Evaluating tissue injury in cervical spondylotic myelopathy with spinal cord MRI: a systematic review.

PURPOSE: Cervical Spondylotic Myelopathy (CSM) is a degenerative condition that leads to loss of cervical spinal cord (CSC) integrity. Various spinal cord Magnetic Resonance Imaging (MRI) methods can identify and characterize the extent of this damage. This systematic review aimed to evaluate the diagnostic, biomarker, and predictive utilities of different spinal cord MRI methods in clinical research studies of CSM. The aim was to provide a comprehensive understanding of the progress in this direction for future studies and effective diagnosis and management of CSM. METHODS: A comprehensive literature search was conducted on PubMed and EMBASE from 2010 to 2022 according to PRISMA guidelines. Studies with non-human subjects, less than 3T magnetic field strength, non-clinical design, or not quantitatively focusing on the structural integrity of CSC were excluded. The extracted data from each study included demographics, disease severity, MRI machine characteristics, quantitative metrics, and key findings in terms of diagnostic, biomarker, and predictive utilities of each MRI method. The risk of bias was performed using the guide from AHRQ. The quality of evidence was assessed separately for each type of utility for different MRI methods using GRADE. RESULTS: Forty-seven studies met the inclusion criteria, utilizing diffusion-weighted imaging (DTI) (n = 39), magnetization transfer (MT) (n = 6), MR spectroscopy (n = 3), and myelin water imaging (n = 1), as well as a combination of MRI methods (n = 12). The metric fractional anisotropy (FA) showed the highest potential in all facets of utilities, followed by mean diffusivity. Other promising metrics included MT ratio and intracellular volume fraction, especially in multimodal studies. However, the level of evidence for these promising metrics was low due to a small number of studies. Some studies, mainly DTI, also reported the usefulness of spinal cord MRI in mild CSM. CONCLUSIONS: Spinal cord MRI methods can potentially facilitate the diagnosis and management of CSM by quantitatively interrogating the structural integrity of CSC. DTI is the most promising MRI method, and other techniques have also shown promise, especially in multimodal configurations. However, this field is in its early stages, and more studies are needed to establish the usefulness of spinal cord MRI in CSM.

Neurovascular coupling, functional connectivity, and cerebrovascular endothelial extracellular vesicles as biomarkers of mild cognitive impairment.

INTRODUCTION: Mild cognitive impairment (MCI) is a prodromal stage of dementia. Understanding the mechanistic changes from healthy aging to MCI is critical for comprehending disease progression and enabling preventative intervention. METHODS: Patients with MCI and age-matched controls (CN) were administered cognitive tasks during functional near-infrared spectroscopy (fNIRS) recording, and changes in plasma levels of extracellular vesicles (EVs) were assessed using small-particle flow cytometry. RESULTS: Neurovascular coupling (NVC) and functional connectivity (FC) were decreased in MCI compared to CN, prominently in the left-dorsolateral prefrontal cortex (LDLPFC). We observed an increased ratio of cerebrovascular endothelial EVs (CEEVs) to total endothelial EVs in patients with MCI compared to CN, correlating with structural MRI small vessel ischemic damage in MCI. LDLPFC NVC, CEEV ratio, and LDLPFC FC had the highest feature importance in the random Forest group classification. DISCUSSION: NVC, CEEVs, and FC predict MCI diagnosis, indicating their potential as markers for MCI cerebrovascular pathology. HIGHLIGHTS: Neurovascular coupling (NVC) is impaired in mild cognitive impairment (MCI). Functional connectivity (FC) compensation mechanism is lost in MCI. Cerebrovascular endothelial extracellular vesicles (CEEVs) are increased in MCI. CEEV load strongly associates with cerebral small vessel ischemic lesions in MCI. NVC, CEEVs, and FC predict MCI diagnosis over demographic and comorbidity factors.

Utility of machine learning algorithms in degenerative cervical and lumbar spine disease: a systematic review.

Machine learning is a rapidly evolving field that offers physicians an innovative and comprehensive mechanism to examine various aspects of patient data. Cervical and lumbar degenerative spine disorders are commonly age-related disease processes that can utilize machine learning to improve patient outcomes with careful patient selection and intervention. The aim of this study is to examine the current applications of machine learning in cervical and lumbar degenerative spine disease. A systematic review was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A search of PubMed, Embase, Medline, and Cochrane was conducted through May 31st, 2020, using the following terms: "artificial intelligence" OR "machine learning" AND "neurosurgery" AND "spine." Studies were included if original research on machine learning was utilized in patient care for degenerative spine disease, including radiographic machine learning applications. Studies focusing on robotic applications in neurosurgery, navigation, or stereotactic radiosurgery were excluded. The literature search identified 296 papers, with 35 articles meeting inclusion criteria. There were nine studies involving cervical degenerative spine disease and 26 studies on lumbar degenerative spine disease. The majority of studies for both cervical and lumbar spines utilized machine learning for the prediction of postoperative outcomes, with 5 (55.6%) and 15 (61.5%) studies, respectively. Machine learning applications focusing on degenerative lumbar spine greatly outnumber the current volume of cervical spine studies. The current research in lumbar spine also demonstrates more advanced clinical applications of radiographic, diagnostic, and predictive machine learning models.

