Akinduro, Oluwaseun O.

Management of unstable upper lumbar fractures with corpectomy and posterior fixation is technically demanding, and conventional workflows may require intraoperative repositioning, increasing operative complexity. Lateral mini-open upper lumbar corpectomy (LMULC) paired with robotic-assisted (RA) posterior percutaneous pedicle screw fixation (PPPSF) can be performed in a single position to facilitate ventral spinal decompression and stabilization in the anatomically constrained upper lumbar spine. In this study, we describe the operative technique and report four illustrative cases of unstable L1 or L2 fractures treated with single-position LMULC, RA-PPPSF, and short-segment fusion. Clinical, radiological, intraoperative variables and postoperative outcomes were evaluated. The mean age was 52.3 ± 17.7 years. The median operation time was 314 min (range 268–361 min); the median estimated blood loss (EBL) was 225 mL (range 100–400 mL). The median preoperative kyphosis was 10.15° (range 8.4–14.6°), the median postoperative kyphosis measured 6.65° (range 1.7–10.8°) and the median correction achieved was 3.5° (range −2.4–12.9°). The median visual analog scale (VAS) pain score reduced from 7 (range 7–9) preoperatively to 4.5 (range 2–6) postoperatively at discharge. At a median follow-up of 12 months (range 6–15 months), all patients had uncomplicated recoveries, demonstrated solid fusion on imaging, and reported favorable MacNab outcomes. Single-position LMULC with RA-PPPSF was technically feasible in this preliminary illustrative series and resulted in favorable clinical and radiographic outcomes. However, further studies in larger cohorts are warranted to help confirm these findings and better define the potential advantages and limitations of this technique.

Background/Objectives: Postoperative opioid exposure after lumbar fusion remains a key clinical concern. Understanding which perioperative factors are associated with lower postoperative opioid use may help optimize recovery after minimally invasive (MIS) transforaminal lumbar interbody fusion (TLIF). This study aimed to determine if patients undergoing MIS-TLIF under spinal anesthesia (SA) showed lower postoperative opioid use compared to those undergoing MIS-TLIF under general anesthesia (GA). Methods: We retrospectively studied all adult patients (>18 years) undergoing 1- and contiguous 2-level MIS-TLIFs performed by a single surgeon. Patients undergoing the procedure under GA were compared to those undergoing the procedure under SA. Postoperative oral opioid use, up to 3 months post discharge, was collected. A 1:1 propensity score matching (PSM) protocol was implemented. Each outcome variable was initially assessed using univariate regression. Predictor variables with a p-value < 0.2 were included in the multivariate regression model. This was a retrospective, non-randomized study, and residual confounding cannot be excluded despite PSM. Results: The matched groups (n = 50 in each group) did not differ significantly depending on demographics or levels fused. Before regression, mean number of postoperative opioid prescriptions (p = 0.03), mean total operating room (OR) time in minutes (p < 0.01), and median length of stay (LOS) in days (p = 0.03) were significantly different. Multivariate regression showed that the GA group received 216.5 more total morphine milligram equivalents than the SA group (95% CI = 0.7–432.2, p = 0.049). The days of opioid use were higher in the GA group by 3.8 days (95% CI = 0.5 to 7.1, p = 0.025). On multivariate regression, LOS in hours was greater in the GA group by 14.1 h (p = 0.042). Conclusions: SA is an effective anesthetic modality for spinal surgery with the advantages of reduced postoperative opioid use, reduced OR time, and shorter LOS compared to GA.

OBJECTIVE The implementation of robotics and spinal anesthesia (SA) in spine surgery is rapidly expanding, offering significant benefits for an increasingly complex and aging patient population with degenerative spinal disease. Here, the authors present the largest cohort to date evaluating the combined use of these two techniques in minimally invasive (MIS) transforaminal lumbar interbody fusion (TLIF). METHODS The authors retrospectively analyzed surgical outcomes of a series of patients who underwent robot-assisted (RA)–MIS TLIF under SA and general anesthesia (GA) at their institution from 2018 to 2024. Primary outcomes included operative times and postoperative pain intensity. Secondary outcomes included estimated blood loss, intraoperative complications, postoperative functional status, length of stay (LOS), and discharge status. To address potential confounders, a 1:1 propensity score–matching and regression analysis was implemented. Statistical analyses were conducted using Python. RESULTS A total of 209 patients underwent RA-MIS TLIF, with 31 (14.83%) receiving SA and 178 (85.17%) GA. After propensity score matching, the SA cohort demonstrated significantly shorter median total operating room (OR) time, total procedure time, time from entering the OR to skin incision, and time from closure to leaving the OR (all p < 0.01). Additionally, postoperative pain scores were significantly lower (p < 0.01), and LOS was significantly shorter (p < 0.01) in the SA cohort. Regression analysis, adjusting for potential confounders, further supported these findings. CONCLUSIONS RA-MIS TLIF fusion under SA is a safe and effective approach that significantly reduces operative time, postoperative pain, and hospital LOS in patients undergoing surgery for degenerative lumbar spine disease.

