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1.
Synapse ; 78(3): e22291, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38733105

RESUMO

Spinal serotonin enables neuro-motor recovery (i.e., plasticity) in patients with debilitating paralysis. While there exists time of day fluctuations in serotonin-dependent spinal plasticity, it is unknown, in humans, whether this is due to dynamic changes in spinal serotonin levels or downstream signaling processes. The primary objective of this study was to determine if time of day variations in spinal serotonin levels exists in humans. To assess this, intrathecal drains were placed in seven adults with cerebrospinal fluid (CSF) collected at diurnal (05:00 to 07:00) and nocturnal (17:00 to 19:00) intervals. High performance liquid chromatography with mass spectrometry was used to quantify CSF serotonin levels with comparisons being made using univariate analysis. From the 7 adult patients, 21 distinct CSF samples were collected: 9 during the diurnal interval and 12 during nocturnal. Diurnal CSF samples demonstrated an average serotonin level of 216.6 ± $ \pm $ 67.7 nM. Nocturnal CSF samples demonstrated an average serotonin level of 206.7 ± $ \pm $ 75.8 nM. There was no significant difference between diurnal and nocturnal CSF serotonin levels (p = .762). Within this small cohort of spine healthy adults, there were no differences in diurnal versus nocturnal spinal serotonin levels. These observations exclude spinal serotonin levels as the etiology for time of day fluctuations in serotonin-dependent spinal plasticity expression.


Assuntos
Ritmo Circadiano , Serotonina , Humanos , Serotonina/líquido cefalorraquidiano , Masculino , Adulto , Feminino , Ritmo Circadiano/fisiologia , Pessoa de Meia-Idade , Medula Espinal/metabolismo , Cromatografia Líquida de Alta Pressão , Idoso
2.
Eur Spine J ; 33(7): 2742-2750, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38522054

RESUMO

PURPOSE: Operative treatment of adult spinal deformity (ASD) has been shown to improve patient health-related quality of life (HRQOL). Selection of the uppermost instrumented vertebra (UIV) in either the upper thoracic (UT) or lower thoracic (LT) spine is a pivotal decision with effects on operative and postoperative outcomes. This review overviews the multifaceted decision-making process for UIV selection in ASD correction. METHODS: PubMed was queried for articles using the keywords "uppermost instrumented vertebra", "upper thoracic", "lower thoracic", and "adult spinal deformity". RESULTS: Optimization of UIV selection may lead to superior deformity correction, better patient-reported outcomes, and lower risk of proximal junctional kyphosis (PJK) and failure (PJF). Patient alignment characteristics, including preoperative thoracic kyphosis, coronal deformity, and the magnitude of sagittal correction influence surgical decision-making when selecting a UIV, while comorbidities such as poor body mass index, osteoporosis, and neuromuscular pathology should also be taken in to account. Additionally, surgeon experience and resources available to the hospital may also play a role in this decision. Currently, it is incompletely understood whether postoperative HRQOLs, functional and radiographic outcomes, and complications after surgery differ between selection of the UIV in either the UT or LT spine. CONCLUSION: The correct selection of the UIV in surgical planning is a challenging task, which requires attention to preoperative alignment, patient comorbidities, clinical characteristics, available resources, and surgeon-specific factors such as experience.


Assuntos
Fusão Vertebral , Vértebras Torácicas , Humanos , Vértebras Torácicas/cirurgia , Vértebras Torácicas/diagnóstico por imagem , Fusão Vertebral/métodos , Fusão Vertebral/instrumentação , Cifose/cirurgia , Curvaturas da Coluna Vertebral/cirurgia , Curvaturas da Coluna Vertebral/diagnóstico por imagem , Adulto
3.
Neurosurg Focus ; 51(5): E6, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34724639