Long-term outcomes of spinal ependymomas: an institutional experience of more than 60 cases.

PURPOSE: Spinal ependymomas represent the most common primary intramedullary tumors for which optimal management remains undefined. When possible, gross total resection (GTR) is often the mainstay of treatment, with consideration of radiotherapy (RT) in cases of residual or recurrent tumor. The impact of extent of resection and radiotherapy remain understudied. OBJECTIVE: Report on a large institutional cohort with lengthy follow-up to provide information on long-term outcomes and to contribute to limited data assessing the value of extent of resection and RT. METHODS: Patients with pathologically proven primary spinal ependymoma between 1990 and 2018 were identified. Kaplan-Meier estimates were used to calculate progression-free survival (PFS); local-control (LC) and overall survival (OS). Logistic regression was used to analyze variables' association with receipt of RT. RESULTS: We identified 69 patients with ependymoma of which 4 had leptomeningeal dissemination at diagnosis and were excluded. Of the remaining cohort (n = 65), 42 patients (65%) had Grade II spinal ependymoma, 20 (31%) had Grade I myxopapillary ependymoma and 3 (5%) had Grade III anaplastic ependymoma; 54% underwent GTR and 39% underwent RT. With a median follow-up of 5.7 years, GTR was associated with improved PFS. For grade II lesions, STR+RT yielded better outcomes than STR alone (10y PFS 77.1% vs 68.2%, LC 85.7% vs 50%). Degree of resection was the only significant predictor of adjuvant radiotherapy (p < 0.0001). CONCLUSION: Our findings confirm the importance of GTR in spinal ependymomas. Adjuvant RT should be utilized in the setting of a subtotal resection with expectation of improved disease-related outcomes.

Assessing the spatial distribution of cervical spinal cord activity during tactile stimulation of the upper extremity in humans with functional magnetic resonance imaging.

Dermatomal maps are a mainstay of clinical practice and provide information on the spatial distribution of the cutaneous innervation of spinal nerves. Dermatomal deficits can help isolate the level of spinal nerve root involvement in spinal conditions and guide clinicians in diagnosis and treatment. Dermatomal maps, however, have limitations, and the spatial distribution of spinal cord sensory activity in humans remains to be quantitatively assessed. Here we used spinal cord functional MRI to map and quantitatively compare the spatial distribution of sensory spinal cord activity during tactile stimulation of the left and right lateral shoulders (i.e. C5 dermatome) and dorsal third digits of the hands (i.e., C7 dermatome) in healthy humans (n â€‹= â€‹24, age â€‹= â€‹36.8 â€‹± â€‹11.8 years). Based on the central sites for processing of innocuous tactile sensory information, we hypothesized that the activity would be localized more to the ipsilateral dorsal spinal cord with the lateral shoulder stimulation activity being localized more superiorly than the dorsal third digit. The findings demonstrate lateralization of the activity with the left- and right-sided stimuli having more activation in the ipsilateral hemicord. Contradictory to our hypotheses, the activity for both stimulation sites was spread across the dorsal and ventral hemicords and did not demonstrate a clear superior-inferior localization. Instead, the activity for both stimuli had a broader than expected distribution, extending across the C5, C6, and C7 spinal cord segments. We highlight the complexity of the human spinal cord neuroanatomy and several sources of variability that may explain the observed patterns of activity. While the findings were not completely consistent with our a priori hypotheses, this study provides a foundation for continued work and is an important step towards developing normative quantitative spinal cord measures of sensory function, which may become useful objective MRI-based biomarkers of neurological injury and improve the management of spinal disorders.

Impact of CrossFit-Related Spinal Injuries.

INTRODUCTION: Exercise-related injuries (ERIs) are a common cause of nonfatal emergency department and hospital visits. CrossFit is a high-intensity workout regimen whose popularity has grown rapidly. However, ERIs due to CrossFit remained under investigated. METHODS: All patients who presented to the main hospital at a major academic center complaining of an injury sustained performing CrossFit between June 2010 and June 2016 were identified. Injuries were classified by anatomical location (eg, knee, spine). For patients with spinal injuries, data were collected including age, sex, body mass index (BMI), CrossFit experience level, symptom duration, type of symptoms, type of clinic presentation, cause of injury, objective neurological examination findings, imaging type, number of clinic visits, and treatments prescribed. RESULTS: Four hundred ninety-eight patients with 523 CrossFit-related injuries were identified. Spine injuries were the most common injuries identified, accounting for 20.9%. Among spine injuries, the most common location of injury was the lumbar spine (83.1%). Average symptom duration was 6.4 months ± 15.1, and radicular complaints were the most common symptom (53%). A total of 30 (32%) patients had positive findings on neurologic examination. Six patients (6.7%) required surgical intervention for treatment after failing an average of 9.66 months of conservative treatment. There was no difference in age, sex, BMI, or duration of symptoms of patients requiring surgery with those who did not. CONCLUSIONS: CrossFit is a popular, high-intensity style workout with the potential to injure its participants. Spine injuries were the most common type of injury observed and frequently required surgical intervention.

