Anatomical Compartments Research Articles

Comparison of intracompartment pressure changes in tibial plateau fractures and controlled people: A pilot study.

Acute compartment syndrome (ACS) is a serious medical condition that can be encountered in tibial plateau fractures. However, no studies of compartment pressure changes in patients with tibial plateau fractures compared to patient without fractures have been reported. To obtain a comprehensive understanding of the pressure changes in patients with fractures, we monitored and recorded the compartment pressure and attempted to reveal the potential pressure release function of the human fascia. Cohorts of 43 normal individuals and 23 patients (initial 33, 10 were excluded due to inclusion criteria) and include the number of patients who completed the study with closed tibial fractures (the fracture group, FG, which comprised 6 men and 17 women) were included in this retrospective research. Compartment pressures were measured with Icare, a device that is traditionally used to measure intraocular pressure. Results of measurements at 6 different locations in the lower limb were recorded and compared for three days (days 2, 3, and 4 post fracture) between normal cohort (CG) and fracture cohort (FG) patients. The compartment pressures were comparable at each pressure measurement site (upper, middle and lower) in patients of the CG and the FG. Compared with the CG patients, there was a significant increase in compartment pressure at the upper lateral location in 18-45-year-old patients in the FG (P = 0.013) and at the upper lateral (P = 0.004) and medial locations (P = 0.005) in 46-69-year-old patients, and the values tended to normalize over time. Compared with the contralateral normal limb of patients in the FG, there was a significant increase in compartment pressure at the upper lateral location in 18-45-year-old patients (P = 0.009) and at the upper lateral (P = 0.015) and medial locations (P = 0.016) in 46-69-year-old patients on the fractured side. Based on different fracture classifications, there were no significant differences in compartment pressure at the medial (upper, middle and lower) locations when compared with pressures at the corresponding lateral sites of measurement. The results of this study revealed that the fascial compartment as a whole can release the increased intracompartment pressure after fracture to prevent complications such as acute compartment syndrome caused by a continued increase in pressure. The Icare as a portable device, is potentially useful in compartmental pressure measurement especially in emergency room.

ANALYSIS-ASSOCIATED FACTORS INTERFERING WITH DIFFUSION TENSOR INDICES OF PERIPHERAL NERVES

Diffusion tensor imaging (DTI) enables a non-invasive assessment of tissue architecture based on water diffusion. Advancements in technology have expanded the application of DTI from the central nervous system to the peripheral nervous system. High-resolution magnetic resonance imaging (MRI) systems have further enhanced the visualization of nerve compartments. This study investigates the influence of region of interest (ROI) selection on DTI indices in ex vivoperipheral nerves. Cadaveric median nerves (n=10) were harvested and immersed in fluorinated-carbon liquid, and 9-mm segments were independently scanned with a 9.4-T MRI system (scanning time 40 h). Diffusion-weighted signals were summed, and diffusion tensors were calculated for anatomical compartments using different delineation techniques. Following the initial scan, five samples were scanned for the second time using an identical protocol. The analysis showed that the inclusion of an inert background into the ROI significantly reduces fractional anisotropy (FA). Significant differences in diffusion tensors were observed between the initial and intermediate nerve portions, with FA and mean diffusivity (MD) differing by as much as 25.2% and 25.6%, respectively. Tracing the fascicles without the interfascicular epineurium exhibited an 8.8% lower FA compared to the delineations of the epineurium. Second MRI scans showed significant changes in diffusion tensors with higher eigenvalues D1-D3 and MD. In conclusion, the intermediate portions of the nerve demonstrated greater consistency in DTI indices and are therefore recommended for analysis over the initial portions. Using an inert liquid can minimize background effects, but the inherent diffusion properties of the tissue must be carefully considered. Prolonged scanning times can alter diffusion tensors, likely due to autolytic processes, underscoring the importance of consistent pre-scanning conditions and acquisition protocols. Additionally, maintaining consistency in delineations is paramount, regardless of whether the tracing method includes or excludes the interfascicular epineurium.