RESUMO

OBJECTIVE: Patient feedback surveys provide important insight into patient outcomes, satisfaction, and perioperative needs. Recent critiques have questioned provider-initiated surveys and their capacity to accurately gauge patient perspectives due to intrinsic biases created by question framing. In this study, the authors sought to evaluate provider-independent, patient-controlled social media Instagram posts in order to better understand the patient experience following scoliosis correction surgery. METHODS: Twitter and Instagram were queried for posts with two tagged indicators, #scoliosissurgery or @scoliosissurgery, resulting in no relevant Twitter posts and 25,000 Instagram posts. Of the initial search, 24,500 Instagram posts that did not directly involve the patient's own experience were eliminated. Posts were analyzed and coded for the following criteria: the gender of the patient, preoperative or postoperative timing discussed in the post, and classified themes related to the patient's experiences with scoliosis correction surgery. RESULTS: Females made 87.6% of the Instagram posts about their experience following scoliosis correction surgery. The initial postoperative stage of surgery was mentioned in 7.6% of Instagram posts. The most common theme on Instagram involved offering or seeking online support from other patients, which constituted 85.2% of all posts. Other common themes included concern about the surgical scar (31.8%), discussing the results of treatment (28.8%), and relief regarding results (21.2%). CONCLUSIONS: Social media provided a platform to analyze unprompted feedback from patients. Patients were most concerned with their scoliosis correction surgery in the period of time 2 weeks or more after surgery. Themes that were most commonly found on Instagram posts were offering or seeking online support from other patients and concern about the surgical scar. Patient-controlled social media platforms, like Instagram, may provide a useful mechanism for healthcare providers to understand the patient experience following scoliosis correction surgery. Such platforms may help in evaluating postoperative satisfaction and improving postoperative quality of care.


Assuntos
Procedimentos Ortopédicos , Escoliose , Mídias Sociais , Feminino , Humanos , Procedimentos Neurocirúrgicos , Percepção , Escoliose/cirurgia
4.
J Physiol ; 597(2): 481-498, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30382587

RESUMO

KEY POINTS: Concurrent 5-HT2A (Q pathway) and 5-HT7 (S pathway) serotonin receptor activation cancels phrenic motor facilitation due to mutual cross-talk inhibition. Spinal protein kinase Cδ (PKCδ) or protein kinase A inhibition restores phrenic motor facilitation with concurrent Q and S pathway activation, demonstrating a key role for these kinases in cross-talk inhibition. Spinal PKCδ inhibition enhances adenosine-dependent severe acute intermittent hypoxia-induced phrenic long-term facilitation (S pathway), consistent with relief of cross-talk inhibition. ABSTRACT: Intermittent spinal serotonin receptor activation elicits long-lasting phrenic motor facilitation (pMF), a form of respiratory motor plasticity. When activated alone, spinal Gq protein-coupled serotonin 2A receptors (5-HT2A ) initiate pMF by a mechanism that requires ERK-MAP kinase signalling and new BDNF protein synthesis (Q pathway). Spinal Gs protein-coupled serotonin 7 (5-HT7 ) and adenosine 2A (A2A ) receptor activation also elicits pMF, but via distinct mechanisms (S pathway) that require Akt signalling and new TrkB protein synthesis. Although studies have shown inhibitory cross-talk interactions between these competing pathways, the underlying cellular mechanisms are unknown. We propose the following hypotheses: (1) concurrent 5-HT2A and 5-HT7 activation undermines pMF; (2) protein kinase A (PKA) and (3) NADPH oxidase mediate inhibitory interactions between Q (5-HT2A ) and S (5-HT7 ) pathways. Selective 5-HT2A (DOI hydrochloride) and 5HT7 (AS-19) agonists were administered intrathecally at C4 (three injections, 5-min intervals) in anaesthetized, vagotomized and ventilated male rats. With either spinal 5-HT2A or 5-HT7 activation alone, phrenic amplitude progressively increased (pMF). In contrast, concurrent 5-HT2A and 5-HT7 activation failed to elicit pMF. The 5-HT2A -induced Q pathway was restored by inhibiting PKA activity (Rp-8-Br-cAMPS). NADPH oxidase inhibition did not prevent cross-talk inhibition. Therefore, we investigated alternative mechanisms to explain Q to S pathway inhibition. Spinal protein kinase C (PKC) inhibition with Gö6983 or PKCδ peptide inhibitor restored the 5-HT7 -induced S pathway to pMF, revealing PKCδ as the relevant isoform. Spinal PKCδ inhibition enhanced the S pathway-dependent form of pMF elicited by severe acute intermittent hypoxia. We suggest that powerful constraints between 5-HT2A and 5-HT7 or A2A receptor-induced pMF are mediated by PKCδ and PKA, respectively.


Assuntos
Hipóxia/fisiopatologia , Nervo Frênico/fisiologia , Proteína Quinase C-delta/fisiologia , Receptor 5-HT2A de Serotonina/fisiologia , Receptores de Serotonina/fisiologia , Medula Espinal/fisiologia , Anfetaminas/farmacologia , Animais , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Proteínas Quinases Dependentes de AMP Cíclico/fisiologia , Masculino , Proteína Quinase C-delta/antagonistas & inibidores , Pirazóis/farmacologia , Ratos Sprague-Dawley , Agonistas do Receptor de Serotonina/farmacologia , Tetra-Hidronaftalenos/farmacologia
5.
J Physiol ; 597(15): 3951-3967, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31280489