Cervical sagittal balance: a biomechanical perspective can help clinical practice.

PURPOSE: In this article, we summarize our work on understanding the influence of cervical sagittal malalignment on the mechanics of the cervical spine. METHODS: Biomechanical studies were performed using an ex vivo laboratory model to study the kinematic and kinetic response of human cervical spine specimens in the setting of cervical sagittal imbalance. The model allowed controlled variations of C2-C7 Sagittal Vertical Alignment (C2-C7 SVA) and T1-Slope so that clinically relevant sagittally malaligned profiles could be prescribed, while maintaining horizontal gaze, and their biomechanical consequences studied. RESULTS: Our results demonstrated that increasing C2-C7 SVA caused flexion of lower cervical (C2-C7) segments and hyperextension of suboccipital (C0-C1-C2) segments to maintain horizontal gaze. An increase in C2-C7 SVA increased the lower cervical neural foraminal areas. Conversely, increasing T1-slope predominantly influenced subaxial cervical lordosis and, as a result, decreased cervical neural foraminal areas. Therefore, we believe patients with increased upper thoracic kyphosis and radicular symptoms may respond with increased forward head posture (FHP) as a compensatory mechanism to increase their lower cervical neural foraminal area and alleviate nerve root compression as well as reduce the burden on posterior muscles and soft and bony structures of the cervical spine. Increasing FHP (i.e., increased C2-C7 SVA) was associated with shortening of the cervical flexors and occipital extensors and lengthening of the cervical extensors and occipital flexors, which corresponds to C2-C7 flexion and C0-C2 extension. The greatest shortening occurred in the suboccipital muscles, suggesting considerable load bearing of these muscles during chronic FHP. Regardless, there was no evidence of nerve compression within the suboccipital triangle. Finally, cervical sagittal imbalance may play a role in exacerbating adjacent segment pathomechanics after multilevel cervical fusion and should be considered during surgical planning. CONCLUSIONS: The results of our biomechanical studies have improved our understanding of the impact of cervical sagittal malalignment on pathomechanics of the cervical spine. We believe this improved understanding will assist in clinical decision-making.

Dimensions of the cervical neural foramen in conditions of spinal deformity: an ex vivo biomechanical investigation using specimen-specific CT imaging.

PURPOSE: Patients with cervical spondylosis commonly present with neck pain, radiculopathy or myelopathy. As degenerative changes progress, multiple factors including disc height loss, thoracic kyphosis, and facetogenic changes can increase the risk of neural structure compression. This study investigated the impact of cervical deformity including forward head posture (FHP) and upper thoracic kyphosis, on the anatomy of the cervical neural foramen. METHODS: Postural changes of 13 human cervical spine specimens (Occiput-T1, age 50.6 years; range 21-67) were assessed in response to prescribed cervical sagittal malalignments using a previously reported experimental model. Two characteristics of cervical sagittal deformities, C2-C7 sagittal vertical alignment (SVA) and sagittal angle of the T1 vertebra (T1 tilt), were varied to create various cervical malalignments. The postural changes were documented by measuring vertebral positions and orientations. The vertebral motion data were combined with specimen-specific CT-based anatomical models, which allowed assessments of foraminal areas of subaxial cervical segments as a function of increasing C2-C7 SVA and changing T1 tilt. RESULTS: Increasing C2-C7 SVA from neutral posture resulted in increased neural foraminal area in the lower cervical spine (largest increase at C4-C5: 13.8 ± 15.7 %, P < 0.01). Increasing SVA from a hyperkyphotic posture (greater T1 tilt) also increased the neural foraminal area in the lower cervical segments (C5-C6 demonstrated the largest increase: 13.4 ± 9.6 %, P < 0.01). The area of the cervical neural foramen decreased with increasing T1 tilt, with greater reduction occurring in the lower cervical spine, specifically at C5-C6 (-8.6 ± 7.0 %, P < 0.01) and C6-C7 (-9.6 ± 5.6 %, P < 0.01). CONCLUSION: An increase in thoracic kyphosis (T1 tilt) decreased cervical neural foraminal areas. In contrast, an increase in cervical SVA increased the lower cervical neural foraminal areas. Patients with increased upper thoracic kyphosis may respond with increased cervical SVA as a compensatory mechanism to increase their lower cervical neural foraminal area.