Abstract BACKGROUND CNS ependymal tumors rarely demonstrate mixed subependymal and ependymal pathology. The clinical course of these tumors is difficult to predict, but prior studies have identified TERT mutations and loss of chromosome 6 as poor prognostic factors in these tumors when located in the posterior fossa. METHODS In this retrospective single-institution study, patients with a diagnosis of mixed subependymoma/ependymoma were identified and chart reviewed to describe demographics, pathological findings, treatment courses and clinical outcomes. RESULTS Eleven patients (median age 57, 2 female, 9 male) were identified. Ten tumors were in the posterior fossa and 1 in the cervical spine. At diagnosis, 2 underwent gross total resection, 8 underwent subtotal resection, and 1 was only biopsied. Radiotherapy was administered to 5 patients at initial diagnosis (54Gy in 30 fractions). Systemic therapy (temozolomide and bevacizumab) was administered at recurrence to 2 patients. Loss of chromosome 6 was present in 5 /11 patients and TERT mutations were present in 4/11 patients, with both present in 3/11 patients. Median progression-free survival (mPFS) was 90.1 months (95% CI: 90.1–NA), with 3 progression events observed at 22, 90, and 107 months. Median follow-up duration was 27.9 months. Receiving radiotherapy had a longer mPFS (98 vs 22 months, p=0.15), although non-significant. At the time of data cut-off none of the patients were deceased. CONCLUSIONS Mixed subependymoma/ependymoma is a rare diagnosis with varying clinical outcomes. Our case series demonstrated that the majority of patients did not exhibit the previously identified poor prognostic factors. Although non-significant due to limited case numbers, radiotherapy was suggestive of longer mPFS.

Background/Objectives: Chordoma, a rare slow-growing malignant bone tumor, remains therapeutically challenging due to its invasive nature. We examined institutional outcomes comparing imatinib and brachyury-directed vaccines. Methods: We used data from three sites of our quaternary care academic institution to analyze demographics, time to progression, overall survival, and adverse events in chordoma patients treated with imatinib or enrolled in a brachyury vaccine trial. Results: We included a total of 52 patients (8 in the brachyury vaccine cohort and 44 in the imatinib cohort) in the analysis. As expected, sacrococcygeal location was the most predominant in both cohorts: 62.5% in the brachyury cohort and 45.5% in the imatinib cohort. No demographic differences were present between the cohorts. ECOG was similar in both groups (p = 0.796). The primary outcome, time to progression (TTP), was shorter in the brachyury compared to the imatinib cohort (5.6 vs. 13 months, p = 0.0589), almost reaching statistical significance. Overall survival (OS) was comparable, 211 vs. 212 months for the brachyury and imatinib cohorts, respectively (p = 0.277). Although the brachyury vaccine cohort presented a higher incidence of adverse events than the imatinib cohort (75% vs. 31.8%, p = 0.021), the severity was milder. Conclusions: Imatinib showed longer disease control than the brachyury vaccine, though overall survival was similar. Future studies and deeper molecular insights are essential to develop better therapies and improve patient quality of life.

