the psoas muscle. CONCLUSION: IVP severity is positively correlated with paraspinal muscular fatty infiltration. This correlation was stronger for the multifidus than the erector spinae. No correlations were observed in the psoas muscle. The lumbar vacuum severity scale was significantly correlated with advanced disc degeneration with vacuum phenomenon.

Molecular Beamforming for Actuation in Molecular Communication Networks.

The actuation accuracy of sensing tasks performed by molecular communication (MC) schemes is a very important metric. Reducing the effect of sensors fallibility can be achieved by improvements and advancements in the sensor and communication networks design. Inspired by the technique of beamforming used extensively in radio frequency communication systems, a novel molecular beamforming design is proposed in this paper. This design can find application in tasks related to actuation of nano machines in MC networks. The main idea behind the proposed scheme is that the utilization of more sensing nano machines in a network can increase the overall accuracy of that network. In other words, the probability of an actuation error reduces as the number of sensors that collectively take the actuation decision increases. In order to achieve this, several design procedures are proposed. Three different scenarios for the observation of the actuation error are investigated. For each case, the analytical background is provided and compared with the results obtained by computer simulations. The improvement in the actuation accuracy by means of molecular beamforming is verified for a uniform linear array as well as for a random topology.

Decision-making Algorithm for the Surgical Treatment of Degenerative Lumbar Spondylolisthesis of L4/L5.

STUDY DESIGN: A retrospective analysis of prospectively collected data. OBJECTIVE: To report the decision-making process for decompression alone (DA) and decompression and fusion (DF) at a tertiary orthopedic center and compare the operative outcomes between both groups. BACKGROUND: Controversy exists around the optimal operative treatment for DLS, either with DF or DA. Although previous studies tried to establish specific indications, clinical decision-making algorithms are needed. MATERIALS AND METHODS: Patients undergoing spinal surgery for DLS at L4/5 were retrospectively analyzed. A survey of spine surgeons was performed to identify factors influencing surgical decision-making, and their association with the surgical procedure was tested in the clinical data set. We then developed a clinical score based on the statistical analysis and survey results. The predictive capability of the score was tested in the clinical data set with a receiver operating characteristic (ROC) analysis. To evaluate the clinical outcome, two years follow-up postoperative Oswestry Disability Index (ODI), postoperative low back pain (LBP) (Numeric Analog Scale), and patient satisfaction were compared between the DF and DA groups. RESULTS: A total of 124 patients were included in the analysis; 66 received DF (53.2%) and 58 DA (46.8%). Both groups showed no significant differences in postoperative ODI, LBP, or satisfaction. The degree of spondylolisthesis, facet joint diastasis and effusion, sagittal disbalance, and severity of LBP were identified as the most important factors for deciding on DA or DF. The area under the curve of the decision-making score was 0.84. At a cutoff of three points indicating DF, the accuracy was 80.6%. CONCLUSIONS: The two-year follow-up data showed that both groups showed similar improvement in ODI after both procedures, validating the respective decision. The developed score shows excellent predictive capabilities for the decision processes of different spine surgeons at a single tertiary center and highlights relevant clinical and radiographic parameters. Further studies are needed to assess the external applicability of these findings.