Anatomy and biomechanics of the craniovertebral junction.

The craniovertebral junction (CVJ) has unique anatomical structures that separate it from the subaxial cervical spine. In addition to housing vital neural and vascular structures, the majority of cranial flexion, extension, and axial rotation is accomplished at the CVJ. A complex combination of osseous and ligamentous supports allow for stability despite a large degree of motion. An understanding of anatomy and biomechanics is essential to effectively evaluate and address the various pathological processes that may affect this region. Therefore, the authors present an up-to-date narrative review of CVJ anatomy, normal and pathological biomechanics, and fixation techniques.

Comparison of open and minimally invasive surgery for intradural-extramedullary spine tumors.

OBJECT Patients with symptomatic intradural-extramedullary (ID-EM) tumors may be successfully treated with resection of the lesion and decompression of associated neural structures. Studies of patients undergoing open resection of these tumors have reported high rates of gross-total resection (GTR) with minimal long-term neurological deficit. Case reports and small case series have suggested that these patients may be successfully treated with minimally invasive surgery (MIS). These studies have been limited by small patient populations. Moreover, there are no studies directly comparing perioperative outcomes between patients treated with open resection and MIS. The objective of this study was to compare perioperative outcomes in patients with ID-EM tumors treated using open resection or MIS. METHODS A retrospective review was performed using data collected from 45 consecutive patients treated by open resection or MIS for ID-EM spine tumors. These patients were treated over a 9-year period between April 2003 and October 2012 at Northwestern University and the University of Chicago. Statistical analysis was performed to compare perioperative outcomes between the two groups. RESULTS Of the 45 patients in the study, 27 were treated with the MIS approach and 18 were treated with the open approach. Operative time was similar between the two groups: 256.3 minutes in the MIS group versus 241.1 minutes in the open group (p = 0.55). Estimated blood loss was significantly lower in the MIS group (133.7 ml) compared with the open group (558.8 ml) (p < 0.01). A GTR was achieved in 94.4% of the open cases and 92.6% of the MIS cases (p = 0.81). The mean hospital stay was significantly shorter in the MIS group (3.9 days) compared with the open group (6.1 days) (p < 0.01). There was no significant difference between the complication rates (p = 0.32) and reoperation rates (p = 0.33) between the two groups. Multivariate analysis demonstrated an increased rate of complications in cervical spine tumors (OR 15, p = 0.05). CONCLUSIONS Thoracolumbar ID-EM tumors may be safely and effectively treated with either the open approach or an MIS approach, with an equivalent rate of GTR, perioperative complication rate, and operative time. Patients treated with an MIS approach may benefit from a decrease in operative blood loss and shorter hospital stays.

Evidence-based management of traumatic thoracolumbar burst fractures: a systematic review of nonoperative management.

OBJECT: The overall evidence for nonoperative management of patients with traumatic thoracolumbar burst fractures is unknown. There is no agreement on the optimal method of conservative treatment. Recent randomized controlled trials that have compared nonoperative to operative treatment of thoracolumbar burst fractures without neurological deficits yielded conflicting results. By assessing the level of evidence on conservative management through validated methodologies, clinicians can assess the availability of critically appraised literature. The purpose of this study was to examine the level of evidence for the use of conservative management in traumatic thoracolumbar burst fractures. METHODS: A comprehensive search of the English literature over the past 20 years was conducted using PubMed (MEDLINE). The inclusion criteria consisted of burst fractures resulting from a traumatic mechanism, and fractures of the thoracic or lumbar spine. The exclusion criteria consisted of osteoporotic burst fractures, pathological burst fractures, and fractures located in the cervical spine. Of the studies meeting the inclusion/exclusion criteria, any study in which nonoperative treatment was used was included in this review. RESULTS: One thousand ninety-eight abstracts were reviewed and 447 papers met inclusion/exclusion criteria, of which 45 were included in this review. In total, there were 2 Level-I, 7 Level-II, 9 Level-III, 25 Level-IV, and 2 Level-V studies. Of the 45 studies, 16 investigated conservative management techniques, 20 studies compared operative to nonoperative treatments, and 9 papers investigated the prognosis of conservative management. CONCLUSIONS: There are 9 high-level studies (Levels I-II) that have investigated the conservative management of traumatic thoracolumbar burst fractures. In neurologically intact patients, there is no superior conservative management technique over another as supported by a high level of evidence. The conservative technique can be based on patient and surgeon preference, comfort, and access to resources. A high level of evidence demonstrated similar functional outcomes with conservative management when compared with open surgical operative management in patients who were neurologically intact. The presence of a neurological deficit is not an absolute contraindication for conservative treatment as supported by a high level of evidence. However, the majority of the literature excluded patients with neurological deficits. More evidence is needed to further classify the appropriate burst fractures for conservative management to decrease variables that may impact the prognosis.