Is the phoenix sign phenomenon due to vasodilation? A double-blinded, randomized controlled trial comparing motor function recovery after diagnostic common fibular nerve block with lidocaine and papaverine

BackgroundFocal entrapment of the common fibular (peroneal) nerve (CFN) is the most common nerve entrapment in the lower extremity. Accurate diagnosis can be difficult due to co-existent pathology such as low back pathology. A 1% lidocaine block of CFN is often used to confirm the local entrapment pathology and demonstrate possibility of pain relief. A surprising, unexpected and temporary strengthening of CFN supplied ankle and foot muscles is occasionally produced, termed the Phoenix sign. Aetiology of this phenomenon has been puzzling, but restoration of neural circulation and nutrition via improved local blood flow has been postulated to be responsible.MethodsThis is a double-blinded, randomized, prospective controlled trial of 20 patients, comparing 2 vasodilating agents and their ability to produce the Phoenix effect. Ultrasound guided infiltration of 0.3 mL 1% lidocaine or papaverine HCl 10 mg/mL was executed adjacent to CFN. Motor strength pre- infiltration and 4 min post-infiltration were measured for anterior compartment muscles utilizing MRC manual motor testing reported on a 0–5 scale. The extensor hallucis longus (EHL) muscle proved to be the most significant.ResultsAverage motor strength of the EHL improved from 2.2 (+/-0.40) to 4.9 (+/-0.32).) in the lidocaine group. In the papaverine group, pre-infiltration EHL motor strength averaging 2.1 (+/-0.93) improved to 4.4 (+/- 1.01) post-infiltration. Papaverine and lidocaine produced similar statistically significant increases in muscle strength (p = < 0.05).ConclusionThere was no difference between small local infiltrations of lidocaine or papaverine in production of increased anterior compartment EHL motor strength. It is most likely that the Phoenix Effect is explained by temporary local improvements in the microcirculation of the CFN vasa nervorum.Trial RegistrationNCT06637046 10/10/2024 Retrospectively registered.

Cortical, striatal, and thalamic populations self-organize into a functionally connected circuit with long-term memory properties

The human brain is a complex organ with an intricate neuronal connectivity and diverse functional regions. Neurological disorders often disrupt the delicate balance among these anatomical compartments, resulting in severe impairments. The available therapeutic options constitute an incomplete solution as many patients respond partially, highlighting the need for continued research into causes and treatments. Bottom-up approaches, like in vitro models, offer insights into brain functions as they recreate the in vivo microenvironment that allows studying how specific features affect physiological and pathological conditions. In this work, we engineered the cortical-striatal-thalamic (CST) circuit, involved in many brain functions such as action initiation and selection, using a three-compartment polymeric device. We characterized the emerging spontaneous electrophysiological activity by using Micro-Electrode Arrays (MEAs). Cortical neurons exhibited complex bursting activity, which influenced the entire circuit. Striatal and thalamic neurons displayed predominantly tonic firing when isolated, while interconnections with the cortex synchronized and organized their neuronal activity, highlighting the cortical pivotal role in bursting activity and information processing. The CST circuit demonstrated self-organization abilities and displayed high entropy values, indicative of dynamic richness and information encoding potential. Furthermore, we proved the CST’s involvement in learning and memory. Our CST model provides a platform for further exploration into brain circuitry and potential therapeutic interventions, underscoring the necessity of realistic in vitro models to fully understand neurological diseases' pathophysiology.

Anatomy-guided resections for paralimbic tumors in the temporo-insular region: combining tumor and epilepsy surgery concepts.

