Neurovascular Deficits Research Articles

Comparative Analysis of Functional and Surgical Outcomes in Humeral Shaft Fractures: Interlocking Nailing vs. Dynamic Compression Plating

Background: Humeral shaft fractures account for about 3-5% of all fractures, with a 3.87% incidence in Bangladesh. These fractures often respond well to non-operative treatments like casts and braces due to the humerus's ability to tolerate malunion, leading to satisfactory outcomes. However, surgery is necessary for specific cases, including open, segmental, or pathological fractures, and when conservative treatment fails. Surgical options, like dynamic compression plates and interlocking nails, allow for quicker recovery but carry risks, including nerve damage and mechanical failure. Interlocking nails offer a less invasive option with better biomechanics but may cause shoulder complications. Aim of the study: This study aims to compare the functional and surgical outcomes of patients treated with dynamic compression plating versus those treated with interlocking nailing, to determine the most effective approach for managing humeral shaft fractures. Methods: This cross-sectional study in Department of Orthopaedic Surgery, Bangabandhu Sheikh Mujib Medical University, Bangladesh, conducted from [11/12/2022] to [20/12/2023], involved 60 patients with humerus diaphyseal fractures, divided into two groups: Group A (30 patients treated with dynamic compression plating) and Group B (30 patients treated with interlock nailing). Participants were selected based on strict inclusion/exclusion criteria, and informed consent was obtained. The study evaluated various clinical factors using standard surgical techniques. Data analysis was performed using SPSS software, with significance determined at p <0.05. Result: A prospective observational study at a tertiary care center involved 60 patients with humeral diaphyseal fractures, divided into two groups: 30 treated with dynamic compression plating (Group A) and 30 with interlocking nailing (Group B). Most participants were under 30, predominantly male, with no significant differences in age or gender distribution. Group B showed better blood management, while Group A had superior shoulder function but more shoulder stiffness. Both groups had similar operative times, elbow performance, and fracture union rates. Neurovascular deficits were more common in Group A. The study highlights different outcomes between the two treatment methods. Conclusion: This study evaluated clinical outcomes in patients, primarily under 30 years old, with a higher incidence in males and right-sided fractures. Dynamic compression plating led to longer surgeries, more significant blood loss, higher union rates, and more shoulder stiffness. Interlock nailing resulted in fewer neurovascular deficits but reduced shoulder function postoperatively.

Finding the Balance: The Point-of-Care Ultrasound Diagnosis of Pseudoaneurysm

A 49-year-old male with history of intravenous drug use presented to the Emergency Department with localized right arm swelling that has been slowly growing for months. On physical exam, there was a golf ball sized mass in the right antecubital fossa without overlying skin changes and no neurovascular deficits in the distal extremity. Point-of-care ultrasound (POCUS) was performed utilizing a water bath with visualization of bidirectional swirling in a round cavity adjacent to the brachial artery. Aneurysms are abnormal focal dilations that result from vascular wall defects. Ultrasound has been reported to have 94% sensitivity and 97% specificity for diagnosis of pseudoaneurysms. On color doppler ultrasound, pseudoaneurysm is characterized by the pathognomonic “yin-yang” sign. In the case of the 49-year-old male with a right antecubital mass and history of IVDU, the proposed mechanism of injury was trauma to the arterial wall secondary to auto-injection. POCUS has been found to improve identification of abscesses and its incorporation in patient evaluation can guide clinical management, prevent unwanted iatrogenic exsanguination, and determine whether there is a need for urgent vascular surgery intervention, particularly in high-risk patients.

Astrocyte Ca2+ dysregulation and neurovascular coupling deficits in a diet‐based mouse model of small cerebral vessel disease