Incidence of lumbar spine pedicle breach after percutaneous screw fixation: a radiographic evaluation of 601 screws in 151 patients.

STUDY DESIGN: Prospective clinical study. OBJECTIVES: Although percutaneous pedicle screw fixation continues to be increasingly practiced, there remain few reports specifically addressing the accuracy and clinical safety of this technique. The goal of this study is to evaluate the accuracy of fluoroscopically guided pedicle screw placement in the lumbar spine. SUMMARY OF BACKGROUND DATA: Pedicle breach rates vary substantially in the literature. Pedicle breach rates have been reported to be as high as 29% with the traditional, open technique. With the use of computer-assisted 2-dimensional fluoroscopy, breach rates have been reported between 5% and 23%. Furthermore, in a series of 225 pedicles instrumented with 3-dimensional fluoroscopy, the reported breach rate was 1.8%. METHODS: A total of 151 patients were evaluated after instrumented single-level or 2-level minimally invasive transforaminal lumbar interbody fusion with 601 screws placed for percutaneous fixation. The treated patients had an average age of 56.6 y (20-85 y) and there were 129 cases of single-level and 22 cases of 2-level. The levels of pedicle screw fixation included (level, patient numbers): L1/L2 (1), L2/L3 (2), L3/L4 (33), L4/L5 (101), L5/S1 (46). Radiographic results included postoperative computed tomographic scan. Patients were followed prospectively for potential clinical symptoms. RESULTS: In a total of 601 instrumented pedicles, there were 37 pedicle breaches (6.2%). Of these, 22 (3.7%) were significant breaches (≥3 mm). The level of the breached pedicles were L3 (5/46, 10.2%), L4 (12/201, 7.0%), L5 (15/158, 9.5%), S1 (3/47, 3.4%). The side/location of breach was characterized as follows: medial (22), lateral (12), superior (2), and inferior (1). There were 2 symptomatic breaches, both associated with a medial breach at the L5 pedicle. Symptoms from these events were transient and did not require hardware repositioning. There were no other complications. CONCLUSIONS: Percutaneous pedicle screw fixation in the lumbar spine continues to be a technique embraced by modern spinal surgeons. The use of intraoperative fluoroscopic guidance is both a clinically safe and accurate method for instrumentation and is of comparable accuracy to other techniques. Although trajectory errors may occur, they are of rare clinical significance.

Distinct Time-Resolved Brain-Wide Coactivations in Oxygenated and Deoxygenated Hemoglobin.

OBJECTIVE: Human resting-state networks (RSNs) estimated from oxygenated (HbO) and deoxygenated hemoglobin (HbR) data exhibit strong similarities, while task-based studies show different dynamics in HbR and HbO responses. Such a discrepancy might be explained due to time-averaged estimations of RSNs. Our study investigated differences between HbO and HbR on time-resolved brain-wide coactivation patterns (CAPs). METHODS: Diffuse optical tomography was reconstructed from resting-state whole-head functional near-infrared spectroscopy data of HbR and HbO in individual healthy participants. Time-averaged RSNs were obtained using the group-level independent component analysis. Time-resolved CAPs were estimated using a clustering approach on the time courses of all obtained RSNs. Characteristics of the RSNs and CAPs from HbR and HbO were compared. RESULTS: Spatial patterns of HbR and HbO RSNs exhibited significant similarities. Meanwhile, HbR CAPs revealed much more organized spatial and dynamic characteristics than HbO CAPs. The entire set of HbR CAPs suggests a superstructure resulted from brain-wide neuronal dynamics, which is less evident in the set of HbO CAPs. These differences between HbO and HbR CAPs were consistently replicated in individual session data. CONCLUSION: Our results suggest that human resting brain-wide neuronal activations are preserved better in time-resolved brain-wide patterns, i.e., CAPs, from HbR than those from HbO, while such a difference is lost between time-averaged HbR and HbO RSNs. SIGNIFICANCE: Our results reveal, for the first time, HbR concentration fluctuations are more directly coupled with resting dynamics of brain-wide neuronal activations in human brains.

Surgical management of spinal pathologies in the octogenarian: a narrative review.