Tumors in the temporo-mesial region often extend into the insula and vice versa. The present study investigated the results of a surgical strategy that combines principles of tumor and epilepsy surgery. We retrospectively analyzed 157 consecutive patients with intrinsic brain tumors in the temporo-mesial region, with varying degrees of extensions into the insula (44 patients, 28.0%). The surgical strategy utilized "anatomy-guided resection," targeting specific anatomical compartments infiltrated by the tumor (e.g., temporal pole, anterior temporo-mesial region = uncus and hippocampal head, posterior temporo-mesial, insula) rather than treating the tumor as a single mass. The most frequent histologies were ganglioglioma CNS WHO grade 1 (55 patients, 35.0%) and IDH1 wildtype glioblastoma (36 patients, 22.9%). Tumor infiltration was most commonly found in the anterior temporo-mesial compartment (145 patients, 92.4%). An anterior temporal lobectomy was part of the surgical strategy in 131 cases (83.4%). Seventy-six patients (48.4%) with drug-resistant epilepsy underwent a formal presurgical epilepsy work-up, including depth electrode placement in three cases. Complete resections were achieved in 117 patients (74.5%), with supramarginal resections performed in 89 cases (56.7%). Four patients experienced non-temporary neurological complications (CTCAE grade 3-5). At 6 months, 127 of 147 assessable patients (86.4%) were free from seizures or auras (ILAE class 1), excluding early postoperative seizures (<30 days). At 24 months, 122 of 144 assessable cases (84.7%) remained seizure-free (ILAE class 1). Kaplan-Meier estimates for 5-year overall survival were 98.5% for non-recurrent glioneuronal tumors. The 2-year overall survival estimates were 96.0% for 24 primary diffuse CNS WHO grade 2 and 3 gliomas and 55.2% for 30 patients undergoing first surgeries for glioblastomas/astrocytomas CNS WHO grade 4. Combining both epilepsy and tumor surgery concepts in the surgical treatment of intrinsic brain tumors involving the mesial temporal lobe, often extending into the insula, led to more extensive resections, improved seizure outcomes, and potentially even better patient survival outcomes.

Embryo-restricted responses to maternal IL-17A promote neurodevelopmental disorders in mouse offspring.

Prenatal imprinting to interleukin 17A (IL-17A) triggers behavioral disorders in offspring. However, reported models of maternal immune activation utilizing immunostimulants, lack specificity to elucidate the anatomical compartments of IL-17A's action and the distinct behavioral disturbances it causes. By combining transgenic IL-17A overexpression with maternal deficiency in its receptor, we established a novel model of prenatal imprinting to maternal IL-17A (acronym: PRIMA-17 model). This model allowed us to study prenatal imprinting established exclusively through embryo-restricted IL-17A responses. We demonstrated a transfer of transgenic IL-17A across the placental barrier, which triggered the development of selected behavioral deficits in mouse offspring. More specifically, embryonic responses to IL-17A resulted in communicative impairment in early-life measured by reduced numbers of nest retrieval calls. In adulthood, IL-17A-imprinted offspring displayed an increase in anxiety-like behavior. We advocate our PRIMA-17 model as a useful tool to study neurological deficits in mice.

Porcine blast injury model achieves prolonged elevation of intra-compartmental pressures without exogenous pressure manipulation

BackgroundMost existing animal models of acute compartment syndrome (ACS) rely on exogenous manipulation of intra-compartmental pressures to model ACS. The purpose of the current study was to evaluate the endogenous effect of a blast injury on porcine lower leg intra-compartmental pressures (ICP).MethodsThe hindlimb of juvenile Landrace pigs was fractured at the diaphyseal tibia and subjected to blasts of compressed air to mimic a blast injury. Injured and control legs underwent pre-operative continuous ICP monitoring. At 4.5 h post injury, the fracture was stabilized followed by closure of the anterior compartment fascia (continued compartment pressure model, CCPM) or four compartment fasciotomy. Pressure measurements were made after operative fixation. Select pigs in CCPM were harvested between 48 and 72 h post-injury to evaluate the duration of ICP elevation.ResultsPost-injury, the model created significantly elevated ICP compared to control limbs (54.5 ± 18.2 vs. 18.2 ± 4.9 mmHg; p < 0.001). Operative fixation and anterior compartment fascial closure further increased the ICP (Mean: 87.4 ± 42.5 mmHg) relative to the pre-operative state (p = 0.037). Fasciotomy returned baseline compartment pressures (Mean: 13.7 ± 10.2 mmHg) which were equivalent to control limbs (p = 0.117). Pressure measurements at the time of delayed harvest (48–72 h) demonstrated that elevated ICP persisted following injury (69.7 ± 55.12 mmHg).ConclusionThe current study demonstrates that a pilot porcine blast model elevates ICP comparable to existing animal models of compartment syndrome without exogenous ICP manipulation. ICP remained elevated at 48–72 h in the absence of fasciotomy.

Practical Approach to Orbital Lesions by Anatomic Compartments.