RESUMO

KEY POINTS: Intermittent reductions in respiratory neural activity, a characteristic of many ventilatory disorders, leads to inadequate ventilation and arterial hypoxia. Both intermittent reductions in respiratory neural activity and intermittent hypoxia trigger compensatory enhancements in inspiratory output when experienced separately, forms of plasticity called inactivity-induced inspiratory motor facilitation (iMF) and long-term facilitation (LTF), respectively. Reductions in respiratory neural activity that lead to moderate, but not mild, arterial hypoxia occludes plasticity expression, indicating that concurrent induction of iMF and LTF impairs plasticity through cross-talk inhibition of their respective signalling pathways. Moderate hypoxia undermines iMF by enhancing NR2B-containing NMDA receptor signalling, which can be rescued by exogenous retinoic acid, a molecule necessary for iMF. These data suggest that in ventilatory disorders characterized by reduced inspiratory motor output, such as sleep apnoea, endogenous mechanisms of compensatory plasticity may be impaired, and that exogenously activating respiratory plasticity may be a novel strategy to improve breathing. ABSTRACT: Many forms of sleep apnoea are characterized by recurrent reductions in respiratory neural activity, which leads to inadequate ventilation and arterial hypoxia. Both recurrent reductions in respiratory neural activity and hypoxia activate mechanisms of compensatory plasticity that augment inspiratory output and lower the threshold for apnoea, inactivity-induced inspiratory motor facilitation (iMF) and long-term facilitation (LTF), respectively. However, despite frequent concurrence of reduced respiratory neural activity and hypoxia, mechanisms that induce and regulate iMF and LTF have only been studied separately. Here, we demonstrate that recurrent reductions in respiratory neural activity ('neural apnoea') accompanied by cessations in ventilation that result in moderate (but not mild) hypoxaemia do not elicit increased inspiratory output, suggesting that concurrent induction of iMF and LTF occludes plasticity. A key role for NMDA receptor activation in impairing plasticity following concurrent neural apnoea and hypoxia is indicated since recurrent hypoxic neural apnoeas triggered increased phrenic inspiratory output in rats in which spinal NR2B-containing NMDA receptors were inhibited. Spinal application of retinoic acid, a key molecule necessary for iMF, bypasses NMDA receptor-mediated constraints, thereby rescuing plasticity following hypoxic neural apnoeas. These studies raise the intriguing possibility that endogenous mechanisms of compensatory plasticity may be impaired in some individuals with sleep apnoea, and that exogenously activating pathways giving rise to respiratory plasticity may be a novel pharmacological strategy to improve breathing.


Assuntos
Hipóxia/fisiopatologia , Plasticidade Neuronal , Síndromes da Apneia do Sono/fisiopatologia , Animais , Homeostase , Hipóxia/metabolismo , Masculino , Oxigênio/metabolismo , Nervo Frênico/metabolismo , Nervo Frênico/fisiopatologia , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/metabolismo , Síndromes da Apneia do Sono/metabolismo
6.
Am J Physiol Regul Integr Comp Physiol ; 314(5): R709-R715, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29384698

RESUMO

Intermittent spinal serotonin receptor activation elicits phrenic motor facilitation (pMF), a form of spinal respiratory motor plasticity. Episodic activation of either serotonin type 2 (5-HT2) or type 7 (5-HT7) receptors elicits pMF, although they do so via distinct cellular mechanisms known as the Q (5-HT2) and S (5-HT7) pathways to pMF. When coactivated, these pathways interact via mutual cross-talk inhibition. Although we have a rudimentary understanding of mechanisms mediating cross-talk interactions between spinal 5-HT2 subtype A (5-HT2A) and 5-HT7 receptor activation, we do not know if similar interactions exist between 5-HT2 subtype B (5-HT2B) and 5-HT7 receptors. We confirmed that either spinal 5-HT2B or 5-HT7 receptor activation alone elicits pMF and tested the hypotheses that 1) concurrent activation of both receptors suppresses pMF due to cross-talk inhibition; 2) 5-HT7 receptor inhibition of 5-HT2B receptor-induced pMF requires protein kinase A (PKA) activity; and 3) 5-HT2B receptor inhibition of 5-HT7 receptor-induced pMF requires NADPH oxidase (NOX) activity. Selective 5-HT2B and 5-HT7 receptor agonists were administered intrathecally at C4 (3 injections, 5-min intervals) to anesthetized, paralyzed, and ventilated rats. Whereas integrated phrenic nerve burst amplitude increased after selective spinal 5-HT2B or 5-HT7 receptor activation alone (i.e., pMF), pMF was no longer observed with concurrent 5-HT2B and 5-HT7 receptor agonist administration. With concurrent receptor activation, pMF was rescued by inhibiting either NOX or PKA activity, demonstrating their roles in cross-talk inhibition between these pathways to pMF. This report demonstrates cross-talk inhibition between 5-HT2B- and 5-HT7 receptor-induced pMF and that NOX and PKA activity are necessary for that cross-talk inhibition.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Diafragma/inervação , Potenciação de Longa Duração , NADPH Oxidases/metabolismo , Nervo Frênico/metabolismo , Receptor Cross-Talk , Receptor 5-HT2B de Serotonina/metabolismo , Receptores de Serotonina/metabolismo , Nervos Espinhais/enzimologia , Potenciais de Ação , Animais , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Potenciação de Longa Duração/efeitos dos fármacos , Masculino , NADPH Oxidases/antagonistas & inibidores , Nervo Frênico/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Ratos Sprague-Dawley , Receptor Cross-Talk/efeitos dos fármacos , Receptor 5-HT2B de Serotonina/efeitos dos fármacos , Receptores de Serotonina/efeitos dos fármacos , Respiração , Antagonistas da Serotonina/farmacologia , Agonistas do Receptor de Serotonina/farmacologia , Transdução de Sinais , Nervos Espinhais/efeitos dos fármacos , Fatores de Tempo
7.
J Neurosci ; 35(21): 8107-17, 2015 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-26019328

