Faculty Bibliography

BACKGROUND AND OBJECTIVES/OBJECTIVE:The rapid rise of electric and mechanical bikes and scooters has transformed urban transportation, but their neurosurgical consequences remain underexplored. This study aimed to evaluate micromobility-related injuries over time, examining mechanisms of injury, patient risk factors, injury patterns, and associated clinical outcomes at a Level-1 trauma center over a 5-year period. METHODS:We performed a retrospective review of patients who sustained micromobility-related injuries and presented to the Bellevue Hospital Center between 2018 and 2023. The cohort included riders of electric or mechanical bikes and scooters, as well as pedestrians struck by these devices. Key clinical variables and outcomes were compared across device types, both before and after propensity score matching. Unlike national database studies, this hospital-based analysis provides detailed clinical and neurosurgical outcome data. RESULTS:A total of 914 patients presented with micromobility-related injuries, accounting for 6.9% of all trauma admissions. Annual case volume and electric device involvement increased over time. The most common mechanism was collision with a motor vehicle (49.9%). Most patients (68.7%) required admission; 30.2% required intensive care. The median length of hospital stay was 3 days [IQR 1-5]. Half underwent a surgical intervention or procedure, and the overall mortality was 1.2%. Helmet use was low (31.7%). Pedestrians experienced the most severe outcomes, particularly when struck by electric devices. Injuries clustered during evening hours, suggesting modifiable environmental and behavioral risk factors. CONCLUSION/CONCLUSIONS:Micromobility-related trauma imposes a substantial neurosurgical burden, with frequent traumatic brain injury, intensive care unit utilization, and operative intervention. Unlike previous database studies, this hospital-based analysis provides detailed neurosurgical outcome data and identifies prevention targets-including helmet use, intoxication, and urban infrastructure-to reduce morbidity and resource utilization.

OBJECTIVE:Management of locally invasive colorectal carcinoma at any stage currently involves surgical excision followed by chemoradiotherapy; however, the prognosis is poor, with a 5-year overall survival (OS) of only 5%. Failure to achieve gross-total resection is associated with poorer OS, and patients with residual tumor postresection (R1 or R2 resection) have a median OS of 7 months compared with 23 months in those who undergo resection with negative margins (R0 resection). For tumors that have invaded the sacrum, sacrectomy becomes necessary to achieve R0 resection. The objective of this study was to provide a descriptive multicenter account of resection for locally invasive colorectal carcinoma with sacral invasion, focusing on the association of tumor morphometry with surgical planning and perioperative outcomes. METHODS:Demographic, comorbidity, clinical, tumor-specific, operative characteristic, and outcome data were collected on all patients who underwent resection of colorectal carcinoma with concurrent sacral resection between January 2005 and May 2022. Patients were grouped into those having undergone surgery for purely palliative intent, or those with resection with attempt at local control and dichotomized into level of osteotomy (either proximal or distal to the S2-3 level). RESULTS:Twenty-two patients (median age 50.5 [IQR 43.3-60.0] years, 54.5% female) underwent sacrectomy for colorectal carcinoma. Operative records indicated intent for local control in 14 patients and palliative in the remaining 8 patients. Palliative surgical intent was based primarily on the presence of distant metastases. There was no significant difference in median local progression-free survival between patients undergoing osteotomy proximal to the S2-3 level and those undergoing osteotomy distal to the S2-3 level. CONCLUSIONS:En bloc resection is believed to offer the best local control in patients with locally invasive colorectal carcinoma. The present descriptive series highlights outcomes of en bloc resection with partial or full sacrectomy in patients with tumors showing local extension into the sacrum. Complications are common, most often in the form of wound dehiscence or infection, and many patients require placement in a rehabilitation or intermediate-care facility upon discharge. However, for those with stage III (locally aggressive) disease, median OS exceeds 16 years, suggesting that such aggressive management with en bloc resection may be warranted in properly selected patients.