A wide range of pathologic conditions can originate in the orbit. While it is common to approach the differential diagnosis based on disease categories, such as neoplastic and inflammatory, segmenting the orbit into anatomic compartments can direct the radiologist toward the most common pathologic conditions for each manifestation and space. The orbit can be divided into intraconal, conal, and extraconal compartments. Additionally, the optic nerve sheath complex and lacrimal apparatus can be partitioned into separate compartments due to their unique functions and pathologic features. By using this anatomic approach, the authors review the most common pathologic conditions affecting the orbit and discuss clinical and imaging findings that can guide the differential diagnosis for lesions with similar appearances. Published under a CC BY 4.0 license. Supplemental material is available for this article.

Expression of Wnt signaling proteins in rare congenital bladder disorders

Introduction and AimsCongenital bladder anomalies are rare and are a leading cause of end stage renal failure in children. The Wnt signaling pathway, important during embryonic development, has been implicated in the pathogenesis of these conditions through regulation of gene expression, including essential transcription factors. We investigated the expression of four Wnt transcriptional targets, namely, Pygopus 1 (Pygo1), FRA1, TCF7L1 and Connexin 43 (Cx43) in three rare congenital bladder disorders: bladder exstrophy (BE), neurogenic bladder (NGB) and posterior urethral valves (PUV). MethodsBladder tissue samples were collected from patients at the Great Ormond Street Hospital for Sick Children, London, UK, with control (normally-functioning bladder, N=9), BE (N=15), NGB (N=6) and PUV (N=5). Histological analysis was performed using the van Gieson stain to differentiate smooth muscle (SM) and connective tissue (CT) compartments. An unbiased, automated, semi-quantitative immunofluorescence analysis was performed to measure the labelling intensity of four Wnt-related proteins in tissue from these four groups. Results and DiscussionThere was a significant (p<0.05) increase in the expression of Pygo1 in the smooth muscle of all anomalies examined and also in the connective tissue in PUV compared to control. Cx43 also showed overexpression in the smooth muscle across all conditions; however, there was a reduced expression in NGB and an increase in PUV in connective tissue. TCF7L1 showed a significant decrease in both tissue compartments for NGB, whereas FRA1 expression remained unchanged across all anomalies. We also measured colocalization of Wnt-related proteins. TCF7L1 exhibited increased colocalization with Pygo1 and FRA1 in exstrophy compared to control. These results suggest a complex dysregulation of the Wnt pathway in congenital bladder disorders. ConclusionWnt signaling-related proteins show dysregulation in congenital bladder disorders compared to control tissue. Understanding these mechanisms should help towards non-invasive early diagnosis, drug target discovery and development of treatment strategies for these conditions.Summary tableSummary of Wnt-related protein expression and colocalization in bladder exstrophy (BE), neurogenic bladder (NGB) and posterior urethral valves (PUV) disorder compared to normally-functioning control bladder. The table shows the levels of expression as significantly up (↑) down (↓) or no change (-) of Pygopus 1 (Pygo1), Connexin 43 (Cx43), FRA1 and TCF7L1 expression in smooth muscle and connective tissue compartments in BE, NGB and PUV relative to control bladder tissue samples. The table also shows colocalization of six protein pairs of Pygo1 and FRA1; Pygo1 and Cx43; Pygo1 and TCF7L1; FRA1 and Cx43; FRA1 and TCF7L1 and Cx43 and TCF7L1 in bladder disorders compared to control.Summary tableProtein Expression (Smooth muscle)Pygo1Cx43FRA1TCF7L1BE↑↑--NGB↑↑-↓PUV↑↑--Protein Expression (Connective tissue)BE----NGB-↓-↓PUV↑↑--ColocalizationPygo1/FRA1Pygo1/Cx43Pygo1/TCF7L1FRA1/Cx43FRA1/TCF7L1Cx43/TCF7L1Exstrophy--↑-↑-NGB------PUV------

Use of multiparametric MRI to noninvasively assess iodinated contrast-induced acute kidney injury