RESUMO

Acute intermittent hypoxia (AIH) induces a form of spinal motor plasticity known as phrenic long-term facilitation (pLTF); pLTF is a prolonged increase in phrenic motor output after AIH has ended. In anesthetized rats, we demonstrate that pLTF requires activity of the novel PKC isoform, PKCθ, and that the relevant PKCθ is within phrenic motor neurons. Whereas spinal PKCθ inhibitors block pLTF, inhibitors targeting other PKC isoforms do not. PKCθ is highly expressed in phrenic motor neurons, and PKCθ knockdown with intrapleural siRNAs abolishes pLTF. Intrapleural siRNAs targeting PKCζ, an atypical PKC isoform expressed in phrenic motor neurons that underlies a distinct form of phrenic motor plasticity, does not affect pLTF. Thus, PKCθ plays a critical role in spinal AIH-induced respiratory motor plasticity, and the relevant PKCθ is localized within phrenic motor neurons. Intrapleural siRNA delivery has considerable potential as a therapeutic tool to selectively manipulate plasticity in vital respiratory motor neurons.


Assuntos
Hipóxia/enzimologia , Isoenzimas/metabolismo , Potenciação de Longa Duração/fisiologia , Neurônios Motores/enzimologia , Nervo Frênico/enzimologia , Proteína Quinase C/metabolismo , Animais , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/fisiologia , Hipóxia/fisiopatologia , Isoenzimas/antagonistas & inibidores , Potenciação de Longa Duração/efeitos dos fármacos , Masculino , Neurônios Motores/efeitos dos fármacos , Nervo Frênico/efeitos dos fármacos , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C-theta , Inibidores de Proteínas Quinases/farmacologia , Ratos , Ratos Sprague-Dawley
8.
J Neurophysiol ; 114(3): 1784-91, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26224775

RESUMO

Phrenic long-term facilitation (pLTF) is a persistent increase in phrenic nerve activity after acute intermittent hypoxia (AIH). Distinct cell-signaling cascades give rise to pLTF depending on the severity of hypoxemia within hypoxic episodes. Moderate AIH (mAIH; three 5-min episodes, PaO2 ∼35-55 mmHG) elicits pLTF by a serotonin (5-HT)-dependent mechanism that requires new synthesis of brain-derived neurotrophic factor (BDNF), activation of its high-affinity receptor (TrkB), and ERK MAPK signaling. In contrast, severe AIH (sAIH; three 5-min episodes, PaO2 ∼25-30 mmHG) elicits pLTF by an adenosine-dependent mechanism that requires new TrkB synthesis and Akt signaling. Although both mechanisms require spinal protein synthesis, the newly synthesized proteins are distinct, as are the neurochemicals inducing plasticity (serotonin vs. adenosine). In many forms of neuroplasticity, new protein synthesis requires translational regulation via mammalian target of rapamycin (mTOR) signaling. Since Akt regulates mTOR activity, we hypothesized that mTOR activity is necessary for sAIH- but not mAIH-induced pLTF. Phrenic nerve activity in anesthetized, paralyzed, and ventilated rats was recorded before, during, and 60 min after mAIH or sAIH. Rats were pretreated with intrathecal injections of 20% DMSO (vehicle controls) or rapamycin (0.1 mM, 12 µl), a selective mTOR complex 1 inhibitor. Consistent with our hypothesis, rapamycin blocked sAIH- but not mAIH-induced pLTF. Thus spinal mTOR activity is required for adenosine-dependent (sAIH) but not serotonin-dependent (mAIH) pLTF, suggesting that distinct mechanisms regulate new protein synthesis in these forms of spinal neuroplasticity.