e13121 Background: Metastatic breast cancer remains a major clinical challenge, characterized by poor prognosis and limited therapeutic options. The incidence of metastatic female breast cancer increased from 5.8 to 7.9 per 100,000 females from 2001 to 2021. The Hippo pathway effector YAP1 plays a critical role in driving tumor growth and metastasis in many cancers including breast but little is known about the gene-specific changes that occur when breast cancers have metastasized. This study aimed to investigate the extent of genomic alterations, including copy number alterations (CNAs) and mutations, in YAP1 and its downstream genes in metastatic breast cancer compared to nonmetastatic breast cancer. Methods: Genomic data for the YAP1 gene and its downstream target genes (CTGF, Cyr61, MCL-1, TOP2A, FOSL2, and ANKRD1) were obtained from cBioPortal. This included mutation data and CNA data, considering both amplifications and deletions as CNA events. The chi-square test was performed using GraphPad Prism 10 to compare the frequencies of mutations and CNAs between metastatic and non-metastatic breast cancer cases. Results: A total of 2390 samples of metastatic breast cancer and 9289 samples of non-metastatic breast cancer were analyzed for mutations. Among them, a significantly higher percentage of mutations in the YAP1 (P ≤ 0.0001), ANKRD1 (P ≤ 0.0001), MCL-1 (P ≤ 0.0001), and TOP2A (P ≤ 0.0001) genes was observed in metastatic breast cancer compared to non-metastatic breast cancer. Evaluating CNAs in 2197 cases in the metastatic breast cancer group compared to 9289 cases in the non-metastatic breast cancer group demonstrated a significantly higher frequency of CNAs in the YAP1 ( P ≤ 0.0001), Cyr61 (P ≤ 0.0001), CTGF ( P ≤ 0.0001), ANKRD1 ( P ≤ 0.0001), TOP2A (P ≤ 0.0001) and FOSL2 (P ≤ 0.0001) genes among metastatic breast cancer. Conclusions: This study revealed significant genomic alterations in the YAP1 gene and its downstream genes in metastatic breast cancer. These findings highlight the importance of the YAP1 pathway in breast cancer metastasis and suggest that targeting this pathway may have therapeutic potential for primary and metastatic breast cancer. Frequency of mutations and copy number alterations (CNAs) in metastatic vs. non-metastatic breast cancer. Gene Metastatic Breast Cancer Mutation Frequency (%) Non-Metastatic Breast Cancer Mutation Frequency (%) P-value Metastatic Breast Cancer CNA Frequency (%) Non-Metastatic Breast Cancer CNA Frequency (%) P-value YAP1 0.75 0.17 <0.0001 5.1 1.18 <0.0001 CTGF 0.13 0.18 0.781 5.42 0.65 <0.0001 Cyr61 0.17 0.16 0.999 3.9 0.65 <0.0001 MCL-1 0.63 0.11 <0.0001 10.74 11.93 0.121 ANKRD1 1.17 0.09 <0.0001 1.96 0.25 <0.0001 TOP2A 0.96 0.18 <0.0001 8.06 3.6 <0.0001 FOSL2 0.17 0.1 0.317 3.64 0.62 <0.0001

Study Design Systematic Review. Objective To assess the current literature regarding the accuracy of different imaging modalities and criteria used to assess lumbar fusion, and their correlation with surgical direct observation as the current Gold Standard. Methods Following PRISMA guidelines, we conducted a comprehensive search of PubMed, Embase, Google Scholar, and Cochrane Library, studies were included if they focused on patients with a prior history of lumbar interbody fusion and at least 1 year of radiographic follow-up. The review assessed the sensitivity, specificity, and accuracy of different imaging techniques, and their correlation with surgical findings. Results Thirteen studies (1989-2019) were reviewed, including 715 patients, common imaging modalities included plain radiographs (53.8%), Computed Tomography (CT) (69.2%), and dynamic radiographs (30.7%). CT appeared as the most utilized modality post-2006. There was substantial variability in diagnostic accuracy, with CT showing high variability in sensitivity and specificity. Descriptive criteria for fusion were widely used, but interobserver agreement was generally low. Conclusion The review highlights a lack of standardized criteria for assessing lumbar fusion. Despite advancements in imaging techniques, the variability in diagnostic parameters suggests a need for consensus and multicentric studies to stablish reliable, universal criteria for evaluating fusion success.