PurposeTo gauge the utility of multiparametric MRI in characterizing pathologic changes after iodinated contrast-induced acute kidney injury (CI-AKI) in rats. MethodsWe randomly grouped 24 rats injected with 8 g iodine/kg of body weight (n = 6 each) and 6 rats injected with saline as controls. All rats underwent T1, T2 mapping and diffusion kurtosis imaging (DKI) after contrast injection at 0 (control), 1, 3, 7, 13 days. T1, T2, and mean kurtosis (MK) values were performed in renal outer/inner stripes of outer medulla (OSOM and ISOM) and cortex (CO), and their diagnosis performance for CI-AKI also been evaluated. Serum creatinine (SCr), insulin-like growth factor-binding protein 7 (IGFBP7), tissue inhibitor metalloproteinase 2 (TIMP-2), aquaporin-1 (AQP1), α-smooth muscle actin (α-SMA), and histologic indices were examined. ResultsCompared with controls, urinary concentrations of both TIMP-2 and IGFBP7 were obviously elevated from Day 1 to Day 13 (all p < 0.05). T2 values were significantly higher than control group for Days 1 and 3, and T1 and MK increased were more remarkable at all time points (Days 1–13) in CI-AKI (all p < 0.05) than control group. Changes in T1 and MK strongly correlated with renal injury scores of all anatomical compartments and with expression levels of AQP1 and moderately correlated with α-SMA. Changes in T2 values correlating moderately with renal scores of CO, ISOM and OSOM and AQP1. The MK obtained the highest area under the receiver operating characteristic (ROC) curve of 0.846 with a sensitivity of 70.8 % and specificity of 88.9 %. ConclusionsCombined use of multiparametric MRI could be a valid noninvasive method for comprehensive monitoring of CI-AKI. Among these parameters, MK may achieve the best diagnostic performance for CI-AKI.

Evaluating the Role of Rectus Abdominis Fat Transfer (RAFT) in Improving Muscle Thickness: Does it Really Work? A 12-Month Follow-Up Cohort Study.

Looking for an adequate solution for those patients who desire abdominal definition, but are not candidates for liposuction alone, Danilla developed a technique, using selective fat grafting into the rectus abdominis (RAFT) to increase the muscle volume in addition to selective liposuction and abdominoplasty to provide an optimal body contouring. To determine whether intramuscular fat grafting in the rectus abdominis muscles leads to an increase in muscle thickness after one year. This is a prospective cohort study, from a single center, carried out over 24 months (October 2021-September 2023). Sixty-two patients who underwent lipoabdominoplasty and RAFT, had their rectus abdominis cross section measured by ultrasound pre- and 12 months postoperatively. To compare the muscle thickness, a paired t-test statistic was used. A p-value of 0.05 was considered statistically significant (IBM SPSS Statistics V26). After 1 year, all 62 patients showed an increase in the size of the rectus muscle cross section, although only 58 (94%) had fat identifiable in the US. Preoperatively, the mean muscle cross-sectional size was 1, 4cm. After RAFT, overall mean muscle cross section was 2, 3cm (0, 9cm/66.9% increase). When stratified into groups with and without identifiable fat, the group in which the graft remained showed greater increase than the group with no visible fat (69, 9% vs 19,6%). The RAFT provided a significant increase in the muscle cross section in most cases after 1 year. The presence of fat is related to a statistically significant increase in the muscle compartment (pack). This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Influence of muscle packing on the three-dimensional architecture of rabbit M. plantaris

In their physiological condition, muscles are surrounded by connective tissue, other muscles and bone. These tissues exert transverse forces that change the three-dimensional shape of the muscle compared to its isolated condition, in which all surrounding tissues are removed. A change in shape affects the architecture of a muscle and therefore its mechanical properties. The rabbit M. plantaris is a multi-pennate calf muscle consisting of two compartments. A smaller, bi-pennate inner muscle compartment is embedded in a larger, uni-pennate outer compartment (Böl et al., 2015). As part of the calf, the plantaris is tightly packed between other muscles. It is unclear how packing affects the shape and architecture of the plantaris. Therefore, we examined the isolated and packed plantaris of the contralateral legs of three rabbits to determine the influence of the surrounding muscles on its shape and architectural properties using photogrammetric reconstruction and manual digitization, respectively. In the packed condition, the plantaris showed a 27% increase in fascicle pennation and a 54% increase in fascicle curvature compared to the isolated condition. Fascicle length was not affected by muscle packing. The change in muscle architecture occurred mainly in the outer compartment of the plantaris. Furthermore, the isolated plantaris showed a more circular shape and a reduced width of its muscle belly. It can be concluded that the packed plantaris is flattened by the forces exerted by the surrounding muscles, causing a complex architectural change. The data provided improve our understanding of muscle packages in general and can be used to develop and validate realistic three-dimensional muscle models.