Assuntos
Hipóxia/metabolismo , Potenciação de Longa Duração , Complexos Multiproteicos/metabolismo , Nervo Frênico/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Adenosina/metabolismo , Animais , Hipóxia/fisiopatologia , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina , Nervo Frênico/fisiologia , Ratos , Ratos Sprague-Dawley
9.
Asian J Neurosurg ; 19(2): 317-320, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38974458

RESUMO

Objectives Expandable transforaminal interbody fusion (TLIF) devices have been developed to introduce more segmental lordosis through a narrow operative corridor, but there are concerns about the degree of achievable correction with a small graft footprint. In this report, we describe the technical nuances associated with placing bilateral expandable cages for correction of iatrogenic deformity. Materials and Methods A 60-year-old female with symptomatic global sagittal malalignment and a severe lumbar kyphotic deformity after five prior lumbar surgeries presented to our institution. We performed multilevel posterior column osteotomies, a L3-4 intradiscal osteotomy, and placed bilateral lordotic expandable TLIF cages at the level of maximum segmental kyphosis. Results We achieve a 21-degree correction of the patient's focal kyphotic deformity and restoration of the patient global sagittal alignment. Conclusion This case demonstrates both the feasibility and utility of placing bilateral expandable TLIF cages at a single disc space in the setting of severe focal sagittal malalignment. This technique expands the implant footprint and, when coupled with an intradiscal osteotomy, allows for a significant restoration of segmental lordosis.

10.
J Clin Neurosci ; 127: 110757, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39059336

RESUMO

BACKGROUND: Spinal cord hypoperfusion undermines clinical recovery in acute traumatic spinal cord injuries. New guidelines suggest cerebrospinal fluid (CSF) drainage is an important strategy for preventing spinal cord hypoperfusion in the acute post-injury phase. METHODS: This study included participants presenting to a single level 1 trauma center between 2018 and 2022 with cervical or thoracic traumatic spinal cord injury severity grade A-C, as evaluated by the American spinal injury association impairment scale (AIS). The primary objective of this study was to compare the efficacy of two CSF drainage protocols in preventing spinal cord hypoperfusion; 1) draining CSF only when spinal cord perfusion pressure (SCPP) drops below 65 mmHg (i.e. reactive) versus 2) empiric CSF drainage of 5-10 mL every hour. Intrathecal pressure, spinal cord perfusion pressure (SCPP), mean arterial pressure (MAP), and vasopressor utilization were compared using univariate T-test statistical analysis. RESULTS: While there was no difference in the incidence of sub-optimal SCPP (<65 mmHg; p = 0.1658), reactively drained participants were more likely to exhibit critical hypoperfusion (<50 mmHg; p = 0.0030) despite also having lower average intrathecal pressures (p < 0.001). There were no differences in average SCPP, mean arterial pressure (MAP), or vasopressor utilization between the two groups (p > 0.05). CONCLUSIONS: Empiric (vs reactive) CSF drainage resulted in fewer incidences of critical spinal cord hypoperfusion for patients with acute traumatic spinal cord injuries.


Assuntos
Drenagem , Traumatismos da Medula Espinal , Humanos , Traumatismos da Medula Espinal/terapia , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Drenagem/métodos , Estudos Retrospectivos , Pressão do Líquido Cefalorraquidiano/fisiologia , Idoso , Adulto Jovem
11.
World Neurosurg ; 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39153569