OBJECTIVE:Tethered cord syndrome (TCS) is a significant cause of debilitation in patients with spinal dysraphisms or tumors. Management of TCS has historically centered on intradural detethering surgery, which is associated with a substantial risk of retethering, symptom recurrence, and repeat surgery. Vertebral column resection (VCR) has recently gained popularity as a treatment option via spinal shortening, but the literature on long-term outcomes is sparse. The objective of this study was to explore long-term clinical outcomes in a series of patients undergoing VCR for recurrent TCS. METHODS:A retrospective review was conducted of all consecutive patients undergoing VCR for recurrent TCS at a single center between 2014 and 2024. Demographic and radiological characteristics were recorded, including spinal column height reduction as well as symptom improvement rates regarding sensorimotor dysfunction, pain, and incontinence at the latest follow-up. Intra- and postoperative complications were noted, and pre- and postoperative symptomology was compared using McNemar's test at a significance level of p < 0.05 to identify improvements. RESULTS:Twenty surgeries in 19 patients (median age 19 years) involving 10 males (52.6%) were assessed. The most common etiology of TCS was lipomyelomeningocele (n = 7, 36.8%), followed by lipoma (n = 6, 31.6%). Patients underwent a mean of 3.4 previous detethering procedures. Osteotomy was most commonly performed at the L1 level (n = 11, 55.0%), and the mean spinal column height reduction was 16.5 mm. At a mean follow-up of 43.1 (range 12-101) months, resolution of symptoms was observed in 10 patients with back pain (71.4%; p = 0.043), 10 patients with leg pain (66.7%; p = 0.004), 9 patients with lower extremity weakness (75.0%; p = 0.008), 4 patients with urinary incontinence (44.4%; p = 0.371), and 1 patient with fecal incontinence (33.3%; p > 0.99). Complications included a CSF leak in 1 patient and repeat VCR in 1 patient. CONCLUSIONS:These results suggest that in select patients with recurrent TCS, VCR represents a treatment option with high rates of symptomatic improvement and a relatively low risk of retethering as observed over several years of follow-up. These results add to the body of literature supporting VCR and provide a compelling basis for future prospectively designed studies.

PURPOSE/UNASSIGNED:Direct-wave (D-wave) neuromonitoring is a direct measure of corticospinal tract integrity that detects potential injury during spinal cord surgery. Epidural placement of electrodes used for D-wave measurements can result in high electrical impedances resulting in substantial signal noise that can compromise signal interpretation. Subdural electrode placement may offer a solution. METHODS:Medical records for consecutive patients with epidural and subdural D-wave monitoring were reviewed. Demographic and clinical information including preoperative and postoperative motor strength were recorded. Neuromonitoring charts were reviewed to characterize impedances and signal amplitudes of D-waves recorded epidurally (before durotomy) and subdurally (following durotomy). Nonparametric statistics were used to compare epidural and subdural D-waves. RESULTS:Ten patients (50% women, median age 50.5 years) were analyzed, of which five patients (50%) were functionally independent (modified McCormick grade ≤ II) preoperatively. D-waves were successfully acquired by subdural electrodes in eight cases and by epidural electrodes in three cases. Subdural electrode placement was associated with lower impedance values ( P = 0.011) and a higher baseline D-wave amplitude ( P = 0.007) relative to epidural placement. No association was observed between D-wave obtainability and functional status, and no adverse events relating to subdural electrode placement were encountered. CONCLUSIONS:Subdural electrode placement allows successful D-wave acquisition with accurate monitoring, clearer waveforms, and a more optimal signal-to-noise ratio relative to epidural placement. For spinal surgeries where access to the subdural compartment is technically safe and feasible, surgeons should consider subdural placement when monitoring D-waves to optimize clinical interpretation.