Optimal management paradigms of spinal pathologies in the octogenarian population are controversial given the higher incidence of comorbidities with concern for poor prognosis and fear of increased complications associated with surgical management. In this narrative review, we aim to detail the complex clinical considerations when approaching odontoid screw fixation/instrumented fusion, spinal decompression, and spinal fusion in the octogenarian. Literature review was conducted via Google Scholar and PubMed databases, with literature selected based on statistical power and clinical relevance to the following pathologies/surgical techniques: odontoid fracture, surgical decompression, and surgical fusion in the octogenarian. The aforementioned pathologies were selected based on prevalence in the advanced-age population in which surgical screening techniques and management remain nonuniform. Preoperative evaluation of the octogenarian patient increasingly includes frailty, sarcopenia, and osteopenia/osteoporosis assessments. In cases of odontoid fracture, conservative management appears to provide beneficial clinical outcomes with lower rates of complication compared to surgery; however, rates of radiographic odontoid fusion are far lower in conservatively managed patients. Regarding surgical decompression and fusion, the presence of comorbidities may be more predictive of outcome rather than age status, with the advent of minimally invasive techniques providing safety and efficacy in the surgical management of this age cohort. Age status may be less pertinent than previously thought in the decision to pursue spinal surgery for odontoid fracture, spinal decompression, or spinal fusion; however, each of these procedures has respective risks and benefits that must be considered within the context of each patient's comorbidity profile.

Degenerative cervical myelopathy: establishing severity thresholds for neuromotor dysfunction in the aging spine using the NIH Toolbox Assessment Scale.

Degenerative cervical myelopathy (DCM) is a leading cause of age-related non-traumatic spinal cord disorders resulting from chronic degeneration of the cervical spine. While traditional clinical assessments rely on patient-reported measures, this study used the NIH Toolbox Motor Battery (NIHTBm) as an objective, quantitative measure to determine DCM severity. The objective is to define NIHTBm cutoff values that can accurately classify the severity of DCM neuromotor dysfunction. A case-controlled pilot study of patients with DCM and age-matched controls. The focus was an in-depth quantitative motor assessment using the NIHTBm to understand the severity of neuromotor deficits due to degenerative spine disease. Motor assessments, dexterity, grip strength, balance, and gait speed were measured in 45 DCM patients and 37 age-matched healthy subjects (HC). Receiver operating curve (ROC) analysis determined cutoff values for mild and moderate-to-severe myelopathy which were validated by comparing motor assessment scores with disability scores. The ROC curves identified thresholds for mild dexterity impairment (T-score range 38.4 - 33.5, AUC 0.77), moderate-to-severe dexterity impairment (< 33.5, AUC 0.70), mild grip strength impairment (47.4 - 32.0, AUC 0.80), moderate-to-severe grip strength impairment (< 32.0, AUC 0.75), mild balance impairment (36.4 - 33.0, AUC 0.61), and moderate-to-severe balance impairment (< 33.0, AUC 0.78). Mild gait speed impairment was defined as 0.78-0.6 m/sec (AUC 0.65), while moderate-to-severe gait speed impairment was < 0.6 m/sec (AUC 0.65). The NIHTB motor score cutoff points correlated negatively with the DCM neck disability index (NDI) and showed balance and dexterity measures as independent indicators of DCM dysfunction. The use of NIHTB allows for precise delineation of DCM severity by establishing cutoff values corresponding to mild and moderate-to-severe myelopathy. The use of NIHTB in DCM allows enhanced clinical precision, enabling clinicians to better pinpoint specific motor deficits in DCM and other neurological disorders with motor deficits, including stroke and traumatic brain injury (TBI). Furthermore, the utility of objective assessment, NIHTB, allows us to gain a better understanding of the heterogeneity of DCM, which will enhance treatment strategies. This study serves as a foundation for future research to facilitate the discovery of innovative treatment strategies for DCM and other neurological conditions.

Evaluating osteoporosis and bone quality in the aging spine: modern considerations for surgical management in the geriatric population.

Surgical management paradigms of spinal pathologies in the aging population carry inherent substantial risks, with surgical complications being more prevalent among patients with osteoporosis compared to those with normal bone mineral density. In this narrative review, we aim to highlight important clinical understanding and considerations in perioperative evaluation and management of patients elected to undergo spinal surgery. Osteoporosis is a well-defined risk factor for mechanical complications following spinal surgery, and as such, perioperative optimization of bone health in the setting of surgery for geriatric patients remains a critical research area alongside intraoperative surgical augmentation techniques. Surgical techniques to circumvent challenges with instrumentation of poor bone mineral density have included augmentation of pedicle screw fixation, including segmental bicortical screw fixation techniques, cement augmentation with fenestrated screws, or use of expandable pedicle screws to improve bone-implant interface. Judicious selection of treatment modalities and subsequent perioperative optimization is paramount to minimize surgical complications. Contemporary guidelines and evolving paradigms in perioperative evaluation, optimization, and management of the aging spine include the advent of quantitatively evaluating computed tomography (CT) via assessment of the magnitude of Hounsfield units. Prescribing pharmacotherapeutic agents and monitoring bone health requires a multidisciplinary team approach, including endocrinologists and geriatricians to coordinate high-quality care for advanced-age patients who require surgical management of their spinal disorders.

Early neurological changes in aging cervical spine: insights from PROMIS mobility assessment.