RESUMO

BACKGROUND: Proper documentation is essential for patient care. The popularity of artificial intelligence (AI) offers the potential for improvements in neurosurgical note-writing. The study aimed to assess how AI can optimize documentation in neurosurgical procedures. METHODS: Thirty-six notes were included. All identifiable data were removed. Essential information, such as perioperative data and diagnosis, was sourced from these notes. ChatGPT 4.0 was trained to draft notes from surgical vignettes using each surgeon's note template. One hundred forty-four surveys, with a surgeon or AI note, were shared with three surgeons to evaluate accuracy, content, and organization using a five-point scale. Accuracy was the factual correctness. Content was the comprehensiveness. Organization was the arrangement of the note. Flesch-Kincaid Grade Level (FKGL) and Flesch Reading Ease (FRE) scores quantified each note's readability. RESULTS: The mean AI accuracy (4.44) was not different from the mean surgeon accuracy (4.33, p = 0.512). The mean AI content (3.73) was lower than the mean surgeon content (4.42, p < 0.001). The mean AI organization (4.54) was greater than the mean surgeon organization (4.24, p = 0.064). The mean AI note's FKGL (13.13) was greater than the mean surgeon FKGL (9.99, p <0.001). The mean AI FRE (21.42) was lower than the mean surgeon FRE (41.70, p <0.001). CONCLUSION: AI notes were on par with surgeon notes in accuracy and organization, but lacked in content. Additionally, AI notes utilized language at an advanced reading level. These findings underscore the potential for ChatGPT to enhance the efficiency of neurosurgery documentation.

12.
Neurosurgery ; 95(3): 676-681, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38551355

RESUMO

BACKGROUND AND OBJECTIVES: Nearly 30% of older adults presenting with isolated spine fractures will die within 1 year. Attempts to ameliorate this alarming statistic are hindered by our inability to identify relevant risk factors. The primary objective of this study was to develop a prediction model that identifies feasible targets to limit 1-year mortality. METHODS: This retrospective cohort study included 703 older adults (65 years or older) admitted to a level I trauma center with isolated spine fractures, without neural deficit, from January 2013 to January 2018. Multivariable analysis was used to select for independently significant patient demographics, frailty variables, injury metrics, and management decisions to incorporate into distinct logistic regression models predicting 1-year mortality. Variables were considered significant, if P < .05. RESULTS: Of the 703 older adults, 199 (28.3%) died after hospital discharge, but within 1 year of index trauma. Risk Analysis Index (RAI; odds ratio [OR]: 1.116; 95% CI: 1.087-1.149; P < .001) and ambulation requiring a cane (OR: 2.601; 95% CI: 1.151-5.799; P = .02) or walker (OR: 4.942; 95% CI: 2.698-9.196; P < .001), ie, frailty variables, were associated with increased odds of 1-year mortality. Spine trauma scales were not associated with 1-year mortality. Longer hospital stays (OR: 1.112; 95% CI: 1.034-1.196; P = .004) and nursing home discharge (OR: 3.881; 95% CI: 2.070-7.378; P < .001) were associated with increased odds, while discharge to rehab (OR: 0.361; 95% CI: 0.155-0.799; P = .014) decreased 1-year mortality odds. A "preinjury" regression model incorporating Risk Analysis Index and ambulation status resulted in an area under receiver operating characteristic curve (AUROCC) of 0.914 (95% CI: 0.863-0.965). A "postinjury" model incorporating Glasgow Coma Scale, hospital stay duration, and discharge disposition resulted in AUROCC of 0.746 (95% CI: 0.642-0.849). Combining elements of the preinjury and postinjury models into an "integrated model" produced an AUROCC of 0.908 (95% CI: 0.852-0.965). CONCLUSION: Preinjury frailty measures are most strongly associated with 1-year mortality outcomes in older adults with isolated spine fractures. Incorporating injury metrics or management decisions did not enhance predictive accuracy. Further work is needed to understand how targeting frailty may reduce mortality.


Assuntos
Fragilidade , Fraturas da Coluna Vertebral , Humanos , Feminino , Idoso , Masculino , Fragilidade/mortalidade , Fraturas da Coluna Vertebral/mortalidade , Estudos Retrospectivos , Idoso de 80 Anos ou mais , Estudos de Coortes , Fatores de Risco
13.
World Neurosurg ; 184: e137-e143, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38253177

RESUMO

BACKGROUND: Preoperative symptom severity in cervical spondylotic myelopathy (CSM) can be variable. Radiomic signatures could provide an imaging biomarker for symptom severity in CSM. This study utilizes radiomic signatures of T1-weighted and T2-weighted magnetic resonance imaging images to correlate with preoperative symptom severity based on modified Japanese Orthopaedic Association (mJOA) scores for patients with CSM. METHODS: Sixty-two patients with CSM were identified. Preoperative T1-weighted and T2-weighted magnetic resonance imaging images for each patient were segmented from C2-C7. A total of 205 texture features were extracted from each volume of interest. After feature normalization, each second-order feature was further subdivided to yield a total of 400 features from each volume of interest for analysis. Supervised machine learning was used to build radiomic models. RESULTS: The patient cohort had a median mJOA preoperative score of 13; of which, 30 patients had a score of >13 (low severity) and 32 patients had a score of ≤13 (high severity). Radiomic analysis of T2-weighted imaging resulted in 4 radiomic signatures that correlated with preoperative mJOA with a sensitivity, specificity, and accuracy of 78%, 89%, and 83%, respectively (P < 0.004). The area under the curve value for the ROC curves were 0.69, 0.70, and 0.77 for models generated by independent T1 texture features, T1 and T2 texture features in combination, and independent T2 texture features, respectively. CONCLUSIONS: Radiomic models correlate with preoperative mJOA scores using T2 texture features in patients with CSM. This may serve as a surrogate, objective imaging biomarker to measure the preoperative functional status of patients.