The Analysis Study of Surgical Management and Outcome of Acute Compartment Syndrome: An Orthopaedic and Traumatology Systematic Review

Background: Acute compartment syndrome (ACS) is a serious medical condition that occurs when increased pressure within a closed muscle compartment reduces blood flow and can lead to permanent damage. This systematic review aims to analyze the management strategies, complications, and outcomes of acute compartment syndrome based on current literature. Methods: The review analyzed data from multiple studies, including both prospective and retrospective studies. Results: The analysis included eight studies with a total of 1,019 patients. Factors influencing outcomes in ACS included the time to fasciotomy, fracture status, muscle necrosis indicators, and patient-related factors. Early intervention and appropriate management were associated with better functional outcomes and reduced complications. Conclusion: Effective management of ACS relies heavily on timely intervention and proper post-surgical care. The studies reviewed highlight the importance of early fasciotomy and monitoring for complications to improve patient outcomes.

Heterozygous loss-of-function variants in SPTAN1 cause a novel early childhood onset distal myopathy with chronic neurogenic features.

Neurogenetic disorders caused by pathogenic variants in four genes encoding non-erythrocytic spectrins ( SPTAN1, SPTBN1, SPTBN2, SPTBN4) range from peripheral and central nervous system involvement to complex syndromic presentations. Heterozygous pathogenic variants in SPTAN1 are exemplary for this diversity with phenotypes spanning almost the entire spectrum. Through international collaboration we identified 14 families with genetically unsolved distal weakness and unreported heterozygous SPTAN1 loss-of-function variants including frameshift, nonsense and splice-acceptor variants. Clinical data, electrophysiology, muscle CT or MRI and muscle biopsy findings were collected and standardized. SPTAN1 protein, mRNA expression analysis and cDNA sequencing was performed on muscle tissue from two patients. All 20 patients presented with early childhood onset distal weakness. The severity varied both within families and between different families. Foot abnormalities ranged from hammer toes and pes cavus to distal arthrogryposis. Electrophysiology showed mixed myogenic and neurogenic features. Muscle MRI or CT in 10 patients showed fatty infiltration of the distal lower limb anterior compartment and/or selective involvement of the extensor hallucis longus muscle. Muscle biopsy revealed myopathic changes with mild dystrophic and chronic neurogenic changes in 7 patients. Finally, we provide proof for nonsense mediated decay in tissues derived from two patients. We provide evidence for the association of SPTAN1 loss-of-function variants with childhood onset distal myopathy in 14 families. This finding extends the phenotypic spectrum of SPTAN1 loss-of-function variants ranging from intellectual disability to distal weakness with a predominant myogenic cause. SPTAN1 loss-of-function variants, including frameshift, nonsense and splice site variants cause a novel childhood onset distal weakness syndrome with primarily skeletal muscle involvement. Hereditary motor neuropathies and distal myopathic disorders present a well-known diagnostic challenge as they demonstrate substantial clinical and genetic overlap. The emergence of SPTAN1 loss-of-function variants serves as a noteworthy example, highlighting a growing convergence in the spectrum of genotypes linked to both hereditary motor neuropathies and distal myopathies.

Influence of Body Composition Assessed by Computed Tomography on Mortality Risk in Young Women with Breast Cancer.

Background/Objectives: Increasing evidence indicates that body composition can significantly influence prognosis in women with breast cancer. However, alterations in body composition, particularly among young women (<40 years), remain largely unknown and underexplored. This study aimed to investigate the relationship of computed tomography (CT)-derived body composition with mortality rates among young women recently diagnosed with breast cancer, identifying the best-correlated cutoff value. Methods: This is a bi-set cohort study with retrospective data collection. Women newly diagnosed with ductal invasive breast cancer, aged 20 to 40 years, treated in reference oncology units were included. Body composition was assessed using CT scans at the third lumbar vertebra (L3) level, including muscle and adipose compartments. The outcome of interest was the incidence of overall mortality. A maximally selected log-rank Cox-derived analysis was employed to assess the cutoffs associated with mortality. Results: A total of 192 women were included before any form of treatment (median age of 35 years, IQ range: 31-37). Overall mortality occurred in 12% of the females. Stages III-IV were the most frequent (69.5%). Patients who died had a significantly lower muscle area index. CT-derived muscle area was inversely associated with mortality. Each 1 cm2/m2 decrease in skeletal muscle index increased the mortality hazard by 9%. Higher values of adiposity compartments were independently associated with higher mortality. Conclusions: Our study highlights the predictive significance of skeletal muscle area and adipose tissue in predicting survival among young women recently diagnosed with breast cancer.