BACKGROUND:ChatGPT is a natural language processing chatbot with a significant prevalence in modern media with a clear application in the medical triage workflow. ChatGPT has shown significant capacity for understanding clinical vignettes, radiology reports, and even passing the American Board of Neurological Surgery board examination. There has never been an evaluation of the chatbot in triage and diagnosing spinal vignettes common to primary and urgent care practice. METHODS:Fifteen clinical scenarios were created to mimic spinal complaints common to primary and urgent care scenarios. GPT-4 was instructed to assess the situation as if it was in a primary care office and determine diagnosis, imaging recommendations, and if emergency room (ER) or operative referral was necessary. Answers were recorded and the results compared to those of attending and resident respondents. RESULTS:GPT-4 provided the most likely diagnosis in each scenario. Additionally, it recommended reasonable clinical management of each scenario which would fall within standard practice guidelines. ChatGPT tended toward over-referral to the ER; however, this was not significant. GPT-4 was noninferior in all categories when compared to respondents. CONCLUSIONS:ChatGPT is a powerful tool for primary triage of spinal issues. It can rapidly and accurately evaluate clinical scenarios and provide clear diagnostic reasoning. GPT-4 is not designed for medical use and will provide a disclaimer as such. It did tend toward over-referring patients to the ER. With specific training, it is likely that artificial intelligence and natural language processing chatbots will become widely used in primary triage of spinal issues.

BACKGROUND AND OBJECTIVES/OBJECTIVE:Communication has a well-established effect on improving outcomes. The current study evaluated the effect of multidisciplinary preoperative team communication using a digital huddle software platform on operating room costs. METHODS:A digital huddle software platform was implemented in March 2022 for neurosurgical procedures performed at a single tertiary care center. Surgeons were encouraged, but not required, to participate. General linear models were used to test the association between participation and the difference in supply-related cost and case length, using intergroup comparison and historical controls. RESULTS:A total of 29626 cases (performed by 97 surgeons), conducted between March 2021 and June 2023, were included in our analysis. Cases from participating neurosurgeons (12 surgeons, 4064 cases) were compared with cases from nonparticipating neurosurgeons (6 surgeons, 2452 cases), non-neurosurgery cases carried out by the same operating room staff (20 orthopedic spine surgeons, 6073 cases), and non-neurosurgery cases performed in a different operating room unit (59 surgeons, 21 996 cases). In aggregate, operating room (OR) costs increased by 7.3% (95% CI: 0.9-14.1, P = .025) in the postintervention period. In the same period, participation in the digital huddle platform was associated with an OR utilization and supply-related cost decrease of 16.3% (95% CI: 8.3%-23.6%, P < .001). Among neurosurgeons specifically, participation was associated with a supply-related cost decrease of 17.5% (95% CI: 6.0%-27.5%, P = .0037). There was no change in case length (median case length 171 minutes, change: +2.7% increase, 95% CI:-2.2%-7.9%, P = .28). CONCLUSION/CONCLUSIONS:The implementation of a digital huddle software platform resulted in an OR utilization and supply cost decrease among participants during a period when the overall nonparticipating control cohort experienced an increase in cost.

PURPOSE/OBJECTIVE:Postoperative bowel and bladder dysfunction (BBD) poses a significant risk following surgery of the sacral spinal segments and sacral nerve roots, particularly in neuro-oncology cases. The need for more reliable neuromonitoring techniques to enhance the safety of spine surgery is evident. METHODS:We conducted a case series comprising 60 procedures involving 56 patients, spanning from September 2022 to January 2024. We assessed the diagnostic accuracy of sacral reflexes (bulbocavernosus and external urethral sphincter reflexes) and compared them with transcranial motor evoked potentials (TCMEP) incorporating anal sphincter (AS) and external urethral sphincter (EUS) recordings, as well as spontaneous electromyography (s-EMG) with AS and EUS recordings. RESULTS:Sacral reflexes demonstrated a specificity of 100% in predicting postoperative BBD, with a sensitivity of 73.33%. While sensitivity slightly decreased to 64.71% at the 1-month follow-up, it remained consistently high overall. TCMEP with AS/EUS recordings did not identify any instances of postoperative BBD, whereas s-EMG with AS/EUS recordings showed a sensitivity of 14.29% and a specificity of 97.14%. CONCLUSION/CONCLUSIONS:Sacral reflex monitoring emerges as a robust adjunct to routine neuromonitoring, offering surgeons valuable predictive insights to potentially mitigate the occurrence of postoperative BBD.