Assuntos
Doenças da Medula Espinal , Espondilose , Humanos , Resultado do Tratamento , Radiômica , Doenças da Medula Espinal/diagnóstico por imagem , Doenças da Medula Espinal/cirurgia , Doenças da Medula Espinal/patologia , Imageamento por Ressonância Magnética/métodos , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Vértebras Cervicais/patologia , Espondilose/diagnóstico por imagem , Espondilose/cirurgia , Espondilose/complicações , Biomarcadores
14.
Res Sq ; 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38260333

RESUMO

Spinal cord stimulation (SCS) restores motor control after spinal cord injury (SCI) and stroke. This evidence led to the hypothesis that SCS facilitates residual supraspinal inputs to spinal motoneurons. Instead, here we show that SCS does not facilitate residual supraspinal inputs but directly triggers motoneurons action potentials. However, supraspinal inputs can shape SCS-mediated activity, mimicking volitional control of motoneuron firing. Specifically, by combining simulations, intraspinal electrophysiology in monkeys and single motor unit recordings in humans with motor paralysis, we found that residual supraspinal inputs transform subthreshold SCS-induced excitatory postsynaptic potentials into suprathreshold events. We then demonstrated that only a restricted set of stimulation parameters enables volitional control of motoneuron firing and that lesion severity further restricts the set of effective parameters. Our results explain the facilitation of voluntary motor control during SCS while predicting the limitations of this neurotechnology in cases of severe loss of supraspinal axons.

15.
J Neurosurg Spine ; 40(5): 653-661, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38335527

RESUMO

OBJECTIVE: The objective was to evaluate the efficacy, outcomes, and complications of surgical intervention performed within 24 hours (≤ 24 hours) versus after 24 hours (> 24 hours) in managing acute traumatic central cord syndrome (ATCCS). METHODS: Articles pertinent to the study were retrieved from PubMed, Scopus, Web of Science, and Cochrane. The authors performed a systematic review and meta-analysis of treatment procedures and outcomes according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRIMSA) guidelines. RESULTS: Seven articles comprising 488 patients were included, with 188 (38.5%) patients in the ≤ 24-hour group and 300 (61.5%) in the > 24-hour group. Significant differences were not found between groups in terms of demographic characteristics, injury mechanism, spinal cord compression level, neuroimaging features, and the American Spinal Injury Association (ASIA) motor score at admission. Both groups had a similar approach to surgery and steroid administration. The surgical complication rate was significantly higher in the > 24-hour group (4.5%) compared to the ≤ 24-hour group (1.2%) (p = 0.05). Clinical follow-up duration was similar at 12 months (interquartile range 3-36) for both groups (p > 0.99). The ≤ 24-hour group demonstrated a not statistically significant greater improvement in ASIA motor score, with a mean difference of 12 (95% CI -20.7 to 44.6) compared to the > 24-hour group. CONCLUSIONS: The present study indicates potential advantages of early (≤ 24 hours) surgery in ATCCS patients, specifically in terms of lower complication rates. However, further research is needed to confirm these findings and their clinical implications.


Assuntos
Síndrome Medular Central , Humanos , Síndrome Medular Central/cirurgia , Tempo para o Tratamento , Fatores de Tempo , Resultado do Tratamento , Procedimentos Neurocirúrgicos/métodos , Traumatismos da Medula Espinal/cirurgia , Descompressão Cirúrgica/métodos , Complicações Pós-Operatórias
16.
medRxiv ; 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38712177

RESUMO

Intracortical microstimulation (ICMS) is a method for restoring sensation to people with paralysis as part of a bidirectional brain-computer interface to restore upper limb function. Evoking tactile sensations of the hand through ICMS requires precise targeting of implanted electrodes. Here we describe the presurgical imaging procedures used to generate functional maps of the hand area of the somatosensory cortex and subsequent planning that guided the implantation of intracortical microelectrode arrays. In five participants with cervical spinal cord injury, across two study locations, this procedure successfully enabled ICMS-evoked sensations localized to at least the first four digits of the hand. The imaging and planning procedures developed through this clinical trial provide a roadmap for other brain-computer interface studies to ensure successful placement of stimulation electrodes.