AbstractBackgroundMice exposed to a diet deficient in B6/B12 vitamins and enriched in methionine exhibit hyperhomocysteinemia (HHcy) concomitant with many pathologic features of vascular cognitive impairment and dementia: a very common Alzheimer’s disease related dementia. Here, we evaluated the impact of astrocyte Ca2+ dysregulation and astrocytic Ca2+ signaling pathways in the context of functional hyperemia in fully awake mice exposed to HHcy diet.MethodAdult C57/BL6 mice were fed for 15 weeks with control chow, or chow deficient in vitamins B6/B12 and enriched in methionine (HHcy diet). Spontaneous and evoked (via air puff whisker stimulation) Ca2+ transients in astrocytes of fully awake mice were investigated in barrel cortex using the Ca2+ sensor GCaMP6f (expressed specifically in astrocytes using AAV) and two‐photon imaging. In other experiments, mice were treated with AAV‐Gfa2‐VIVIT to inhibit the Ca2+‐sensitive calcineurin/NFAT pathway in astrocytes, which regulates reactive astrocyte phenotypes. Two‐photon imaging was then used to assess diet and VIVIT effects on functional hyperemia in barrel cortex of fully awake mice.ResultCa2+ transients in individual barrel cortex astrocytes were significantly augmented (greater in amplitude, with faster rise/decay kinetics) in mice treated with HHcy diet. However, the functional connectivity in astrocyte networks of HHcy mice was significantly impaired, particularly during engagement of brain activity with whisker stimulation. Compared to control diet mice, HHcy mice also showed impaired functional hyperemia during whisker stimulation characterized by impaired arteriole dilations and reduced red blood cell velocity in nearby capillaries. Inhibition of reactive astrocyte signaling in HHcy diet mice with VIVIT significantly ameliorated these neurovascular coupling deficits.ConclusionThe results show that astrocyte Ca2+ dysregulation is a major feature of HHcy and contributes to cerebrovascular dysfunction through hyperactivation of the astrocytic CN/NFAT pathway.

Arthroscopic biceps tenodesis using press-fit bony plug: a case series study.

To assess the feasibility, operative time, clinical outcomes, possible complications, and failure rates of all-through arthroscopic biceps tenodesis using press-fit bony plug technique. This prospective case series study involved 30 skeletally mature patients with long head of biceps pathology (tendinitis after failure of conservative treatment, subluxation, dislocation, or tendon tears). All patients were followed up for 24months at least. Twenty-nine patients regained full shoulder and elbow range of motion; one case suffered from reflex sympathetic dystrophy. There was a significant improvement in the constant, ASES, and VAS scores when comparing the pre-operative and post-operative values. The average biceps strength was 96% compared to the opposite healthy side. No cases were complicated by neuro-vascular deficits or failure of the tenodesis. Press-fit biceps tenodesis is safe and accessible with low economic demands. We recommend this technique to be used more often when addressing patients with long head of biceps pathologies. Registration number: N-1562023. Registration date: June 2022 "Retrospectively registered".

Rare finding of axillary artery dissection secondary to a proximal humerus fracture-dislocation: A case report

Proximal humerus fractures are a relatively common injury, making up approximately 5% of all extremity fractures. Concurrent damage to the axillary artery, however, is not a commonly associated trauma. We present a unique case of a proximal humerus fracture-dislocation resulting in an axillary artery dissection and upper extremity ischemia, requiring emergent vascular intervention. Axillary artery injury secondary to a proximal humerus fracture-dislocation is a rare, but possibly devastating complication. A thorough physical examination to identify any neurovascular deficits is critical in determining an optimal and timely resolution.

Sex Difference in General Cognition Associated with Coupling of Whole-brain Functional Connectivity Strength to Cerebral Blood Flow Changes During Alzheimer’s Disease Progression

Alzheimer’s disease (AD) is a progressive age-related neurodegenerative disorder that results in irreversible cognitive impairments. Nonetheless, there are numerous sex-dependent differences in clinical course. We examined potential contributions of neurovascular coupling deficits to sex differences in AD progression. T1-weighted three-dimensional structural magnetic resonance images, functional blood oxygen level dependent and arterial spin labeling images were acquired from 50 AD patients (28 females), 52 amnesic mild cognitive impairment patients (31 females), and 59 healthy controls (36 females). Short- and long-range functional connectivity strength (FCS) and cerebral blood flow (CBF) values were calculated for all participants. Then, the CBF/FCS coupling ratio, which represented the amount of blood supply per unit of connectivity strength, was calculated for each voxel. Two-way ANOVA was performed to identify group × sex interactions and main effects of group. Correlation analysis was used to assess associations between CBF/FCS ratios and Mini-Mental State Examination (MMSE). There were significant group × sex interaction effects on short-range coupling ratios of right middle temporal gyrus, left angular gyrus, left inferior orbital frontal gyrus, and left superior frontal gyrus as well as on the long-range coupling ratios of right middle temporal gyrus, left precuneus, left posterior cingulate cortex, and left angular gyrus. There were significant negative correlations between MMSE scores and CBF/FCS ratios for all regions with significant group × sex interactions among female patients, while positive correlations were found among male patients. Our results demonstrate significant sex differences in neurovascular coupling mechanisms associated with cognitive function during the course of AD.