Many studies have shown that the prevalence of degenerative spinal cord compression increases with age. However, most cases at early stages are asymptomatic, and their diagnosis remains challenging. Asymptomatic cervical spinal cord compression (ASCC) patients are more likely to experience annular tears, herniated disks, and later develop symptomatic compression. Asymptomatic individuals do not typically undergo spinal cord imaging; therefore, an assessment test that is both sensitive and specific in diagnosing ASCC may be helpful. It has been demonstrated that the Patient Reported Outcome Measure Information System (PROMIS) mobility test is sensitive in detecting degenerative cervical myelopathy (DCM) symptoms. We investigated the use of the PROMIS mobility test in assessing clinical dysfunction in ASCC. In this study, 51 DCM patients and 42 age-matched healthy control (HC) were enrolled. The degree of cervical spinal cord compression was assessed using the high-resolution cervical spinal cord T2 Weighted (T2w) MRIs, which were available for 14 DCM patients. Measurements of the spinal cords anterior-posterior (AP) diameter at the region(s) that were visibly compressed as well as at different cervical spine levels were used to determine the degree of compression. The age-matched HC cohort had a similar MRI to establish the normal range for AP diameter. Twelve (12) participants in the HC cohort had MRI evidence of cervical spinal cord compression; these individuals were designated as the ASCC cohort. All participants completed the PROMIS mobility, PROMIS pain interference (PI), PROMIS upper extremity (UE), modified Japanese orthopedic association (mJOA), and neck disability index (NDI) scoring scales. We examined the correlation between the AP diameter measurements and the clinical assessment scores to determine their usefulness in the diagnosis of ASCC. Furthermore, we examine the sensitivity and specificity of PROMIS mobility test and mJOA. Compared to the HC group, the participants in the ASCC and DCM cohorts were significantly older (p = 0.006 and p < 0.0001, respectively). Age differences were not observed between ASCC and DCM (p > 0.999). Clinical scores between the ASCC and the HC group were not significantly different using the mJOA (p > 0.99), NDI (p > 0.99), PROMIS UE (p = 0.23), and PROMIS PI (p = 0.82). However, there were significant differences between the ASCC and HC in the PROMIS mobility score (p = 0.01). The spinal cord AP diameter and the PROMIS mobility score showed a significant correlation (r = 0.44, p = 0.002). Decreasing PROMIS mobility was significantly associated with a decrease in cervical spinal cord AP diameter independent of other assessment measures. PROMIS mobility score had a sensitivity of 77.3% and specificity of 79.4% compared to 59.1% and 88.2%, respectively, for mJOA in detecting cervical spinal cord compression. Certain elements of ASCC are not adequately captured with the traditional mJOA and NDI scales used in DCM evaluation. In contrast to other evaluation scales utilized in this investigation, PROMIS mobility score shows a significant association with the AP diameter of the cervical spinal cord, suggesting that it is a sensitive tool for identifying early disability associated with degenerative change in the aging spine. In a comparative analysis of PROMIS mobility test against the standard mJOA, the PROMIS mobility demonstrated higher sensitivity for detecting cervical spinal cord compression. These findings underscore the potential use of PROMIS mobility score in clinical evaluation of the aging spine.

Systematic review protocol for complications following surgical decompression of degenerative cervical myelopathy.

BACKGROUND: Degenerative Cervical Myelopathy (DCM) is one of the most common degenerative disorders of cervical spine and sources of cord dysfunction in adults. It usually manifests with neurologic presentations such as loss of dexterity and gait issues. Treatment for moderate and severe cases of DCM is surgical decompression of the region. There are many approaches available for surgical intervention which could be categorized into anterior and posterior based on the side of neck where operation takes place. Additionally, for certain cases the hybridized anterior-posterior combined surgery is indicated. While there are many technical differences between these approaches with each having its own advantages, the complications and safety profiles of them are not fully disclosed. This protocol aims to systematically search for current reports on complications of surgical decompression methods of DCM and pool them for robust evidence generation. METHOD: Search will be carried out in PubMed, Scopus, and Cochrane databases for retrospective and prospective surgical series, cohorts, or trials being performed for DCM with at least a sample size of 20 patients. Query strings will be designed to capture reports with details of complications with no year limit. Studies not being original (e.g., review articles, case reports, etc.), not in English, having patients younger than 18-years-old, and not reporting at least one complication will be excluded. Two independent reviewers will review the titles and abstracts for first round of screening. Full text of retrieved studies from previous round will be screened again by the same reviewers. In case of discrepancy, the third senior reviewer will be consulted. Eligible studies will then be examined for data extraction where data will be recorded into standardized form. Cumulative incidence and 95% confidence intervals of complication will be then pooled based on generalized linear mixed models with consideration of approach of surgery as subgroups. Heterogeneity tests will be performed for assessment of risk of bias. DISCUSSION: This systematic review is aimed at providing practical information for spine surgeons on the rates of complications of different surgical approaches of DCM decompression. Proper decision-making regarding the surgical approach in addition to informing patients could be facilitated through results of this investigation.