17.
World Neurosurg X ; 20: 100235, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37456687

RESUMO

Within the sample of 181 patients with cervical CT, CT identified unstable injury with a sensitivity of 100% and specificity of 95%. CT identified operable injury at the CCJ with 86% sensitivity and 91% specificity. CT was considered the gold standard for identification of fractures. Together, the presence of CT imaging suggestive of unstable injury or persistent neurologic complaint had a 100% sensitivity and 81% specificity. Finally, across all patients MRI had 100% sensitivity and 89% specificity for detection of unstable injury requiring surgery.

18.
J Craniovertebr Junction Spine ; 14(2): 127-136, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37448498

RESUMO

Introduction: Lateral anterior column release (ACR) is a minimally invasive option for the correction of sagittal plane deformity. To assemble a homogeneous picture of published research on ACR, an advanced bibliometric analysis was conducted to compile the top-ten most-cited articles on the topic of ACR. Methods: A keyword search using the Thomson Reuters Web of Knowledge was conducted to identify articles discussing the role of lateral ACR. The articles were then ranked based on the total number of citations to identify the ten most-cited articles published. A subjective appraisal of the findings of these articles was conducted to provide a ranked literature review and to examine trends in the study of ACR between 2012 and 2019. Results: The earliest published article on ACR was in 2012 by Deukmedjian et al. Three articles were in vitro biomechanical assessments of ACR, and seven articles were on outcome analyses, which were either case series or case controlled. The most-cited article was a biomechanical study authored by Uribe et al. The article with the highest rate of citations/year was authored by Manwaring et al. Uribe and the European Spine Journal were the most frequently cited author and journal, respectively. Conclusions: The lateral ACR approach has enjoyed significant scholarly attention since its advent. Higher-level analyses with robust control groups, larger sample sizes, and long-term follow-up are necessary to improve our understanding of this approach.

19.
Asian J Neurosurg ; 18(3): 676-678, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38152540

RESUMO

Rudimentary meningoceles of the spine with dural extension are very rare and warrant surgical excision to prevent infection and long-term neurological deficits in pediatric patients. We present the case of a 5-month-old infant with a tethered spinal cord secondary to a rudimentary meningocele. The patient presented shortly after birth with a midline cervical dimple that was evaluated for a suspected dermal sinus tract. Magnetic resonance imaging scan of the spine showed a sinus tract with intradural extension to C2-3 and external opening at the level of spinous process C5. En bloc surgical excision and spinal cord release were successfully performed. Histological analysis of the specimen confirmed the presence of two blunt sinus tracts and staining was consistent with a rudimentary meningocele. Intradural rudimentary meningoceles in infants can successfully be managed with surgical intervention. Surgery is indicated to prevent future motor complications from spinal cord tethering and neoplastic growth from the rudimentary meningocele.

20.
World Neurosurg ; 180: e786-e790, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37852474

RESUMO

BACKGROUND: A clinical concern exists that pediatric patients with whiplash-associated disorder (WAD) might have missed structural injuries or, alternatively, subsequently develop structural injuries over time, despite initially negative imaging findings. The primary objective of this study is to assess follow-up imaging usage for pediatric patients presenting with WAD. METHODS: A retrospective review of 444 pediatric patients presenting to a level 1 pediatric trauma hospital from January 1, 2010 to December 31, 2019 was performed. Imaging was reviewed at the initial encounter and the 3- and 6-month follow-up appointments. RESULTS: At the initial evaluation, children aged <6 years were more likely to receive radiographs (P = 0.007) and magnetic resonance imaging (P = 0.048) than were children aged 6-11 and 12-18 years. At the 3- and 6-month follow-up appointments, persistent neck pain was rare, representing <15% of patients at either time. Regardless of pain persistence, 80.2% of patients seen at the 3-month follow-up and 100% of patients at the 6-month follow-up underwent additional imaging studies. At the 3-month follow-up, children with persistent neck pain were more likely to undergo magnetic resonance imaging than were patients without persistent pain (P < 0.001). Also, patients with persistent neck pain were also more likely to not undergo any imaging evaluation (P = 0.002). Follow-up imaging studies did not reveal new structural injuries at either time point. CONCLUSIONS: Follow-up imaging for pediatric patients with low-grade WAD did not identify new structural pathology-in patients with or without persistent neck pain.


Assuntos
Cervicalgia , Traumatismos em Chicotada , Humanos , Criança , Cervicalgia/complicações , Seguimentos , Traumatismos em Chicotada/complicações , Traumatismos em Chicotada/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Radiografia
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