Abstract 007: Hypertension-induced Neurovascular Dysfunction At Single-cell Resolution

Hypertension (HTN) disrupts vital neurovascular control mechanisms, thereby increasing the brain’s susceptibility to vascular insufficiency, white matter lesions, and cognitive impairment. Yet, the distinct vascular, neuronal, and glial cell types targeted by HTN, as well as the ensuing cellular network disruption driving the neurovascular and cognitive deficits remain undefined. Here we sought to uncover transcriptomic changes in neurons and vascular cells using unbiased, single-cell RNA sequencing on the neocortex of 10-week old C57BL/6 male mice with angiotensin II (AngII) HTN. Vehicle or AngII (600ng/kg/min s.c.) were administered for 3 days, when blood-brain barrier (BBB) permeability start to increase, or 42 days, when neurovascular and cognitive dysfunction are fully developed (n=3/group). We analyzed 39,451 single-cell transcriptomes comprising 26 cell types. Surprisingly, 3 days of AngII induced significantly greater transcriptional changes in venular ECs compared to arteriolar ECs (EdgeR; pval< 0.05, logFC> 2), supporting the notion that venular ECs are uniquely sensitive to the early effects of HTN (Hypertension 76:795, 2020). Gene ontology analysis of differentially expressed genes prominently implicated altered venular immune signaling, BBB dysfunction, and, notably, a secretory phenotype characteristic of senescence (pval <0.05). Moreover, unbiased ligand-receptor interaction analysis (CellChat) demonstrated that senescent venular ECs strongly communicate with oligodendrocyte precursors, and NPY-expressing interneurons, pointing to a previously unrecognized early disruption in the oligo-vascular niche, essential for maintaining white matter integrity, and neuronal network stability. Furthermore, at 42 days of AngII we observed an overrepresentation of aging and neurodegeneration-linked genes in oligos and NPY interneurons, relating to myelin disruption, synaptic dysfunction, and metabolic dysregulation. The data reveal a novel endothelial-oligo-interneuron crosstalk and transcriptomic alterations underlying the impact of HTN on the brain. Future studies will establish how these transcriptomic changes are linked to neurovascular dysfunction, white matter damage and cognitive impairment.

A Modern Day Timeline for In-Hospital Monitoring in Perfused, Pulseless Pediatric Supracondylar Humerus Fractures.

The perfused, pulseless supracondylar humerus fracture (ppSCHF) remains a consistent topic of discussion in the literature. Inpatient observation of these patients postoperatively for worsening vascular exam or compartment syndrome is frequently recommended but not well studied. The purpose of this study was to evaluate the postoperative complications in a cohort of ppSCHF patients and their timeline to discharge. This study is a retrospective review of a prospectively maintained database of all operatively treated supracondylar humerus fractures from a tertiary pediatric hospital from 2013 to 2019. All patients without a palpable pulse were included. We excluded patients with <4 weeks follow-up. Demographic, operative, and postoperative data were collected, including time from presentation to operating room (OR), time from OR to discharge, and incidence of postoperative complications, including return to OR, compartment syndrome, new neurovascular deficits, and Volkmann contractures. The descriptive statistics were used to summarize the data. Among 1371 operatively treated supracondylar humerus fractures, 39 (2.8%) presented with a ppSCHF. Five (15%) had a signal on doppler ultrasound, whereas 34 (85%) had no signal. Thirty-seven (95%) patients had a Gartland type III fracture and 2 (5%) had type IV fractures. Twenty-two (56%) patients had a neurological deficit, of which 14 had an anterior interosseous nerve deficit. The average time to OR was 6.9 (range 2.2 to 15) hours; 6 (15%) required open reduction. At the time of discharge, 85% of patients had a palpable pulse and 13% had a dopplerable signal. Postoperatively, no patients were returned to the OR for any secondary procedures. The average length of stay after the operation was 25 (range 8.5 to 40) hours, with 92% of patients being discharged by 36 hours postoperatively. No patients developed compartment syndrome, new neurological deficits, or Volkmann contractures at a mean follow-up of 112 (range 34 to 310) days. In our study of 39 patients presenting with ppSCHF, no patient required an unexpected return to the OR, or developed post-treatment compartment syndrome, neurological deficits, or Volkmann contractures. The average time from OR to discharge for ppSCHF was 25 hours. Level II.