Background: Chordoma is a rare bone cancer with limited treatment options. Clinical trials are crucial for developing effective therapies, but their success depends on including diverse patient populations. The objective of this study was to systematically evaluate the reporting of racial, ethnic, and socioeconomic diversity in United States clinical trials exploring treatment for chordoma. Methods: A literature search was conducted through PubMed/Medline, Cochrane, Epistemonikos, and ClinicalTrials.gov databases for published US chordoma trials up until 19 August 2024. The data collected included trial characteristics and racial and ethnic data, as well as socioeconomic indicators when available. Methodological Index for Non-Randomized Studies (MINORS) and Revised Cochrane Risk-of-Bias Tool for Randomized Trials (RoB2) analyses were adopted to assess the methodological quality. The N-1 Chi-squared (χ2) test was implemented to compare the reported racial and ethnic data with the most recent US Census Bureau data. Results: Five trials involving 111 patients (median age: 63 years; 34% female) were included. Four studies (80%) were single-arm non-randomized studies with one study (25%) having a high methodological quality and three (75%) having a moderate quality based on the MINORS analysis. Most patients (91%, n = 82) were White/Caucasian, representing a proportion which was significantly higher than the reported 75% in the US population (p = 0.0005). Black/African American patients (2%, n = 2) were significantly underrepresented compared to the 14% in the US population (p = 0.0015). Regarding ethnicity, Hispanic/Latino patients (7%, n = 6) were significantly underrepresented compared to the 20% in the US population (p = 0.0021). No measures of socioeconomic status were reported. Conclusions: This systematic review highlighted the need for improved racial and ethnic diversity in chordoma trials and the better reporting of socioeconomic data. The underrepresentation of minority groups may obscure potential disparities in disease incidence, treatment access, and clinical outcomes.

BACKGROUND Rotational vertebral artery occlusion, or bow hunter’s syndrome (BHS), is a rare but clinically important cause of vertebrobasilar insufficiency. Extrinsic compression of the artery is usually caused by osteophytes, fibrous bands, or lateral disc herniation and typically occurs in the setting of anatomical variations, leading to dynamic compromise of the posterior circulation. Neoplastic causes of BHS are rare. OBSERVATIONS The authors present the case of a 72-year-old man with a left vertebral artery–dominant posterior circulation and isolated small right vertebral artery terminating in the posterior inferior cerebellar artery (PICA). He developed progressively worsening dynamic insufficiency of his right PICA circulation due to compression of the right vertebral artery at C2 from an intradural-extradural dumbbell-shaped lesion. This patient was successfully treated via surgical debulking of the lesion and cervical spine fixation and experienced no neurological deficits postoperatively. LESSONS This neoplastic change represents an exceedingly rare presentation for BHS, which warrants further study on its etiology and treatment. https://thejns.org/doi/10.3171/CASE24415

OBJECTIVE Surgical decompression is often indicated for symptomatic cases of cervical radiculopathy. In the cervical spine, minimally invasive posterior cervical foraminotomy (MIS-PCF) and the anterior transcorporeal approach (ATCA) are modern techniques available to surgeons. This systematic review and single-arm meta-analysis aimed to assess surgical and patient-reported outcomes of MIS-PCF and ATCA for cervical radiculopathy. METHODS A systematic review of the literature was conducted using 1) Ovid; 2) Epub Ahead of Print and In-Process, In-Data-Review & Other Non-Indexed Citations; and 3) Scopus databases, which reported outcomes following cervical decompression using MIS-PCF or the ATCA. Specifically, baseline characteristics, operative outcomes, and changes in visual analog scale (VAS) neck pain score were assessed. The quality of the studies was graded using the modified Newcastle-Ottawa Scale for observational studies. RESULTS Forty studies with 1661 patients were identified. The comparative analysis of both techniques revealed no significant differences in complication (7%, 95% CI 5%–10%, p = 0.75) or reoperation rates (5%, 95% CI 3%–7%, p = 0.41). Additionally, there were no significant differences in estimated blood loss (55.39, 95% CI 44.62–66.16 ml, p = 0.55) or operative time (85.15, 95% CI 65.38–104.92 minutes, p = 0.05). The ATCA showed significantly greater improvement (p < 0.01) in VAS neck pain scores following surgery (ATCA point reduction 6.7, 95% CI 6.0–7.5 points vs MIS-PCF 3.0, 95% CI 1.0–5.0 points). CONCLUSIONS The ATCA and MIS-PCF are effective modern techniques for the surgical treatment of radiculopathy. Both approaches showed comparable postoperative outcomes, including complication and reoperation rates. However, the ATCA was shown to provide significantly greater improvement in VAS neck pain scores.