Post-pandemic paradigm shift toward telemedicine and tele-education; an updated survey of the impact of Covid-19 pandemic on neurosurgery residents in United States.

Background: Several strategies were implemented during the Covid-19 pandemic to enhance residency training and patient care. Objective: This study aims to assess the post-pandemic landscape of neurosurgical training and practice. Method: A survey consisting of 28 questions examining the challenges faced in neurosurgery and the adaptive measures was conducted among US neurosurgery residents from May 2022 to May 2023. Results: This study encompassed 59 neurosurgical residents, predominantly male (72.9%) and in later years of training (66.1%) and were distributed across 25 states. Telemedicine and tele-education were pivotal during the pandemic, with virtual lecture series, standalone lectures, and virtual discussions highly favored. Remote didactic learning increased for nearly half of the residents, while 54.2% resumed in-person instruction. Telemedicine was deemed effective by 86.4% for evaluating neurosurgical patients. Access to teaching environments was restricted for 61.0% of residents, impacting their training. The pandemic significantly influenced elective surgeries, with complete cancellations reported by 42.4%. Reduced faculty engagement was noted by 35.6% of residents, while 47.5% reported a negative impact on the overall resident experience. The majority (76.3%) considered changes to their training reasonable given the global health situation. Conclusions: Strategies implemented during the peak of the pandemic remain crucial in shaping neurosurgery training. Telemedicine has become indispensable, with widespread adoption. Tele-education has also expanded, providing additional learning opportunities. However, traditional didactic courses and hands-on experiences remain essential for comprehensive training. Balancing technology-driven methods with established approaches is crucial for optimizing neurosurgical education and maintaining high-quality patient care.

Cervical Spinal Cord Morphometrics in Degenerative Cervical Myelopathy: Quantification using Semi-automated Normalized Technique and Correlation with Neurological Dysfunctions.

BACKGROUND CONTEXT: Degenerative cervical myelopathy (DCM) is characterized by spinal cord atrophy. Accurate estimation of spinal cord atrophy is key to the understanding of neurological diseases, including DCM. However, its clinical application is hampered by difficulties in its precise and consistent estimation due to significant variability in spinal cord morphometry along the cervical spine, both within and between individuals. PURPOSE: To characterize morphometrics of the compressed spinal cord in DCM patients. We employed our semi-automated analysis framework that incorporates the Spinal Cord Toolbox (SCT) and a normalization approach to effectively address the challenges posed by cord compression in these patients. Additionally, we examined the clinical relevance of these morphometric measures to enhance our understanding of DCM pathophysiology. STUDY DESIGN: Prospective study. PATIENT SAMPLE: This study investigated 36 DCM patients and 31 healthy controls (HCs). OUTCOME MEASURES: Clinical scores including 9-hole peg test for hand dexterity, hand grip strength, balance, gait speed, modified Japanese Orthopaedic Association (mJOA) score, and imaging-based spinal cord morphometrics. METHOD: Using the generic spine acquisition protocol and our semi-automated analysis pipeline, spinal cord morphometrics, including cross-sectional area (CSA), anterior-posterior (AP) and transverse (RL) diameters, eccentricity, and solidity, were estimated from sagittal T2w magnetic resonance imaging (MRI) images using the Spinal Cord Toolbox (SCT). Normalized metrics were extracted from the C1 to C7 vertebral levels and compared between DCM patients and HC. Morphometric data at regions of maximum spinal cord compression (MSCC) were correlated with the clinical scores. A subset of participants underwent follow-up scans at six months to monitor longitudinal changes in spinal cord atrophy. RESULTS: Spinal cord morphometric data were normalized against the healthy population morphometry (PAM50 database) and extracted for all participants. DCM patients showed a notable reduction in CSA, AP, and RL diameter across all vertebral levels compared to HC. MSCC metrics correlated significantly with clinical scores like dexterity, grip strength, and mJOA scores. Longitudinal analysis indicated a decrease in CSA and worsening clinical scores in DCM patients. CONCLUSION: Our processing pipeline offers a reliable method for assessing spinal cord compression in DCM patients. Normalized spinal cord morphometrics, particularly the CSA could have potential for monitoring DCM disease severity and progression, guiding treatment decisions. Furthermore, to our knowledge our study is the first to apply the generic spinal cord acquisition protocol, ensuring consistent imaging across different MRI scanners and settings. Coupled with our semi-automated analysis pipeline, this protocol is key for the detailed morphometric characterization of compressed spinal cords in patients with DCM, a disease that is both complex and heterogenous. This study was funded by the National Institute of Neurological Disorders and Stroke (NINDS) (K23:NS091430) and (R01: NS129852-01A1).