Study of suprascapular notch converted into a foramen in adult human scapulae in Karnataka region

Scapula is a triangular bone present in the back, which articulates with the humerus and clavicle forming the shoulder girdle. In the superior border of the scapula there is a notch called the suprascapular notch, through which the suprascapular nerve pass. The suprascapular nerve can be compressed by the ossified part of the transverse scapular ligament a cause for neuropathies.The present study was done on adult scapulae in department of Anatomy SUIMS &amp; R.C. Shimoga, where the transverse scapular ligament [TSL] was ossified in 10 scapulae out of 127 adult dry scapulae [7.87%] studied of unknown sex. It was also noted that 6 out of 10 scapulae belonged to the right side &amp; 4 to left side showing a slight preponderance to the right side. Incidence of the complete suprascapular foramen varies from one geographical region to other region, work nature of indivisuals and is variable with the samples collected by different workers for the study.The compresssion of the suprascapular nerve is an acquired neuropathy leading to neuromuscular deficits and decrease in the range of motion of the shoulder. Suprascapular nerve blocks are given in this region. The knowledge of this type of nerve compression is helpful for evaluation of patients with neurovascular deficits to orthopedicians, radiologists, anaesthetists and surgeons in their clinical practice.

Arthroscopic anatomic glenoid reconstruction has a lower rate of recurrent instability compared to arthroscopic Bankart repair while otherwise maintaining a similar complication and safety profile

ObjectivesThe primary purpose of this study was to determine the frequency and type of complications, including subluxation, infection, hardware complication, graft/glenoid fracture, chondrolysis, neurovascular deficits and stiffness following an Arthroscopic Bankart Repair (ABR) or an Arthroscopic Anatomic Glenoid Reconstruction (AAGR) using a distal tibia allograft for recurrent anterior shoulder instability. Secondary purposes were to determine the frank dislocation rate and the associations of post-operative complications with demographic patient factors. MethodsDemographic and clinical data were reviewed using means ± standard deviations or frequencies in patients with recurrent anterior shoulder instability who underwent either an ABR or an AAGR. Post-operative patient records were analysed to identify any post-operative complications. The numerical variables of the two groups were compared using the independent t-test or Mann–Whitney U test. Categorical variables and complications were tested using the chi-square test, Fisher’s exact test, or the two-sided Monte Carlo test with a significance level of 0.05. ResultsWe included 174 patients in this cohort, with 61.5% of patients receiving ABR and 38.5% receiving AAGR. Most of our patients were male (70.1%) with an average age of 23.41 ± 8.26 years in the ABR group and 29.37 ± 13.54 years in the AAGR group (p = 0.001). The two groups were similar with respect to their post-operative complication rates when excluding frank dislocation (ABR: 11%, AAGR: 12%). The AAGR group had statistically significantly higher rates of hardware removal compared to the ABR group (p = 0.004). The ABR group had 25 post-operative frank dislocations, with none reported in the AAGR cohort (p < 0.001). The total complication rate for each procedure was found to be 35% for ABR and 12% for AAGR. ConclusionAAGR has a comparable safety profile to the ABR when assessing post-operative complications such as subluxation, infection, graft/glenoid fracture, chondrolysis, neurovascular deficits and stiffness. AAGR is superior to ABR with respect to rates of recurrent instability and should be considered as a first-line treatment in certain patients with specific risk factors such as younger age, competitive contact sports participation, and higher number of instability events pre-operatively. Level of evidenceLevel III.

The Costs of Interfacility Transfers for Nonurgent Pediatric Supracondylar Fractures.