Electrophysiological features of cortical 3D networks are deeply modulated by scaffold properties.

Three-dimensionality (3D) was proven essential for developing reliable models for different anatomical compartments and many diseases. However, the neuronal compartment still poses a great challenge as we still do not understand precisely how the brain computes information and how the complex chain of neuronal events can generate conscious behavior. Therefore, a comprehensive model of neuronal tissue has not yet been found. The present work was conceived in this framework: we aimed to contribute to what must be a collective effort by filling in some information on possible 3D strategies to pursue. We compared directly different kinds of scaffolds (i.e., PDMS sponges, thermally crosslinked hydrogels, and glass microbeads) in their effect on neuronal network activity recorded using micro-electrode arrays. While the overall rate of spiking activity remained consistent, the type of scaffold had a notable impact on bursting dynamics. The frequency, density of bursts, and occurrence of random spikes were all affected. The examination of inter-burst intervals revealed distinct burst generation patterns unique to different scaffold types. Network burst propagation unveiled divergent trends among configurations. Notably, it showed the most differences, underlying that functional variations may arise from a different 3D spatial organization. This evidence suggests that not all 3D neuronal constructs can sustain the same level of richness of activity. Furthermore, we commented on the reproducibility, efficacy, and scalability of the methods, where the beads still offer superior performances. By comparing different 3D scaffolds, our results move toward understanding the best strategies to develop functional 3D neuronal units for reliable pre-clinical studies.

237. THE PROGNOSTIC VALUE OF NODAL SKIP METASTASIS IN PATIENTS WITH ESOPHAGEAL CANCER

Abstract Background Nodal skip metastasis (NSM), a common form of lymphatic spread in esophageal cancer (EC), refers to metastatic involvement of distant lymph nodes (LNs) without prior engagement of adjacent LNs. Previous studies examining the association between NSM and survival outcomes in EC patients have yielded inconsistent and even contradictory results. This systematic review and meta-analysis aim to assess the prognostic value of NSM and summarize NSM definitions used in prior studies. Methods Four databases were employed for this meta-analysis. The relationship between NSM and overall survival (OS) was assessed using pooled hazard ratios (HRs) and their 95% confidence intervals (CIs). Sensitivity analysis and funnel plots were utilized to evaluate publication bias. Results This meta-analysis incorporated nine studies, and the pooled results revealed no significant association between NSM and OS (HR = 0.99, 95% CI: 0.75–1.31; P = 0.951). Sub-group analyses based on histological features, method of lymphadenectomy, node staging system, and NSM definitions also failed to identify a significant association between NSM and OS. Conclusions Based on the available evidence, NSM cannot be considered a prognostic factor for EC patients. Future studies examining the prognostic value of NSM should focus on employing three-field lymphadenectomy with an adequate number of harvested LNs. NSM definitions based on lymph node station and anatomical compartment could both serve as feasible classifications for EC.

Anconeus Exertional Compartment Syndrome and Posterolateral Rotatory Elbow Instability: A Clinical Association and Rare Cause of Elbow Pain