INDICATIONS CORRIDOR AND LIMITS OF EXPOSURE/UNASSIGNED:The extreme lateral approach is useful for both extradural and intradural anterior and anterolateral lesions at the lower clivus down to the level of C2. ANATOMIC ESSENTIALS NEED FOR PREOPERATIVE PLANNING AND ASSESSMENT/UNASSIGNED:The patient is evaluated with MRI, computed tomography (CT), and an angiogram. Special attention is given to vascular (vertebral artery course, dominance, tumor feeders) and bony (occipital condyle, jugular tubercle, foramen magnum and extent of bony involvement) anatomy. ESSENTIALS STEPS OF THE PROCEDURE/UNASSIGNED:The patient is positioned lateral with the head flexed and tilted down without axial rotation. A hockey-stick incision is performed, and the myocutaneous flap is raised. A retrocondylar craniectomy is performed. The extradural vertebral artery is exposed for proximal control. A C1 hemilaminectomy is performed. Cephalad/caudal exposure and drilling of the occipital condyle are determined per case. The dura is opened, and the vertebral artery is released at the dural entry point to facilitate the tumor removal. The tumor is debulked and delivered inferoventrally away from the neuroaxis and cranial nerves. After removing the tumor, the dura is closed using an allograft.The patients consented to the procedure and to the publication of their images. PITFALLS/AVOIDANCE OF COMPLICATIONS/UNASSIGNED:• Cranial nerve deficits• Craniocervical instability• Postoperative hydrocephalus• Postoperative pseudomeningocele. VARIANTS AND INDICATIONS FOR THEIR USE/UNASSIGNED:A transmastoid extension of the craniectomy allows access further rostrally in the clivus. For C1-2 chordomas, the approach is extended inferiorly, and the vertebral artery is mobilized out of the C1-2 transverse foramina. For tumors involving the joints, an occipitocervical stabilization is required.Images in video reused with permission as follows: image at 00:16 from Revuelta Barbero et al, Endoscopic endonasal transclival-medial condylectomy approach for resection of a foramen magnum meningioma: 2-dimensional operative video, Oper Neurosurg, 16(2), 2018, by permission from the Congress of Neurological Surgery; images at 00:30, and top image at 00:52 reused from Wen et al, Microsurgical anatomy of the transcondylar, supracondylar, and paracondylar extensions of the far-lateral approach, J Neurosurg, 87(4), 1997, with permission from JNSPG; bottom images at 00:52 from Muthukumar et al, A morphometric analysis of the foramen magnum region as it relates to the transcondylar approach, Acta Neurochir, 147(8), 2005, by permission from Springer Nature.

Over the past generation, outcome measures in spine care have evolved from a reliance on clinician-reported assessment toward recognizing the importance of the patient's perspective and the wide incorporation of patient-reported outcomes (PROs). While patient-reported outcomes are now considered an integral component of outcomes assessments, they cannot wholly capture the state of a patient's functionality. There is a clear need for quantitative and objective patient-centered outcome measures. The pervasiveness of smartphones and wearable devices in modern society, which passively collect data related to health, has ushered in a new era of spine care outcome measurement. The patterns emerging from these data, so-called "digital biomarkers," can accurately describe characteristics of a patient's health, disease, or recovery state. Broadly, the spine care community has thus far concentrated on digital biomarkers related to mobility, although the researcher's toolkit is anticipated to expand in concert with advancements in technology. In this review of the nascent literature, we describe the evolution of spine care outcome measurements, outline how digital biomarkers can supplement current clinician-driven and patient-driven measures, appraise the present and future of the field in the modern era, as well as discuss present limitations and areas for further study, with a focus on smartphones (see Supplemental Digital Content , http://links.lww.com/NEU/D809 , for a similar appraisal of wearable devices).