Unnecessary transfers of nonemergent pediatric musculoskeletal injuries to regional trauma centers can be costly. The severity of fracture displacement in supracondylar humerus fractures dictates the risk of complications, the urgency of transfer and the need for surgical treatment. The purpose of this study is to examine the transfer patterns of Gartland type II pediatric supracondylar humerus fractures to identify strategies for improving patient care, improving health care system efficiency, and reducing costs. We hypothesize that there will be a high rate of unnecessary, emergent transfers resulting in increased cost. We retrospectively identified all pediatric patients that underwent treatment for a supracondylar humerus fracture between 2013 and 2018. Patient demographics, injury characteristics, chronological data, and surgical data were collected and analyzed from ambulance run sheets, transferring hospital records, and electronic medical records. Transfer distances were estimated using Google-Maps, while transfer costs were estimated using Internal Revenue Service (IRS) standard mileage rates and the American Ambulance Association Medicare Rate Calculator. A student t test was used to evaluate different treatment groups. Sixty-two patients had available and complete transfer data, of which 44 (71%) patients were safely transferred via private vehicle an average distance of 51.8 miles, and 18 (29%) patients were transferred via ambulance on an average distance of 55.6 miles ( P =0.76). The average transfer time was 4.1 hours by private vehicle, compared with 3.9 hours by ambulance ( P =0.56). The average estimated cost of transportation was $28.23 by private vehicle, compared with $647.83 by ambulance ( P =0.0001). On average, it took 16.1 hours after injury to undergo surgery and 25.7 hours to be discharged from the hospital, without a significant difference in either of these times between groups. There were no preoperative or postoperative neurovascular deficits. Patients with isolated Gartland type II supracondylar humerus fractures that are transferred emergently via ambulance are subjected to a significantly greater financial burden with no demonstrable improvement in the quality of their care, since prior research has shown these injuries can safely be treated on an outpatient basis. Potential options to help limit costs could include greater provider education, telemedicine and improved coordination of care. Level III (retrospective comparative study).

Endosteal plating in proximal humerus fractures: a novel technique and alternative to fibular strut allograft for medial column support

The purpose of this retrospective study is to investigate the clinical and radiographic outcomes associated with the use of a standard metal plate as an endosteal implant in combination with a lateral locking plate to treat 4 patients with displaced proximal humerus fractures. A retrospective case series study design was utilized, and the medical records of 4 patients with displaced, 3-part proximal humerus fractures treated using this technique between January 2019 and July 2021 were reviewed for this study. The mean age was 52 years (range, 44-57 years). The radiographic outcome of interest was humeral neck-shaft angle preoperatively, intraoperatively, and at the latest follow-up. The average follow-up duration was 62 weeks (range, 12-161 weeks). All fractures healed without loss of reduction or neurovascular deficits. Avascular necrosis was not observed in the 2 patients with sufficient follow-up time to make such an evaluation. The average neck-shaft angles preoperatively, intraoperatively, and at the latest follow-up were 104.8°, 139.8°, and 137°, respectively. Locking plate technology augmented with an endosteal plate provided stable reduction and restoration of physiologic alignment in a small number of patients with displaced proximal humerus fractures. This construct creates a second column of fixation, providing medial column support, and could be removed in the event of a future revision to a reverse shoulder arthroplasty.

Pericyte dysfunction and loss of interpericyte tunneling nanotubes promote neurovascular deficits in glaucoma

Reduced blood flow and impaired neurovascular coupling are recognized features of glaucoma, the leading cause of irreversible blindness worldwide, but the mechanisms underlying these defects are unknown. Retinal pericytes regulate microcirculatory blood flow and coordinate neurovascular coupling through interpericyte tunneling nanotubes (IP-TNTs). Using two-photon microscope live imaging of the mouse retina, we found reduced capillary diameter and impaired blood flow at pericyte locations in eyes with high intraocular pressure, the most important risk factor to develop glaucoma. We show that IP-TNTs are structurally and functionally damaged by ocular hypertension, a response that disrupted light-evoked neurovascular coupling. Pericyte-specific inhibition of excessive Ca2+ influx rescued hemodynamic responses, protected IP-TNTs and neurovascular coupling, and enhanced retinal neuronal function as well as survival in glaucomatous retinas. Our study identifies pericytes and IP-TNTs as potential therapeutic targets to counter ocular pressure-related microvascular deficits, and provides preclinical proof of concept that strategies aimed to restore intrapericyte calcium homeostasis rescue autoregulatory blood flow and prevent neuronal dysfunction.