Background: Anconeus compartment syndrome is a rarely reported compartment syndrome in the anconeus muscle compartment of the forearm. It has anatomic and pathophysiological associations with posterolateral rotatory instability (PLRI) of the elbow. Purpose: To present the history, management, and outcomes of 4 patients with anconeus compartment syndrome. Secondary aims were to (1) establish normative anconeus pressures and (2) measure the volume of this compartment with and without PLRI in cadavers. Study Design: Case series; Level of evidence, 4. Methods: Four patients with clinical signs of anconeus compartment syndrome (2 gymnasts, 1 swimmer, and 1 footballer/weightlifter) were identified over a 3-year period (2015-2017 inclusive). Patient history, sporting activity, physical examination, anconeus compartment pressures, and treatment outcomes were recorded. Manometry of the anconeus compartment in 2 healthy male controls was performed to establish normative compartment pressures. Anconeus volumetric anatomy and the effect of creating PLRI on compartment volume was investigated in 4 cadaveric elbows. Results: All 4 patients had microtraumatic PLRI, and 2 patients had anconeus hypertrophy. Anconeus compartment pressures at rest and at 2-minutes postexercise were median 28.0 and 67.5 mm Hg, respectively, in the patients and mean 16.5 and 18 mm Hg, respectively, in the controls. Simultaneous fasciotomy and PLRI reconstructive procedures were performed in 2 patients, with outcomes showing full return to competition. Fasciotomy alone was performed in 2 patients to allow return to competition, with both requiring later reconstruction to address PLRI. Cadaver dissection revealed that the anconeus compartment was extremely small and that creation of PLRI reduced the direct volume of the compartment and increased the distance between the anconeus origin and insertion. Conclusion: Our case series demonstrated that anconeus compartment syndrome can occur in upper limb-dominant athletes in the presence of PLRI and anconeus hypertrophy. Pain is relieved by fasciotomy, but definitive treatment of the underlying instability prevents further symptomatology.

Intrahost evolution leading to distinct lineages in the upper and lower respiratory tracts during SARS-CoV-2 prolonged infection.

Accumulating evidence points to persistent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections in immunocompromised individuals as a source of novel lineages. While intrahost evolution of the virus in chronically infected patients has previously been reported, existing knowledge is primarily based on samples from the nasopharynx. In this study, we investigate the intrahost evolution and genetic diversity that accumulated during a prolonged SARS-CoV-2 infection with the Omicron BF.7 sublineage, which is estimated to have persisted for >1 year in an immunosuppressed patient. Based on the sequencing of eight samples collected at six time points, we identified 87 intrahost single-nucleotide variants, 2 indels, and a 362-bp deletion. Our analysis revealed distinct viral genotypes in the nasopharyngeal (NP), endotracheal aspirate, and bronchoalveolar lavage samples. This suggests that NP samples may not offer a comprehensive representation of the overall intrahost viral diversity. Our findings not only demonstrate that the Omicron BF.7 sublineage can further diverge from its already exceptionally mutated state but also highlight that patients chronically infected with SARS-CoV-2 can develop genetically specific viral populations across distinct anatomic compartments. This provides novel insights into the intricate nature of viral diversity and evolution dynamics in persistent infections.

Veins in the Lateral Fascial Compartment of the Calf

Venous insufficiency mostly arises from valvular incompetence in the great saphenous vein (GSV) and small saphenous vein (SSV). However, non-saphenous reflux (NSR) remains relatively unexplored in clinical practice and ultrasound investigations. This study reports an uncommon anatomical finding and the associated venous reflux, which is believed to involve the peripheral nerve. A systematic database search was conducted to identify patients from our clinic previously diagnosed with an interfascial vein in the lateral calf compartment during duplex ultrasound examination. Subsequently, a questionnaire was distributed to those who volunteered to participate, collecting further demographic details and clinical information related to peripheral neuropathy of the calf. Ultrasound findings, including venous competency and diameter measurements, were included for data analysis. In total, 20 legs with an interfascial vein were identified from 19 patients between 2008 and 2022. Of the 6 patients who returned the questionnaire and provided consent for inclusion, 2 reported lateral calf pain in the lower calf. Calf numbness was noted in 2 patients, primarily affecting the upper and mid portions with 2 further patients reporting foot drop. Reflux flow in the interfascial vein was detected in 5 patients. Sonographic findings revealed interfascial vein diameters range from 1.1 to 4.0 mm, with a mean of 2.4 mm. The distance between the interfascial vein and SSV varied, with a mean of 36.3 mm. Based on topographic anatomy and reflux flow originating from sciatic nerve varices, we hypothesize that the interfascial vein identified in our patients likely represents the superficial peroneal nerve vein. This study sheds light on the existence of an interfascial vein in the lateral calf compartment and its role in producing lateral calf neuropathy.