Traumatic Hip Dislocations in Major Trauma Patients: Epidemiology, Injury Mechanisms, and Concomitant Injuries.

Introduction: Traumatic hip dislocations (THDs) are severe injuries associated with considerable morbidity. Delayed recognition of fracture dislocations and neurovascular deficits have been proposed to cause deleterious long-term clinical outcomes. Therefore, in this study, we aimed to identify characteristics of epidemiology, injury mechanisms, and associated injuries to identify patients at risk. Methods: For this study based on the TraumaRegister DGU® (January 2002–December 2017), the inclusion criterion was an Injury Severity Score (ISS) ≥9 points. Exclusion criteria were an isolated head injury and early transfer to another hospital. The THD group was compared to a control group without hip dislocation. The ISS and New ISS were used for injury severity and the Abbreviated Injury Scale for associated injuries classification. Univariate and logistic regression analyses were performed. Results: The final study cohort comprised n = 170,934 major trauma patients. We identified 1359 individuals (0.8%) with THD; 12 patients had sustained bilateral hip dislocations. Patients with THD were predominantly male (79.5%, mean age 43 years, mean ISS 22.4 points). Aortic injuries (2.1% vs. 0.9%, p ≤ 0.001) were observed more frequently in the THD group. Among the predictors for THDs were specific injury mechanisms, including motor vehicle accidents (odds ratio (OR) 2.98, 95% confidence interval (CI) 2.57–3.45, p ≤ 0.001), motorcycle accidents (OR 1.99, 95% CI 1.66–2.39, p ≤ 0.001), and suicide attempts (OR 1.36, 95% CI 1.06–1.75, p = 0.016). Despite a lower rate of head injuries and a comparable level of care measured by trauma center admission, both intensive care unit and total hospital stay were prolonged in patients with THD. Conclusions: Since early diagnosis, as well as timely and sufficient treatment, of THDs are of high relevance for long-term outcomes of severely injured individuals, knowledge of patients at risk for this injury pattern is of utmost importance. THDs are frequently related to high-energy mechanisms and associated with severe concomitant injuries in major trauma patients.

Sevoflurane and Desflurane Exposures Following Aneurysmal Subarachnoid Hemorrhage Confer Multifaceted Protection against Delayed Cerebral Ischemia.

Numerous studies have demonstrated the ability of isoflurane conditioning to provide multifaceted protection against aneurysmal subarachnoid hemorrhage (SAH)-associated delayed cerebral ischemia (DCI); however, preclinical studies have not yet examined whether other commonly used inhalational anesthetics in neurological patients such as sevoflurane or desflurane are also protective against SAH-induced neurovascular deficits. We therefore sought to identify the potential for sevoflurane and desflurane conditioning to protect against DCI in an endovascular perforation mouse model of SAH. Neurological function was assessed daily via neuroscore. Large artery vasospasm and microvessel thrombosis were assessed three days after SAH or sham surgery. Four groups were examined: Sham, SAH + room air, SAH + 2% Sevoflurane, and SAH + 6% Desflurane. For the SAH groups, one hour after surgery, mice received 2% sevoflurane, 6% desflurane, or room air for one hour. We found that conditioning with sevoflurane or desflurane attenuated large artery vasospasm, reduced microvessel thrombosis, and improved neurologic function. Given their frequent clinical use and strong safety profile in patients (including those with SAH), these data strongly support further studies to validate these findings in preclinical and clinical studies and to elucidate the mechanisms by which these agents might be acting.

Open Supracondylar Humerus Fractures in Children.

Purpose: Supracondylar humerus (SCH) fractures are the most common elbow fracture in children; however, they rarely occur as open injuries. Open fractures are associated with higher rates of infection, neurovascular injury, compartment syndrome, and nonunion. The purpose of this study was to evaluate the treatment and outcomes of open SCH fractures in children.Methods: Between 2008 and 2015, four children (1%) had open injuries among 420 treated for SCH fractures at a single center. The mean patient age was six years (range, four to eight years). Two patients had Gustilo-Anderson grade 1 open fractures and two had grade 2 fractures. Tetanus immunization was up-to-date in all. First dose of intravenous antibiotics was given on average 3hr 7min after onset of injury (range, 1hr 38min to 8hr 15min). Time from injury to irrigation and debridement (I&D) and closed reduction and percutaneous pinning (CRPP) was on average 8hr 16min (range, 4hr 19min to 13hr 15min). All patients received 24-hour intravenous antibiotics. Pins were removed at four weeks and bony union occurred by six weeks.Results: After an average follow-up period of 12 months (range, 6 to 22 months), there were no infections, neurovascular deficits, compartment syndromes, cubitus varus deformities, or range of motion losses. All outcomes were excellent according to the Flynn criteria. Due to the unstable nature of open SCH fractures, a medial pin was used in all four cases. No loss of reduction or ulnar nerve injury occurred.Conclusion: Open injuries occur in approximately 1% of all SCH fractures in children. The authors recommend urgent intravenous antibiotics, I&D, and CRPP involving a medial pin to treat open SCH fractures. Excellent outcomes based on the Flynn criteria were obtained in four cases.

Reversed Neurovascular Coupling on Optical Coherence Tomography Angiography Is the Earliest Detectable Abnormality before Clinical Diabetic Retinopathy.

Diabetic retinopathy (DR) has traditionally been viewed as either a microvasculopathy or a neuropathy, though neurovascular coupling deficits have also been reported and could potentially be the earliest derangement in DR. To better understand neurovascular coupling in the diabetic retina, we investigated retinal hemodynamics by optical coherence tomography angiography (OCTA) in individuals with diabetes mellitus (DM) but without DR (DM no DR) and mild non-proliferative DR (mild NPDR) compared to healthy eyes. Using an experimental design to monitor the capillary responses during transition from dark adaptation to light, we examined 19 healthy, 14 DM no DR and 11 mild NPDR individuals. We found that the only structural vascular abnormality in the DM no DR group was increased superficial capillary plexus (SCP) vessel density (VD) compared to healthy eyes, while mild NPDR eyes showed significant vessel loss in the SCP at baseline. There was no significant difference in inner retinal thickness between the groups. During dark adaptation, the deep capillary plexus (DCP) VD was lower in mild NPDR individuals compared to the other two groups, which may leave the photoreceptors more susceptible to ischemia in the dark. When transitioning from dark to ambient light, both diabetic groups showed a qualitative reversal of VD trends in the SCP and middle capillary plexus (MCP), with significantly decreased SCP at 5 min and increased MCP VD at 50 s compared to healthy eyes, which may impede metabolic supply to the inner retina during light adaptation. Mild NPDR eyes also demonstrated DCP dilation at 50 s and 5 min and decreased adjusted flow index at 5 min in light. Our results show altered neurovascular responses in all three macular vascular plexuses in diabetic subjects in the absence of structural neuronal changes on high resolution imaging, suggesting that neurovascular uncoupling may be a key mechanism in the early pathogenesis of DR, well before the clinical appearance of vascular or neuronal loss.

Nrf2-regulated redox signaling in brain endothelial cells adapted to physiological oxygen levels: Consequences for sulforaphane mediated protection against hypoxia-reoxygenation

Ischemic stroke is associated with a surge in reactive oxygen species generation during reperfusion. The narrow therapeutic window for the delivery of intravenous thrombolysis and endovascular thrombectomy limits therapeutic options for patients. Thus, understanding the mechanisms regulating neurovascular redox defenses are key for improved clinical translation. Our previous studies in a rodent model of ischemic stroke established that activation of Nrf2 defense enzymes by pretreatment with sulforaphane (SFN) affords protection against neurovascular and neurological deficits. We here further investigate SFN mediated protection in mouse brain microvascular endothelial cells (bEnd.3) adapted long-term (5 days) to hyperoxic (18 kPa) and normoxic (5 kPa) O2 levels. Using an O2-sensitive phosphorescent nanoparticle probe, we measured an intracellular O2 level of 3.4 ± 0.1 kPa in bEnd 3 cells cultured under 5 kPa O2. Induction of HO-1 and GCLM by SFN (2.5 μM) was significantly attenuated in cells adapted to 5 kPa O2, despite nuclear accumulation of Nrf2. To simulate ischemic stroke, bEnd.3 cells were adapted to 18 or 5 kPa O2 and subjected to hypoxia (1 kPa O2, 1 h) and reoxygenation. In cells adapted to 18 kPa O2, reoxygenation induced free radical generation was abrogated by PEG-SOD and significantly attenuated by pretreatment with SFN (2.5 μM). Silencing Nrf2 transcription abrogated HO-1 and NQO1 induction and led to a significant increase in reoxygenation induced free radical generation. Notably, reoxygenation induced oxidative stress, assayed using the luminescence probe L-012 and fluorescence probes MitoSOX™ Red and FeRhoNox™-1, was diminished in cells cultured under 5 kPa O2, indicating an altered redox phenotype in brain microvascular cells adapted to physiological normoxia. As redox and other intracellular signaling pathways are critically affected by O2, the development of antioxidant therapies targeting the Keap1-Nrf2 defense pathway in treatment of ischemia-reperfusion injury in stroke, coronary and renal disease will require in vitro studies conducted under well-defined O2 levels.

Compartment Syndrome in Operatively Managed Pediatric Monteggia Fractures and Equivalents.

Acute compartment syndrome (ACS) is not commonly associated with pediatric Monteggia fractures or Monteggia equivalents (MF/ME). The aims of this study were: (1) To document a rate of ACS among children with operatively managed MF/ME, comparing this to the rate of ACS in classically associated Type 3 supracondylar humerus (T3-SCH) fractures at the same institution; (2) To determine which patients with MF/ME are at highest risk for ACS. Children ages 2 to 12 with MF/ME requiring operative management at an academic institution over a 14-year period were identified. The Monteggia fractures were characterized using the Bado classification; equivalent injuries were identified according to established criteria. Similarly, all patients with T3-SCH fractures managed over the same period were identified. Record review included demographic, procedural, and radiographic variables. Statistical analysis compared the rates of ACS in both groups and determined risk factors associated with developing ACS in patients with MF/ME. The rate of ACS in MF/ME was 9 of the 59 (15.3%), which was significantly higher than the rate of ACS in T3-SCH fractures 2 of the 230 (0.9%) (P=0.001). Comparing MF/ME with ACS to those without; there was no difference in sex (P=1.00), Bado Type (P=0.683), or Monteggia fracture versus equivalent (P=0.704). MF/ME with preoperative vascular deficits (22.2%) and those undergoing intramedullary fixation of the radius were more likely to develop ACS (P=0.021 and 0.015, respectively), and there was a trend toward higher rates of ACS among MF/ME with preoperative neurological deficits (P=0.064). Patients with operatively managed MF/ME had a significantly higher rate of ACS compared with patients with T3-SCH fractures. With no predisposition based on Bado classification or Monteggia fracture versus equivalent, all operatively managed MF/ME appear to be at risk for ACS. Patients with preoperative neurovascular deficits and those undergoing intramedullary radial fixation develop ACS at higher rates. Careful assessment of the forearm for signs and symptoms of ACS both before and after fixation is critical. Level III-retrospective case control.

Neuropsychological Deficits in Patients with Electrical Status Epilepticus During Sleep: A Non-invasive Analysis of Neurovascular Coupling.

To evaluate the effects of electrical status epilepticus during sleep (ESES) on cerebral blood flow (CBF) and explore the associated neuro-vascular coupling and neuropsychological deficits. 19 ESES patients were recruited to undergo real-time transcranial doppler ultrasonography (TCD) and video-EEG monitoring (vEEG). Patients were grouped based on their cognitive functions or their EEG patterns. The mean cerebral blood flow velocity (CBFVm) of the unilateral middle cerebral artery was measured using TCD and was used to calculate various relevant parameters. The 19 patients participated in a total of 54 effective TCD-vEEG monitoring sessions. We found a significant effect of clinical severity for the following measurements: spike wave index (SWI), peak and average deep sleep stage (N3) CBFVm, peak, average and minimum deep sleep and awake CBFVm, and CBFVm oscillations during deep sleep. Nevertheless, CBFVm oscillations were not related to SWI. Furthermore, CBFVm oscillations revealed a statistically significant difference between the near-ESES and asymmetric-ESES groups. CBFVm oscillations may reflect the neuro-vascular coupling process associated with ESES disfunction. Understanding the relationship between CBFVm oscillations and epileptic activity will be important for assessing the neuropsychological damage associated with ESES and for developing treatment options for this and other diseases.